The Anesthesia Consultant is written by Richard Novak, MD, an Adjunct Clinical Professor of Anesthesiology, Perioperative and Pain Medicine at Stanford University.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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CardioPulmonary Resuscitation in the Operating Room
The Stanford Emergency Manual has become an essential reference for anesthesiologists. The manual lists diagnostic and therapeutic steps to follow in 26 different emergency scenarios. When a Code Blue or a dire change in vital signs occurs in an operating room, the Manual directs the resuscitation team to the correct order of action at a time when minds are racing, thoughts have become jumbled, and near-perfect intervention is required.
In addition to Advanced Cardiac Life Support (ACLS) algorithms, the Stanford Manual lists specific instructions on the management of:
Anaphylaxis
Bronchospasm
Delayed Emergence
Difficult Airway/Cricothyrotomy
Embolism – Pulmonary
Fire – Airway
Fire – Non-Airway
Hemorrhage
High Airway Pressure
High Spinal
Hypertension
Hypotension
Hypoxemia
Local Anesthesia Toxicity
Malignant Hyperthermia
Myocardial Ischemia
Oxygen Failure
Pneumothorax
Power Failure
Right Heart Failure
Transfusion Reaction
Trauma
Why implement an Emergency Manual?Supported by published literature, the Stanford group cites these reasons on their webpage:
“Medical simulation studies show that integrating an emergency manual into the operating room results in better management during crises events.
Pilots and nuclear power plant operators use similar cognitive aids for emergencies and rare events.
During a crisis event, the stacks of relevant literature are rarely accessible.
Memory worsens under stress and distractions interrupt our planned actions.
Expertise requires significant repetitive practice, so none of us are experts in every emergency.”
The Emergency Manual was created by the same team which pioneered simulator training for anesthesiologists, headed by Stanford faculty members Drs. David Gaba, Steven Howard, and Sara Goldhaber-Fiebert. The term “cognitive aid” is an academic term referring to resources which help people to remember or apply relevant knowledge appropriately, but since “cognitive aid” is not a familiar term to most anesthesia professionals, the Stanford authors call the book an Emergency Manual, a term which has developed broad acceptance. The Stanford group published the academic article “Emergency Manual Uses During Actual Critical Events and Changes in Safety Culture From the Perspective of Anesthesia Residents: A Pilot Study” in 2016, and “Clinical Uses and Impacts of Emergency Manuals During Perioperative Crises” in 2020. Both articles describe the successful implementation of the Emergency Manual. Both were published in the journal Anesthesia and Analgesia.
This example illustrates the utility of the Stanford Emergency Manual:
An anesthesiologist is working at a freestanding outpatient surgery center, and is scheduled to anesthetize a patient for an arthroscopic rotator cuff repair. Prior to the surgery, the anesthesiologist is performing an ultrasound-guided interscalene nerve block when the patient suddenly loses consciousness and then develops cardiovascular collapse following the injection of the local anesthetic bupivacaine. The attending anesthesiologist remembers that the treatment for Local Anesthesia Toxicity involves injecting Intralipid intravenously, but he/she doesn’t remember the dose. The patient is turning blue and lacks pulses.
The anesthesiologist calls out to the circulating nurse to bring in the Code Blue cart, hands his pocket copy of the Stanford Emergency Manual to a second nurse, and tells her to turn to the page on Local Anesthetic Toxicity and read the treatment instructions out loud. The nurse does so, and begins reading from these following pages from the Manual:
The anesthesiologist calls for Intralipid stat, while the nurse reads each line from the Emergency Manual treatment. The anesthesiologist follows the algorithm, intubates the trachea, and begins ventilating 100% oxygen into the patient’s lungs. CPR is started because there are no palpable pulses. The anesthesiologist then begins administering doses of Intralipid per the Manual. The patient is stabilized and eventually survives without any adverse outcome.
At the Palo Alto multi-specialty surgery center where I am the Medical Director, one Manual is available for the operating rooms and a second Manual hangs on the Code Blue Cart. We teach a Mock Code or a Malignant Hyperthermia drill every six months, and we rehearse the use of the Stanford Emergency Manual during each drill.
If the facilities you work at don’t have copies of the Stanford Emergency Manual, get yourself a Pocket Emergency Manual.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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By Rick Novak
Extasy Books, 331 pages, Format: eBook and paperback
Star Rating: 5 / 5
Author Rick Novak, MD, does an exquisite job of crafting a scenario in which a man is accused of murdering his lover and her husband and brings it all the way into a full jury trial. Call From the Jailhouse introduces readers to top defense attorney Cicely Vella. Cicely is a savage in the courtroom and is able to present to the jury all the reasons why they should acquit. Cicely’s marriage to an anesthesiologist named Sam Vella ended in divorce almost a year and a half ago, although there were certainly times when she missed him. When Sam calls Cicely from the county jail and tells her he is being accused of murder, Cicely knows she must defend him. Although their marriage didn’t work out, Cicely knows Sam didn’t kill anyone.
I loved the way the book was crafted. It starts with the phone call and then goes back in time six months to tell the readers about how Sam meets his married lover, Scarlett. The story is carefully told, with no important detail left out. As a San Francisco Bay Area native, I loved that I knew where so many of the referenced places were, including the Pacific Athletic Club (now The Bay Club), the Stanford Dish, and Kings Mountain Road. I admit that I looked up the Mahogany, where Sam meets Scarlett, and as I guessed, there was no such place listed. It seemed like it could have been modeled after the Rosewood Hotel in Menlo Park.
Call From the Jailhouse moves at the perfect pace. As Sam and Scarlett’s secret relationship starts to bloom, Sam finds himself falling in love with her even though she treats him like she owns him. So, how does Sam find himself accused of murder?
The last half of the book is dedicated to Cicely defending Sam in court. All evidence seems to lead to Sam, even though most of it is circumstantial. They say, write what you know, so Novak’s extensive knowledge in the medical field allows him to cleverly insert medical references, such as a medicine used to paralyze patients to allow doctors to insert a breathing tube. It’s details such as this that give the readers a full understanding of the events that take place in the book.
The court case is my favorite part of the book. This is also where there is a huge twist in the plot that gets uncovered. Cicely is a fantastic attorney who has integrity, grit, and grace all rolled into one small Black woman. Sam is a romantic at heart who finds himself in a black widow’s web. Call From the Jailhouse has fabulous characters, beautiful backdrops, and a plot that will pull you closer with every page.
Reviewed by Kristi Elizabeth
OUR STAR RATING SYSTEM 5 stars: Reviewer considers the book to be something that everyone should read. Reviewer would definitely read it again.
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CALL FROM THE JAILHOUSE excerpt:
Chapter One: The Call
Cicely Vella’s receptionist announced, “Ms. Vella, your ex-husband is on line one. He says he’s in jail. He wants to talk to you.”
There are mileposts in life—moments that alter the future in earthshattering ways. The sudden change can be terrific or tragic. Cicely used to think her defining moment was the end of her marriage, but instead her defining moment occurred when she picked up line one and said, “Sam, what’s going on?”
His voice came through pressured and loud, so robust she had to hold the phone six inches away from her ear. “There’s been some kind of mistake,” he said. “The police arrested me. I’m in trouble.”
Cicely was shocked. Sam had never called her since their divorce, and she’d never heard this tone in his voice. He’d always been cool, calm, and controlled, even in the most stressful times. Cicely couldn’t hide her alarm. “Arrested you for what?”
“Murder.”
Cicely almost dropped the phone. “Murder? You’ve got to be kidding. Where are you right now?”
“The San Mateo County Jail. I need a defense attorney. I need you. Please help me.”
Cicely pictured Sam Vella sitting alone in a jail cell, and her response surprised her. She leapt out of her chair, ready to go to him. “I’ll be there in twenty minutes,” she said. “And don’t answer any questions from anyone until I arrive. Got that?”
“I won’t. And thank you so much for doing this for me.”
“I haven’t done anything yet.” Cicely hung up the phone, feeling the room spinning around her. This wasn’t possible. Sam was a smart guy—an altruistic medical doctor who simply couldn’t kill anyone. He’d been a flawed husband, a man who never quite got used to his overachieving wife’s career eclipsing his, but he wasn’t wired to commit violent crime. Cicely grabbed her purse and car keys and headed for the door. A petite Black woman, Cicely wore a gray wool pantsuit and a Brooks Brothers white cotton shirt. Her androgynous attire was her statement that, in the male-dominated world of litigating attorneys, she had the power to match up with her masculine opponents. Her business—the world of defendants and their alleged misdeeds—was a grim reality of treachery, deceit, ruses, and lies. Cicely didn’t see her vocation as a quest for truth, but rather a competition in search of victory. It was her job to conjure deception. Her joy came from constructing any reasonable alternative to the allegations of the prosecution. Every new case was a puzzle with a yet undiscovered solution. Finding that solution was the most enjoyable pastime Cicely had ever discovered. The money was good, but she knew in her heart she might even have done it for free.
It was that fun.
As Cicely exited through the waiting room, her receptionist said, “I overheard your conversation with Sam. Are you going to defend him?”
“Hell, yes. What kind of defense attorney would I be if my ex-husband spent the rest of his life rotting in prison as a convicted murderer?”
“You’ll be center stage if you defend him.”
“I’ll be center stage whether I’m his lawyer or not. We share a last name. We share a past. I’m going to the jail. I don’t know when I’ll be back.” Cicely’s thoughts were in turmoil. Her divorce was fresh—only one year old. After five workaholic years as man and wife, she and Sam painted themselves into two distant corners—a sad California career-trumps-love divorce. She’d pulled the plug on their marriage and concentrated on climbing to the pinnacle of the legal world. Cicely had only seen Sam twice since the divorce, and each time she felt the same two opposing emotions―a strong attraction to his physical presence, and sadness that the man who had once been her best friend was a stranger to her now.
Cicely knew the drive from her office to the jail very well. She met most of her clients for the first time within those very walls. Minutes later she sat face-to-face with Sam in a windowless white-walled room. He wore an orange jumpsuit with the number 71427 scrolled across his chest. His hair was parted in the middle, lanky and wet, as if he’d just stepped out of a storm, and his gaze never left Cicely. Her heart raced to be sitting so close to him again. He looked as vulnerable as a lost puppy and as breathtaking as any man she had ever set eyes on. Cicely skipped any pleasantries and started with the obvious question, “Who are you accused of killing, Sam?”
He shook his head and dropped his stare toward the table separating them. Then his eyes flicked upward for a second, partially hidden below thick hooded brows, and he said, “It was this woman I was dating. They claim I killed her. And they claim I killed her husband, too.”
“Two murders? Good God.” Cicely exhaled mightily. “Tell me what happened, starting when you first met this-this woman.” Cicely balanced her pen over an 8.5 X 14-inch yellow legal pad and prepared to chronicle Sam’s story.
“Her name was Scarlett,” Sam said. “It all started one rainy January night last winter…”
*
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CALL FROM THE JAILHOUSE: NOW AVAILABLE ON AMAZON LINK:
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Picture this: prior to surgery you place a blood pressure cuff around the middle phalanx of your patient’s right middle finger, instead of a standard cuff on the upper arm, to measure blood pressure. Is this the future? After decades of watching intermittent readings from oscillometric (standard) blood pressure cuffs, will we be monitoring data from a continuous finger-cuff instead?
Perhaps.
A study in the September 2023 issue of Anesthesiology showed that continuous finger-cuff arterial pressure monitoring helped anesthesia professionals a) reduce hypotension during the 15 minutes following induction of general anesthesia, and b) reduce hypotension during the duration of noncardiac surgery, compared to traditional intermittent oscillometric arterial pressure monitoring.
The study was done in a single medical center, the University Medical Center Hamburg–Eppendorf in Hamburg, Germany. A total of 242 patients aged 45 and older who were scheduled for noncardiac surgery were randomized to continuous finger-cuff arterial pressure monitoring or to intermittent traditional oscillometric arterial pressure monitoring. The continuous finger-cuff arterial pressure monitor used was the ClearSight system manufactured by Edwards Lifesciences, USA.
Edwards ClearSight Monitoring System
An appropriately sized finger-cuff (small, medium, or large) was positioned on the middle phalanx of the third or fourth finger of every patient, along with a standard intermittent oscillometric arterial pressure monitor on the opposite arm. Traditional oscillometric arterial pressures were measured at 2.5 minute intervals. The clinical monitoring for each patient was randomized to be either 1) unblinded continuous finger-cuff arterial pressure monitoring, or 2) intermittent standard oscillometric arterial pressure monitoring with the finger-cuff data blinded. The Hamburg medical center’s institutional routine was to maintain MAP (mean arterial pressure) above 65 mmHg, and intraoperative hypotension was treated with intravenous norepinephrine, which was given at the discretion of each attending anesthesiologist.
The Anesthesiology study had two primary endpoints. The first was the amount of hypotension during the 15 minutes following the induction of anesthesia, and the second was the time-weighted average MAP less than 65 mmHg during the entire surgery. Results showed that continuous finger-cuff arterial pressure monitoring helped anesthesia providers a) reduce hypotension within the first 15 minutes after starting induction of anesthesia, and b) reduce hypotension during the entire noncardiac surgery. Patients assigned to continuous finger-cuff monitoring received more than twice as much norepinephrine both within 15 minutes after starting induction of anesthesia and during the entire surgery, when compared with patients assigned to intermittent oscillometric monitoring. This presumably explains why there was significantly less hypotension in the continuous finger-cuff monitoring group.
The Edwards Lifesciences website describes the ClearSight continuous finger-cuff monitoring system. In addition to continuous blood pressure monitoring, the ClearSight system records advanced hemodynamic parameters from the noninvasive finger cuff, including graphic trend displays on the Edwards Lifesciences HemoSphere monitor of:
• Cardiac output (CO)
• Stroke volume (SV)
• Stroke volume variation (SVV), and
• Systemic vascular resistance (SVR).
These parameters provide additional information which, if validated, can expand the information an anesthesia provider can monitor routinely. The parameters of continuous blood pressure (ART), continuous Mean Arterial Pressure (MAP), Cardiac output (CO) and Stroke volume (SV) are shown on the HemoSphere monitor below.
The technology behind the ClearSight continuous finger-cuff monitor involves a principle called the volume clamp method. Per the Edwards Lifesciences website, this “involves clamping the artery in the finger to a constant volume, by dynamically providing equal pressure on either side of the arterial wall. The volume is measured by a photo-plethysmograph built into the cuff. The counter pressure is applied by an inflatable bladder inside the cuff and is adjusted 1000 times per second to keep the arterial volume constant. Continuous recording of the cuff pressure results in real-time finger pressure waveform.”
Volume clamp cross section
Interior of the Edwards finger-cuff
Dr. Daniel Sessler, one of the world’s most respected and prolific anesthesia researchers, is a co-author of the recent Anesthesiology study. To me this validates the notion that continuous finger-cuff technology may eventually gain widespread adoption in operating room monitoring. (Note also that Dr. Sessler is a consultant for Edwards Lifesciences, and has received research funding from the company, as have some of the other authors of the Anesthesiology study.)
Would data show that more frequent utilization of oscillometric (standard) blood pressure readings, recordedwith our existing equipment every one minute instead of every 2.5 minutes, give as much information as a continuous finger-cuff?
If a patient’s hand or fingers are jiggled or moved during monitoring, would the continuous finger-cuff give significant artifacts?
Would clinicians use both traditional blood pressure cuff monitoring and continuous finger-cuff monitoring on the same patient, and make physiologic conclusions from both sources of input?
Will other models of finger-cuff monitoring, different from the Edwards Lifesciences ClearSight model, vary in accuracy? Will clinicians trust new finger-cuff monitoring devices and their data?
What will be the price of this technology?
The benefit/risk ratio of continuous finger-cuff monitoring appears to be high. The technology is noninvasive and unlikely to harm our patients in any way, as long as the data is accurate. The dollar cost of this new technology will influence its rate of adoption. Existing intermittent oscillometric (traditional) blood pressure monitoring devices are already present in every operating room as standard equipment on today’s budgets. If continuous finger-cuff blood pressure monitoring is both accurate and inexpensive, the new technology may be universally adopted. But because a majority of anesthetics are administered to reasonably healthy ASA 1 or ASA 2 patients, many of them in outpatient surgery centers, one could argue that measuring intermittent blood pressures every 2.5 to 3 minutes with oscillometric (traditional) blood pressure monitoring devices is an adequate monitoring interval for these patients. If the added cost of continuous finger-cuff monitoring is excessive, this technology may be limited to hospitals, where sicker patients are anesthetized for bigger and more invasive surgical procedures, and which present increased risk for patients with hypotension.
The Food and Drug Administration recently approved an additional monitoring system based on finger-cuff technology from Edwards Lifesciences, the Acumen Hypotension Prediction Index (HPI) software system. This system uses machine learning to alert clinicians of the likelihood a patient is trending toward hypotension, or low blood pressure.
Keep your eyes open for further studies on the ClearSight system, the Acumen system, and other continuous finger-cuff monitoring equipment. This technology may become part of our operating room life in the near future.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Litigator Cicely Vella’s ex-husband is arrested for a double murder, and asks her to be his defense lawyer. Cicely rarely loses a case, but her extraordinary record is in jeopardy when she chooses to defend Sam Vella, the only suspect in what appear to be two indefensible crimes.
Cicely is living the dream life of a young professional. She’s bright, beautiful, Black, and successful, but she harbors one weakness—lingering feelings for Sam, the husband who got away.
Samuel Vella is a physician with high intellect, striking good looks, and a proclivity for making poor decisions. In the aftermath of his split from Cicely, Sam initiates an affair with Scarlett Lang, a free-spirited married woman, and their liaison lands Sam behind bars.
After receiving Sam’s call from the jailhouse, Cicely feels the triple lures of her emotional attachment to her ex-husband, the opportunity to redeem the Vella name in the courtroom, and her zest for fame in this sensational high-profile trial. Nothing in the world but this court date could make Cicely and Sam sit elbow to elbow, day after day.
The odds of a divorced couple remarrying the same person are 6 in 100, a statistic Cicely is both aware of and wary of, as she’s drawn back into Sam’s life.
*
*
CALL FROM THE JAILHOUSE excerpt:
Chapter One: The Call
Cicely Vella’s receptionist announced, “Ms. Vella, your ex-husband is on line one. He says he’s in jail. He wants to talk to you.”
There are mileposts in life—moments that alter the future in earthshattering ways. The sudden change can be terrific or tragic. Cicely used to think her defining moment was the end of her marriage, but instead her defining moment occurred when she picked up line one and said, “Sam, what’s going on?”
His voice came through pressured and loud, so robust she had to hold the phone six inches away from her ear. “There’s been some kind of mistake,” he said. “The police arrested me. I’m in trouble.”
Cicely was shocked. Sam had never called her since their divorce, and she’d never heard this tone in his voice. He’d always been cool, calm, and controlled, even in the most stressful times. Cicely couldn’t hide her alarm. “Arrested you for what?”
“Murder.”
Cicely almost dropped the phone. “Murder? You’ve got to be kidding. Where are you right now?”
“The San Mateo County Jail. I need a defense attorney. I need you. Please help me.”
Cicely pictured Sam Vella sitting alone in a jail cell, and her response surprised her. She leapt out of her chair, ready to go to him. “I’ll be there in twenty minutes,” she said. “And don’t answer any questions from anyone until I arrive. Got that?”
“I won’t. And thank you so much for doing this for me.”
“I haven’t done anything yet.” Cicely hung up the phone, feeling the room spinning around her. This wasn’t possible. Sam was a smart guy—an altruistic medical doctor who simply couldn’t kill anyone. He’d been a flawed husband, a man who never quite got used to his overachieving wife’s career eclipsing his, but he wasn’t wired to commit violent crime. Cicely grabbed her purse and car keys and headed for the door. A petite Black woman, Cicely wore a gray wool pantsuit and a Brooks Brothers white cotton shirt. Her androgynous attire was her statement that, in the male-dominated world of litigating attorneys, she had the power to match up with her masculine opponents. Her business—the world of defendants and their alleged misdeeds—was a grim reality of treachery, deceit, ruses, and lies. Cicely didn’t see her vocation as a quest for truth, but rather a competition in search of victory. It was her job to conjure deception. Her joy came from constructing any reasonable alternative to the allegations of the prosecution. Every new case was a puzzle with a yet undiscovered solution. Finding that solution was the most enjoyable pastime Cicely had ever discovered. The money was good, but she knew in her heart she might even have done it for free.
It was that fun.
As Cicely exited through the waiting room, her receptionist said, “I overheard your conversation with Sam. Are you going to defend him?”
“Hell, yes. What kind of defense attorney would I be if my ex-husband spent the rest of his life rotting in prison as a convicted murderer?”
“You’ll be center stage if you defend him.”
“I’ll be center stage whether I’m his lawyer or not. We share a last name. We share a past. I’m going to the jail. I don’t know when I’ll be back.” Cicely’s thoughts were in turmoil.
Her divorce was fresh—only one year old. After five workaholic years as man and wife, she and Sam painted themselves into two distant corners—a sad California career-trumps-love divorce. She’d pulled the plug on their marriage and concentrated on climbing to the pinnacle of the legal world. Cicely had only seen Sam twice since the divorce, and each time she felt the same two opposing emotions―a strong attraction to his physical presence, and sadness that the man who had once been her best friend was a stranger to her now.
Cicely knew the drive from her office to the jail very well. She met most of her clients for the first time within those very walls. Minutes later she sat face-to-face with Sam in a windowless white-walled room. He wore an orange jumpsuit with the number 71427 scrolled across his chest. His hair was parted in the middle, lanky and wet, as if he’d just stepped out of a storm, and his gaze never left Cicely. Her heart raced to be sitting so close to him again. He looked as vulnerable as a lost puppy and as breathtaking as any man she had ever set eyes on. Cicely skipped any pleasantries and started with the obvious question, “Who are you accused of killing, Sam?”
He shook his head and dropped his stare toward the table separating them. Then his eyes flicked upward for a second, partially hidden below thick hooded brows, and he said, “It was this woman I was dating. They claim I killed her. And they claim I killed her husband, too.”
“Two murders? Good God.” Cicely exhaled mightily. “Tell me what happened, starting when you first met this-this woman.” Cicely balanced her pen over an 8.5 X 14-inch yellow legal pad and prepared to chronicle Sam’s story.
“Her name was Scarlett,” Sam said. “It all started one rainy January night last winter…”
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Street use of the anesthetic ketamine is on the rise. Kylie, a 28-year-old professional female, recently told me about her experience snorting recreational ketamine: “I was feeling anxious and I was feeling sad. My friend suggested I try snorting some ketamine crystals she had, and when I did . . . I had the best feeling of my life. The drug made me happier. It made the next hour a fun experience without any sadness, and when the high wore off an hour later my sadness was still gone. It was as if I’d been treated with some antidepressant drug, and the improvement in my mood was more lasting than the initial buzz. Now I see my future using ketamine as a periodic antidepressant. When you read about it on the internet, doctors are prescribing ketamine as a treatment for depression, but the whole medical clinic intravenous treatment is really expensive. It’s a lot easier to do it myself with ketamine I buy on the streets.”
Hmmm. We’re all aware of the dangers of recreational drug use with cocaine or methamphetamine or narcotics. We’re all aware of the dangers of recreational drugs laced with fentanyl, a powerful drug that can stop a person’s breathing and kill them in minutes. In this context, what kind of a threat is street ketamine?
Anesthesiologists administer ketamine intravenously to produce general anesthesia without utilizing any anesthesia gas. We call ketamine a dissociative drug, because it can distort sensory perception and impart a feeling of detachment from oneself and the environment. The drug can produce bizarre and unpleasant nightmares, so anesthesiologists are trained to pair ketamine with an intravenous benzodiazepine such as Versed to temper ketamine’s potentially frightening dream world. Anesthesiologists are also trained to pair ketamine with an anticholinergic (mouth-drying) medication such as atropine or glycopyrrolate (Robinul), because ketamine can produce excessive salivating, which can lead to a patient choking on a rising tide of saliva.
For anesthesia usage, ketamine is a clear liquid with a concentration of 100 mg/ml or 50 mg/ml.
Because ketamine is an effective general anesthetic in one syringe, it’s included on the World Health Organization’s list of essential drugs. For medical sedation, ketamine is typically diluted and administered intravenously in small boluses of 20 to 30 mg, and titrated to obtain the desired depth of anesthesia. To induce general anesthesia, the intravenous dose is 1 – 4.5 mg/kg, or a mean dose of 2 mg/kg = 100 mg for a 50 kg adult. If it’s not possible to insert an IV line (e.g. if a patient is uncooperative, developmentally delayed, or is a child), a combination of 2 mg/kg of ketamine, 0.2 mg/kg of midazolam, and .02 mg/kg of atropine can be administered as an intramuscular injection into the deltoid muscle of the shoulder or the quadriceps muscle of the anterior thigh. To induce general anesthesia with intramuscular ketamine alone, dosing levels are higher than for intravenous use, for example the intramuscular dose is 6.5 – 13 mg/kg, or a mean dose of 10 mg/kg = 500 mg ketamine for a 50 kilogram adult.
How does medical ketamine affect a patient’s ABCs of airway, breathing, and circulation? Patients typically maintain an adequate airway and breathing during ketamine sedation and anesthesia, which is advantageous in short surgical procedures because this often eliminates the need for a breathing tube. Ketamine causes stimulation of the cardiovascular system, with the potential side effect of increasing blood pressure.
There is no reversal agent for ketamine. If an administered ketamine dose is excessive, a patient’s airway and breathing may become compromised, resulting in inadequate oxygen delivery to the lungs, heart, and brain. Patients who are obese, or who have obstructive sleep apnea, may lose their safe airway and breathing status during ketamine sedation. Ketamine can elevate blood pressure, so vigilant monitoring of the blood pressure is required, and acute treatment for hypertension may be necessary. Because of these risks, ketamine administration is typically limited to anesthesia professionals or physicians who are experts in the emergency management of airways and acute vital sign changes.
KETAMINE AS AN INTRAVENOUS ANTIDEPRESSANT DRUG
Multiple meta-analyses have concluded that IV ketamine is an effective rapid-acting antidepressant for major depressive disorders. Ketamine was first reported to have antidepressant properties in the year 2000, when published data showed that an intravenous administration of a sub-anesthetic ketamine dose resulted in a reduction of symptoms in major depressive disorder (MDD). MDD is a common disorder with significant consequences. A 2012 epidemiological study of mental health in Canada showed the lifetime prevalence of major depressive disorder was 3.9%. The prevalence was higher in women and in younger age groups. Ketamine is a treatment option for patients suffering from treatment-resistant depression (TRD). IV ketamine can exert rapid antidepressant effects as early as several hours after administration. In contrast, traditional oral antidepressant pills usually require several weeks of therapy for a clinical response. Ketamine has a unique mechanism of action on the central nervous system, at the NMDA (N-methyl-D-aspartate) and AMPA (𝛼-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors, rather than at the serotonin and/or noradrenaline neurotransmitters that are the sites of action for traditional antidepressant pills such as Prozac, Paxil, or Zoloft.
In 2019 the FDA approved a nasal spray called Spravato (active ingredient esketamine) for major depression that failed treatment with two or more oral antidepressants.
SPRAVATO® is a non-competitive N-methyl D-aspartate (NMDA) receptor antagonist indicated, in conjunction with oral antidepressant, for the treatment of: treatment-resistant depression in adults, depressive symptoms in adults with major depressive disorder (MDD) with acute suicidal ideation or behavior.
SPRAVATO® is intended for use only in a certified healthcare setting.
SPRAVATO® is intended for patient administration under the direct observation of a healthcare provider, and patients are required to be monitored by a healthcare provider for at least 2 hours. SPRAVATO® must never be dispensed directly to a patient for home use.
The advantage of intranasal ketamine is that it does not require an IV, and it requires monitoring by a healthcare provider but does not require an anesthesiologist to supervise its administration.
How popular is recreational ketamine? The number of ketamine seizures by federal, state and local law enforcement in the United States increased from 55 in 2017 to 247 in 2022. The total weight of ketamine confiscated increased by more than 1,000 percent over the five years. The majority of the confiscated ketamine was in powder form. According to the DEA (Drug Enforcement Agency), powdered ketamine is typically packaged in “small glass vials, small plastic bags, and capsules as well as paper, glassine, or aluminum foil folds. . . . powdered ketamine is cut into lines known as bumps and snorted, or it is smoked, typically in marijuana or tobacco cigarettes. . . . Ketamine is found by itself or often in combination with MDMA, amphetamine, methamphetamine, or cocaine. . . . Ketamine produces hallucinations. It distorts perceptions of sight and sound and makes the user feel disconnected and not in control. A ‘Special K’ trip is touted as better than that of LSD or PCP because its hallucinatory effects are relatively short in duration, lasting approximately 30 to 60 minutes as opposed to several hours. . . . An overdose can cause unconsciousness and dangerously slowed breathing.” (bold lettering mine.)
The website The Cutstates that “most of the recreational users . . . take K in very small doses, seeking a pleasant buzz that wears off within 30 minutes or can be re-upped as needed. It’s often taken to compliment other drugs — a garnish instead of the main course. For a generation that has less free time for sprawling multi-day psychedelic trips, ketamine has an appealing choose-your-own-adventure quality. . . . Claire says it actually feels like a healthier and more mature lifestyle. ‘People are like: I used to go out and have 16 drinks and do a bunch of cocaine and feel like shit the next day. And then it was this total shift [to ketamine]: Oh, yeah, I can do this. And it still feels like stepping out of my life, but I also feel fine tomorrow.’ At this point, she says: ‘I wouldn’t say that it’s different than like, a bunch of people getting off work and going out for drinks.’”
KETAMINE AS A RECREATIONAL ANTIDEPRESSANT?
Can a layperson use ketamine recreationally to treat themself for depression? The specter of self-treatment reminds one of the saying that a physician who treats himself has a fool for a doctor and a fool for a patient. A corollary of this is: a person who treats his or her mood disorder with recreational ketamine has a fool for a caretaker and a fool for a patient.
Kylie will attempt to titrate ketamine recreationally to treat her depression. But a precise, tailored medical dose is required for patients to experience optimal benefit from ketamine with safety. Individuals who self-administer ketamine expose themselves to serious health risks. Ketamine may make their symptoms worse, or they may even die from the habit. Kylie has no plans to have a healthcare provider present when she self-administers ketamine. Kylie has no idea of the milligram dose she is snorting. Her ketamine is not FDA-approved, and may in fact contain fentanyl at a dose that could cease her breathing and kill her.
If Kylie is depressed and seeks relief, an appropriate action would be to consult a psychiatrist. The alternative of intermittent recreational intranasal ketamine as a self-administered treatment for her depression is a dangerous detour.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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This column will help you find the top 10 anesthesia journals. Prior to the internet, hard copies of medical journals were bound into volumes and stored at hospital or medical school libraries. To find a specific article required a dive into the archives of the library, with the eventual reward of finding the specific article and then photocopying it to use for your pending lecture, paper, or patient care. In the internet age, all journals are catalogued in the virtual library of the search engine PubMed. Once you find your desired article, the abstract or sometimes the full text article is available for you to read and/or copy into your personal computer.
With this virtual library model, it makes little sense for individual clinicians to subscribe to monthly journals. Your search for journal references is done via Google or PubMed. Which journals are accessed most often? Traditional academic rankings of journals rely on the “impact factor” of each journal.
Impact factor is defined as the “scientometric index which reflects the yearly mean number of citations of the articles published in the last two years in that journal.” One such impact factor ranking list is located here. The impact factor/rate of citations is different from the number of clicks an article receives on internet searches. How many people actually read an article? There is currently no ranking system to quantitate the important metric of internet clicks, which would document the degree of interest readers have with a specific article or journal.
Clinical anesthesia providers such as myself want to read information which impacts patient care, rather than to read basic science studies such as this one: Pholcodine exposure increases the risk of perioperative anaphylaxis to neuromuscular blocking agents: the ALPHO case-control study. Which journals/publications contain the most valuable clinical information? There are multiple fine journals in our specialty, but in my opinion the top 10 periodical anesthesia publications for clinical information follow below. Note that 2 of the top 4 publications did not even exist when I began my anesthesia training in 1984.
THE 2023 ANESTHESIACONSULTANT.COM LIST OF THE TOP 10 ANESTHESIA PUBLICATIONS:
TEN: Journal of Clinical Anesthesia. Per their website, this journal “addresses all aspects of anesthesia practice, including anesthetic administration, pharmacokinetics, preoperative and postoperative considerations, coexisting disease and other complicating factors, cost issues, and similar concerns anesthesiologists contend with daily. . . . JCA is affiliated with three societies that make it their official journal: the American Association of Clinical Directors (AACD); the Society for Airway Management (SAM); and the Orthopedic Anesthesia Pain Rehabilitation Society (OAPRS).” This publication launched in 1988. Comment: The Journal of Clinical Anesthesia is best known for presenting clinical data regarding relevant questions in the practice of anesthesiology.
NINE: European Journal of Anaesthesiology. Per their website, “The European Journal of Anaesthesiology is the official journal of the European Society of Anaesthesiology and Intensive Care (ESAIC), and all members receive the journal as a benefit of membership.” This publication launched in 1983. Comment: As the flagship publication for the European Society, this journal is a reliable source of recent relevant anesthesia studies.
EIGHT: Regional Anesthesia & Pain Medicine.Regional Anesthesia & Pain Medicine. Per their website, this journal is “the official publication of the American Society of Regional Anesthesia and Pain Medicine(ASRA), a monthly scientific journal dedicated to mitigating the global burden of pain. Coverage includes all aspects of acute, perioperative, transitional, and chronic pain medicine. . . . this respected journal also serves as the official publication of the European Society of Regional Anaesthesia and Pain Therapy (ESRA), the Asian and Oceanic Society of Regional Anesthesia (AOSRA), the Latin American Society of Regional Anesthesia (LASRA), and the African Society for Regional Anesthesia (AFSRA).” This journal launched in 1976. Comment: The diagnosis and treatment of pain is the greatest frontier in the specialty of anesthesiology in the 21st century. Look to Regional Anesthesia & Pain Medicine as the leading journal in this vital subspecialty of anesthesiology.
SEVEN: Journal of Cardiothoracic and Vascular Anesthesia. Per their website, this journal “is primarily aimed at anesthesiologists who deal with patients undergoing cardiac, thoracic or vascular surgical procedures. JCVA features a multidisciplinary approach, with contributions from cardiac, vascular and thoracic surgeons, cardiologists, and other related specialists.” This journal launched in 1987. Comment: The practices of cardiac, thoracic, and vascular anesthesia are the most demanding in our profession, and the Journal of Cardiothoracic and Vascular Anesthesia is the leader in reporting advances in these challenging subspecialties.
SIX: British Journal of Anaesthesia. Per their website, this journal “publishes high-impact original work in all branches of anaesthesia, critical care medicine, pain medicine and perioperative medicine. . . . The journal is proudly affiliated with The Royal College of Anaesthetists, The College of Anaesthesiologists of Ireland, and The Hong Kong College of Anaesthesiologists.” This publication launched in 1923. Comment: This British journal is the second longest running publication of the ten in this list, and is a very well-known and well-respected journal in our profession.
FIVE: Anaesthesia. Per their website, this journal “is the official journal of the Association of Anaesthetists and is international in scope and comprehensive in coverage. It publishes original, peer-reviewed articles on all aspects of general and regional anaesthesia, intensive care and pain therapy.” This publication launched in 1930. Comment: This British journal is the third longest running publication of the ten in this list, and is a well-known and well-respected journal in our profession.
FOUR: The ASA Monitor. Per their website, this is “the official news publication of the American Society of Anesthesiologists. The ASA Monitor delivers the latest specialty and industry news, and practice-changing clinical information to the perioperative health care community.” This publication launched in 2004. Comment: The ASA Monitor byline is“The Leading Source for Perioperative Health Care News.” The ASA Monitor is essentially a monthly newspaper which reports on pertinent topics regarding anesthesiology in the United States. It’s delivered to all members of the American Society of Anesthesiologists.
THREE: The Anesthesia Patient Safety Foundation (APSF) Newsletter. Per their website, this publication’s mission is “to improve the safety of patients during anesthesia care by: Identifying safety initiatives and creating recommendations to implement directly and with partner organizations, being a leading voice for anesthesia patient safety worldwide, and supporting and advancing anesthesia patient safety culture, knowledge, and learning. The APSF Vision Statement is ‘That no one shall be harmed by anesthesia care.’” This publication launched in 1986. Comment: The Anesthesia Patient Safety Foundation Newsletter is the Quality Improvement/Quality Assurance publication for our profession. The editors ferret out current problems in anesthesiology and provide solutions in an attempt to lessen or eliminate complications in the future. The APSF Newsletter should be required reading for all anesthesia professionals in order to best protect our patients.
TWO: ANESTHESIA & ANALGESIA.Per their website, “ANESTHESIA & ANALGESIA is the ‘The Global Standard in Anesthesiology,’ and provides the practice-oriented, clinical research you need to keep current and provide optimal care to your patients. Each monthly issue brings you peer reviewed articles on the latest advances in drugs, preoperative preparation, patient monitoring, pain management, pathophysiology, and many other timely topics. . . . ANESTHESIA & ANALGESIA is the official journal of the International Anesthesia Research Society and all members receive the journal as a benefit of membership.” This publication launched in 1922. Comment: A & A (as this journal is referred to in our profession) is an outstanding publication, second only to Anesthesiology.
ONE: ANESTHESIOLOGY. Per their website, “ANESTHESIOLOGY leads the world in publishing and disseminating the highest quality work to inform daily clinical practice and transform the practice of medicine in the specialty. . . . Founded in 1940, ANESTHESIOLOGY is the official journal of the American Society of Anesthesiologists but operates with complete editorial autonomy, with an independent and internationally recognized Editorial Board.” Comment: Anesthesiology is the blueprint for what a 21st century journal should be, mixing breakthrough science and clinical studies with the all-important American Society of Anesthesiologist standards, guidelines, and practice parameters which define our profession.
My advice? Be intellectually curious about all things related to anesthesiology. Use PubMed and Google to look up questions you want answered. You’ll be directed to many of the publications above, and you’ll be a smarter clinician as a result.
In addition: There are dozens of anesthesia textbooks. I’ve ranked the Top 11 Anesthesia Textbooks in a previous column.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Despite this, during surgery your anesthesiologist injected fentanyl into your IV as part of your anesthetic. Is that safe?
Yes.
As a street drug, fentanyl overdose is a critical problem in the United States, but anesthesiologists administer fentanyl to most patients, and do so safely. I review charts from all regions of the U.S., and virtually every anesthetic includes the safe use of fentanyl. Fentanyl was introduced in the 1960s when it was first patented under the brand name Sublimaze, and fentanyl quickly became the most commonly administered narcotic by anesthesia providers. In operating room anesthesia, the narcotic fentanyl is a clear liquid usually marketed in vials of two milliliters or five milliliters.
Why do anesthesiologists utilize fentanyl? Most surgeries cause pain, and our pharmaceutical options for relieving pain include local anesthetics, anesthesia gases, or narcotics. When possible, we advocate for the injection of local anesthetics by the surgeon or the anesthesiologist to block postoperative pain. Local anesthetics include lidocaine, bupivacaine (also known as Marcaine), or ropivacaine. In addition, most general anesthetics include a potent inhaled anesthesia gas such as sevoflurane. Sevoflurane vapor maintains unconsciousness, blocks memory, and renders a patient pain-free, but when the surgery concludes, the anesthesia gases are turned off so that the patient will awaken. As the anesthesia gas is exhaled, a patient becomes progressively more alert, and will eventually be awake enough to feel surgical pain. The intravenous injection of a narcotic medication such as fentanyl is a common antidote to postoperative pain.
The most serious side effect of intravenous fentanyl in anesthesia usage is the same side effect that makes street fentanyl dangerous, and that’s the side effect of respiratory depression. In layman’s terms, an excessive dose of fentanyl quickly causes a patient to stop breathing. The medical term for cessation of breathing is apnea. In an anesthesiologist’s hands, apnea is easily handled because we are skilled at ventilating oxygen into a patient’s lungs safely via a mask or an airway tube.
Street overdoses of fentanyl are best treated with naloxone (brand name Narcan). Nasal Narcan is now approved for over the counter (OTC) sale in the United States. In a medical setting, intravenous Narcan is injected to reverse a narcotic overdose. Injection of one ampule of Narcan (0.4 mg) will completely reverse narcotic apnea and unconsciousness in an overdosed patient in less than a minute.
The protocol for treating an emergency room patient who is unconscious on admission for unknown reasons includes an empirical intravenous injection of Narcan. If the patient’s coma was caused by any narcotic overdose, the patient will awaken within seconds.
Fentanyl is one hundred times more potent than morphine. Medical fentanyl doses are prescribed in micrograms, while morphine is prescribed in milligrams. One microgram is only 1/1000 of a milligram. A narcotic as potent as fentanyl is typically only utilized by MDs expert at handling apneic patients, and the IV antidote Narcan is always immediately available. Most medical doctors other than anesthesiologists never prescribe intravenous fentanyl. Your general practitioner or primary care doctor will never prescribe fentanyl. A cardiologist may prescribe IV fentanyl sedation for a procedure such as a cardiac catheterization, or a or surgeon may prescribe fentanyl for a superficial excision surgery, but anesthesiologists are typically the only physicians who pick up a fentanyl ampule, insert a needle and syringe into the ampule, and then inject the drug into a patient’s IV. In the intensive care unit (ICU), fentanyl can be used to sedate patients who already have a breathing tube (endotracheal tube) in their windpipe, and who are on a mechanical ventilator. An ICU physician will write an order for the dosing of intravenous fentanyl, and the ICU nurse will be in constant attendance to monitor the patient’s vital signs and level of sedation.
Addiction:
Are you at risk for becoming an addict because your anesthesiologist gives you doses of intravenous fentanyl? No. Most patients have no idea they received IV fentanyl as part of their anesthetic care. The effects of fentanyl wear off within several hours after the end of the surgery, and there is no data that a patient will have a craving for additional fentanyl. After surgery, hospital inpatients who have postoperative pain are typically treated with longer acting narcotics such as morphine or Dilaudid. After surgery, outpatients who have postoperative pain are typically treated with narcotic pain pills such as Oxycontin or Norco. There is no pill form of fentanyl that a patient goes home with, or that a patient can overdose with.
Note that in medical settings, fentanyl can be given by means other than IV injection:
Fentanyl may be given as an ingredient in an epidural or a spinal anesthetic injection. When an anesthesiologist injects the appropriate dose into an epidural or spinal, the patient is monitored in a medical setting for respiratory depression afterwards. The risk of apnea is eliminated by constant monitoring for the duration of the narcotic effect.
Can medical fentanyl be stolen, find its way to the streets, and be a cause of overdose deaths of non-medical people? No. The DEA forces all hospitals, surgery centers, and medical offices to keep a strict tally of all narcotics and controlled substances. At the end of every day, a precise count of all ampules of fentanyl is done, and unless one of the doctors or nurses falsifies their count, it is unlikely any fentanyl escapes a medical facility and winds up in the hands of dealers, addicts, or individuals in the outside world.
Conclusion:
It’s true that medically administered intravenous fentanyl can cause a person to stop breathing, but if an anesthesiologist is present watching every breath, you’re safe. When an airway specialist is present and fentanyl is administered in a hospital operating room, an emergency room, an ambulatory surgery center, or a physician’s office operating room, this represents safe care in the United States today. Don’t worry if you hear your anesthesia provider is going to give you fentanyl. It’s OK. Medical administration of fentanyl has been going since the 1960s. Deaths from fentanyl overdose in a medical setting would be almost unheard of.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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The safe management of a difficult airway is the most important single skill for an anesthesiologist. Every critically ill patient is managed by the priority of A – B – C, or Airway – Breathing – Circulation. Just as the initial most important factors in real estate are location, location, location, the three initial important factors in a critically ill patient are airway, airway, airway. I’ve written previously on the American Society of Anesthesiologists 2022 modifications to their Difficult Airway Algorithm, on the importance of expert airway management, and on advice for avoiding lost airway lawsuits, but I haven’t discussed the economic consequences of each difficult airway patient.
A 2021 publication, “Factors and Economic Outcomes Associated with Documented Difficult Intubation in the United States,” by Moucharite et al, studied the economic cost of a difficult intubation in hospitalized patients. Using data from the Premier Healthcare Database, the study looked at adult patients with inpatient surgical admissions during 2016, 2017, and 2018. Patients in the difficult intubation group had average inpatient costs $14,468 higher than patients without difficult intubations. Patients in the difficult intubation group had average ICU (intensive care unit) costs $4,029 higher than patients without difficult intubations. For difficult intubation patients the mean hospital length of stay was 3.8 days longer and ICU length of stay was 2.0 days longer. All data were significant to a p value of < 0.0001.
The Moucharite study was a large retrospective review of 2,233,751 cases from hospitals in all parts of the United States. With 609 cases in the difficult intubation group and 2,233,142 cases in the non-difficult intubation group, the incidence of difficult intubation was only 0.027%. Difficult intubation patients were more likely be male, black, less than 65 years old, and have urgent or emergent admissions, obesity, cancer, congestive heart failure, COPD, renal disease, and had been treated in a teaching hospital or a hospital of 500 beds or more.
Moucharite wrote, “Difficult intubation has been associated with a variety of complications including oxygen desaturation, hypertension, dental damage, admission to the intensive care unit, and complications at extubation, as well as arrhythmias, bronchospasm, airway trauma, CICV (can’t intubate, can’t ventilate), and sequela of hypoxia (cardiac arrest, brain damage, and death). This was consistent with a 2011 study of difficult airways from the British Journal of Anesthesia which stated, “Obesity markedly increases risk of airway complications. Pulmonary aspiration remains the leading cause of airway-related anesthetic deaths. . . . Unrecognized esophageal intubation is not of only historical interest and is entirely avoidable. . . . prediction scores are rather poor, so many failures are unanticipated . . . the first-pass success rate of intubation in the operating room ranges from only 63% to 85% . . . and up to 93% of difficult intubations are unanticipated.”
The Moucharite study has limitations. It’s a retrospective study of economic Big Data, and there is no direct evidence for a cause-and-effect relationship between a difficult intubation and a more costly hospitalization. The study does not include data from electronic medical records, so we have no knowledge on all the comorbidities and complications of the difficult intubation patients. The study included only hospitalized patients, even though seventy percent of surgical procedures in the United States take place in ambulatory surgery centers and offices outside of hospitals. The reported incidence of difficult intubation is estimated to be 1.5–8.5% of the general population, but in the Moucharite study only 0.027% of patients were found to have difficult intubation. This discrepancy implies some patients in the Moucharite study were difficult intubations but may have been assigned to the non-difficult intubation cohort.
I expect Medtronic could cite the Moucharite study as evidence that a videolaryngoscope (such as a McGrath) is a crucial piece of equipment for avoiding expensive difficult intubation outcomes. Moucharite wrote that there is, “a need for clinicians who perform tracheal intubations to carefully consider options . . . several studies demonstrated the benefits of videolaryngoscopy [emphasis added] including a shorter time required for tracheal intubation, a higher rate of successful intubations.”
For the first look when intubating a patient, most anesthesia providers still use a traditional direct laryngoscope:
MAC 3 DIRECT LARYNGOSCOPE
If the direct laryngoscope does not enable a successful intubation, a reasonable second step is to switch to a videolaryngoscope such as the GlideScope, manufactured by Verathon:
GLIDESCOPE
or the C-MAC, manufactured by Karl Storz:
C-MAC
or the McGrath, manufactured by Medtronic:
McGRATH VIDEOLARYNGOSCOPE
In my experience the larger 6.4-inch screen on a GlideScope or the 5.9-inch screen on a C-MAC makes them superior videolaryngoscopes to the McGrath with its diminutive 2.5-inch screen.
Why use a direct laryngoscope in the initial intubation attempt rather than use a videolaryngoscope? A direct laryngoscope costs less than a videolaryngoscope. Most direct laryngoscopes blades are washed and reused. Videolaryngoscopes require a new disposable sleeve or blade for every case. In facilities with budget concerns, replacing all traditional laryngoscopes with videolaryngoscopes would be expensive. A McGrath costs about $2500 on eBay, and each new nonreusable blade cover costs about $10. A new GlideScope was $12,745 in 2017. A reconditioned GlideScope costs between $1000 and $10,000 on eBay, and each new nonreusable blade costs $38.
Should a videolaryngoscope replace a direct laryngoscope for all initial intubation attempts? I don’t think so. The majority of intubations are straightforward and are successful with a Miller 2 or a Mac 3 direct laryngoscope. Should a videolaryngoscope be available as a back-up piece of equipment for every intubation? Absolutely. The ASA Difficult Airway Algorithm includes the possible use of a videoscope, and states,
“Consider the relative merits and feasibility of basic management choices: (consider) video-assisted laryngoscopy as an initial approach to intubation.” An anesthesia provider who initiates general anesthesia and intubation without an immediately available videolaryngoscope is in danger of not being able to follow the algorithm. The hospital I work in is stocked with either the GlideScope and the C-MAC both readily available for difficult intubations. The availability of a videolaryngoscope for either a first attempt or for backup attempts to intubate a difficult airway patient is vital.
Difficult airway cases can lead to malpractice claims. A 2009 study published in Anesthesiology showed that 2.3% of 2,211 anesthesia-related deaths in the United States from 1999-2005 were attributable to difficult intubation and failed intubation. A 2019 study from the Anesthesia Closed Claims Project database showed that the 102 difficult intubation closed malpractice claims from 2000 to 2012 included sicker patients (n = 78 of 102), emergency procedures (n = 37 of 102), and non-perioperative locations (n = 23 of 102). Preoperative predictors of difficult tracheal intubation were present in only 76% of the patients. Inappropriate airway management occurred in 71 patients. A “can’t intubate, can’t oxygenate” emergency occurred in 80 of the 102 claims, with a delayed surgical airway occurring in 39% of those cases. The authors wrote, “outcomes remained poor in recent malpractice claims related to difficult tracheal intubation. Inadequate airway planning and judgment errors were contributors to patient harm.”
In conclusion: Difficult intubations are a major anesthesia problem, because of: 1) the difficulty in identifying difficult intubation patients prospectively, 2) the medical comorbidities that occur with difficult airway patients, 3) the medical complications that can occur if difficult airways are mismanaged, 4) the dollar cost of increased healthcare utilization as reported in the Moucharite study, and 5) the potential medical-legal liability risk with each difficult intubation.
SuperMorbidly Obese Patient with a Difficult Airway
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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The Barnes Jewish Hospital, Washington University, St. Louis
Imagine this: You’re an anesthesiologist in the operating room at a busy hospital. Your patient is in mid-surgery, and you receive a call from the Anesthesia Control Tower that the patient’s blood pressure is too low, your blood transfusion replacement is inadequate, and that the patient is in danger. What do you do? How do you feel about all this?
Anesthesiologists at Barnes Jewish Hospital at Washington University in St. Louis, Missouri are studying a novel system they call the Anesthesia Control Tower (ACT). The ACT is a telemedicine-based intraoperative clinical support system. A team led by an attending anesthesiologist uses remote monitoring to provide evidence-based support to anesthesia colleagues in all the operating rooms. The ACT is similar in concept to an air traffic control tower. The clinicians in the Anesthesiology Control Tower, called ACTors, monitor operating rooms (ORs) in real time by following the electronic health records. Just as an air traffic control tower monitors aircraft and delivers information and alerts to the pilots, the ACT communicates with anesthesia providers to assist them in providing safe care.
A press article describing the ACT states: “Surgery is a big insult to the human body. A lot can go wrong. In fact, it does. An estimated 10 to 20 percent of patients who undergo major inpatient surgery experience major complications such as heart attacks, unremitting pain, infections, and blood clots in the weeks to months following their procedures; about two percent are dead within 30 days of surgery. Some of this morbidity and mortality may be preventable through early identification of risk factors and better communication to mitigate risks during the surgery. . . . Air traffic control concepts can predict high risks for healthcare complications and improve decision making.”
A software program used in the ACT is called AlertWatch®. The ACT anesthesiologist (ACTor) watches a monitor displaying the Tower Mode census view (Figure 1 below), which shows an overview of all the patients in the ORs. Alerts or abnormal vital signs and laboratory results are represented by squares and triangles, respectively. Checkmarks indicate alerts that must be addressed by the ACT. The Tower Mode view looks like this (Figure 1):
Figure 1 Census View, Anesthesia Tower
The Tower Mode includes a display for each individual patient (Figure 2 below). The organ systems are labeled with relevant physiologic variables and values. Colors outline each organ, and include normal (green), marginal (yellow), or abnormal function (red). The left side of the display shows patient case information. Information regarding the patient’s medical problems can be accessed by selecting the organ system or laboratory study of interest. The black checkmark at the bottom of the left panel indicates that there is an active alert for the ACT clinicians to address (Figure 2 below):
Clicking on the checkmark opens the case review dialogue, which looks like this (Figure 3):
Figure 3, Case Review Dialogue, Anesthesia Tower
The Anesthesia Control Tower is physically located within the hospital complex, but is remote from the operating rooms. Washington University has expanded the ACT to include the Recovery Control Tower, which provides similar surveillance over patients in the Post Anesthesia Care Unit (PACU).
This photograph below depicts the Anesthesia Control Tower manpower at work at Barnes Jewish Hospital at Washington University in St. Louis:
Monitoring surgeries from the Anesthesiology Control Tower (left to right): Omokhaye M. Higo, MD, vice chair for innovation, Thaddeus Budelier, MD, program manager for the Perioperative Innovation Center, and Bradley A. Fritz, MD, assistant professor of anesthesiology, Washington University Medical School.
Some anesthesiologists were initially skeptical about the ACT idea. But Washington University Anesthesia Chairman Dr. Michael Avidan stated, “Most of the skepticism has evaporated over time as clinicians have perceived that innovation and technology are not threats, but rather enhancements. The conceptualization of our Perioperative Innovation Center is more akin to ‘phone a friend’ than it is to a sinister ‘big brother.’”
Current staffing levels of anesthesia professionals in the United States are inadequate. The shortage of anesthesia professionals, particularly in rural areas, may someday be remedied by a telemedicine system which resembles the ACT. We may someday see anesthesia managed by less highly trained persons in the OR, with an ACTor backing them up by watching from on high.
The goals of this clinical trial are 1) to develop machine-learning algorithms for forecasting perioperative adverse events; 2) to develop a clinical decision support system that suggests interventions based on the algorithms, and 3) to change the paradigm of perioperative care.
Will physicians and patients see the ACT model in the near future? Significant issues regarding the adoption of Anesthesia Control Tower technology include:
Documenting that ACT provides an improvement. A critical barrier for anesthesiologists, hospitals, and policy makers nationwide will be documenting that the ACT demonstrates an improvement in costs, patient outcomes, or patient experience. None of these things are apparent at this time.
Paying for the ACT equipment and the ACTor on duty will be an issue. Additional hardware and software would be required at each hospital. An in-person anesthesiologist is already being paid to do each case, and the ACTor is another level of anesthesia staffing someone is going to have to pay for.
Anesthesiologist opposition. A challenging barriers will be how anesthesiologists perceive systems like the ACT. Anesthesiologists are trained to be vigilant and manage their patients themselves. Having the ACT peering into the operating room, perhaps with a video camera watching the operating room, will likely be unpopular with the anesthesiologists being observed. There may also be concern that data from the ACT could be used against physicians in the event of a malpractice lawsuit. When the topic of the Anesthesia Control Tower was breached, one of my physician anesthesiologist colleagues remarked, “If that system becomes standard, I’m quitting.”
Lack of need for an ACT in ambulatory settings. According to a 2017 study by the Centers for Medicare and Medicaid Services, the majority of surgical procedures in the United States, fully 70 percent, occur in ambulatory surgery centers or offices outside of hospitals. These outpatient procedures are predominantly smaller surgeries conducted on healthier patients. These smaller ambulatory facilities would have no use for the ACT, both because patients are healthier and because the surgical procedures incur less risk and fewer complications. The costs of an ACT in these smaller settings would be unlikely bring any benefit.
Flawed analogy. Air traffic controllers exist to coordinate takeoffs and landings, so planes do not collide with each other in the air or on the runways. In anesthesiology, operating room patients will not collide with each other and do not have traffic issues with each other. Instead, the Anesthesia Control Tower will scrutinize each patient’s data for abnormalities that will predict a pending complication.
The ACT and the algorithms developed through the ACT will likely be a transitional technology. Having one anesthesiologist (the ACTor) overseeing multiple operating rooms will likely be a steppingstone to Artificial Intelligence technology in which a computer oversees the data from each operating room, with the aim to detect and prevent adverse outcomes from developing. The arrival of ChatGPT foreshadows the AI technology about to bloom in healthcare. In the future the anesthesia provider in each operating room will likely be backed up by AI technology enforcing algorithms, rather than being backed up by a human in a control tower. I described this healthcare evolution in my 2019 book Doctor Vita, in which Artificial Intelligence in the form of inexpensive, internet-connected computers took over a California medical center and changed the face of medicine forever.
Improving vigilance and improving outcomes is the ultimate goal of ACT technology. Further data on the Anesthesia Control Tower will be forthcoming. We’ll await the prospective controlled studies, and then we’ll all learn whether or not this technology is an advance to help patients and physicians.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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An astronaut en route to Mars develops severe abdominal pain, nausea, and vomiting. A fellow crew member examines him and finds significant tenderness and guarding in the right lower quadrant of his abdomen. The crew members teleconference with physicians on Earth, with a 20-minute communication delay because of the 140-million mile distance between them. The physicians confirm a probable diagnosis of appendicitis. Because the spaceship is more than 200 days away from Earth, the physicians instruct the crew to proceed with surgery and anesthesia in outer space.
How will astronauts conduct general anesthesia and surgery in outer space? Is an anesthesiologist required on board? Is a surgeon required on board? If the flight crew doesn’t include any physicians, how will the crew proceed to save the astronaut’s life?
Distant space missions, known as exploration class missions (e.g. missions to the Moon and Mars) are planned in the coming decades. Staffing an astronaut/physician as one of the crew members on a mission to Mars is possible, but I have no information that the National Aeronautics and Space Administration (NASA) is grooming a combination astronaut/anesthesiologist at this time. In 2017, NASA created an Integrated Medical Model (IMM) as an evidence-based decision support tool to assess risks and design medical systems for extended space travel. The IMM includes 100 medical conditions that might commonly occur during space flight. Twenty-seven of these 100 conditions would require surgical treatment.
The most significant medical risks for space exploration missions are trauma, hemorrhagic shock, and infections. The risk of a medical emergency in space travel is estimated at one event per 68 person months. For a crew of six on a 900-day mission to Mars and back, at least one medical emergency would be expected. On a mission to Mars, the option of a stat return to Earth is impossible. Telemedicine can provide remote communication for medical consultation. While telecommunication between the Moon and Earth would have delays of only 2 seconds in each direction, for a Mars mission the delay in communications could reach up to 20 minutes in each direction, making real-time telemedicine impractical. The communications delay on a Mars mission would also mean that a surgical robot on board could not be controlled by a surgeon on Earth. The crew must be self-reliant.
Only physically and mentally fit candidates who are able to withstand the stresses of space travel are selected as astronauts. Physically and mentally fit candidates are at low risk for medical or surgical emergencies. But with the recent trend of privately funded space programs (e.g. SpaceX), some members of the general public may be offered the opportunity to experience space travel. Privately funded programs may push boundaries regarding the undesirable health status of candidates traveling into space.
PHYSIOLOGIC CHANGES IN SPACE
To devise safe anesthetic care for outer space, one must first understand the changes in an astronaut’s body during microgravity. The void of outer space provides a lack of barometric pressure, a lack of oxygen, severe extremes of temperature, and dangerous levels of radiation. Spacecraft are equipped with Environmental Control and Life Support Systems (ECLSS) to ensure livable conditions within the space capsule. Weightlessness and microgravity cause marked changes in human physiology, described by systems as follows:
Weightlessness causes a combination of decreased gastric motility and increased gastric acidity. If an astronaut requires general anesthesia, one must assume the patient has a full stomach and is at risk for aspiration.
Respiratory system
Microgravity leads to an increase in respiratory rate and a decrease in tidal volume, resulting in near normal ventilation.
Weightlessness and inactivity cause an increase in bone resorption. Bone density decreases by about 1% per month, which predisposes astronauts to long bone fractures and kidney stones secondary to increased calcium excretion. Prolonged microgravity leads to deconditioning of the muscular system with skeletal muscle atrophy. This is most marked in the lower body, as the legs become “effectively redundant.”
REGIONAL ANESTHESIA VERSUS GENERAL ANESTHESIA
IV fluids
Every anesthetic, regional or general, will require the patient to have an intravenous line, usually in their arm. Astronauts will be trained in the insertion of IV cannulae, and the sampling of blood for diagnostic tests. Storage of prepackaged intravenous fluids can occupy a large volume of precious cargo space. An exploration class mission may require up to 100 liters of IV fluids in case of severe burn injuries. Scientists have developed a system named IVGEN (Intravenous Fluid Generation) to prepare sterile IV normal saline from space station drinking water.
Bubbles in the IV fluids are dangerous, and are filtered out by the system, because bubbles could form air emboli and cause a stroke or a heart attack if they entered the body. Transfusable blood products have a limited shelf life, which makes an onboard blood bank impractical for prolonged space travel. Medical checklists will aim to ensure patient safety and help the astronauts gain familiarity with medical equipment and drugs. Medical kits on board will include a basic vital signs monitor, a mechanical ventilator, an ultrasound machine, suction, airway equipment, and a limited range of drugs with protocols regarding how to use them.
Monitors
Standard patient monitoring would include ECG, non-invasive blood pressure cuff, oxygen saturation, end-tidal CO2, and temperature. Preoperative ultrasound examination can be applied for diagnostic use, the assessment of cardiac function and fluid status, and assistance in visualizing blood vessels for peripheral or central line placement.
REGIONAL ANESTHESIA
A regional technique offers simplicity over general anesthesia, but a successful regional anesthetic requires skill, experience, training, and regular use of such skills. Studies on Earth show that an average of 20 procedures are required to reach a learning curve plateau. A practitioner must be schooled in regional anesthesia techniques on Earth prior to the space flight. The three suggested regional blocks to treat the majority of conditions expected to be encountered in space include femoral, sciatic, and brachial plexus nerve blocks. The blocks would be ultrasound-guided, and there is hope that AI-imbedded ultrasound technology will be available in the future to localize relevant structures such as nerves and blood vessels. The injection of a local anesthetic such as ropivacaine for a regional techniques carries the inherent risk of local anesthetic toxicity. The antidote for local anesthetic toxicity is lipid emulsion, which could occupy valuable space on board, and has a shelf life of only 24 months. Spinal blocks are impractical, as the use of typical hyperbaric local anesthesia such as 0.75% bupivicaine has not been investigated in microgravity to date.
GENERAL ANESTHESIA
General anesthesia has the advantages of a quick and reliable onset. The physiologic changes during microgravity predispose a general anesthesia patient to both aspiration of stomach contents and hypotension due to low intravascular volume. Each general anesthetic would require a preinduction loading with intravenous fluid replacement, followed by a rapid sequence induction and endotracheal intubation. In the absence of gravity, restraints will be required to keep the patient immobile for intubation.
Ketamine
Potent anesthetic gases such as sevoflurane cannot be used in outer space, as vaporizers will not function properly in microgravity. General anesthesia will include intravenous medications only. Ketamine will be the preferred drug of choice for induction of general anesthesia, as spontaneous respiration and cardiovascular stability are maintained. Ketamine induces both a dissociative state and analgesia, and has an extended shelf life of around 20 years in powder form. It’s currently used in remote locations on Earth where there is limited equipment and monitoring (e.g. combat anesthesia in low-income countries). The unpleasant psychomimetic side effects of ketamine are negated by the co-administration of an IV benzodiazepine such as midazolam or Valium. Intravenous atropine will also be administered to minimize the increased oral secretions produced by ketamine.
A muscle relaxant/paralytic drug is recommended to facilitate endotracheal intubation. Succinylcholine will not be used because of its ability to cause hyperkalemia. Rocuronium at a modified rapid sequence dose of 1mg/kg is recommended. A checklist and a PowerPoint presentation on the sequence of drugs and procedures needed to initiate general anesthesia will be available for the astronauts to read prior to and during the administration of general anesthesia. A video laryngoscope will be available, as it is recognized as an easier technique for inexperienced practitioners to complete successful endotracheal intubation. A publication by Komorowski and Fleming, “Intubation after rapid sequence induction performed by non-medical personnel during space exploration missions: a simulation pilot study in a Mars analogue environment,” demonstrated that intubation can be done by non-medical staff with little or no training via instructions from PowerPoint slides.
An intravenous infusion of ketamine is recommended for the maintenance of general anesthesia. Opioids are unlikely to be carried on a spacecraft. It’s likely the analgesic effects of ketamine will be used for acute pain relief. Sugammadex will be available to reverse the neuromuscular blockade from rocuronium, and neuromuscular monitoring will be utilized prior to extubation.
For the appendicitis case introduced in paragraph one, the anesthetic would include the IV loading of 500 ml of normal saline; a rapid sequence intravenous induction of general anesthesia using ketamine, midazolam, atropine, and rocuronium; placement of an endotracheal tube into the patient; and an IV ketamine infusion for the maintenance of anesthesia. Once the patient is anesthetized, the surgery could either proceed as an open abdomen under a sterile surgical canopy, or a laparoscopy with the abdomen remaining closed, depending on the skillset and the surgical equipment available to the surgeon/astronaut on board.
One day an astronaut will perform the first anesthetic on a human in outer space. The astronaut will most likely not be a board-certified anesthesiologist, and he or she will likely follow a PowerPoint slide show demonstrating the sequence of procedures and pharmacology for successful anesthesia. Expect the first anesthetic in space to be a tense, exciting, and dramatic event in the history of medicine.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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I was administering a mock oral board exam to a Stanford first-year anesthesia resident in November 2022, and the young man aced the test. He exceeded the knowledge base and judgement of his peers by a significant margin. After the exam, my co-examiner and I asked him how much medical training he’d had to date. He answered that he’d graduated from medical school, completed a one-year internship, and had been an anesthesia resident for (only) 4 months.
“How do you know so much about anesthesia already?” I asked.
“Almost everything you asked me I knew from keeping up with ACCRAC,” he said.
“What’s ACCRAC?” I asked.
He answered, “I was at Johns Hopkins for an anesthesia rotation, and I met Dr. Jed Wolpaw, one of the Critical Care faculty, who has a website called ACCRAC, which is a collection of anesthesia podcasts.”
ACCRAC stands for “Anesthesia and Critical Care Reviews And Commentary.” Our Stanford resident had listened to the podcasts on Dr. Wolpaw’s website for over one year, and as a result he was wise beyond his age concerning anesthesia information and decision making.
I contacted Dr. Wolpaw and told him the Stanford resident’s success story. I queried him about his website and his podcasts. These were his answers to my questions:
What was your impetus for initially starting ACCRAC? What void in anesthesia education did you identify?
“When I was an intern in Emergency Medicine, I listened to EMRAP (Emergency Medicine Reviews And Perspectives) as did every resident I knew, and many attendings as well. It was a fabulous source of information and learning. When I switched into Anesthesiology, I looked for the equivalent podcast but it didn’t exist. I always had in the back of my mind that someday I might try to start one. When I became an attending and heard our residents asking for audio resources, I knew it was time.”
Why did you choose podcasts rather than a website of written words?
“I wanted something that people could listen to while commuting or working out, something that wouldn’t add a burden to their already busy day. Audio only podcasts are really the only way to do that.”
How do you select your guests?
“I look for interesting articles, or approach people who give talks I find intriguing. I also get lots of proposals from people who are doing interesting things and are interested in coming on the show. And I get tons of emails from listeners requesting certain topics. I can’t do them all, but I try to get to as many as possible.”
What percentage of your guests are from Johns Hopkins?
“I’m not sure of the exact number but certainly a fair amount, I’d guess maybe 70% or so.”
Is your target market residents and fellows? How about university professors, or community anesthesiologists?
“I certainly think we have a lot of content that is useful to trainees, but we also have a large number of practicing anesthesiologists, both academic and private practice, who listen (and some use it for CME) as well as nurses, CRNAs, AAs, medical students and others.”
Is any aspect of ACCRAC directed toward laypeople?
You trained at UCSF, arguably the nation’s finest anesthesia program. How does Hopkins compare to UCSF? Is there a West Coast-East Coast difference?
“I think they are both fabulous programs. I honestly find more similarities than differences and apart from the weather haven’t noticed much of a coastal difference.”
What are 5 or 6 of your favorite podcasts, to direct my readers to?
How labor-intensive is it to maintain and add to ACCRAC? I notice six other individuals on your home page who assist you.
“It’s a fair amount of work, but I really enjoy it. I’m lucky to have volunteers who handle the social media accounts and help with the website. For now the preparation, interviews, recording, and editing is all me but it’s manageable.”
I see that you published “Podcasting as a Learning Tool in Medical Education: Prior to and During the Pandemic Period,” a reference regarding podcasting. To what extent do you see podcasting growing in medical anesthesia?
“I think we’ll see significant growth. Emergency Medicine is a great example where there are podcasts covering all sorts of sub-specialty topics and niche interests. We’re already starting to see some growth in Anesthesiology with great podcasts like Depth of Anesthesia and I think we’ll continue to see more.”
****
Googling the topic of “anesthesia podcasts” reveals Dr. Wolpaw’s website on the first page. Other leading sources of anesthesia podcasts include:
The American Society of Anesthesiology (ASA) presents four categories of podcasts, including (1) ASA’s Central Line, which “features leaders in our field discussing a wide variety of challenges and opportunities vital to our practice and our profession.” (2) Residents in a Room, “a podcast series for residents, by residents, featuring anesthesiologists-in-training from across the country, putting it all out there, discussing their hopes, fears and expectations for residency and beyond.” (3) ANESTHESIOLOGY featuring the “Editor-in-Chief of Anesthesiology and his monthly overview of new journal content (translated in multiple languages) and featured author podcasts that highlight research through author and editorialist interviews; (4) Summaries of Emerging Evidence (SEE), featuring “a sneak peek of the most interesting studies covered the latest edition of the popular continuing education program.”
Podcasts present a significant means of communication, information, and entertainment in the United States. Per The Infinite Dial report by Edison Research and Triton Digital, “As of 2021, 41% of Americans ages 12 or older have listened to a podcast in the past month, . . . up from 37% in 2020 and just 9% in 2008. Additionally, 28% of those 12 and older said they have listened to a podcast in the last week, up from 24% in 2020 and 7% when this was first measured in 2013.” Per Pew Research Center, “About a quarter of U.S. adults (23%) say they get news at least sometimes from podcasts.
“By entering a query for the term “podcast” in PubMed, a year-by-year breakdown of the number of publications with this term in the title shows an increasing trend from 2006 to 2022.”
“For the creator, podcasting is a relatively low-cost endeavor, allowing for a low bar for entry into the podcasting space.A feasibility study conducted for the creation of an ophthalmology podcast revealed that start-up costs were just $212.18 with $29 monthly expenses.”
“One review found that listeners find learning from podcasts to either be equivalent to, or better than, classroom learning.”
“Multiple studies have found that listeners of medical education podcasts felt more motivated to learn.”
“Rather than waiting on peer-reviewed literature, which could take several months to begin to show up, the rapidly evolving nature of the early pandemic required a faster means of propagating information to clinicians. Podcasts were a way by which-as early as February and March of 2020-anecdotal experiences from physicians across the world could be shared before peer-reviewed literature could be published.”
I find the primary advantage of podcasts is that one can listen to them while multitasking. I find a disadvantage in that, unlike a written article, one cannot skim over the content looking for the most pertinent sentences or paragraphs. If a podcast lasts 20 minutes, you’re committed to listening to every word, or to utilizing an available fast forward button for a 30 second leap to a later time. Another disadvantage is the inability to visually display internet links to references. With a written article, one can click on links to other published articles mentioned in the text. Dr. Wolpaw’s publication states that “many podcasts in medical education also utilize show notes-summary documents that accompany podcast episodes. These documents outline the episode’s main points and contain references to resources discussed in each episode.”
Podcasts are mainstays of 21st century media. The freedom to educate yourself while driving a car, doing chores, or exercising is a terrific opportunity for medical professionals. Until I discovered ACCRAC, I was not a podcast listener. Now I am, and I recommend the same to you. Podcasts won’t replace the written words of anesthesia textbooks or journals, but podcasts can be enjoyable and informative, and they have a definite role in supplementing medical education.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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The most important recommendations from these ASA Practice Guidelines, each backed by Strong Strength of Recommendation (bold text by me) are:
When neuromuscular blocking drugs are administered, we recommend against clinical assessment alone to avoid residual neuromuscular blockade, due to the insensitivity of the assessment.
We recommend quantitative monitoring over qualitative assessment to avoid residual neuromuscular blockade. When using quantitative monitoring, we recommend confirming a train-of-four ratio greater than or equal to 0.9 before extubation.
We recommend using the adductor pollicis muscle for neuromuscular monitoring.
We recommend against using eye muscles for neuromuscular monitoring.
We recommend sugammadex over neostigmine at deep, moderate, and shallow depths of neuromuscular blockade induced by rocuronium or vecuronium, to avoid residual neuro- muscular blockade.
What type of quantitative NM monitoring device should we aim to acquire? There are three types of quantitative monitors of neuromuscular blockade discussed in a 2021 Anesthesiology editorial. I quote from this reference:
1. Acceleromyography. Depolarization of the ulnar nerve results in contraction of the adductor pollicis, which flexes the thumb, producing an acceleration detected by the sensor. . . . the thumb must be entirely free to move, which precludes monitoring the hand that has been tucked at the patient’s side during surgery. The second problem is that the baseline, unparalyzed train-of-four ratio (the ratio of the fourth to the first twitch of a train-of-four), which should theoretically be equal to 1, is often greater than 1.
Acceleromyography monitoring
2. A mechanomyograph is an instrument that directly measures the isometric force of contraction of the thumb, using a force transducer. . . . A mechanomyograph is a somewhat cumbersome instrument that has been used primarily for research, and very seldom for routine clinical practice. Currently, mechanomyography is not commercially available.
3. Electromyography directly measures the compound action potential of the adductor pollicis muscle. . . No movement is required for this measurement to be made. The hand can be tucked at the patient’s side without any significant effect on the electromyogram. . . . A baseline, unparalyzed train-of-four ratio is not required.
electromyography (EMG)
Electromyography (EMG) is the most promising of the three devices. The Nemes et al study, performed in Hungary, established that EMG compares favorably to acceleromyography, stating, “The EMG-based device is a better indicator of adequate recovery from neuromuscular block and readiness for safe tracheal extubation than the acceleromyography monitor.” The Nemes study utilized an EMG called a TetraGraph.
Where can you buy a TetraGraph? A Google search for this device leads us to a website for a company called Senzime.
TetraGraph and TetraSens EMG unit
The TetraGraph received FDA 510 clearance in 2019. Dr. Sorin J. Brull, the author of the Anesthesiology editorial on the 2023 NM Practice Guidelines, is a principal, shareholder, and the Chief Medical Officer in Senzime, as well as a Professor Emeritus of Anesthesiology and Perioperative Medicine at the Mayo Clinic.
I contacted a representative of Senzime, who demonstrated the device to me. I learned the following:
Senzime’s TetraGraph is manufactured in Sweden. The device has been improved and modified over the past 3 years.
The TetraGraph NM monitoring device clamps to an IV pole, and is slightly larger than an iPhone. A disposable TetraSens sticker of sensing electrodes attaches to the patient’s wrist over the ulnar nerve, and extends distally to adhere to the skin over either the pinky or the thumb. The hand can be tucked out of sight and the EMG technology will still reveal accurate data.
The Tetragraph attaches to the TetraSens via a cable.
The Tetragraph screen displays a button labelled “AUTO,” which will activate serial trains-of-four at a preselected interval, for example, every 20 seconds.
The screen on the device is usually set to display four bars in a bar graph, representing the measured EMG amplitude of the train of four. At control the quantitative NM score will be 100%, as all four twitches are equivalent. Once a muscle relaxant is administered to the patient, the bar graph will change, showing decreased heights of the bars dependent on the dose and time of the muscle relaxant.
TetraGraph bar graph screen depicting Train-of-Four
The anesthesiologist should wait until the quantitative NM score is 90% or greater, prior to extubation.
The hardware retails for $2000 – $2500 per unit. The disposable stickers that adhere to the patient’s hand are $20 each. The unit can be annexed to certain patient monitoring systems, and data can be input into an Electronic Medical Record system. Senzime’s website https://senzime.com/about-us/ceo-statement/ outlines the company’s intention to combine TetraGraph with Masimo’s patient monitoring system, stating “Our ambition is to submit the module developed to connect TetraGraph® with Masimo’s patient monitoring system Root® for approval at the end of 2023, and to launch at the beginning of 2024.”
To date Senzime has sold 300+ units in the United States. Several large hospital systems, including the University of Arizona, Duke, University of North Carolina, and the Medical College of Wisconsin have purchased the devices for their operating rooms. Multiple other large hospital systems are on the verge of completing purchases of 100-200 units as of January 2023. Senzime has an inventory to accommodate such purchases, and a clinical team positioned to help medical centers or surgery centers try out and/or adopt the technology.
Will Senzime have a monopoly or near-monopoly on this new technology? Time will tell. A Google search for “quantitative neuromuscular monitoring device” yields only a few companies competing with Senzime, including: TwitchView by Blink, Xavant, and GE Healthcare.
STANDARD OF CARE?
Are the 2023 ASA Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade now a standard of care for practicing anesthesiology?
No. Guidelines are not Standards.
In these 2023 Practice Guidelines, the ASA states, “Practice guidelines are systematically developed recommendations that assist the practitioner and patient in making decisions about health care. . . . practice guidelines developed by the American Society of Anesthesiologists are not intended as standards or absolute requirements, and their use cannot guarantee any specific outcome.”
Expect quantitative NM monitors to become available where you work. Expect most hospitals to purchase these devices. What will you do until quantitative NM monitors become available where you work?
1. Since clinical assessment alone to avoid residual neuromuscular blockade is inaccurate, I believe a qualitative NM monitor is better than no NM monitor.
Qualitative Twitch Monitor
2. Monitoring twitch at the adductor pollicis at the wrist is more accurate than monitoring the periocular muscles, so apply your qualitative twitch monitor to the wrist.
4. Following a general anesthetic, don’t leave your patient’s side in the PACU until you are certain that their airway is open and they are breathing adequately without any sign of residual respiratory difficulty.
Until your hospital and your surgery centers supply you with quantitative neuromuscular EMG monitors, be aware of the recommendations of the 2023 ASA Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade, and comply with them as best as you can. When quantitative NM units arrive, I encourage you to use them. The device I tested was quick to apply, easy to use, and provided valuable information to assure patient wellbeing.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Ciprofol is a new intravenous (IV) anesthetic agent which is undergoing early clinical trials in China, and may become a significant tool in our anesthesia armamentarium if and when the drug is approved by the Food and Drug Administration (FDA) in the United States. Ciprofol has a chemical structure similar to propofol. Because of its rapid onset and rapid offset profile, propofol is currently the most used IV anesthetic drug in the world. Propofol is used for surgical anesthesia, procedural sedation, and intensive care unit (ICU) sedation. Propofol was FDA-approved in the United States in 1986 and is now off patent. Generic propofol is inexpensive, averaging about $2.27 for a 20 ml vial. Limitations of propofol include (a) respiratory depression, such that it can only be used by physicians who are expert in airway management (e.g. anesthesiologists, CRNAs, and emergency room doctors); (b) hemodynamic depression in some elderly or sick patients; (c) pain on injection; and (d) the propofol infusion syndrome (PIS) which can lead to hyperkalemia and cardiac arrest in ICU patients after prolonged exposure to propofol infusions.
The chemical formula of ciprofol is similar to propofol, but with single R-configured diastereoisomers.
Ciprofol is about 5 times more potent than propofol. Like propofol, ciprofol is formulated in a lipid emulsion with a drug concentration of 10 mg/mL. Let’s review the published literature on ciprofol to date. All of the following studies were done in China:
Phase 1 trials (small groups of subjects are given a single dose of the drug, and are observed and tested for a period of time to confirm safety):
Teng et al. (2021) conducted a phase I trial which demonstrated that a ciprofol dosing regimen of 0.4-0.9 mg/kg was well-tolerated and exhibited rapid onset and recovery properties. Peak plasma concentration occurred 2 minutes after injection, and all subjects recovered fully after ciprofol administration, with the shortest time being 9.2 minutes in the 0.4 mg/kg group.
Liu et al. (2021) conducted a phase II trial which involved 36 ICU patients who were on mechanical ventilation. A remifentanil infusion of 0.02–0.15 μg·kg−1·min−1 plus either ciprofol or propofol were used for analgesia and sedation. The ciprofol loading dose was 0.1–0.2 mg/kg with a maintenance infusion rate of 0.3 mg/kg/h. The propofol loading was at 0.5–1.0 mg/kg, with a maintenance infusion rate of 1.5 mg/kg/h. The tolerability, sedation characteristics, and adverse events such as hypotension were comparable between both groups. The authors concluded that “ciprofol is comparable to propofol with good tolerance and efficacy for sedation of Chinese intensive care unit patients undergoing mechanical ventilation in the present study setting.”
The propofol infusion syndrome (PIS) is a potentially lethal syndrome that occurs due to prolonged infusion described in adults and pediatric ICU patients who are on mechanical ventilation. To date, published studies have not administered multi-day infusions of ciprofol to mechanically ventilated ICU patients to determine whether there is anything similar to PIS with ciprofol.
Wu et al. (2022) published a single-center trial on 92 patients titled “Efficacy and safety of ciprofol-remifentanil versus propofol-remifentanil during fiberoptic bronchoscopy.” Fentanyl (50 μg) was given to all patient 2 minutes before the intravenous administration of either 0.3 mg/kg of ciprofol or 1.2 mg/kg of propofol, followed by a remifentanil infusion in both groups. Top-up doses of one-third to one-fourth of the initial dose of ciprofol or propofol were repeated at 2-minute intervals as needed. The two drugs were comparable. The authors concluded that “ciprofol-remifentanil was non-inferior to propofol-remifentanil with regard to successful sedation for flexible bronchoscopy.” Systolic, diastolic, and mean blood pressures declined significantly less in the ciprofol-remifentanil group (p < 0.05). There was no difference in respiratory depression between the two groups, and the only statistical difference in adverse effects was a decrease in pain on injection for ciprofol over propofol (p=.001).
Chen et al. (2022) compared ciprofol and propofol in 120 women for the induction of anesthesia in gynecologic surgery. Intravenous midazolam (0.03 mg/kg) and sufentanil (0.3 μg/kg) were administered initially, followed by ciprofol (0.4 mg/kg) or propofol (2 mg/kg). After the loss of consciousness, rocuronium (0.6 mg/kg) was administered and endotracheal intubation was performed. Within the initial 10 minutes following study drug administration, blood pressure declined significantly less in the ciprofol group than in the propofol group. The authors concluded that “ciprofol was associated with slightly less pronounced effects on the cardiovascular system.” The incidence of injection pain was higher in the propofol group than in the ciprofol group (58% vs 16%, p < 0.001).
Lan et al. (2022) randomized 150 patients to ciprofol or propofol for hysteroscopy. All patients received intravenous sufentanil 0.1 μg/kg IV initially. Ciprofol patients then received an induction dose of 0.4 mg/kg and a maintenance dosage of 1.0 mg/kg/h. Propofol patients received an induction dose of 2.0 mg/kg and a maintenance dosage of 5.0 mg/kg/h. After the sedative administration, the systolic, diastolic, and mean pressures all dropped significantly lower in the propofol group than in the ciprofol group. During the procedure, 2/75 ciprofol patients vs 17/75 propofol patients required an airway intervention such as a chin-lift or jaw-thrust maneuver (p< 0.05). The authors concluded that “the lower level of respiratory depression seen with ciprofol makes this drug more suitable and safer than propofol for hysteroscopic procedures.”
Phase III trials (randomized controlled multicenter trials on larger patient groups, aimed at determining how effective the drug is in comparison with the current “gold standard” treatment, i.e. propofol):
Li et al. (2022) conducted a phase III study at ten teaching hospitals, comparing ciprofol and propofol for deep sedation for colonoscopy or gastroscopy. A total of 289 patients were studied. Each patient received 50 μg fentanyl 1 minute before the intravenous infusion of either ciprofol (0.4 mg/kg) or propofol (1.5 mg/kg). Up to five top-up doses of 1/2 the initial dose were given upon signs of inadequate sedation, and repeated at 2-minute intervals as required. The mean time for a patient to become fully alert after the procedure was 3.3 minutes in the ciprofol group vs. 2.0 minutes for the propofol group (P < 0.001). The time to discharge was 7.4 minutes for the ciprofol group vs. 6.0 minutes for the propofol group (P < 0.001). Nine patients (6.3%) in the ciprofol group and 15 patients (10.3%) in the propofol group had respiratory events (respiratory depression, apnea, or hypoxemia), all of which were mild or moderate in severity. The authors concluded that “at a dose of 0.4 mg/kg for deep sedation, ciprofol was non-inferior to 1.5 mg/kg propofol in the success rate of gastroscopy and colonoscopy and exhibited a good safety profile.”
MY TAKE: WILL CIPROFOL BE A SUCCESSFUL ADDITION TO OUR IV ANESTHESIA DRUG ARSENAL?
It depends.
If ciprofol and propofol were cost-equivalent, ciprofol would gain some market share, and might prove to be a superior drug to propofol. However, when and if it is FDA-approved in the United States, ciprofol will cost significantly more than propofol because ciprofol will be on patent. Hospitals and surgery centers will be reluctant to pay more for the drug unless there are proven advantages. Ciprofol appears to have significantly less pain on injection when compared to propofol, but pain on injection with propofol is not a major issue. Pain on injection does not lead to any long term adverse outcomes, and the pain can be blocked by injecting IV lidocaine immediately prior the initial dose of IV propofol.
The data that ciprofol leads to less blood pressure decreases than propofol shows only a mild difference—too small an advantage to mandate replacing propofol with ciprofol for that reason alone.
So far there are no data to confirm or deny that there is any equivalent to propofol infusion syndrome with ciprofol. If there is no prolonged infusion syndrome, then ciprofol may find a market for ICU sedation of mechanically ventilated patients.
Overall, I believe ciprofol must promise a lack of respiratory depression if the new drug is to capture any of propofol’s market share for procedural sedation/surgical anesthesia. The most bothersome issue with propofol is the risk of respiratory depression, which requires an anesthesia professional or airway expert administer the drug. If a patient is oversedated with propofol, that patient may stop breathing or have upper airway obstructed breathing, which can lead to hypoxia, cardiac arrest, and anoxic brain damage. The FDA warnings for propofol include:
For general anesthesia or monitored anesthesia care (MAC) sedation, DIPRIVAN Injectable Emulsion should be administered only by persons trained in the administration of general anesthesia and not involved in the conduct of the surgical/diagnostic procedure. Sedated patients should be continuously monitored, and facilities for maintenance of a patent airway, providing artificial ventilation, administering supplemental oxygen, and instituting cardiovascular resuscitation must be immediately available. Patients should be continuously monitored for early signs of hypotension, apnea, airway obstruction, and/or oxygen desaturation. These cardiorespiratory effects are more likely to occur following rapid bolus administration, especially in the elderly, debilitated, or ASA-PS III or IV patients.
In the Li study above, 6.3% of the ciprofol patients had mild to moderate respiratory adverse events when sedated for GI endoscopy. While the 6.3% rate is lower than the 10.3% rate for the propofol patients, the non-zero incidence of respiratory events with ciprofol in this one study points to an anesthesia professional still needing to be present if ciprofol is administered for endoscopy.
In the Lan study above, during IV sedation only 2/75 ciprofol patients, compared with 17/75 propofol patients, required airway intervention such as with a chin-lift or a jaw-thrust maneuver during hysteroscopy (p< 0.05). This lower incidence of required airway intervention is encouraging, but the incidence is still not zero, and we’ll need more data to document the respiratory risks of ciprofol.
If ciprofol sedation is found to NOT produce any significant respiratory depression, apnea, or upper airway obstruction (therefore less risk of hypoxia and anoxic brain damage), this would be a profound advance over propofol. Then ciprofol could be administered for procedural sedation, e.g. for gastroenteroscopy, without an anesthesia airway expert attending to the patient. There is insufficient studies to date to know whether this will be true or not.
My guess? After all the data is in, ciprofol will cause a non-zero incidence of respiratory depression, and therefore a non-zero risk of hypoxia and anoxic brain damage, so an anesthesia airway expert will be necessary to administer the drug. The advantage of ciprofol’s lower but non-zero incidence of required airway intervention will not be a major advance in the hands of anesthesia professionals. The higher cost of ciprofol will preclude the decision of hospitals and surgery centers to switch to ciprofol until the new drug is off patent.
We’ll have to wait for more data on ciprofol, but don’t be surprised if propofol remains on top of the intravenous sedative/hypnotic anesthesia drug pedestal after the studies are concluded.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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In a previous column I advised examinees how to best prepare for the Standardized Oral Exam, and how to best perform on the exam. In this column I’ll outline how to set up a Mock Oral Exam program.
The pass rate for the Standardized Oral Exam is approximately 88%. By subtraction, about 12% of candidates fail the SOE.
SOE (Standardized Oral Exam) pass rates for the American Board of Anesthesiology 2017 – 2021
I believe all candidates can benefit from taking Mock Oral Exams before they take the ABA test. I took my initial Mock Oral as a first-year resident in 1984 and I failed, botching the management of a difficult airway by performing a tracheostomy too soon. I took two Mock Orals each year after that and passed the ABA Oral Exam on my first attempt. I can attest that Mock Orals are an effective simulation to prepare for the ABA exam. One can search online and find books and prep classes to prepare for the Standardized Oral Board Exam, but the only way to rehearse verbal skills for an oral exam is take practice oral exams. It’s within the resources of every anesthesia residency program to provide Mock Oral Exams for their trainees. As an examiner I’ve administered Mock Oral Exams to over 100 residents since 1989. The recipe on how to set up such a program follows below:
SCHEDULING MOCK ORAL EXAMS
Assume a residency program has 10 residents in each year, for a total number of 30 residents. On three separate evenings in November, set up Mock Oral Exams for the first year, second year, and third year residents. Provide an equal number of examiners as you have examinees. Group the examiners in pairs and send each pair to a separate office room in your hospital headquarters. For example:
November 28th. First year resident exams from 1700 hours – 1735 hours, and from 1745 hours – 1820 hours. At 1700 hours the team of Faculty Member A and Faculty Member B will examine Resident Alpha. At the same time, in four adjoining rooms four other pairs of faculty members will examine four additional residents. At 1745 hours Faculty Member A and Faculty Member B will examine Resident Beta with the same exam question. The same format is followed in the four adjoining rooms, testing a total of ten first year residents.
November 29th. Second Year Resident exams from 1700 hours – 1735 hours, and from 1745 hours – 1820 hours. The same staffing as November 28th is repeated. The examiners may be different. The exam questions are more difficult, given that the residents are one year further in their training.
November 30th. ThirdYear Resident exams from 1700 hours – 1735 hours, and from 1745 hours – 1820 hours. The same staffing as November 28th is repeated. The examiners may be different. The exam questions are more difficult than on November 28th or 29th, given that the residents are in the last year of their residency training.
In May of the same academic year the exam sequence as above is repeated, giving each resident their second Mock Oral in the same training year. Each Mock Oral Exam lasts 35 minutes. The first 25 minutes will be questions about a hypothetical patient. The first examiner (e.g. Faculty Member A) begins by asking 10 minutes of questions dealing with preoperative anesthesia issues, followed by 15 minutes of questions about intraoperative issues by the second examiner (e.g. Faculty Member B), and in the final 10 minutes Faculty Member A asks questions about three completely different patients with assorted anesthesia dilemmas.
SAMPLE MOCK ORAL TEST STEM:
An example of a Second Year Resident Mock Oral Board stem follows:
A 50-year-old man with hypertension, diabetes, obesity, and obstructive sleep apnea presents for an emergency surgery for a small bowel obstruction. He has been vomiting and unable to eat or pass gas for 12 hours. He has 8/10 pain in the abdomen. His medications are hydrochlorothiazide for hypertension, last taken 24 hours prior to admission, and a continuous insulin pump which he stopped 10 hours ago. He is 5 feet 6 inches tall and weighs 100 kg for a BMI=35. His pulse=120 beats per minute, blood pressure=170/105, oxygen saturation on room air=96%, respiratory rate=24 breaths per minute, and temperature=98.6.
Physical exam: He is doubled over in abdominal pain and looks exhausted. His airway shows a thick neck circumference of 18 inches and a full beard. Except for tachycardia he has normal cardiac and lung exams. His abdomen is distended, and he has rebound abdominal tenderness and hyperactive bowel sounds. His labs are normal except for a glucose = 455 mg/dL and a potassium = 3.0 mEq/L. His ECG shows normal sinus rhythm. His chest X-ray is normal.
The script given to Faculty Member A reads as follows:
10 MINUTES – INTRAOPERATIVE MANAGEMENT
Blood glucose. How would you manage his blood glucose level? What would be your target glucose concentration? How would you administer insulin? How do you administer U-100 insulin? How would hypoglycemia present during general anesthesia?
Monitoring. Does this patient require invasive monitoring? Would you place an arterial line prior to induction? Why? Is a CVP necessary? Why or why not? Would you use a pulmonary artery catheter? What about TE echo?
Airway management. How would you manage the airway? Would you do an awake intubation? How would you do this? Would you do a rapid sequence induction? Which muscle relaxant would you use? Why? Assume you do a rapid sequence induction and you cannot see the vocal cords. What do you do? What if you cannot intubate the patient and you cannot ventilate the patient with a mask?
Potassium management. Will you administer potassium? Why? How fast would you give potassium? What are the risks of a low potassium during anesthesia? What are the risks of a high potassium concentration during replacement?
Choice of anesthetic. What will be your plan for anesthetic maintenance? What are the advantages ofinhaled anesthesia? Of total intravenous anesthesia? Which would you choose and why? Is there a role for regional anesthesia for this case? Why or why not?
The script given to Faculty Member B reads as follows:
15 MINUTES – POSTOPERATIVE MANAGEMENT
Extubation. Would you extubate the patient following the surgery? What would be your criteria for extubation? You decide to extubate the patient in the operating room. Immediately following extubation, his oxygen saturation falls to 80%. What is your differential diagnosis? How would you manage the situation?
Arrythmia. On arrival to the ICU the patient’s heart rate increases to 150. How would you evaluate? Assume the blood pressure is 110/70. What therapeutic measures would you take? Assume blood pressure is 70/40. What therapeutic measures would you take?
Oliguria. Assume the cardiac status is stabilized. The patient makes 80 ml of urine over the first two hours postoperatively. What is your differential diagnosis? What tests could you order? Why? Would you give a fluid bolus? Would you give a diuretic? Why?
Chest pain. Assume the patient is extubated on arrival to the ICU. He complains of upper abdominal/mid chest pain. How would you evaluate? What is your differential diagnosis? What tests would you order? How would you manage the situation?
Postoperative pain. Assume no heart abnormalities are found. The patient is complaining of abdominal pain after surgery. How would you manage pain control?
The final script for Faculty Member A reads as follows:
10 MINUTES – ADDITIONAL TOPICS
Pediatric open eye, full stomach. A 5-year-old child presents with an open eye injury due to a fall against a sharp table corner. She needs emergency surgery to save her eyesight. She ate a McDonalds Happy Meal two hours ago, but the ophthalmologist says the surgical repair cannot wait. The child will not let you start an IV while she is awake. How would you induce anesthesia? Would you consider a mask induction? Would you consider an intramuscular induction? How would you deal with the full stomach? How would you proceed? The child vomits during induction. How would you manage this?
Morbidly obese patient for C-section. A 30-year-old woman presents in labor at 39 weeks. She is morbidly obese with a BMI=42. Her obstetrician decides the patient needs an urgent Cesarean section because of late decelerations on the fetal heart monitor. Would you choose regional anesthesia or general? Why? You attempt to place an epidural but get a wet tap. What would you do? If you had to administer a general anesthetic, how would you proceed?
Family history of malignant hyperthermia. A 17-year-old boy with a tonsillar abscess presents for tonsillectomy. His uncle had a history of dying from malignant hyperthermia after tonsillectomy. Is this case appropriate for a freestanding outpatient surgery center? Would you delay the case? Would you order any preoperative tests? The surgeon says the case is urgent. What is your anesthetic plan?
At the conclusion of the 35-minute Mock Oral exam, the two examiners will stop. At this time the examiners discuss the performance with the resident examinee. This conversation includes:
Asking the resident how they felt they did.
Discussing whether the resident made any anesthetic decisions that were unsafe, i.e. made the patient’s condition worse, or that led to a poor outcome.
Discussing whether the resident answered the questions by describingwhat he or she would do. (This is the key to succeeding in oral examinations.)
Discussing the resident’s communication and presentation skills, i.e. did they have effective eye contact, a confident speaking tone, and acceptable body language?
Discussing whether the resident projected a fund of knowledge acceptable for their level of training.
Advice to Faculty Examiners on how to best perform a Mock Oral Exam:
If you know the examinee personally, conduct the exam as if this was the first time you’d met them, i.e. they are “Dr. Examinee,” not “Justin,” or “Jennifer.”
Read each question within the stem to the examinee, and listen to how they answer. Your job is to assess the examinee’s expertise in managing challenging anesthesia circumstances. If their answer is correct, quickly move on to the next question so you can test them on a new aspect of the patient care.
Anytime an examinee introduces a new drug or a new test or a new fact into their answer, consider digging deeper by asking, “What is _____? What do you know about ____?”
Don’t give immediate feedback after an answer by saying “OK.” Don’t reveal correct answers to the examinee during the exam.
The examinee should not be asking you questions. If you are asked a question, deflect it by re-asking your previous question.
Interject unexpected complications into each patient management, e.g. the blood pressure rises markedly or falls markedly, the pulse rate rises markedly or falls markedly, the oxygen saturation falls markedly. Find out what the examinee’s answer is in terms of differential diagnosis of the cause, and what their action(s) would be to correct the complication.
Evaluate whether the examinee manages anesthesia and complications safely.
Include a management of a difficult airway situation. The quickest way for an examinee to fail an oral exam is to lose an airway.
The purpose of the three extra cases in the last 10 minutes of the exam is to assess the examinee’s performance in areas that weren’t covered by the stem question, i.e. to round out the examination of pediatric, neuro, obstetric, cardiothoracic, pain, or regional anesthesia knowledge.
Pay attention to the examinee’s body language, their eye contact, the confidence of their verbal answers, and their fund of medical knowledge. Does the candidate speak and answer like a consultant in anesthesiology would?
Image from a videotape of Mock Oral Exams at the University of North Carolina Department of Anesthesiology
Writing Mock Oral Questions is not difficult. Performing the role of an examiner is not difficult. Prior to the exam, faculty examiners can look up the answers after reading through the questions, if they don’t know that specific area of anesthesia knowledge.
Beyond the role of faculty members providing a Mock Oral Exam program, it’s also possible for examinees to prepare and give Mock Oral Exams to each other on their own time, as an opportunity for practicing and honing their verbal answering skills.
I recommend a Mock Oral Exam program as a key step toward passing the ABA Standardized Oral Exam, and toward becoming a board-certified consultant.
in our field. As stated above, the only way to rehearse the verbal skills necessary for an oral exam is take practice oral exams. Good luck!
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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The audit trail is NOT part of the EMR printout, and it’s not visible on the EMR patient care screen that we healthcare providers see. Lawyers can subpoena the audit trail in malpractice legislation, and the hospital must provide the audit trail if the court decides that the audit trail is relevant. An audit trail will look like an Excel document, with the provider’s name in one column and the information about each click listed in other columns:
In any malpractice legislation, an attorney will most likely have to hire an expert to interpret this audit trail for the judge and jury to understand what the document illustrates.
The audit trail was mandated by the 2005 Security Rule of the Health Insurance Portability and Accountability Act (HIPAA), which required all healthcare organizations to “implement hardware, software, and/or procedural mechanisms that record and examine activity in information systems that contain or use electronic protected health information.” Any organization that works with electronic protected health information—which includes patient names, addresses, social security numbers, and other pieces of sensitive personal information—must use audit trails. The purpose of the audit trail was to detect inappropriate viewing of the EMR by someone who was not directly caring for the patient. For example, preventing a healthcare provider from clicking on the EMR of someone else’s patient who is a neighbor, a previous girlfriend, a celebrity athlete, politician, or entertainer. But an audit trail is a roadmap to a physician’s EMR use, and in the case of a malpractice lawsuit, the audit trail can be either redeeming or damning.
Back in the era of handwritten medical records, Samuel Shem described “buffing the chart” in his medical satire novel “The House of God.”
“Buffing the chart” was a dishonest means of writing medical notes in a patient’s chart to make the patient look well-treated, without the doctor providing that treatment. Buffing the chart, or any other dishonesty, is impossible with EMRs. The audit trail will document whether you provided standard medical care in real time or not. If your patient has a significant complication or an adverse outcome, a lawyer can subpoena the audit trail and hire an expert to interpret it.
Indeed, the most common use of audit trails is in medical malpractice actions. Let’s look at some hypothetical examples:
An 8-year-old patient is scheduled for a tonsillectomy. The patient suffers an acute cardiac arrest fifteen minutes after the induction of general anesthesia. Despite all Advanced Cardiac Life Support measures, the patient dies. The EMR shows standard of care anesthetic management. The family sues for wrongful death, and the plaintiff attorney orders an audit trail. The audit trail documents that one hour after the unsuccessful Code Blue, the anesthesiologist reentered the EMR and deleted the administration of “succinylcholine 50 mg” as the administered muscle relaxant and substituted “rocuronium 20 mg.” This audit trail finding is a “smoking gun” that explains the cardiac arrest. (The Food and Drug Administration posts a Black Box Warning against using succinylcholine for elective pediatric surgery, because patients with occult myotonic dystrophies can suffer acute hyperkalemic cardiac arrest if they receive succinylcholine.) The anesthesiologist loses the malpractice suit.
A 36-year-old woman is scheduled for emergency surgery at 3 a.m. for an ectopic pregnancy. The patient weighs 250 pounds and is 5 feet tall, for a Body Mass Index (BMI) = 48.8. On induction of general anesthesia, the anesthesiologist working alone is unable to successfully place an endotracheal breathing tube and is unable to ventilate oxygen into the patient. The patient develops anoxic brain damage. The family sues the anesthesiologist, and the plaintiff attorney orders an audit trail. The audit trail documents that the anesthesiologist never clicked on an available old anesthetic record which documented that this patient had a difficult airway, in which it took two anesthesiologists twenty minutes to successfully insert an endotracheal breathing tube using both a GlideScope and a fiberoptic laryngoscope. The audit trail also documents that one day after the surgery, the anesthesiologist added a paragraph to his preoperative note claiming that he was aware of the previous difficult airway diagnosis. Once the audit trail results were revealed, the anesthesiologist and his defense lawyer realize that they cannot win, and they pay a malpractice settlement out of court.
A 55-year-old man is scheduled for a left hip replacement. His past medical history is significant only for hyperlipidemia. The EMR shows standard of care anesthetic management for the surgery, but in the Post Anesthesia Care Unit (PACU) the patient develops shortness of breath, chest pain, and needs to be reintubated and sent to the Intensive Care Unit. Cardiologists diagnose an acute myocardial infarction (MI) and congestive heart failure. The patient survives, but the MI leaves the patient with reduced cardiac output and chronic heart failure. The patient sues, and the plaintiff attorney orders an audit trail. The audit trail reveals that the anesthesiologist never looked at the preoperative ECG which showed ischemic changes. The standard of care following this abnormal ECG required a cardiology consult prior to the elective surgery. The plaintiff wins the case as the anesthesiologist and the primary care doctor failed to make the required referral to a cardiologist prior to the hip surgery.
A 55-year-old patient on chronic dialysis is scheduled for revision of a left forearm dialysis fistula. The patient receives general anesthesia for the case and has a cardiac arrest mid-surgery. The patient’s family sues, and the plaintiff attorney orders an audit trail. The audit trail shows that the patient’s potassium level prior to surgery was markedly elevated at 8.1, and this lab value was available on the chart 30 minutes prior to the induction of anesthesia, and the anesthesiologist never clicked on the laboratory value to check what the result was prior to the surgery. The plaintiff wins the malpractice lawsuit.
A subpoena for audit trail information must be for legitimate reasons.
There is no clear precedent currently on the issue of whether a defendant health care provider must produce an audit trail as a matter of standard course as if it were the medical record itself. Courts surprisingly are deciding the issue primarily on relevance grounds.
Once the audit trail is produced and counsel has had a chance to review it to the care rendered, plaintiff’s counsel may seek to make an issue regarding the truthfulness of the information contained in the EMR at trial including allegations of alteration or wrongdoing.
Simple conjecture or inferences that an EMR record was altered based on a review of the audit trail is not enough, and expert testimony to support that position may be required. Absent expert testimony, a plaintiff patient was not permitted to present evidence to the jury.
Each time a patient’s EMR is opened, regardless of the reason, the audit trail documents this detail. The audit trail cannot be erased, and all events related to the access of a patient’s EHR are permanently documented in the audit trail. Providers cannot hide anything they do with the medical record. No one can escape the audit trail. It’s easy to see how and why an audit trail could serve as an important piece of evidence in a medical malpractice action.
In printed form, [audit trails] can look like gibberish to the untrained eye. Fortunately, there’s a simple solution to these problems: the use of an expert trained in understanding and navigating EMR systems and interpreting and explaining audit trails.
The take-home message: the era of “buffing the chart” is over. Whenever we healthcare providers click on any item on the EMR, or whenever we don’t click on an item on the EMR, a Big Brother Audit Trail is watching and permanently recording who accessed the EMR, which patient item was accessed, at what time, and what action was performed.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Imagine this scenario: You’ve just finished anesthetizing a patient in a hospital setting, and the patient now requires transport from the operating room (OR) to the post-anesthesia care unit (PACU). During surgery your patient monitors included: a pulse oximeter, an ECG, a blood pressure cuff, a temperature monitor, and a monitor of the oxygen, carbon dioxide, and anesthetic concentration of every breath inhaled and exhaled. During the transport to the PACU, a trip which can be as short as 1 minute or as long as 5 minutes, there are no specific standards regarding monitoring. It’s common for zero monitoring equipment to be attached to the patient. It’s also not uncommon for the patient to be breathing room air during transport. When you arrive at the PACU, a nurse reattaches your patient to the vital sign monitors, and discovers that the patient’s oxygen saturation has dropped from 100% in the OR to a severely low value of 80% in the PACU.
Patients can have inadequate breathing on arrival at the PACU for multiple reasons, including oversedation from narcotics, oversedation from propofol or general anesthetic gases, residual paralysis from muscle paralysis drugs, upper airway obstruction, laryngospasm, obesity, sleep apnea, or pulmonary disease. An anesthesiologist can easily make a diagnosis of inadequate breathing if a patient is connected to a pulse oximeter. Should we routinely monitor a patient’s oxygen saturation level during transport to the PACU? Let’s examine current standards and policies regarding anesthesia patient transport and review the published incidence of inadequate oxygenation following OR to PACU transport.
“A PATIENT TRANSPORTED TO THE PACU SHALL BE ACCOMPANIED BY A MEMBER OF THE ANESTHESIA CARE TEAM WHO IS KNOWLEDGEABLE ABOUT THE PATIENT’S CONDITION. THE PATIENT SHALL BE CONTINUALLY EVALUATED AND TREATED DURING TRANSPORT WITH MONITORING AND SUPPORT APPROPRIATE TO THE PATIENT’S CONDITION.”
This sounds like a reasonable standard, but it’s non-specific and leaves the decision regarding oxygen therapy and monitoring up to the individual member of the anesthesia care team’s judgment.
After an anesthetic, the patient is usually transferred to the PACU or an ICU. This guideline sets out to clarify the type of patients who will need monitoring during transportation, and the nature of monitoring required.
Monitoring during transport is mandatory for the following patients
· Any patient designated as needing ICU care, irrespective of whether the patient actually goes to the PACU or an ICU.
· Patients who are receiving vasopressors, vasodilators, or inotropes.
· Any patient who has a pulmonary artery catheter in situ.
· All intubated patients.
· Any patient who has had an unstable course during the anesthetic.
· Any patient who needs to be transported for longer than 5 minutes to the recovery area.
The above list is not exhaustive and monitoring for transportation may be instituted for any patient at the discretion of the anesthesiologist.
This is a reasonable policy, but what if anesthesia patient transport to the PACU lasts 4 minutes and 59 seconds (i.e. a long transport, but less than 5 minutes to the recovery area)?
The most common complications for in-hospital transported patients are respiratory, meaning that a patient has inadequate breathing and/or inadequate oxygen therapy during transport. The following five studies document that unmonitored patients frequently have low oxygen levels following transport to the recovery room.
In the 2012 study Does the transportation of patients from the operating room to the post-anesthetic care unit require supplemental oxygen? the authors prospectively looked at 50 patients transported from the OR to the PACU. They measured the oxygen saturation when each patient left the OR and when the patient arrived in the PACU. Moderate hypoxemia (oxygen saturation 86% to 90%) and severe hypoxemia (oxygen saturation less than 85%) occurred in 8% and 4% of patients, respectively. Seventy-five percent of the patients with moderate or severe hypoxemia were obese, and 42% were smokers.
959 patients underwent elective surgery under general anesthesia in a university hospital. All were transported to the PACU on room air without oxygen supplementation. The oxygen saturation level was measured at the end of the transfer to the PACU. Seventeen percent of patients had a pulse oximetry reading < 90%, and 6.6% had a pulse oximetry reading < 85%. The authors concluded that “transportation of patients breathing room air from the OR to the PACU directly after GA without use of PO or supplemental oxygen seems to be questionable in terms of patient safety.”
In the 2015 study, Impact of medical training clinical experience on the assessment of oxygenation and hypoxemia after general anesthesia: an observational study, anesthetists, nurses, and medical students estimated the oxygen saturation level in their patients at the end of transfer to the PACU, after the patients had been breathing room air during the transfer following surgery under general anesthesia. The estimated oxygen saturation level was compared to the actual oxygen saturation level measured by pulse oximetry. Low oxygen saturation (oxygen saturation < 90 %) occurred in 154 out of 1,138 patients (13.5 %). Anesthetists, nurses, and medical students accurately identified only 25, 23, and 21 of the 154 patients as being hypoxemic, respectively. The authors concluded that “considering the uncertainty about deleterious effects of transient, short-lasting hypoxemia, routine use of pulse oximetry is advocated for patient transfer to the PACU.”
In the 2016 study Predictors of desaturation during patient transport to the postoperative anesthesia care unit: an observational study, 13% of505 patients had hypoxemia during transfer to the PACU. The three risk factors for low oxygen saturation were a Richmond agitation-sedation (RASS) score lower than -2, an oxygen saturation <96% before exiting the operating room, and a body mass index >30. Seventy-two percent of the patients were transferred without oxygen, and most of the hypoxemia appeared in these patients. The authors concluded that the development of hypoxemia during transfer from the OR to the PACU was greater in patients who were more sedated, obese, or had lower oxygen saturations when they left the OR. The authors also concluded that “supplemental oxygen should be considered in higher risk patients.”
In the 2020 study Complications associated with the anesthesia transport of pediatric patients, the authors looked at a database of 2971 events pediatric adverse events, and 5% (148 events) were related to patient transport. The adverse events were primarily respiratory. Nearly 40% of the reported adverse events occurred in infants of an age less than or equal to 6 months. Seventy-five percent of the adverse respiratory events occurred postoperatively during transport from the OR to the PACU or the OR to the intensive care unit (ICU).
The distance from the OR to the PACU in the hospital I work at can be as much as 120 yards, and require anesthesia patient transport times of up to 5 minutes. The hospital supplies oxygen tanks on every gurney used to transport surgical patients from the OR to the PACU. The anesthesiologist administers nasal or mask oxygen to patients during transport.
Regarding respiratory monitoring during transport, a non-electronic monitor formerly utilized by anesthesiologists during patient transport was to pull a patient’s jaw toward the ceiling, with the palm of our hand of spanning across the patient’s mouth. In this manner we could feel each exhaled breath, documenting that the patient was breathing and ventilating themselves.
Since the arrival of COVID and the high risk of the spread of infection, anesthesiologists are wearing gloves whenever they are managing airways, and sensing a patient’s breathing through the thickness of the glove is ineffective. We need pulse oximetry monitoring.
to document adequate breathing and oxygenation.
Every hospital owns portable vital sign monitors that look something like this:
portable vital sign monitor
These devices show real-time numeric values for the oxygen saturation, heart rate, ECG rhythm, and blood pressure, the same vital signs that are followed in the operating room. The acquisition cost for this monitor is currently $1300 per unit. If a hospital has 12 operating rooms, the total cost of 12 X $1300 = $15,600 is a reasonable investment to avoid patient complications of unstable vital signs during transport.
What about a less expensive alternative? What about the inexpensive battery-powered pulse oximeters that clip over a fingertip are readily available at drug stores or on the internet. This product
$22.80 fingertip battery-powered pulse oximeter
is available on Amazon for $22.80, and has been reviewed by over 200,000 individuals to date. I bought one for my home and use it whenever a family member has respiratory viral symptoms. If a hospital stocked inexpensive oximeters like this one, doctors and nurses could diagnose low oxygen saturation in their patient(s) within seconds. Would these small portable devices begin to disappear or get lost? Perhaps. A possible solution would be to assign a fingertip pulse oximeter to each physician or nurse who has a need for one, and to expect them not to lose their own personal device. Could continuous fingertip pulse oximetry prevent hypoxic events during in-hospital transports? Yes. A prospective study testing this practice would be easy to do. The connection of fingertip monitors to a hospital’s electronic medical record (EMR) would not be practical, but the purpose of the monitor is to keep patients safe. Whether the monitor readings are recorded in a vital sign readout of the EMR is a less important factor.
In conclusion, the post-surgical transport of a patient from the operating room to the PACU is a period of patient risk. The routine use of supplemental oxygen and the routine use of pulse oximetry can help anesthesiologists decrease this risk of inadequate breathing and low oxygen saturation during transport.
CODA: The transport of post-operative patients from the OR to the ICU is a more complex undertaking than transport of patients from the OR to the PACU. The distances between the OR and the ICU are greater than the distance between the OR and the PACU. The ICU may be on a different floor and necessitate an elevator ride. A patient bound for the ICU may be asleep and intubated, which requires the anesthesiologist to ventilate the lungs with an Ambu bag attached to the endotracheal tube during the transfer. The patient may be requiring infusions of vasoactive drugs to maintain blood pressure within safe limits. The anesthesiologist may be supervising the transfusion of blood, platelets, or plasma. Managing all these factors while vigilantly watching the monitor screen while riding in an elevator with a sick patient is a challenging experience. Indeed, the post-surgical transport of a patient from the OR to the ICU requires an anesthesiologist to manage a rolling intensive care unit experience.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Dermatology and anesthesiology are two medical specialties which offer lifestyle balance. Dermatology is consistently one of the most competitive residencies for graduating medical students. In a ranking of the most competitive medical specialties, dermatology ranked second, trailing only plastic surgery. Dermatology was also ranked as the number-one specialty in terms of work-lifestyle balance. Dermatology is a high-paying medical specialty with almost no emergencies, weekend duties, or night call. Dermatologists can take weeks off work without losing their entire practice. Dermatologists perform procedures with their hands, including biopsies or the resection of lesions. Dermatologists have important roles treating common problems such as chronic acne or diagnosing life-threatening melanomas. Dermatology clinic is known for short visits and long lists of patients. If a patient has multiple medical comorbidities such as hypertension, heart problems, obesity, or sleep apnea, these issues are usually unrelated to the dermatology consultation. Hypertension, heart problems, obesity, and sleep apnea are problems for the patient’s internal medicine doctor, not for the dermatologist. A career in anesthesiology seems markedly different than a career in dermatology, because anesthesiologists frequently deal with acutely ill patients, middle of the night emergency surgeries, and complex anesthetics for open heart, brain, or neonatal surgeries. But one large subset of anesthesia work closely mimics the lifestyle of dermatology practice. Before you sign up for a lifetime as a dermatologist, consider the subspecialty of ambulatory anesthesiology.
Ambulatory anesthesiology is defined as the administration of anesthetics for outpatient surgical procedures, which are minor procedures which don’t require hospitalization. Most anesthetics in the United States are for ambulatory surgeries. In 2014 there were 11 million outpatient surgeries, which was 52% of the total number of surgeries. Outpatient surgeries include tonsillectomy, knee arthroscopy, shoulder arthroscopy, breast biopsy, hernia repair, rhinoplasty, hand surgery, foot surgery, nasal septoplasty, colonoscopy, and upper gastrointestinal endoscopy. These procedures are low-risk surgeries which don’t disturb a patient’s physiology in any significant way. Ambulatory surgery patients are prescreened to eliminate those with medical problems such as morbid obesity, severe sleep apnea, or unstable cardiac, respiratory, or neurologic diagnoses. An anesthesiologist practicing 100% in an ambulatory surgery center should have zero emergency anesthetics, zero weekend duty, and zero night call.
The duration of training for an anesthesiologist and a dermatologist is identical. Both specialties require four years of college, four years of medical school, a one-year medical internship, and three years of residency training. For either specialty, if you graduate high school at age 18, you’ll be at least 30 years old when you finish training and are ready to begin your career. A significant amount of deferred gratification is required for both specialties. Your friends who went to work straight out of college will be at least eight years ahead of you in the game of life, and may have already accumulated a mortgage and 1.93 children during the years you’ve been working as a resident physician and memorizing massive quantities of medical knowledge. Anesthesia will never be as safe or predictable as dermatology. Anesthesia residents are required to manage all forms of cases, including open-heart surgeries, neurosurgeries, trauma surgeries, Cesarean sections, and emergent chest or abdominal surgeries. Major complications are rare in outpatient anesthesia, but if one is inducing general anesthesia, then unexpected complications of airway, breathing, or circulation (the ABCs) can occur.
Samuel Shem’s classic medical satire “The House of God,” followed a cadre of burned-out internal medicine residents through their internship year. At the end of the book, the residents reached the conclusion that their best futures were in the NPC—Non-Patient Care—specialties, which numbered six and only six: Rays, Gas, Path, Derm, Eyes, and Psych, that is: radiology, anesthesiology, pathology, dermatology, ophthalmology, and psychiatry. The main character in “The House of God” switched his specialty from internal medicine to psychiatry. In my career I switched from internal medicine to anesthesiology. Anesthesiology is not truly a “Non-Patient Care” specialty. Anesthesiologists very much care for patients every day. A key difference is that anesthesiologists care for each patient for a short and finite time. We don’t have to deal with a patient’s chronic problems over many years, as their internal medicine doctor must do.
An experienced anesthesiologist may eventually land a fulltime job at an ambulatory surgery center (ASC), and at that point he or she may confine his or her career to a stable weekday life of outpatient surgeries, but this ascension to ambulatory-only anesthesiologist is not common. Most career anesthesiologists who practice in ambulatory surgery centers also continue to practice at a hospital. Most general anesthesiologists need to master both inpatient and outpatient surgeries.
Is it possible to jump directly from the completion of an anesthesia residency to a solely ambulatory practice, thus mimicking the lifestyle of dermatology? In the past, I’d say the answer was no. In recent years the lack of an adequate number of anesthesiologists has created a supply-demand situation in which outpatient surgery centers have insufficient numbers of anesthesiology staff. In some geographic markets, outpatient surgery centers may choose to hire young residents right out of training. I direct you to the recent employment ad below, which promises a salary of $385,000 to $4000,000 per year for an ambulatory anesthesiology job with “No nights, weekends, holidays, trauma, hearts, neuro or OB.”
If you’re interested in a quality lifestyle medical career with regular hours, weekends off, and few emergencies, add the option of ambulatory anesthesiologist to your list of possible choices. But to gain entrance to the Emerald City of ambulatory anesthesiology, you’ll have to walk a Yellow Brick Road through a challenging anesthesia residency first. In all probability, you’ll spend your early career doing some inpatient emergency anesthesia as well. But an eventual career in ambulatory anesthesiology is an outstanding option in which you can anesthetize patients on a weekday schedule, spend weekends and evenings with your family, and turn the ringer off on your cell phone when you go to sleep at night.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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(SPOILER ALERT – CONTAINS PLOT REVELATIONS FROM HOUSE OF THE DRAGON, SEASON 1 EPISODE 1) Twenty million people tuned in to watch the first week of HBO’s House of the Dragon (the Game of Thrones prequel). The firstepisode contained a gory scene of an awake Cesarean section. Queen Aemma was in the process of giving birth to a male heir, the baby was presenting feet first (breech), and was stuck,and could not be delivered vaginally. Grand Maester Mellos (a medieval physician-equivalent) offered a potential solution to the king. He said, “During a difficult birth, it sometimes becomes necessary for the father to make an impossible choice. To sacrifice one, or to lose them both. There is a chance that we can save the child. A technique that is taught at the Citadel—which involves cutting directly into the womb to free the infant. We must either act now or leave it with the gods.” Soon after that conversation a knife descended as Mellos cut into the queen’s abdomen while she screamed and the king whispered into her ear that he loved her. The blood loss from the procedure left the queen dead from hemorrhagic shock. On the day following the broadcast, social media erupted at this non-consensual torture waged against the mother.
From a doctor’s perspective, could this fictional scene really have happened centuries ago? It’s a fact that cutting a child out from his mother’s womb was a death sentence for the mother in an era prior to the discovery of anesthesia and prior to the discovery of surgical techniques to control bleeding and infection. In the real history of our world, it’s unlikely any husband or family was offered the choice whether to sacrifice the birthing mother to save the child. Most Cesarean sections were done because the mother was already dead and cutting into the womb was a last gasp measure to save the child’s life. As House of the Dragon depicted, in primitive times there was no way to stop the acute bleeding from Cesarean incisions into the abdomen and the uterus.
The medical advances that enabled nearly all women to survive Cesarean section were: 1) the discovery of sterile surgical practices of handwashing and antisepsis to prevent postoperative infections; 2) the discovery of surgical techniques to stop bleeding; and 3) the discovery of anesthesia.
Sterile surgical procedures began when Dr. Ignaz Semmelweis, a Hungarian physician, noted in 1847 that fewer women died from post-surgery fever if surgeons washed their hands. Years later Dr. Louis Pasteur and Dr. Joseph Lister provided evidence to explain germ theory. Dr. Lister’s principles of antiseptic care led the way to asepsis, which was the complete elimination of bacteria during surgery.
Prior to the discovery of general anesthesia, sedation for surgery usually included oral alcohol drinks, or opiates derived from poppies. General anesthesia was discovered in October 1846, when Dr. William Morton gave a public demonstration of inhaled ether use at the Massachusetts General Hospital in Boston. One year later, James Simpson, a Scottish obstetrician, administered ether to relieve the pain of childbirth for a woman with an abnormal pelvis. In 1853 Dr. John Snow gave Queen Victoria the inhaled anesthetic chloroform to relieve labor pain during the birth of her eighth child.
A modern Cesarean section is most often done under a spinal or epidural anesthetic. The anesthesiologist injects a local anesthetic drug into the mother’s low back to render her numb from the level of her nipples to her toes. Under this regional anesthetic, a mother can be awake to bond with her infant minutes after the child is born. In emergency circumstances, general anesthesia may be required for Cesarean section. In these situations, a general anesthetic drug such as propofol is injected into the mother’s intravenous line, rendering her unconscious within 20-30 seconds. The anesthesiologist then inserts an endotracheal breathing tube into the mother’s windpipe (trachea) to ensure that oxygen and anesthesia gases are delivered directly and safely into the lungs, and at the same time eliminating the risk of stomach contents regurgitating into the mother’s lungs.
Cesarean sections in the United States today are typically controlled surgeries, with comfortable mothers and with the father present in the operating room holding the mother’s hand. Expectant mothers can be reassured that because of advances in anesthesia and surgery, the pain, horror, and lethal outcome from a Cesarean section as depicted in the House of the Dragon will not occur in the modern world of medicine.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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There are hundreds of anesthesia textbooks, but which current books are the gold standards for anesthesia knowledge? Should you buy these books, or should you advocate that your hospital purchase them for the medical library? When I was in residency training, I bought earlier editions of many of these textbooks so I could underline and highlight pertinent pages. If you purchased all 11 books in a print version today it would cost $1,643.49. The twenty-first century is a digital age, and if you purchased all 11 books in an ebook version today it would cost slightly less, at $1453.00. I currently have access to these ebooks through Stanford University’s Lane Medical Library, and I read them remotely through the Lane Library’s online website. I’ve come to prefer to read a digital copy over a hardcover book. A digital copy of a textbook is easy to access, easy to search keywords, and it’s convenient to print out excerpts or chapters. A digital textbook collection is portable, and can travel with you in your laptop, your phone, or your tablet. Digital access to all this written expertise can be at your fingertips anywhere, including in the operating room suite.
The Anesthesia Consultant’s 2022 Listof the Top Anesthesia Booksincludes:
Miller’s Anesthesia, 9th edition, 2019, Editor-in-Chief Michael Gropper. Miller’s has been the comprehensive textbook in our specialty since the first edition in 1981, and it touches on every facet of anesthesiology. All anesthesia providers should have access to the current two-volume 3112-page edition. (ebook $299.99, hardcover $327.16)
Anesthesiologist’s Manual of Surgical Procedures, 6th edition, 2019, Editor-in-Chief Richard Jaffe. This textbook is organized by surgical subspecialties, and contains a catalog of almost every common surgical procedure in a fashion analogous to an academic “cookbook.” Both surgeons and anesthesiologists analyze each procedure, and include the pertinent details of might be described as an “anesthesia recipe” for each type of case. (ebook $165.29, hardcover $126.17)
The Stanford Emergency Manual. This is a free laminated guide with algorithms describing the diagnosis and treatment of the 26 most common ACLS and non-ACLS perioperative anesthesia emergencies. This is an essential cognitive aide for every operating room, code cart, and anesthetizing location in the world. (Free download)
Kaplan’s Cardiac Anesthesia: In Cardiac and Noncardiac Surgery, 7th edition, 2016, Editor Joel Kaplan. For decades Dr. Joel Kaplan has been the go-to author regarding cardiac anesthesia as well as the management of cardiac disease in noncardiac surgery. This textbook combines both topics into a single volume. (ebook $201.99, hardcover $270.49)
A Practical Approach to Regional Anesthesiology and Acute Pain Medicine, 5th edition, 2017, Editors Joseph Neal, De Tran, and Francis Salinas. From its beginning at Seattle’s Virginia Mason Clinic nearly 30 years ago, this textbook remains the top resource in the burgeoning fields of ultrasound-guided regional anesthesia and acute pain medicine. (ebook $106.99, paperback $78.07)
Chestnut’s Obstetrics Anesthesia: Principlesand Practice, 6th edition, 2014, Editor David Chestnut. First published in 1984, this is the leading textbook covering the field of obstetric anesthesiology. (ebook $152.49, hardcover $172.99)
A Practice of Anesthesia for Infants and Children, 6th edition, 2018, Editors Charles Cote and Jerrold Lerman. Cote’s book has been the bible for pediatric anesthesiologists for nearly fifty years. (ebook $146.49, hardcover $203.11)
Stoelting’s Anesthesia and Co-existing Disease, 8th edition, 2021, Editors Roberta Hines and Stephanie Jones. First published in 1983, Stoelting’sAnesthesia and Co-existing Disease is the leading textbook regarding co-existing and uncommon diseases, with a stated goal to “provide a concise description of the pathophysiology of disease states and their medical management that is relevant to the care of the patient in the perioperative period.” (ebook $110.49, hardcover $128.01)
Complications in Anesthesia, 3rd edition, 2017, Editors Lee Fleisher and Stanley Rosenbaum. First published in 1999, this textbook lists 223 chapters, each detailing a specific problem/complication in perioperative medicine, and includes a step-by-step approach to understanding the pathophysiology and the treatment of each complication. (ebook $85.49, hardcover $114.65)
Miller’s Basics of Anesthesia, 8th edition, 2022, Editor Manual Pardo. (ebook $62.99, hardcover $99.99) First published in 1984, this is a condensed version of the two-volume 3112-page Miller’s Anesthesia tome listed as #1 above. In the 1990s my anesthesia chairman stated, “If a trainee knew everything written in this book, they’d be able to pass the American Board of Anesthesiology written and oral exams.” I would agree. The most important topics of anesthesia practice are well-presented in this 960-page book.
Anesthesia Equipment: Principles and Applications, 3rd edition, 2020, Editor Jan Ehrenwerth. Every anesthesia professional should understand the machines they utilize. This textbook, was first published in 1993, answers the questions pertaining to anesthesia machines, airway equipment, monitors and other perioperative devices. (ebook $120.79, hardcover $122.85)
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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JAMA Surgery published the study “Association of Anesthesiologist Staffing Ratio With Surgical Patient Morbidity and Mortality”on July 22, 2022. This was a landmark paper on the topic of anesthesiologist:CRNA staffing ratios, which documented that having physician anesthesiologists direct three or four operating rooms simultaneously for major noncardiac inpatient surgical procedures increased the 30-day risks of patient morbidity and mortality. The senior author was Sachin Kheterpal, MD, MBA, of the Department of Anesthesiology at the University of Michigan Medical School. The data was from a retrospective matched cohort study of major noncardiac inpatient surgical procedures performed from January 1, 2010, to October 31, 2017, and was conducted in 23 academic and private hospitals in the United States.
The University of Michigan paper stated, “this study primarily analyzed physician-CRNA teams, the dominant practice model in US anesthesiology.” The physician-CRNA team, otherwise known as an anesthesia care team, is a model strongly supported by the American Society of Anesthesiologists. The anesthesia care team is a system in which one anesthesiologist covers one, two, three, or four separate operating rooms, each room staffed by a Certified Registered Nurse Anesthetist (CRNA) or an anesthesia assistant (AA). From a very large initial data set of 3,624,399 operations, the University of Michigan authors calculated the staffing ratio of physician anesthesiologist: CRNA for each operation. The following types of cases were excluded: anesthesia care personally performed by a physician anesthesiologist working alone; anesthesia care which involved an anesthesia assistant; anesthesia care involving an anesthesia resident; and anesthesia care that occurred overnight, during weekends, or on holidays. After these exclusions were applied, the data set consisted of 866,453 operations, in which 1960 anesthesiologists provided care in 23 different hospitals.
Data was divided into four groups:
Group 1: one anesthesiologist covering one operation (48,555 patients)
Group 1-2 (reference group): one anesthesiologist covering more than one to no more than two overlapping operations (247,057 patients)
Group 2-3: one anesthesiologist covering more than two to no more than three overlapping operations (216,193 patients)
Group 3-4: one anesthesiologist covering more than three to no more than four overlapping operations (67,010 patients)
The four groups were studied regarding 30-day morbidity and mortality outcome data. The morbidities included cardiac, respiratory, gastrointestinal, urinary, bleeding, and infectious complications. Overall, morbidity and mortality occurred after 30,026 operations (5.19%).
The results:
Compared with patients in group 1-2, those in group 2-3 had a 4% relative increase in mortality and morbidity (5.06% vs 5.25%; P = .02).
Compared with patients in group 1-2, those in group in group 3-4 had a 14% increase in risk-adjusted mortality and morbidity (5.06% vs 5.75%; P < .001).
The paper stated, “When 100,000 operations, which is typical annually for a major medical center, are considered, the increase in risk from 5.06% to 5.75% that we observed would translate to an additional 690 operations with adverse outcomes,” and “increased overlapping anesthesiologist coverage beyond 1 to 2 operations was associated with an increased risk of surgical patient morbidity and 30-day mortality. Because 313 million surgical procedures are performed worldwide each year, any small individual improvements in outcome can have major repercussions for public health. These results complement previous studies that have shown improved 30-day mortality and morbidity rates after complications when anesthesiologists directed anesthesia care.”
The results of this study may be criticized because the data was retrospective, but it’s unlikely any prospective study will ever be done randomizing major noncardiac inpatient surgeries to anesthesiologist:CRNA ratios of 1:1, 1:2, 1:3, and 1:4. The adoption of Electronic Medical Records (EMRs) brought on the arrival of Big Data such as in this paper, in which a Herculean total of over 3.6 million charts were studied. An EMR enables physicians to study trends and outcome data in ways that were previously impossible. Does the data from the University of Michigan study support the fact that decreased staffing by physician anesthesiologists in major noncardiac inpatient surgical procedures is associated with increased 30-day morbidity and mortality? Yes, it does. Will this conclusion change the future practice of anesthesiology? Perhaps, but probably not. Why not? Let’s examine the most likely reasons behind the increased anesthesiologist:CRNA staffing ratios:
There may be an inadequate supply of physician anesthesiologists to staff all major noncardiac inpatient surgical procedures at anesthesiologist:CRNA ratios of 1:1 or 1:2. There were 31,130 anesthesiologists in the United States in 2021, and more than 55,000 CRNAs in the United States. There were approximately 21 million surgeries per year in the United States in 2014. The ratio of the number of surgeries compared to the number of anesthesiologists (21,000,000/31,130) equals 675 surgeries per anesthesiologist, a busy caseload. But the geographical distribution of where anesthesiologists live is not random, with populations of MD anesthesiologists concentrated in urban and suburban areas, and populations of MD anesthesiologists less concentrated in rural areas. Some locations have an inadequate census of physician anesthesiologists to staff every case as solo practitioners or at an anesthesiologist:CRNA ratio of 1:1 or 1:2.
A higher anesthesiologist:CRNA ratio may be a strategy to decrease the cost of anesthesia care. This issue was examined in detail in the American Society of Anesthesiologists Monitor. In this study, the reported average yearly salary for a CRNA was $202,000, and they worked 40 hours per week. The reported average yearly salary for a private practice anesthesiologist was $440,000, and they worked 55 hours per week. Cost-analysis showed that with adequate numbers of CRNAs to staff anesthesia care teams and to cover breaks for working CRNAs, the anesthesiologist:CRNA ratios of 1:2 and 1:3 were actually more expensive than running the rooms with a solo anesthesiologist in each room. An anesthesiologist:CRNA ratio of 1:4 was only marginally (< 10%) less costly than running the rooms with a solo anesthesiologist in each room.
Figure 3: 7 a.m. to 5 p.m. with break staff included. Because one needs 1.25 CRNAs per site to cover the 10-hour shifts, the cost savings for anesthesia care team model is further reduced. Anesthesia care team costs are compared to physician-only (MD-only). Spikes in costs are when the number of sites cannot be divided by the staffing ratio.
Medical direction of four CRNAs –> the anesthesiologist can bill 50% of Physician Allowed Amount and 50% of CRNA Allowed Amount.
With four operating rooms directed by one anesthesiologist, the 1st, 2nd, 3rd, and 4th operating rooms can each be billed at 50% of the anesthesia fee. Billing for four rooms simultaneously can increase the income for that solitary anesthesiologist over that time period. An anesthesiologist working alone, without CRNAs, can only attend to one patient, and can only bill services for a single patient. An analogy is a taxicab or Uber driver who can only bill for one ride at a time. The only way for a solo taxi driver or Uber driver to earn more money is to give more rides, and the only way for a solo anesthesiologist to earn more money is to do more cases for more hours of time.
The senior author of the University of Michigan study was Sachin Kheterpal, MD, MBA from the Department of Anesthesiology, yet the study was published in a surgical journal, JAMA Surgery, rather than an anesthesiology journal.Did anesthesiology journals reject the opportunity to publish the study? I don’t know. It’s pertinent that surgeons care greatly about the outcomes of surgeries they perform, and surgeons are less concerned with the economics of anesthesia staffing. Surgeons reading this study will no doubt conclude that an anesthesia group covering major noncardiac inpatient surgical cases with 1:3 or 1:4 anesthesiologist:CRNA staffing ratios are exposing their patients to an increased risk of morbidity and mortality.
Will this study change the anesthesiologist:CRNA staffing ratios in the future? My gut impression is that it will not. Anesthesiologists do not routinely read JAMA Surgery and may be quick to dismiss the findings. Surgeons may complain to their anesthesia colleagues that they do not want 1:3 or 1:4 anesthesiologist:CRNA staffing ratios for their major noncardiac inpatient surgical patients, but it’s unlikely they will have any power to enact change if the anesthesiologists don’t want to change. Why would anesthesiologists not move away from 1:3 or 1:4 anesthesiologist:CRNA staffing ratios? See the three reasons above: an inadequate supply of physician anesthesiologists; the quest to decrease anesthesia costs; and the goal of maximizing anesthesiologist income by directing 3 or 4 operating rooms at the same time.
I asked the anesthesia chairman of a large health-maintenance organization (HMO) how his group assigned anesthesia staffing, and his reply was that they used tiered staffing. A demanding case such as an open-heart surgery or a craniotomy was staffed by a solo physician anesthesiologist. In contrast, simple low-risk cases such as bunion repairs or carpal tunnel repairs on healthy patients were staffed by the maximal anesthesiologist:CRNA ratio of 1:4. The spectrum of remaining cases fell between these two extremes, and the anesthesiologist:CRNA ratio was assigned according to the difficulty and the risk of the anesthetic.
As a patient, how do you feel about all this? Would you be concerned if you were to be anesthetized by an anesthesia care team utilizing a 1:3 or 1:4 anesthesiologist:CRNA staffing ratio? In the University of Michigan study, if your surgery was a major noncardiac inpatient surgery during daytime hours, the data showed that your anesthesia team is putting you at increased risk for 30-day morbidity and mortality. The University of Michigan study only examined inpatient surgeries, so if you’re having outpatient ambulatory surgery, this study does not apply to your surgery. In 2014, outpatient surgery outnumbered inpatient surgery by 11,474,800 to 10,303,000. But if you or your family member are scheduled for major noncardiac inpatient surgery, it’s important to ask the question of what the anesthesiologist:CRNA staffing ratio will be while you or your family member are asleep, and how much of the time will your anesthesiologist be in the operating room.
If I was to be cared for by an anesthesiologist:CRNA ratio of 1:3 or 1:4 for a major noncardiac inpatient surgery during daytime hours, I would raise an objection before the anesthetic started, and I would direct my objection at both the attending anesthesiologist and the attending surgeon. Based on the data from the University of Michigan study, I would request an anesthesiologist:CRNA ratio of no higher than 1:2, or I would request a solo anesthesiologist to attend to me.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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How do anesthesiologists monitor the degree to which a patient’s muscles are pharmaceutically paralyzed during an anesthetic? A recent publication in our specialty’s most prestigious journal urges the use of a QUANTITATIVE neuromuscular monitoring machine to do this when general anesthetics include a paralytic drug. The article was not a prospective randomized study, but rather a retrospective (from 2016 to 2020) practice initiative from a solitary medical center. The goal of the authors (Weigel et al) was to measure the reversal of neuromuscular paralysis in all anesthetized patients at the end of their anesthetic, and to document that reversal in the patient’s chart.
Their measured goal was to document a train-of-four ratio of greater than or equal to 0.9 prior to extubation in each anesthetized patient. What is a train-of-four? A locomotive with four cars? Alas no. A train-of-four ratio is a monitor of the level of neuromuscular blockade. Four consecutive electronic stimuli are delivered along the path of a patient’s nerve. The twitch response of the muscle is measured in order to evaluate stimuli that are blocked, versus those that are delivered. Four consecutive muscle contractions of equal strength (a score = 1.0) occur if there is no neuromuscular blockade. If neuromuscular blockade is present, there will be a loss of twitch height of the final twitch compared to the first twitch, and the resulting ratio of the final twitch height/first twitch height (e.g. 4/5 = 0.8) will indicate the degree of blockade. The clinical concern is that a ratio of lower than 0.9 correlates with a weak patient who may not safely ventilate himself/herself.
The conclusion of the Weigel study boldly states, “Anesthesia providers are solely responsible for properly rescuing patients from the states of paralyses they initiate. This should occur for ALL PATIENTS as verified by QUANTITATIVE measurement and documentation of train-of-four ratios greater than or equal to 0.9.” (Capital letters added by me.)
Should the American Society of Anesthesiologists (ASA) add QUANTITATIVE neuromuscular monitoring as a standard of care?
Hmm. This would be a marked change because, to my observation, almost no anesthesia providers routinely use QUANTITATIVE neuromuscular monitoring at this time.
The article states, “The dangers of paralyzing a patient with neuromuscular blocking drugs are well recognized. Despite advances in anesthetic management, approximately half of all patients arriving to the postanesthesia care unit (PACU) suffer from residual blockade defined as a train-of-four ratio less than 0.9.” They cite a previous article from Anesthesia and Analgesia in 2018 which stated: “whenever a neuromuscular blocker is administered, neuromuscular function must be monitored by observing the evoked muscular response to peripheral nerve stimulation. Ideally, this should be done at the hand muscles (not the facial muscles) with a quantitative (objective) monitor. Objective monitoring (documentation of train-of-four ratio ≥0.90) is the only method of assuring that satisfactory recovery of neuromuscular function has taken place.(Bold emphasis added by me.) The panel also recommends that subjective evaluation of the responses to train-of-four stimulation (when using a peripheral nerve stimulator) or clinical tests of recovery from neuromuscular block (such as the 5-second head lift) should be abandoned in favor of objective monitoring.”
The American Society of Anesthesiologists (ASA) sets the standard of care for intraoperative monitoring. The ASA Standard of Anesthesia Monitoring currently does not mandate any form of neuromuscular monitoring. The ASA Standard of Anesthesia Monitoring is the gold standard for all operating room monitoring, is followed by all training programs, and is referred to in courts of law as the standard of care should an adverse anesthesia outcome occur.
I suggest three values in anesthetic care: Do the right thing, be safe, and Keep It Simple Stupid (the KISS principle). Rather than strapping a thumb monitor onto every one of my patients, I’m a disciple of qualitative neuromuscular monitoring—a less technologically complex form of monitoring. When I was serving my residency training in anesthesiology at Stanford in the 1980s, each resident was equipped with a MiniStim nerve stimulator, which is a qualitative neuromuscular monitor.
MiniStim qualitative neuromuscular monitor
A qualitative neuromuscular monitoring device is simple to use. When the two terminals are applied to the facial nerve lateral to the eye of a sleeping patient and the green button is pushed, the orbital muscles will twitch if unparalyzed, and they will not twitch if paralyzed. With experience one can easily discern whether the patient is paralyzed or not, and one can estimate the degree of paralysis. The MiniStim also has a tetanus feature. When the two terminals are applied to the facial nerve lateral to the eye of a sleeping patient and the red button is pushed, a sustained electrical energy is emitted between the two terminals. The orbital muscles will show a sustained contraction if unparalyzed, and will not contract at all if fully paralyzed. If partially paralyzed, the muscles will contract and then the contraction will fade away in seconds. With experience, one can estimate to what degree the patient is paralyzed. The qualitative neuromuscular monitor does not give you the exact data, i.e. a decimal number between 0.0 (totally paralyzed and 1.0 (no paralysis) that a QUANTITATIVE neuromuscular monitor does.
I still carry a MiniStim, and have used one for the entire 38 years I’ve practiced anesthesia, and for the 30,000 patients I’ve anesthetized. I would not start a case without a neuromuscular qualitative monitor. I would not want to be a patient receiving a neuromuscular paralytic drug if the anesthesiologist did not utilize a neuromuscular monitoring device similar to the MiniStim. The MiniStim is no longer manufactured, but other similar qualitative neuromuscular monitors are easily purchased, e.g. as depicted below, for $251, with no additional disposable costs.
Prior to 2015, the only reversal agent for pharmaceutical paralysis with a non-depolarizing neuromuscular blocker such as rocuronium was the drug neostigmine. Neostigmine can cause the side effect of severe bradycardia (slowing of the heart rate), and had to be administered intravenously in combination with glycopyrrolate (Robinul) or atropine. If a surgery was concluding and the patient had residual neuromuscular paralysis, the anesthesia provider needed to administer the combination of neostigmine/Robinul well before the wakeup-time, because the peak effect of neostigmine occurs at 10 minutes after administration. If the patient was markedly paralyzed, e.g. the qualitative neuromuscular monitor showed no significant twitch or tetanus activity, neostigmine could not adequately reverse the neuromuscular paralysis in a short time. Sometimes it took 20-30 minutes before a deep neuromuscular paralysis could be reversed with neostigmine. If an anesthesia provider erroneously chose to awaken a patient prior to the time their neuromuscular paralysis was reversed or worn off, the patient would be too weak to breathe normally. A medical complication of hypoventilation or of awake paralysis could occur.
Because of sugammadex, the risk of untreated residual neuromuscular paralysis has never been lower. Unreversed neuromuscular paralysis at wake-up should be a never-event now that sugammadex exists. There is virtually no circumstance in which an attending anesthesia provider should have unreversed neuromuscular paralysis at the present time. Why, in 2022, should we advocate for a QUANTITATIVE neuromuscular monitor which is bulky, expensive, and can only be strapped onto the thumb? The thumb location is a disadvantage, because many anesthetics, for example laparoscopies, require the arms to be tucked at a patient’s sides during surgery, and a thumb monitor is not practical. The qualitative neuromuscular monitors work on any peripheral nerve: e.g. the ulnar nerve at the wrist, the facial nerve lateral to the eye, or the posterior tibial nerve in the ankle, and provide a more versatile monitor than the QUANTITATIVE neuromuscular thumb monitor.
Qualitative neuromuscular monitoring is useful, easy, versatile, and inexpensive. QUANTITATIVE neuromuscular monitoring has the appeal of a score—a number between 0 and 1.0—that can be added to the already burdensome printout of the Electronic Medical Record (EMR), and may seem satisfying to those addicted to the dubious wonders of the EMR, or to those who want to see QUANTITATIVE neuromuscular monitors reported in the medical literature. But the addition of QUANTITATIVE neuromuscular monitoring to the required ASA list of monitors at this time is premature.
Where is the science? Where is the prospective, randomized trial of QUANTITATIVE neuromuscular monitoring versus qualitative neuromuscular monitoring in the age of sugammadex? Does anyone really believe that qualitative neuromuscular monitoring will be inaccurate and lead to significant anesthetic complications in an era when sugammadex is available?
Until prospective scientific evidence demonstrates that QUANTITATIVE neuromuscular monitoring improves outcomes, mandating the extra technology of QUANTITATIVE neuromuscular monitoring as a required standard is not the correct path for the ASA to take in 2022 or at any time in the future.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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What’s the difference between a physician anesthesiologist and a nurse anesthetist? After the first 3 – 4 years in the workforce, either one can master the manual skills of anesthesia. That is, either one can display excellence in intubating the trachea, performing a spinal or an epidural anesthetic, performing a nerve block, inserting an arterial line, or inserting a central venous pressure catheter. There is no fork in the career path that makes a busy Certified Registered Nurse Anesthetist (CRNA) automatically inferior to a medical doctor anesthesiologist in hands-on skills. So what really is the difference between a physician anesthesiologist and a nurse anesthetist? The answer: internal medicine.
All physician anesthesiologists graduate from medical school, where they rotate through clerkships in surgery, pediatrics, obstetrics-gynecology, internal medicine, emergency medicine and psychiatry, as well as electives in surgical or medicine subspecialties of their choice.
The difference between a physician anesthesiologist and a nurse anesthetist is that the former has a depth of knowledge of 1) the physiology of the human body, 2) the pathophysiology of diseases, 3) the breadth of pharmacology, and 4) the ability to make diagnoses and prescribe treatment. In short, the physician anesthesiologist has extensive training in the internal medicine essentials of 1), 2), 3), and 4) above.
Nurse anesthetists are valuable and integral cogs in American healthcare. It’s not my intention to demean or minimize the role of CRNAs. My goal is to point out the most specific difference between a physician anesthesiologist and a nurse anesthetist.
At Stanford our department is named the Department of Anesthesiology, Perioperative and Pain Medicine. What is Perioperative Medicine? Perioperative Medicine is all the medical care before, during, and after surgery. Is Perioperative Medicine a subspecialty of internal medicine? In a way, it is. Following an internal medicine residency, graduates may subspecialize in cardiology, oncology, pulmonary medicine, kidney medicine, infectious disease, critical care, or . . . perioperative medicine. When I finished my Stanford internal medicine residency, the top four choices among my colleagues for the next step were: #1 a cardiology fellowship, #2 general internal medicine private practice, #3 an anesthesia residency, or #4 an oncology fellowship.
Stanford University now offers a combined internal medicine/anesthesiology residency, with the goal of training leaders in anesthesiology. The PGY1 year is spent entirely on medicine rotations. The PGY2 year consists of all anesthesia rotations. During PGY3-5 years, the resident alternates between 3 months of medicine rotations and 3 months of anesthesia rotations.
The outgoing Chairman of Anesthesiology, Perioperative and Pain Medicine at Stanford is Ronald Pearl MD PhD, an outstanding clinician and scientist who led our department for twenty-two years. In addition to board-certification in internal medicine and anesthesiology, Dr. Pearl is also board certified in critical care medicine. Dr. Pearl is one of the smartest clinicians I’ve ever met. His extensive internal medicine knowledge raises him above other anesthesia providers.
two one-month rotations in: obstetric anesthesiology, pediatric anesthesiology, neuro anesthesiology, and cardiothoracic anesthesiology
a minimum of one month in the adult intensive care unit during each of the three years
three months of pain medicine, including one month in acute perioperative pain, one month in chronic pain, and one month of regional analgesia/peripheral nerve blocks
one-half month in a preoperative evaluation clinic
one-half month in a post anesthesia care unit, and one-half month in out-of-OR locations.
These rotations of an anesthesia resident develop the young doctor into a clinician comfortable in preoperative assessment and management, in the intraoperative administration of anesthesia, and in the postoperative evaluation and treatment of patients.
Currently, internal medicine residency programs are three years in duration, including a one-year internship in internal medicine. During those three years (PGY1 -PGY3) a resident rotates through:
a minimum of 4 months of critical care (medical ICU or cardiac care unit) rotations
a minimum of 1/3 of Internal Medicine training occurs in an ambulatory setting
a minimum of 1/3 of Internal Medicine training occurs in an inpatient setting
a longitudinal continuity clinic of 130 one-half-day sessions over the course of training, including one clinic per month. The continuity clinic includes evaluation of performance data for resident’s panel of patients.
exposure to each of the internal medicine subspecialties and to neurology
an assignment in geriatric medicine
an emergency medicine experience of four weeks
electives available in psychiatry, allergy/immunology, dermatology, medical ophthalmology, office gynecology, otorhinolaryngology, non-operative orthopedics, palliative medicine, sleep medicine, and rehabilitation medicine
These rotations of an internal medicine resident develop the young doctor into a broadly trained clinician experienced in multiple areas.
I’m not advocating that anesthesia departments be folded under the umbrella of their institution’s department of internal medicine. Instead, what I am recognizing is that the field of anesthesiology is more than putting in breathing tubes, arterial catheters, IV lines, or nerve block needles in a variety of different surgical settings. The field of anesthesiology is understanding and managing medical problems before, during, and after surgery, i.e., Perioperative Medicine. Describing our specialty with the word “Anesthesia” is an oversimplification of what we do. If our specialty was newly named today, it would be called Perioperative Medicine, period.
What about pediatric perioperative medicine? Doesn’t pediatric perioperative medicine involve the knowledge base of pediatricians, instead of the knowledge base of internal medicine? Yes. Deep knowledge of pediatric medicine instead of internal medicine (on adult patients) applies to pediatric perioperative medicine. No doubt a pediatrician who then completes an anesthesia residency will likely be an outstanding pediatric perioperative doctor, but only 5.4 % of anesthesia care in the United States is on pediatric patients less than 15 years old. The majority of the knowledge base for anesthesia care pertains to adult patients, i.e. the knowledge base for internal medicine physicians.
Several examples will illustrate why internal medicine forms the backbone of perioperative anesthesia practice. Before surgery, a patient who presents with insulin dependent diabetes, hypertension, hyperlipidemia, and obstructive sleep apnea is an example of the kind of patient an internal medicine doctor sees regularly in his or her outpatient clinic. During surgery, a patient who develops atrial fibrillation or marked hypertension is an example of the kind of events an internal medicine doctor sees in an intensive care unit. After surgery, a patient who presents with chest pain or shortness of breath is an example of the kind of patient an internal medicine doctor sees in the emergency room or in the intensive care unit. Wait . . . you can argue that a CRNA has previous experience working as a registered nurse in an ICU or an emergency room before beginning nurse anesthetist training. But a registered nurse in an ICU or an emergency room does not independently diagnose and treat medical conditions. A registered nurse in an ICU or an emergency room follows written orders from a medical doctor. There is a world of difference between a medical doctor commanding diagnosis and treatment in an ICU/emergency room versus a registered nurse who follows orders.
Should all anesthesia residency training follow the Stanford optional model of combining internal medicine and anesthesia residencies into one program? No. Prolonging the training of every physician anesthesiologist in the United States makes little sense, but those who desire to be leaders will consider this double-residency option.
Recent years brought an attempt to rename the territory of anesthesiologists as the “Perioperative Surgical Home.” The Perioperative Surgical Home is defined as “a patient-centered, team-based, and coordinated perioperative care setup, composed of the head anesthesiologist-perioperativist in tandem with dedicated nurse practitioners and other PSH team doctors.” This is a move in a positive direction, with the intent of better patient care coordinated by an anesthesiologist-led team. There is an economic barrier to the Perioperative Surgical Home, in that the PSH may appear to be a coup attempt for anesthesia departments to take over jurisdictions from preoperative and postoperative internal medicine doctors. Any adoption of the PSH will likely be gradual, as the battle for patients plays out in each medical center.
Instead, a first step is that anesthesia departments redefine themselves as Departments of Perioperative Medicine, and that the academic training for these departments involve increasing time spent expanding the internal medicine knowledge base of residents in medical intensive care units, cardiac intensive care units, medicine wards, and medicine clinics. Performing month after month of repetitive intraoperative anesthesia care has a decreasing return on expanding a resident’s fund of knowledge, and can serve to make the role of a physician anesthesiologists and the role of a nurse anesthetist close to being the same.
It’s important that physician anesthesiologists create perceivable differences between themselves and CRNAs. The role of Perioperative Medical Doctors is a more broad and more specific identity when compared to what nurse anesthetists do. Let’s make our young physician anesthesiologist trainees into Perioperative Medicine Specialists, instead of confusing them with other anesthesia professionals who can also administer propofol, sevoflurane, and rocuronium.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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The first public demonstration of anesthesia, at the Ether Dome in Massachusetts General Hospital
Important advances in the history of anesthesia changed medicine forever. Humans have inhabited the Earth for 200,000 years, yet the discovery of surgical anesthesia was a relatively recent development in the mid-1800s. For thousands of years most surgical procedures were accompanied by severe pain, and the only strategies available to decrease pain were to give patients alcohol or opium until they were stuporous. How did our specialty advance from prescribing patients two shots of whiskey to administering safe modern anesthesia? In chronologic order, my choices for the most important doctors in the history of anesthesia are:
1842. Dr. Crawford Long, Georgia, USA. THE CO-DISCOVERER OF ETHER AS A GENERAL ANESTHETIC. Dr. Long was an American surgeon recognized for introducing the use of inhaled ether as a general anesthetic. Dr. Long administered ether for the first time on March 30, 1842, to remove a tumor from the neck of patient James Venable. Dr. Long dripped ether on a towel through which Mr. Venable inhaled. Dr. Long performed multiple surgeries using this technique, but did not publish his findings until seven years later in 1849 in The Southern Medical and Surgical Journal. As a result, there is a dispute whether Dr. Crawford Long or Dr. William Morton (below) discovered ether anesthesia first.
1846. Dr. William Morton, Boston, USA. THE FIRST PUBLIC DEMONSTRATION OF ETHER AS A GENERAL ANESTHETIC. Dr. Morton performed the first public demonstration of general anesthesia at Harvard’s Massachusetts General Hospital on October 16, 1846. Morton, a local dentist, utilized inhaled ether to anesthetize patient Gilbert Abbott for removal of a tumor on the patient’s neck. According to surgeon John Collins Warren’s account of the operation, “(the patient) said that he had felt as if his neck had been scratched; but subsequently, when inquired of by me, his statement was, that he did not experience pain at the time, although aware that the operation was proceeding.” Morton was unaware of Dr. Crawford Long’s prior work which began four years earlier in 1842. Morton published his accomplishment in the December 1846 issue of Medical Examiner. Comment: Both Dr. Long and Morton deserve recognition for the discovery and eventual application of ether as a general anesthetic drug. The invention of ether changed medical care forever, making painless surgery a reality.
1899. Dr. August Karl Gustav Bier, Germany. THE FIRST TO PERFORM SPINAL ANESTHESIA, AND ALSO THE INVENTOR OF THE BIER BLOCK (AN INTRAVENOUS REGIONAL ANESTHESIA TECHNIQUE FOR HAND OR FOOT SURGERY). Dr. Bier was a German surgeon before the concept of an anesthesia specialist was invented. He performed the first surgery under spinal anesthesia in 1899. Dr. Bier injected cocaine through a spinal needle, which paralyzed the lower half of his patient. Dr. Bier was able to perform painless ankle surgery. The patient was fully conscious during the operation. Comment: Dr. Bier was the father of regional anesthesia, an important tool in the repertoire of a modern anesthesiologist.
Dr. Nikolai Korotkov
1905. Dr. Nikolai Korotkov, Russia. THE DISCOVERY OF THE MEASUREMENT OF BLOOD PRESSURE BY BLOOD PRESSURE CUFF. Dr. Korotkov described the sounds produced during auscultation with a stethoscope over a distal portion of an artery as a blood pressure cuff was deflated. These Korotkoff sounds resulted in an accurate determination of systolic and diastolic blood pressure. Comment: Anesthesiologists monitor patients repeatedly during every surgery. A patient’s vital signs are the heart rate, respiratory rate, blood pressure, oxygen saturation, and temperature. It would be impossible to administer safe anesthesia without blood pressure measurement. Low blood pressures may be evidence of anesthetic overdose, excessive bleeding, or heart dysfunction. High blood pressures may be evidence of inadequate anesthetic depth or uncontrolled hypertension.
The cuffed endotracheal tube
Dr. Aurthur Guedel
1932. Dr. Arthur Guedel, Wisconsin, USA. DEVELOPMENT OF THE CUFFED ENDOTRACHEAL BREATHING TUBE. Dr. Guedel added an inflatable cuff to the distal end of a breathing tube to be inserted into a patient’s trachea. This advance allowed the use of positive-pressure ventilation into a patient’s lungs. Comment: Surgery within the abdomen and chest would be impossible without controlling the airway and breathing with a tube in the trachea. Advanced cardiac life support (ACLS) of Airway-Breathing-Circulation depends on the insertion of a cuffed endotracheal tube.
1934. Dr. John Lundy, Mayo Clinic, Minnesota, USA. THE INTRODUCTION OF INTRAVENOUS THIOPENTAL AND INJECTABLE BARBITURATES. Dr. Lundy of the Mayo Clinic in Rochester, Minnesota introduced the intravenous anesthetic sodium thiopental into medical practice. In 1934, Dr. Ernest Volwiler and Dr. Donnalee Tabern synthesized Pentothal, the first intravenous general anesthetic. Pentothal was first used in humans on 8 March 1934 by Dr. Ralph Waters. Three months later, Dr. John Lundy started clinical trials of thiopental at the Mayo Clinic at the request of Abbott Laboratories. Injecting Pentothal provided a more pleasant induction of anesthesia than inhaling pungent ether. Comment: This was a huge breakthrough. Almost every modern anesthetic begins with the intravenous injection of an anesthetic drug. (Propofol has now replaced Pentothal.)
1941, Dr. Robert Miller, Texas, USA. INVENTION OF THE MILLER INTUBATING LARYNGOSCOPE BLADE. The Miller straight laryngoscope blade was used to elevate the epiglottis and enabled anesthesiologists to directly view the vocal cords and the laryngeal opening in an anesthetized patient, so they could directly place an endotracheal breathing tube into the trachea. Comment: The Miller straight laryngoscope blade is the second most common blade used for direct laryngoscopy today, and my personal favorite.
1943, Dr. Robert Macintosh, England. INVENTION OF THE MACINTOSH INTUBATING LARYNGOSCOPE BLADE. The Macintosh curved laryngoscope blade enabled anesthesiologists to indirectly elevate the epiglottis and view the vocal cords and the laryngeal opening in an anesthetized patient, so they could directly place an endotracheal breathing tube into the trachea. Comment: The Macintosh curved laryngoscope blade is the most common blade used for direct laryngoscopy today.
ventilating the lungs by bag-ventilation via a tracheostomy
1953. Dr. Bjorn Ibsen, Denmark. THE DEVELOPMENT OF THE FIRST INTENSIVE CARE UNIT (ICU). The origin of the ICU followed the Copenhagen polio epidemic of 1952, which caused respiratory failure in hundreds of patients. Hundreds of patients required ventilation for weeks. Dr. Ibsen organized over a thousand medical students who positive-pressure-ventilated the lungs of these patients by bag-ventilation via tracheostomies. This gathering uniting of physicians and medical students to manage sick patients led to Ibsen being considered the “father of intensive care.” Comment: In the ICU, the Airway-Breathing-Circulation management perfected in the operating room was extended to critically ill patients who were not undergoing surgery.
1956. Dr. Charles Suckling. THE DISCOVERY OF HALOTHANE, THE FIRST MODERN INHALED ANESTHETIC. British chemist Charles Suckling synthesized the inhaled anesthetic halothane. Halothane had significant advantages over ether or cyclopropane. Halothane had a more pleasant odor, a higher potency, faster onset, and was nonflammable. Halothane gradually replaced older anesthetic vapors and achieved worldwide acceptance. Comment: Halothane was the forerunner of our modern inhaled anesthetics isoflurane, desflurane, and sevoflurane. These drugs have faster onset and offset times, cause less nausea, and are not explosive like ether was. The discovery of halothane changed inhalation anesthesia forever.
Dr. John Severinghaus and the first blood gas analyzer
1957. Dr. John Severinghaus, UCSF, California, USA. THE FIRST MEASUREMENT OF ACID/BASE CHEMISTRY OF HUMAN BLOOD. Dr. Severinghaus developed the first blood gas analyzer, now on display in the Smithsonian Museum, which measured the pH, pCO2, and pO2 in a sample of arterial blood. https://www.mlo-online.com/continuing-education/article/13008466/blood-gas-testing-a-brief-history-and-new-regulatory-developments He also developed the initial methods for measuring end-tidal gas concentrations in anesthetized patients in the mid-1970s, and he worked with Dr. Eger (below) on the discovery of minimum alveolar concentration of inhaled anesthetics. He died in 2021 at the age of 99 years. Comment: Measuring blood gases in an acutely ill patient is a cornerstone of all ER and ICU medicine. Measuring blood gases is also routine in cardiac, neurosurgical, and trauma anesthesia, and the measurement of end-tidal gas concentration is a standard in general anesthetics today.
1960s. Dr. Ted Eger, UCSF, California, USA. DISCOVERY OF THE MINIMUM ALVEOLAR CONCENTRATION OF POTENT INHALED ANESTHETICS. Dr. Eger defined the science of inhaled anesthesia uptake and concentration when he characterized the Minimum Alveolar Concentration (MAC) of every gaseous anesthesia drug. Per Dr. Eger’s New York Times obituary when he died at the age of 86 in 2017, he was “a leader in the development of a now universally used technique to determine the proper dose of anesthetic gas administered in operating rooms.” Comment: Almost every general anesthetic today includes some form of an inhaled anesthetic such as sevoflurane, desflurane, or nitrous oxide. Dr. Eger’s work defined the principles of how much gas to administer to each patient.
A pulse oximeter probe
Dr. William New
1983. Dr. William New, Stanford University, California, USA. THE DEVELOPMENT OF PULSE OXIMETRY MONITORING. The Nellcor pulse oximeter, co-developed by Stanford anesthesiologist Dr. William New, was the first commercially available device to measure the oxygen saturation in a patient’s bloodstream. The Nellcor pulse oximeter had the unique feature of lowering the audible pitch of the pulse tone as the oxygen saturation dropped, giving anesthesiologists an audible early warning that their patient’s heart and brain were in danger of low oxygen levels. Comment: The Nellcor changed patient monitoring forever. Oxygen saturation is now monitored before, during, and after every surgery. Prior to Nellcor monitoring, the first sign of low oxygen levels was often a cardiac arrest. Following the invention of the Nellcor, oxygen saturation became the fifth vital sign, along with pulse rate, respiratory rate, blood pressure, and temperature.
1987. Dr. Archie Brain, England. DEVELOPMENT OF THE FIRST COMMERCIAL LARYNGEAL MASK AIRWAY. The Laryngeal Mask Airway (LMA) replaced the endotracheal tube as the airway device for many general anesthetics. The LMA can be inserted blindly into a patient’s mouth, does not require the patient to be paralyzed for insertion, is an easy method for securing the airway, and does not require a laryngoscope. The LMA was introduced to the United States market in 1992. Comment: The LMA revolutionized the general anesthetic technique for most extremity surgeries, some head and neck surgeries, and is used as a rescue technique in the American Society of Anesthesiologists Difficult Airway Algorithm (see below).
1990s. Dr. Jonathan Benumof, UCSD, San Diego, California, USA. DEVELOPMENT OF THE DIFFICULT AIRWAY ALGORITHM. Dr. Benumof was the main originator of the American Society of Anesthesiologists Difficulty Airway Algorithm, first published in 1996. The Difficult Airway Algorithm describes pathways to safe airway management, and its application has saved countless lives. Comment: The Difficult Airway Algorithm is the standard of care for managing patients who are difficult to intubate and/or oxygenate. All anesthesiology providers commit the algorithm to memory, because when airway disasters occur there is simply no time for them to Google the correct order of rescue procedures.
These are the top 20 doctors who made major advances in the history of anesthesia as I see them. Who will be the next successful inventor to advance our specialty? At Stanford University our department is titled the Department of Anesthesiology, Perioperative and Pain Medicine. A key question for the future of Anesthesiology is “How do anesthetics work on the brain?” A key question for the future of Pain Medicine is “How can we more effectively block pain?” In 2016 an estimated 20.4% of the adults in the United States had chronic pain, and the relief of pain remains a key unsolved problem. Anesthesiologists or scientists who develop answers to these questions will likely join The Top Doctors in the History of Anesthesia list.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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On May 2, 2022, residents and fellows (medical doctors in their first years of educational work after medical school) at Stanford University Health Care voted to unionize. In an email to medical staff, the Graduate Medical Education administration wrote: “Stanford Health Care (SHC) residents and fellows voted in favor of having The Committee of Interns and Residents (CIR), a local of Service Employees International Union (SEIU), serve as their collective bargaining representative.The votes cast in the election represent the sentiment of 1,049 residents and fellows who participated, out of the 1,478 employed by SHC. Ultimately, 835 voted ‘yes’ to unionization; 214 voted ‘no.’ . . . While we believe that the best relationship with our employees is a direct one without a union, we respect the results. . . . When the results are certified in the coming days, the first stages of the collective bargaining process will begin. . . . We will negotiate with the union in good faith to reach an agreement that reflects your priorities, while maintaining the best parts about training at Stanford.”
Stanford residents and fellows are not alone in choosing to unionize. A total of 1450 residents and fellows at UCSF (University of California San Francisco) recently voted to join the same Committee of Interns and Residents (CIR) union. The UCSF residents stated, “By joining CIR, UCSF residents will be able to negotiate their contracts for the first time, including bargaining for better salaries, benefits, time off, and other provisions that will improve resident life and well-being.”
A total of over 20,000 residents and fellows at hospitals around the U.S. have voted to join this CIR union. What will this development mean to healthcare in the United States? I respect residents and fellows at the highest level. I spent five years as a medical resident, and I can empathize with the demands of their workload. From my current perspective as an attending physician at an academic medical center, how will this unionizing of housestaff (MDs who are residents and fellows) play out?
First off, why form a union? The main reasons are a lack of bargaining power regarding:
Burnout and staffing. Housestaff work up to 80 hours per week, a number that is twice the 40-hour workweek considered standard in the United States, and they do this for a duration of 3 to 7 years, depending on their specialty. The rate of burnout is known to be high in medical doctors, and despite nods to wellness programs at most university hospitals, improvements have been slow in coming. An online survey of doctors finds an overall physician burnout rate of 42%, and the highest percentage of burnout occurred in these six specialties: urology: 54%, neurology: 50%, nephrology: 49%, diabetes and endocrinology: 46%, family medicine: 46%, and radiology: 46%.
COVID. The long hours and risks of acquiring COVID while working with sick COVID patients from 2020 -2022 made many residents and fellows feel vulnerable and angry. While hospital administrators and many faculty returned to the safe havens of their homes each night, interns and residents staffed intensive care units, wards, and emergency rooms, caring for patients with this terrifying new contagious disease. When University of Massachusetts interns and residents joined the CIR union, they stated, “When the pandemic struck, securing better conditions became even more urgent, as the inequities in our healthcare system were laid bare — and in light of the rapid changes that left residents scrambling to keep up within traumatizing and sometimes dangerous practice conditions.”
Higher pay. Residents and fellows are paid a salary. They do not earn an hourly wage. When their salary is divided by 80 hours of work per week, 50 weeks per year, most residents and fellows are making less than minimum wage. When University of Massachusetts interns and residents joined the CIR union, they stated, “UMass Memorial residents are willing to work 80 hours per week because we know exceptional care is critical to community well-being, but we are significantly underpaid for doing so.”
Better benefits. Residents and fellows will desire more vacation time, top-notch health insurance benefits, and perhaps even retirement contributions.
If residents and fellows don’t receive what they seek during negotiations with the administration, what consequence can residents and fellows turn to? Will they go on strike? In May 2019, interns and residents at UCSF staged a 15-minute “Unity Break” strike as a show of solidarity and power. The Committee of Interns and Residents, which represented 1,100 of UCSF’s resident and fellow population at that time, said that management had not properly recognized the contributions of their resident and intern members and offered a package that left them underpaid and underrepresented. “UCSF has failed to meet some of the very basic demands that we have been fighting for at the table,” said Kim Carter, director of the union.
Can doctors strike? Is it ethically OK for doctors to strike? I think the answer is no. To leave patients without healthcare while doctors strike for better hours, wages, and benefits is a violation of the ethics of our healing profession. I don’t believe young doctors should be abused or squeezed into unacceptable hours, low wages, and/or poor benefits, but doctors staging a labor walkout would be a mistake. And if a union will never strike, will it ever have any real negotiating power? The CRONA (Committee for the Recognition of Nursing Achievement) nursing union at Stanford staged a strike beginning April 25, 2022, just days ago. Negotiations were successful after only one week of the strike, with the nurses gaining a tentative agreement for significant base wage increases of 5% on April 1, 2022, 2% on December 1, 2022, 5% on April 1 2023, and 5% on April 2024, in addition to other improvements in benefits, staffing, and scheduling.
I have firsthand experience with strikes. I was a laborer during three United Steelworkers of America strikes in Northern Minnesota during summer employment in taconite mines while I was in college and medical school. Blue-collar strikes are not pretty. The picket lines were brutal, and no one dared cross them. Both sides lost money as the strikes wore on, and interpersonal conflicts simmered for a long time afterward.
The idea of residents and fellows joining a union is not a new one. In 2001 TheLos Angeles Times reported a story on this topic. The article stated, “Striking will disrupt the educational progression of classes, clinical practice and testing. A student wants to come in and have some certainty that his or her three-year residency will take three years. How would they feel if suddenly they were told they wouldn’t finish on time and, whether a strike is a good idea or a bad one, that they’re not going to be able to take a board exam?” One of the doctors who joined the union at that time stated, “Change won’t come overnight, but I think it will happen. We have to stop that cowboy attitude: ‘It’s always been this way, we’re tough, we don’t complain.’ Many residents want to complain, but they’re in an environment where if they do, they’re punished. Residents have to fight for all these things and, without a union, they don’t have any legs to stand on.”
The ”cowboy attitude” refers an old-school medical education argument that sounds like this: “There’s no other way to educate doctors. It takes at least 80-100 hours per week. Even if you stay in-house every other night you miss half the good cases. When I was a resident, back in the (fill in the blank . . . 1950s, 1960s, 1970s, or 1980s), we slept in the hospital every other night and worked 120 hours per week. Now residents are complaining that 80 hours per week is too much.”
When I was an internal medicine resident in the 1980s, we stayed in the hospital on-call every third night and worked approximately 100 hours per week. My salary during my first year of residency was $16,000. On an hourly basis, this equated to $3.33 per hour. Adjusted for inflation, my 1980 salary would be $55,826, or $11.63 per hour, less than the current minimum wage.
If medical centers shorten the workweek of interns and residents to 40 hours per week from the current limit of 80 hours per week, the medical center may need to hire twice as many interns and residents or other physician surrogates to do the workload. And if the union negotiates a 10-20% increase in annual salary, the cost for interns and resident would increase further. Where will all this money come from? Most of the salaries of residents and fellows are paid for by billions of dollars of federal tax money, as medical education is subsidized by the United States government. The publication Congressional Research Sources states, “Federal support for medical residency training (a.k.a., graduate medical education [GME]) is the largest source of federal support for the health care workforce. Although the health workforce includes a number of professions, the size of the federal investment in GME—estimated at $16 billion in 2015—makes it a policy lever often considered to alter the health care workforce and impact health care access.”
Labor unions in the United States are organizations that represent workers in many industries. Labor unions grew afterCongress passed the National Labor Relations Act (NLRA) in 1935 to protect the rights of both employees and employers, to encourage collective bargaining, and to eliminate certain private sector labor and management practices which could harm the welfare of workers, businesses and the economy.
“From 1947 to 1974, hospital staff members did not have the right to unionize. . . .Congress then amended the NLRA in 1974 to include non-profit hospitals. The Committee on Labor and Public Welfare report on the amendments stated that it could find no acceptable reason why 1,427,012 employees of these non-profit, non-public hospitals, representing 56%of all hospital employees, should continue to be excluded from the coverage and protections of the Act. . . . One source of confusion involved the dubious supervisory status of professional health care providers. . . . health care professionals exercised supervisory roles and were thus excluded from the right to unionize. . . .
“In Cedars-Sinai Medical Center, the NLRB held that the residents, interns, and clinical fellows of Cedars-Sinai were not ‘employees’ within the meaning of the NLRA. Thus, they had no right to unionize. . . . The Board thus concluded that interns, residents, and clinical fellows were primarily students, noting the relationship between residents and Cedars-Sinai was primarily educational, and not an employment relationship. . . . The decision remarked that interns ‘participate in these programs not for the purpose of earning a living; instead they are there to pursue the graduate medical education that is a requirement for the practice of medicine. This statement implies that residents do not actually ‘practice medicine,’ but merely are training to do so. . . .
“In response to staunch legal criticism, the Board reversed Cedars- Sinai. Boston Medical, an oft-quoted case, involved a unit of housestaff at the Boston Medical Center (BMC) that attempted to unionize. . . . The Board overruled its precedent in Cedars-Sinai and held that medical interns and residents were both students and employees and thus were entitled to unionize. . . . The NLRB recognition of housestaff’s plight has done little to encourage unionization among medical interns and residents. . . . The residents’ dual roles, however, present extra-legal barriers to unionization which are not present in other industries. Residents spend an inordinate number of hours in the hospital and often are directly serving patients for twenty-four hours at a time. . . . the fears of Congress (and earlier fears of the American Medical Association) that unionization may compromise the doctor-patient relationship or the quality of health care residents adds another layer of complication. . . .
“The Association of American Medical Colleges (AAMC), the representative body of all accredited medical schools in the United States and Canada, as well as over 400 teaching hospitals, vehemently opposed all resident unionization efforts. . . . Offering more labor rights to medical residents would cost academic hospitals inordinate amounts of money. The cost of replacing one surgical resident with a “physician extender,” or other physician, is $210,000 to $315,000 a year. . . . the federal government is by no means an objective observer in the matter of medical residency funding and regulations. Currently, the federal government is the main financier of graduate medical education, ‘contributing $6.8 billion through Medicare, plus additional sums through the Departments of Defense and Veteran Affairs.’ The federal government is constantly looking to reduce the cost of medical care. Offering residents more control over their working conditions would likely lead them to demand more money, money that would have to come from the federal government or from private university hospitals. Thus, the government and academic hospitals are appropriate bedfellows in opposing resident labor rights.
“The Boston Medical decision made it clear that little legal basis exists to deny medical residents unionization rights or any NLRA specified rights for that matter. Thus, unless Congress amends the NLRA, no legal barriers exist to housestaff unionization. Many other internal barriers, however, hinder medical residents from acquiring labor rights. Unionization takes more effort than residents have time for and many fear unions will compromise their goals as physicians. A national survey of residents found that residents’ willingness to get involved in forming a union or serving as a member of union management was inversely proportional to the difficulty and amount of time their specialty required them to be in the hospital. Residents are accountable to their superiors for their future careers and would rather endure a few years of grueling working conditions than do anything which might compromise their careers. . . . Hospitals should give residents a real opportunity to unionize. . . . An informed, inclusive dialogue will serve to clarify legal and extra-legal barriers to accomplishing these congressional goals as well as to alleviate medical residents’ labor burdens.”
No discussion of intern and resident salaries would be complete without a disclosure of the average debt these young doctors carry. Because of the high costs of medical school and college tuition, the average medical school graduate owes $241,600 in education debt. The average medical school graduate owes six times as much as the average college graduate. You can’t blame student doctors for wanting to maximize their income as medical interns, residents, and fellows.
If there’s a silver lining in all this, it’s best described in this anecdote from my training years: After completing a 3-year residency in internal medicine, I applied for and was accepted to a second 2-year residency in anesthesiology, a field I was passionate to learn about. In the first weeks of my anesthesia residency, a former chairman of the Stanford anesthesiology department gave us a lecture and tutorial on how to intubate the trachea of a patient with the highest level of skill and ease. I hung on every word he said. I was getting a lesson from a legend, and I was collecting a salary while I was learning this craft. Image a young golf professional getting paid while he received a lesson from Jack Nicklaus. I was earning a salary while I bettered my education and became more marketable in the medical marketplace. Could I have been paid more as a resident? Perhaps. But the primary gain I made during five residency years was the investment of my time in the labor and learning which made it possible for me to work as a board-certified anesthesiologist for the past 36 years . . . and still counting.
I’m confident Stanford Healthcare and the CIF union will negotiate a successful compromise agreeable to both sides. Until that time, stay tuned, as the intersection of physician labor unions and academic medical centers will generate headlines in the days ahead.
I offer this question to my readers: Do you think it’s acceptable for unionized doctors to strike?
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Remimazolam differs from midazolam (Versed), the current most commonly used IV benzodiazepine, in that remimazolam is rapidly converted to an inactive metabolite by tissue esterases, resulting in an ultra-short onset/offset profile. Remimazolam is marketed as a powder which must be reconstituted into a liquid within its vial prior to administration.
remimazolam
propofol
For use in procedural sedation, remimazolam will not replace Versed, but rather will aim to replace propofol. The proposed advantages of remimazolam over propofol include:
Remimazolam can be completely reversed by the benzodiazepine antagonist flumazenil (Romazicon) whereas there is no reversal agent or antagonist for propofol. The only way to end the sedative effects of propofol is for an anesthesia professional to support the airway, breathing, and circulation of the patient until the drug effects of propofol wear off in time.
Remimazolam has minimal cardiac or respiratory depression. Sicker ASA III and IV patients maintain their breathing and circulation status while under remimazolam sedation.
There is no accumulative effect of remimazolam over time. Its elimination by an esterase does not slow during lengthy administration of remimazolam, as in the prolonged sedation of an intensive care unit (ICU) patient on a ventilator.
There is no burning sensation upon injecting remimazolam into a patient’s intravenous line as there is with propofol.
A non-anesthesia-professional can administer remimazolam, whereas an anesthesia professional/airway expert must administer and monitor propofol administration.
Are these advantages important? Items 1 – 5 are discussed as follows:
Non-anesthesiologists can reverse the effects of remimazolam with flumazenil if they overdose a patient, but this advantage is less important for anesthesia professionals. Anesthesiologists can manage the airway of a patient over-sedated with a benzodiazepine without need to administer a reversal agent. I’ve never administered a dose of flumazenil in my entire career, nor have most of my anesthesia colleagues.
Propofol has cardiac and respiratory depression, but in most cases these effects are minimal. Per the PDR (Physician’s Digital Reference), patients with compromised myocardial function, intravascular volume depletion, or abnormally low vascular tone (e.g. septic patients) are more susceptible to hypotension. When an anesthesiologist is present these risks are routinely managed.
For a long operating room anesthesia case (e.g. of 8 – 10 hours duration), there is no clinically significant accumulation of propofol in the bloodstream. Propofol Infusion Syndrome (PRIS), which can be potentially fatal, is a risk with prolonged propofol sedation in the ICU (SeeICU Sedation below).
The most important advantage of remimazolam is that non-anesthesiologists can safely administer remimazolam. Propofol administration requires an experienced clinician, e.g. either an anesthesiologist, a certified registered nurse anesthetist (CRNA), or an emergency medicine physician. Per the American Society of Anesthesiologists: “The practitioner administering propofol for sedation/anesthesia should, at a minimum, have the education and training to identify and manage the airway and cardiovascular changes which occur in a patient who enters a state of general anesthesia.”
The disadvantages of remimazolam compared to propofol include:
Remimazolam is sold as a powder and must be reconstituted into a liquid before it can be injected intravenously.
Remimazolam is currently approved as an anesthesia drug in Japan and South Korea, for intensive care unit sedation in Belgium, but only for procedural sedation in the United States, China, and Europe. In total, there are four possible applications for remimazolam. Let’s examine the pros and cons of using remimazolam in these four applications:
Preoperative sedation. Since midazolam (Versed) was approved in 1982, a standard anesthesia practice has included a 2 mg dose of Versed prior to surgery to calm a patient’s anxiety. In the 1980s my anesthesia chairman at Stanford received a letter from a postoperative patient in which she complained of being awake and very anxious in the operating room prior to the anesthetic for her breast cancer surgery. Our chairman lectured to us, “Do you know many patients are nervous prior to their anesthesia and surgery? Every one of them. We have an excellent drug for relieving preoperative anxiety, and that drug is Versed. Use it! Give your patient a dose of Versed before they enter the operating room. There are few significant side effects of one dose of Versed. Use it!” Will remimazolam replace Versed for this application? No. There is no advantage of the new, shorter acting, more expensive remimazolam over Versed for preoperative sedation.
Sedation for short procedures. This is the FDA-approved application for remimazolam in the United States. An example procedure would be a colonoscopy. Will remimazolam be widely used for colonoscopies in the near future? No, I doubt it. The cost increase is the main disadvantage. See the typical drug acquisition costs for three alternative sedation recipes for colonoscopy below:
The increased cost per case is $23.27 for remimazolam over propofol.
The increased cost per case is $36.50 for remimazolam over fentanyl+Versed.
If a busy endoscopy center does 100 colonoscopies cases per week, the cost increase is $2327 per week for remimazolam over propofol, or $3650 per week for remimazolam over fentanyl+Versed. These are a prohibitive cost increases with no clear added benefits. The only way remimazolam could result in cheaper sedation costs would be if a healthcare system was looking to eliminating the cost of paying for an anesthesia provider for these procedures. The pairing of remimazolam+gastroenterologist sedation rather than propofol+anesthesiologist sedation could afford significant cost savings for a healthcare system.
3. Total intravenous anesthesia (TIVA). TIVA could include a continuous infusion of the ultra-short-acting narcotic remifentanil plus a continuous infusion of the ultra-short-acting remimazolam. An alleged advantage of this technique could be the fast offset time of these two TIVA anesthetic agents. I doubt this technique will gain market share. It’s far easier to turn on the knob of a sevoflurane vaporizer than to load and manage two TIVA-syringe pumps. As well, the added expense of a prolonged infusion of remimazolam will be prohibitive.
This potential advantage of remimazolam over propofol will be offset by the increased expense of hours or days of remimazolam utilization in an ICU sedation situation. ICU sedation with fentanyl and older benzodiazepines such as Ativan will have the advantage of a lower cost.
In the hands of an anesthesiologist, propofol is an elegant and almost ideal intravenous sedative, with the advantages of rapid onset, rapid offset, inexpensive generic pricing, minimal cardiovascular/respiratory depression, and lack of nausea. Propofol administration does carry the risks of upper airway obstruction, hypoventilation, and low oxygen saturation, but when an anesthesiologist is present these risks are minimal.
If a healthcare organization doesn’t want to employ an anesthesiologist or a CRNA for a case which requires procedural sedation, then remimazolam may be an excellent sedative choice. Will gastroenterologists prefer to sedate patients with remimazolam plus fentanyl without an anesthesiologist? Or will they prefer to have an anesthesiologist present to administer propofol? Expect gastroenterologists to prefer the latter, because they are not only off-loading the task of sedating the patient, they are also off-loading the risks of managing the patient’s medical co-morbidities, which can be significant if a patient has lung disease, cardiac disease, morbid obesity, or obstructive sleep apnea.
The remimazolam story suggests one of my favorite anecdotes: A former Stanford Chairman of Anesthesiology and friend of mine who left the university in 2006 to become a pharmaceutical company executive, first at Novartis and then at AstraZeneca. Ten years ago, when I asked him what new anesthesia drugs were in the pipeline, he answered, “None, and there probably will be very few new ones. The drugs you have now are inexpensive generic drugs, and they work very well. The research and development costs to bring a new anesthetic drug to market are prohibitively expensive, and unless that new drug is markedly better, it will not push the inexpensive generic drugs out of use.”
Remimazolam will capture a very small market in the United States. Until remimazolam becomes an inexpensive generic drug, I see it as a medical white elephant rather than a wonderful anesthetic advance.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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How soon will we see robotic anesthesia in our hospitals and surgery centers? In the past three decades the high-tech revolution introduced the internet, the laptop computer, the iPhone, Google, and global positioning satellites. Most of these discoveries originated in Silicon Valley, just miles outside Stanford University Hospital where I’ve been working for the past 42 years. Our medical world inside the hospital has changed more slowly. We’ve seen advances in noninvasive surgery, fiberoptic scopes, transplantation science, cancer therapeutics, and mega healthcare delivery companies. But what’s new in anesthesia the last 30 years? Relatively little. The Glidescope, sugammadex, ultrasound-guided blocks, and the time-consuming Electronic Medical Record arrived, but we typically administer the same medications, use the same airway tubes, and watch the same vital signs monitors as we did in the 1990s.
Why have there been no new anesthetics? Let me tell you a story: A former Stanford Chairman of Anesthesiology and friend of mine left the university in 2006 to become a pharmaceutical company executive, first at Novartis and then at AstraZeneca. Ten years ago, when I asked him what new anesthesia drugs were in the pipeline, he answered, “None, and there probably will be very few new ones. The drugs you have now are inexpensive generic drugs, and they work very well. The research and development costs to bring a new anesthetic drug to market are prohibitively expensive, and unless that new drug is markedly better, it will not push the inexpensive generic drugs out of use.”
Is the same true for anesthesia devices? Are proposed anesthetic robots too expensive to design, test, and manufacture? Can they be brought to market to assist current anesthesia providers? Can they be brought to market to replace any anesthesia providers? Keep these economic questions in mind as we review the current science of robotic anesthesia.
Will we live to see anesthesiologists replaced by technology? The following three pictures depict fictional anesthesia robots:
fictional medical robots
But this is what real anesthesia robots look like:
real anesthesia robots
An outline of the types of robotic anesthesia is as follows:
PHARMACOLOGIC ROBOTS
MECHANICAL ROBOTS PERFORMING PROCEDURES
DECISION SUPPORT ROBOTS
PHARMACOLOGIC ROBOTS:
In 2012 a United States national marketing firm contacted me to seek my opinion regarding an automated device to infuse propofol. The device was the Sedasys®-Computer-Assisted Personalized Sedation System, developed by Johnson and Johnson/Ethicon. The system incorporated an automated propofol infusion device, along with standard ASA monitors, including end-tidal CO2, into a device to be used to provide conscious sedation for GI endoscopy.
The SEDASYS system
The Sedasys unit infused an initial dose of propofol (typically 30 – 50 mg in young patients) over 3 minutes, and then began a maintenance infusion of propofol at a pre-programmed rate (usually 50 mcg/kg/min). If the monitors detected signs of over-sedation, that is, falling oxygen saturation, depressed respiratory rate, or a failure of the end-tidal CO2 curve, then the propofol infusion was stopped automatically. In addition, the machine talked to the patient, and at intervals asked the patient to squeeze a hand-held gripper device. If the patient was non-responsive and did not squeeze, the propofol infusion was automatically stopped.
The planned strategy was to have gastroenterologists complete a weekend educational course to learn: that Sedasys was not appropriate if the patient is ASA 3 or 4 or had severe medical problems; that Sedasys was not appropriate if the patient had risk factors such as morbid obesity, a difficult airway, or sleep apnea; and gastroenterologists were taught the airway skills of chin lift, jaw thrust, oral airway use, nasal airway use, and bag-mask ventilation.
I did not recommend the device be FDA-approved, as I saw the potential of inappropriate patients with obesity or sleep apnea slipping through the screening process, as well as the risk that an over-sedated patient could lose their airway and the gastroenterologist would not be able to rescue them, seeing as propofol has no reversal agent.
With only one prospective clinical trial, the United States Food and Drug Administration did approve the device in 2013. There was limited clinical use of Sedasys, and Ethicon announced in March 2016 that it was pulling Sedasys from the market.
If a patient became too “light” during a procedure, the Sedasys system was not capable of increasing the depth of the sedation.
Both patients and endoscopists expected deep general anesthesia, not moderate sedation.
Gastroenterologists were ill-equipped to shoulder the responsibility of general anesthesia and airway management.
From the failure of Sedasys it was clear that further refinement in technology and drug use was needed. That refinement was the development of closed-loop devices. A closed-loop control system is a set of mechanical or electronic devices that automatically regulates a process variable to a desired state or set point without human interaction. The cruise-control on your automobile is an example of closed-loop feedback control of driving speed.
In anesthesia, closed-loop devices can infuse the medications propofol and remifentanil, with the rate of the infusions guided by a bispectral (BIS) monitor of EEG (electroencephalography) activity. Propofol is an ultra-short-acting hypnotic drug, and remifentanil is an ultra-short-acting narcotic. Administered together, these drugs induce total intravenous anesthesia (TIVA).
A closed-loop system can infuse these two drugs automatically. A BIS monitor calculates a score between 0 and 100 for the patient’s level of unconsciousness, with a score of 100 corresponding to wide awake and 0 corresponding to a flat EEG. A score of 40 – 60 is considered an optimal amount of anesthesia depth. A computer controls the infusion rates of two automated infusion pumps containing propofol and remifentanil. The infusion rates depend on whether the measured BIS score is higher or lower than the 40- 60 range. Researchers in Vancouver, Canada expanded this technology into a device called the iControl-RP, where the initials RP stand for remifentanil and propofol. In addition to the BIS monitor, the iControl-RP monitored the vital signs of blood oxygen level, heart rate, respiratory rate, and blood pressure to determine how much anesthesia to deliver.
iControl-RP robot
In a single-blind randomized study published in Anesthesiology in 2015, 42 patients were randomized to the closed-loop iControl-RP group or to a manual group. The results showed the percentage of time with BIS40-60 was greater in the closed-loop group (87%) vs. the manual group (72%). The number of perioperative adverse events and the length of stay in the postanesthesia care unit were similar. The conclusion of the study was that automated control of hypnosis and analgesia guided by the BIS was clinically feasible.
This study led to an article in the TheWashington Post in 2015, in which one of the machine’s co-developers, Dr. Mark Ansermino said, “We are convinced the machine can do better than human anesthesiologists.” The device had been used on 250 patients at that time. The iControl-RP team struggled to find a corporate backer for its project. Dr. Ansermino told TheWashington Post, “Most big companies view this as too risky.” He believed a device like this was inevitable. “I think eventually this will happen,” Ansermino said, “whether we like it or not.”
A second pharmacologic robot named McSleepy used three syringe pumps to control the three components of general anesthesia (hypnosis, analgesia, and neuromuscular block) in an automated closed-loop anesthesia drug delivery system. Each component had specific monitoring: BIS; AnalgoScore (an-AL-go-score = a pain score derived from the heart rate and mean arterial pressure) which was used as the control variable to titrate the effective dose of remifentanil; and the train of four (TOF), which was a measure of the twitch strength of a muscle when its peripheral nerve was electrically stimulated.
The control of depth of anesthesia under McSleepy (blue) or manual (green)
The McSleepy system also showed faster extubation times than manually administered anaesthesia.
A second McSleepy study in the British Journal of Anaesthesia in 2013 showed an application in telemedicine. The remote control of general anesthetics was successfully performed between two different countries (Canada and Italy). Twenty patients underwent elective thyroid surgeries, with a master-computer in Montreal and a slave-computer in Pisa, demonstrating the feasibility of remote telemedicine control of anesthesia administration.
II. MECHANICAL ANESTHESIA ROBOTS
Ma’s mask ventilation robot
The first example is a machine designed to provide mask ventilation, as described in the paper “Novel Anesthesia Airway Management Robot for Robot Assisted Non-invasive Positive Pressure Mask Ventilation,” Published by Dr. Ma et al, from China. Ma designed a robot equipped with two snake arms and a mask-fastening mechanism to facilitate trachea airway management for anesthesia. (PIC) The two snake arms were designed to lift a patient’s jaw. The mask-fastening mechanism was used to fasten and hold the mask onto a patient’s face. A joystick control unit managed both the lifting and fastening force. To date this system has not been used on humans, but the device was proposed as a method to perform non-invasive mask positive pressure ventilation via a robotic system.
The Kepler Intubating System
In 2012 Dr. Hemmerling at McGill University in Montreal published a paper in Current Opinions in Anaesthesiology, describing the Kepler Intubation System. The Kepler Intubation System consisted of a remote-control joystick and intubation cockpit, linked to a standard videolaryngoscope via a robotic arm. (PIC) Ninety intubations were performed on a mannequin with this device. The first group of 30 intubations was performed with the operator in direct view of the mannequin. The second group of 30 intubations was performed with the operator unable to see the mannequin. The third group of 30 intubations were performed via semiautomated intubations during which the robotic system replayed a tracing of a previously recorded intubation maneuver. All intubations were successful on the first attempt, with the average intubation times between 41 and 51 seconds for all three groups. The study concluded that a robotic intubation system can complete successful remote intubation within 40 to 60 seconds.
The Magellan Nerve Block System
In 2013 Dr. Hemmerling published the study “First Robotic Ultrasound-Guided Nerve Blocks in Humans Using the Magellan System” in Anesthesia & Analgesia. The Magellan system consisted of three main components: a joystick, a robotic arm, and a software control system. After localization of the sciatic nerve by ultrasound, 35 ml of bupivacaine 0.25% was injected by the robot. Thirteen patients were enrolled. The nerve blocks were successful in all patients. The nerve performance time was 164 seconds by the robotic system, and 189 seconds by a human practitioner. The Magellan System was the first robotic ultrasound-guided nerve block system tested on humans.
III. DECISION SUPPORT ROBOTS
A decision-support robot can recognize a crucial clinical situation that requires human intervention and, when allowed by the attending clinician, may administer treatment. It seems likely that cognitive robots which follow algorithms can increase patient safety.
In August 2021 Dr. Alexandre Joosten, an anesthesia professor in Brussels, Belgium and Paris, France, published “Computer-assisted Individualized Hemodynamic Management Reduces Intraoperative Hypotension in Intermediate- and High-risk Surgery: A Randomized Controlled Trial” in Anesthesiology. This study tested the hypothesis that computer-assisted hemodynamic management could reduce intraoperative low blood pressure in patients undergoing intermediate- to high-risk surgery. This prospective randomized single-blinded study included 38 patients undergoing abdominal or orthopedic surgery. All patients had an indwelling radial arterial catheter to monitor blood pressure continuously. A closed-loop system titrated a norepinephrine infusion based on the blood pressure, and a second separate decision support system infused mini-fluid challenges when low blood pressures were recorded. Results showed the time of intraoperative hypotension was 1.2% in the computer-assisted group compared to 21.5% in the manually adjusted goal-directed therapy group (P < 0.001). The incidence of minor postoperative complications was the same between groups (42 vs. 58%; P = 0.330). The mean stroke volume index and cardiac index were both significantly higher in the computer-assisted group than in the manually adjusted goal-directed therapy group (P < 0.001). The study’s conclusion was that this closed-loop system resulted in a significant decrease in the percentage of intraoperative time with a low mean arterial pressure.
The article described how thousands of Alexa-enabled devices are in use in hundreds of hospitals in America. Amazon’s Alexa functions as a digital personal assistant whose voice-powered innovation connects patients with their healthcare team members. Patients who are confined to bed can use their voice to communicate directly to a nurse’s smartphone. An Alexa device is positioned near the bed at Cedars-Sinai Medical Center in Los Angeles, making it easy to call for nursing help. (PIC) Alexa can also connect healthcare providers to their patients. Doctors or nurses can appear virtually in a patient’s room on the Alexa Show’s video screen and assess the needs of that patient. I expect voice-activation to link healthcare providers with medical robots in the future.
PROBLEMS WITH ROBOTS REPLACING ANESTHESIA
The medical publications referenced above demonstrate that robotic anesthesia devices exist, yet none of them are in common use at this time. The current and proposed robotic devices are only small steps toward replacing anesthesiologists, because anesthetizing patients requires far more expertise than merely titrating drug levels or performing a solitary mechanical procedure.
Anesthesia management consists of a wide variety of skills:
preoperative assessment of a patient’s medical problems
successful mask ventilation of an unconscious patient (in most cases) followed by placement of an airway tube
diagnosis and treatment of any medical complication that occurs as a result of the anesthesia or the surgical procedure
removal of the airway tube at the conclusion of most surgeries, and
the diagnosis and treatment of postoperative medical complications
Successful robotic anesthesia devices may eventually eliminate the repetitive aspects of anesthesia management. You may see robots assisting anesthesia providers in the coming decades, depending on the economic viability of the technology.
Will the intrusion of a robot into anesthesia care be a welcome event? When you’re a patient, do you desire a caring, empathetic human attending to you, or do you desire an algorithm?
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Underwater general anesthetics of 3 hours duration? See it in The Rescue, a new National Geographic Documentary Film directed by Jimmy Chin (winner of the 2018 Academy Award for Best Documentary Feature for Free Solo). The Rescue details the miraculous extraction of 12 boys and their coach from a flooded Thailand cave in June and July of 2018. The Rescue required 13 underwater general anesthetics delivered by an anesthesiologist and maintained by non-medical cave divers during their 3-hour swim to the mouth of the cave. How did this once-in-history anesthetic tour de force come about? You can watch the movie—a favorite for this year’s Oscar for Best Documentary—on Disney+ for their $7.99 monthly fee. This column explains the specifics as to how anesthesiology innovation saved thirteen lives in The Rescue.
The site of The Rescue was the Tham Luang Nang Non cave in Chiang Rai Province in northern Thailand. Twelve boys of ages 11 – 16 from the Wild Boar soccer team and their coach entered the cave for a birthday celebration. June monsoon rains hit and flooded the entrance of the cave, trapping all thirteen inside.
The boys were trapped at the left of this diagram. The entrance to the cave is at the right.
The synopsis of The Rescue follows this timeline:
Day 1 – Trials of gas-powered generators to pump the water out of the cave fail to lower the water level.
Day 2 – The Thai Navy Seals arrive on site. They attempt scuba diving into the cave but abort their efforts because of low visibility and difficult access. They were only able to advance 200 meters into the cave. None had experience diving into dark narrow caves. John Volanthen, an information technology consultant who does cave diving as a hobby, shows them a map of the long tortuous cave route, and surmises that the boys are trapped about 2 kilometers into the cave. Richard Stanton, a retired middle-aged British firefighter who is also an expert in cave diving, is alerted to the predicament, and flies to Thailand to help.
Day 5 – Stanton assembles a collection of his friends who are fellow cave divers. These men have real world jobs such as electricians, contractors, mechanics, and consultants, but are experienced in underwater cave exploration. At first, the Thai Navy Seals will not allow the cave divers to attempt a rescue because they deem it is too dangerous. Eventually the Thai Seals consent to let the cave divers proceed. Stanton describes their passage as scuba diving against a raging river of white water, with the added problem of poor visibility. They surface at the first air-filled chamber inside the cave, and instead of finding the boys they find four pump workers who were unknowingly trapped inside the cave. The cave divers swim the pump workers out, sharing their scuba regulators as they swim, but find the pump workers are easily panicked in the dark cold underwater conditions, and the passage out is very difficult. Their entire swim rescue of these men takes only 30 to 40 seconds, yet Stanton describes the ordeal as “an underwater wrestling match.”
Day 7 –Rain continues and the water levels rise. Hundreds of people surround the mouth of the cave, and worldwide media coverage is ongoing.
Day 10 – The cave divers continue their attempts to explore the length of the cave. They extend a rope behind them to trace their route back to the outside world. After several hours of traversing the narrow route, including passing through several air chambers above water, they reach a chamber where the atmosphere smells pungent. They fear they have located the rotting flesh of decomposing bodies. Instead they shine a light into the chamber and see 13 people—the Thai boys and their coach—sitting on the rocky floor. They are skinny and frightened, but alive. They’ve had no food for 10 days and have existed by drinking the water from the cave. The cave divers return to the mouth of the cave and announce that the boys are alive.
Day 12 – The divers follow the rope back to the boys and bring them power gel food and foil blankets. Their plan going forward is unclear. There appears to be no way to swim the boys out for the 3-hour underwater journey to the mouth of the cave. One option is to wait until October (four months) until the monsoon season is over, and the cave is no longer flooded. A second option is to somehow drill down to where the boys are trapped. A third option is to pump out millions of gallons of water out of the cave, but this is also deemed impossible. Another cave diver friend of Stanton’s is Dr. Richard Harris, who lives and works in Australia. Dr. Harris is an anesthesiologist. The team of cave divers telephone him and ask if the boys can be anesthetized for 3 hours to be extracted underwater. His initial answer is no, that this would be impossible.
At the same time, the divers bring an oxygen analyzer into the cave and discover that there is only 15% oxygen left in the atmosphere where the boys are trapped. Normal room air contains 21% oxygen, and 15% oxygen is considered an eminent threat to life for the boys. Immediate action is necessary.
Day 14 – Dr. Harris arrives at the cave. He and his cave diver colleagues come up with a plan to anesthetize and extract the boys, but there is a new problem: The Thai government does not want them to attempt the rescue. The government fears the boys will all die in the futile attempt. Enter Josh Morris, a cave diver who speaks Thai. He explains the facts and the threat of the low oxygen atmosphere to the government authorities, and convinces them there is no time to waste and that there is no other workable plan. The government agrees to let the cave divers proceed.
Day 15 – The rescue plan is as follows: Divers will swim into the cave to the chamber where the boys are located. The divers will transport an extra oxygen cylinder, a full-face dive mask and regulator, and a dive suit for each boy. They will also carry three medications: 1) Xanax, an oral anti-anxiety pill in the Valium family of benzodiazepines; 2) ketamine, an injectable general anesthetic drug, carried in a syringe-and-needle setup; and 3) atropine, an injectable drug which dries up oral secretions (necessary because ketamine can cause excessive salivation significant enough to choke off breathing). When the cave divers arrive at the chamber where the boys are situated, they dress the first boy in a dive suit complete with a rubber head-covering. Dr. Harris then administers the Xanax pill and the intramuscular injections of ketamine and atropine. After the boy loses consciousness, they tie the boy’s hands behind the boy’s back and apply the full-face oxygen dive mask to keep the water out. The boy is placed in the water atop a full oxygen cylinder, and a diver guides the boy and the cylinder under the water. This diver clings to the rope as he begins the 3-hour journey back toward the cave entrance. There are multiple air chambers on the route back to the entrance. At each air chamber, the diver surfaces and assesses if the boy is still alive and breathing, and whether the boy is anesthetized deeply enough. If the boy is twitching, the diver injects more ketamine. Keep in mind this diver is not a doctor—he has been taught by Dr. Harris to inject more drug if the boy seems to need more sedation. This process is repeated for four boys the first day and is successful. All four reach the surface, alive and anesthetized, and are transported to a nearby hospital.
Day 17 – The process is repeated and four more boys are successfully extracted.
The Rescue is riveting and suspenseful, and ultimately worth the one hour 45 minutes and the $7.99 you’ll invest in it.
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Here’s the Anesthesia Consultant analysis of the medical circumstances in The Rescue:
In an operating room, anesthesia is typically delivered as a gas (e.g. sevoflurane), or intravenously. Neither gas anesthesia nor intravenous anesthesia is possible in an underwater cave rescue. Ketamine is the only general anesthetic drug which can be injected. Ketamine can be injected either into an IV (e.g. in an operating room by an anesthesiologist) or into a muscle (e.g. in a cave in Thailand). Ketamine has the advantages of quick onset and a lack of respiratory depression—that is, ketamine will not stop a patient’s breathing. But if a patient becomes over-sedated it’s possible they will have upper airway obstruction which can lead to inadequate ventilation, so ketamine administration typically needs to be administered by an anesthesia professional who monitors the patient’s breathing—unless you’re rescuing kids in a cave. Ketamine also has theses disadvantages: It results in a relatively slow wake up (compared to propofol and/or sevoflurane gas); it causes markedly increased saliva production (which is why we need to administer atropine, a secretion-blocking anticholinergic drug—along with ketamine); and ketamine can cause vivid bad dreams—for this reason we routinely give an IV benzodiazepine such as Versed along with ketamine. Re-dosing of ketamine was required because the drug’s half-life (the time it takes for the total amount of ketamine in the body to be reduced by 50%) is about 2.5 hours in adults. Dr. Harris couldn’t be with every boy en route, which is why he had to train the other cave divers how to inject ketamine for redosing.
Dr. Harris could have chosen to use an injection of intramuscular Versed instead of Xanax (the oral benzodiazepine used in The Rescue). A disadvantage with oral Xanax is its slow onset time. It’s unlikely the Xanax began to work until it was absorbed from the stomach and carried by the bloodstream to the brain, which likely took thirty minutes or more.
The choice of full-face dive masks (FFMs), capable of maintaining constant positive airway pressure (CPAP) during the anesthetics, was brilliant. All acute medical care, be it in an operating room, an intensive care unit, an emergency room, a battlefield, or a cave, follows the priority order of A-B-C, or Airway- Breathing-Circulation. The problems of keeping the airway open, as well as keeping oxygenation and ventilation intact, were daunting challenges underwater. There were no research articles and no textbooks to tell the cave divers how to deal with this situation. They used their best strategy and made their best guess, and it was successful. If excessive water had leaked into the mask, a boy could drown.
full face dive mask
Fortunately all the boys and their coach were slender (per the video footage) and had low body-mass-indexes (BMIs). A patient with a low BMI typically has an easy airway, and would have a lower chance of obstructing their upper airway during a 3-hour underwater general anesthetic. An overweight patient would probably not have survived a 3-hour underwater general anesthetic. As well, all the boys and their coach were young and healthy with normal hearts and lungs. If they had been older, with any abnormal cardiac or respiratory function, they may not have survived the 3-hour underwater general anesthetic.
The Thai boys in the cave
It’s striking that the boys could survive for two weeks with only water and no food. Hydration is critical—no one can survive two weeks without water—but food was not imperative for this length of time. They survived without calories for two weeks, but humans can only survive for about three days without water.
Hypothermia, or low body temperature, was a risk during the underwater rescue. Anesthetized patients have no muscle movement and are unable to generate any body heat in the cold water. The scuba suits and hoods were aimed at minimizing the temperature drop while the boys were anesthetized.
No one monitored the vital signs of the boys during their 3-hour underwater general anesthetics. General anesthetics always require monitoring of these parameters: heart rate, oxygen saturation, blood pressure, ECG, respiratory rate, temperature, and end-tidal carbon dioxide expiration. In an underwater cave anesthetic, none of this was possible. Luckily the ketamine anesthesia as administered must have kept all the vital signs within acceptable limits.
The oxygen concentration in the atmosphere of the cave was only 15%, far lower than the normal room air concentration of 21% we’re all breathing right now. This oxygen concentration of 15% is roughly equivalent to the oxygen concentration atop a mountain at 10,000 feet of altitude. The boys tolerated the gradual decrease of the oxygen level within the cave from 21% to 15% over 12 days without any brain damage or any damage to a vital organ system. An acute decrease from 21% to 15% may have caused low blood oxygen—hypoxia—and organ damage. During anesthetics in an operating room, anesthesiologists commonly administer at least 40-50% oxygen—a higher concentration than in room air—as an extra margin of safety.
Will this sort of underwater anesthetic cave rescue ever happen again? Perhaps. The blueprint for a successful result is here in this movie. The science of the full dive face masks in this rescue was published in the medical journal Diving and Hyperbaric Medicine in the article Deep anaesthesia: The Thailand cave rescue and its implications for management of the unconscious diver underwater.
The film The Rescue documents a remarkable feat of emergency medicine and emergency anesthesia care. I recommend you see the movie, and I hope you’ll understand the medical care better because of the discussion presented above.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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TheAnesthesiaConsultant.com presents its 2022 ranking of The Top 10 Living Anesthesiologists. These individuals made significant original contributions to the practice and/or education of anesthesiologists throughout the world. As a physician anesthesiologist who has attended to patients in the 1980s, 1990s, 2000s, 2010s, and now the 2020s, in both university and community settings, I’m uniquely qualified to identify and honor the leaders in our field over this time.
#4. Lee Fleisher MD, University of Pennsylvania. Dr. Fleisher authored the textbooks Anesthesia and Uncommon Diseases, and Complications in Anesthesia, as well as 421 publications in major medical journals, with a concentration in the preoperative evaluation of the surgical patient. His most noteworthy contribution was the classic paper Preoperative Cardiac Evaluation for Noncardiac Surgery, published in 1992 in Anesthesia and Analgesia. This paper set the standards for how anesthesiologists should approach the preoperative cardiac evaluation of their patients. Dr. Fleisher was the long-term Chair of the Department of Anesthesiology and Critical Care (2004-2020), and the Robert Dunning Dripps Professor of Anesthesia at the University of Pennsylvania Health System. He is currently the Chief Medical Officer and Director of The Center for Clinical Standards and Quality at the Centers for Medicare & Medicaid Services (CMS), a part of the Department of Health and Human Services (HHS).
NOTE: This list of The Top 10 Living Anesthesiologists does not contain any females or diversity. All ten nominees are white males. Such was the state regarding the advances in our specialty over the past five decades. Future lists may honor females or diversity, depending on the state of career achievements over the coming years.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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Three days ago, I was giving anesthesia for six consecutive colonoscopy patients. Following my first case, I checked my phone and discovered that the President of the United States Joe Biden was having a colonoscopy at Walter Reed Medical Center that very morning. The headlines stated that for the first time, temporary acting presidential power was being turned over to a woman, Vice President Kamala Harris, during the time of President Biden’s colonoscopy anesthesia.
I mentioned this to the gastroenterologist I was working with that day, and he asked, “How long do you think he will be unable to make decisions as the President? We tell our patients not to drive the rest of the day, and not to make any important life decisions after their general anesthetic. Biden has the most difficult and most important job on Earth. When can he return to duty?”
I answered, “My guess is that he’ll have the same propofol anesthetic we’re administering today. The procedure will last thirty minutes, he’ll begin to awaken five minutes after the propofol is discontinued, and within an hour he’ll feel clear-headed.” The gastroenterologist was dubious that the leader of the free world would be alert enough to resume power only one hour after receiving propofol. Joseph Biden was one day short of his 79th birthday when the colonoscopy took place. Later that morning the news services reported that the President had transferred presidential powers to Kamala Harris at 10:10 a.m. EST and resumed his presidential powers at 11:35 a.m., a mere 1 hour and 25 minutes later.
A note from an anesthesiologist to the comedy writers: No one uses “gas” for anesthesia for a colonoscopy. The anesthetic is solely from intravenous (IV) drug(s).
I have no specific knowledge of what anesthetic drug regimen the President received for his colonoscopy, but more likely than not he received propofol. Anesthesia for colonoscopy is typically administered so that patients have no awareness during this procedure, a procedure which does not involve surgical pain, but rather involves the uncomfortable entrance of a 66-inch-long flexible hose, one-half-inch in diameter, into their anus, rectum, and colon.
For the quickest recovery after colonoscopy, one option is no anesthesia at all. Very few patients sign up for a colonoscopy without any intravenous anesthesia. The press reports about Biden’s colonoscopy stated that he had anesthesia, so let’s discount the option that he had the procedure while awake.
Propofol for colonoscopy leads to a quicker wakeup, a quicker discharge home, and less hangover. Virtually every surgical general anesthetic in the United States includes propofol, and anesthesiologists are experts at the administration and pharmaceutical properties of the drug. Propofol is an intravenous nonbarbiturate anesthetic which induces anesthesia quickly and provides a rapid emergence from anesthesia. The onset of action is within 20 – 40 seconds. The anesthesia provider for a colonoscopy will continue administering IV propofol until the procedure is over. A typical colonoscopy will last 20 – 40 minutes, depending on whether the gastroenterologist needs to take extra time to remove any colonic polyps. In Biden’s case, a single 3 mm benign-appearing polyp was identified and removed.
Propofol’s pharmacokinetics are described by two phases:
In the first phase (red curve), the plasma concentration decreases rapidly because the drug redistributes, or spreads, out of the bloodstream into other tissues of the body. The half–life of this fast redistribution is only 2 – 8 minutes, meaning the concentration of propofol in the bloodstream is halved every 2 to 8 minutes. This first phase explains the quick transition to wakefulness up after the drug is stopped. The second phase (black curve) is the elimination of propofol from the body. The half-life time of this elimination from the body is 4 – 7 hours (reference: MILLER’S ANESTHESIA, 9thedition, chapter 23 on Intravenous Anesthetics).
The graph below depicts the timeline after propofol is discontinued. After a one-hour infusion, the concentration of propofol in the blood drops to near zero within 30-40 minutes.
THE PROPOFOL CONCENTRATION APPROACHES ZERO 40 MINUTES AFTER THE END OF INFUSION
The website PDR.net affirms this, stating that “Recovery from anesthesia is rapid (8 to 19 minutes for 2 hours of anesthesia) and is associated with minimal psychomotor impairment.” The PDR also states that “The elimination half-life of 3 to 12 hours is the result of slow release of propofol from fat stores. About 70% of a single dose is excreted renally (by the kidneys) in 24 hours.”
While the President would be awake one hour after receiving 30 minutes of propofol, and the blood concentration would be minimal, it still takes 24 hours for 70% of a single dose of propofol to be excreted by the kidneys. Therefore, one hour after the propofol was discontinued, even though the blood concentration was minimal, a significant amount of the drug would still be in the President’s body.
I’ve had propofol anesthesia for a colonoscopy, and I can attest that I woke up promptly and was in an automobile heading home within 45 minutes after the end of the procedure. I felt alert, albeit a bit woozy, after 60 minutes of recovery time. Did I feel it would have been safe for me to resume my duties administering general anesthetics to patients at that time? No. Would a major American airline allow one of its pilots to fly passengers at that time? No. Would the U.S. Army allow a general to command thousands of soldiers at that time? I doubt it.
One hour after a propofol colonoscopy anesthetic, the President would be awake enough to converse and give a “thumbs up.” Would he be alert enough at that point to make decisions regarding the nuclear football, a potential attack on Taiwan by mainland China, or a terrorist attack on a major United States city? Was this nearly 79-year-old man safe to make all the acute decisions the United States President could have to make, only one hour after discontinuing propofol?
The Mayo Clinic website states that, “After the exam (colonoscopy), it takes about an hour to begin to recover from the sedative. You’ll need someone to take you home because it can take up to a day for the full effects of the sedative to wear off. Don’t drive or make important decisions or go back to work for the rest of the day.”
Was Biden fit to run the country 55 minutes after his colonoscopy anesthetic?
Hmmm. The decision as to whether he was recovered enough to resume running the country . . . was a decision made by President Biden’s doctors on that day.
Richard Novak, MD is a Stanford physician board certified in anesthesiology and internal medicine.Dr. Novak is an Adjunct Clinical Professor in the Department of Anesthesiology, Perioperative and Pain Medicine at Stanford University, the Medical Director at Waverley Surgery Center in Palo Alto, California, and a member of the Associated Anesthesiologists Medical Group in Palo Alto, California. emailrjnov@yahoo.com
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The most important changes are identified by examining the 2013 and the 2022 algorithms side by side. Let’s look at the 2013 flow chart algorithm and compare it to the 2022 flow chart algorithm below:
An astronaut en route to Mars develops severe abdominal pain, nausea, and vomiting. A fellow crew member examines him and finds significant tenderness and guarding in the right lower quadrant of his abdomen. The crew members teleconference with physicians on Earth, with a 20-minute communication delay because of the 140-million mile distance between them. The physicians confirm a probable diagnosis of appendicitis. Because the spaceship is more than 200 days away from Earth, the physicians instruct the crew to proceed with surgery and anesthesia in outer space.
