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THE NEW 2022 ASA DIFFICULT AIRWAY ALGORITHM

THE ANESTHESIA CONSULTANT 1 Comment
THE ANESTHESIA CONSULTANT
THE ANESTHESIA CONSULTANT
Physician anesthesiologist at Stanford at Associated Anesthesiologists Medical Group
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 American Society of Anesthesiologists (ASA) just published a 2022 update on their ASA Difficult Airway Algorithm Guidelines. The 2022 document is a revision of the 2013 publication “Practice guidelines for management of the difficult airway: A report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway.” The 2022 ASA Difficult Airway Algorithm Guidelines are 51 pages in total.

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:

THE 2013 ASA DIFFICULT AIRWAY ALGORITHM

THE 2022 ASA DIFFICULT AIRWAY ALGORITHM

Note these major changes from 2013 to 2022:

  1. The top third of the 2022 algorithm lists factors which direct the anesthesiologist to perform awake intubation. The reason for this change is undoubtably the wisdom of utilizing awake intubation when a significant risk of a difficulty airway exists. There are minimal airway risks when a patient is awake, and the benefit of placing the endotracheal tube in a difficult airway patient while the patient is awake is immense. When we give mock oral board examinations to anesthesia residents at Stanford, and we describe to the examinee that the patient has a difficult airway, the answer of “I’d do an awake intubation” is hard to criticize and almost never leads to a catastrophe. In contrast, inducing general anesthesia prior to intubation in these patients can lead to a “Can’t intubate-can’t oxygenate” emergency, which can lead to a cardiac arrest and possible anoxic brain damage.
  2. The text highlighted in red in the 2022 document is both new and vital. The first of these is “OPTIMIZE OXYGENATION THROUGHOUT,” under the pathway INTUBATION ATTEMPT WITH PATIENT AWAKE, with the footnote 2Low- or high-flow nasal cannula, head elevated position throughout procedure. Noninvasive ventilation during preoxygenation. The message is to keep oxygen flowing via nasal cannula throughout airway management attempts to minimize hypoxia, and to keep the head elevated to maximize the functional residual capacity (FRC), which is the reservoir of oxygen in the patient’s lungs.
  3. “LIMIT ATTEMPTS, Consider calling for help” is new and printed within a red box in the INTUBATION ATTEMPT AFTER GENERAL ANESTHESIA –> FAILED pathway. This is an effort to prevent repetitive unsuccessful intubation attempts from soaking up precious time, during which the brain is poorly oxygenated.
  4. “LIMIT ATTEMPTS AND CONSIDER AWAKENING THE PATIENT” is new and printed in red in the NON-EMERGENCY PATHWAY under the “Ventilation adequate/intubation unsuccessful” pathway. This is again an effort prevent repetitive unsuccessful intubation attempts from soaking up precious time, during which the brain is poorly oxygenated.
  5. “LIMIT ATTEMPTS AND BE AWARE OF THE PASSAGE OF TIME, CALL FOR HELP/FOR INVASIVE ACCESS” is new and printed in red in the EMERGENCY PATHWAY under the MASK VENTILATION NOT ADEQUATE, SUPRAGLOTTIC AIRWAY NOT ADEQUATE pathway. This is again an effort to prevent repetitive unsuccessful intubation attempts from soaking up precious time, during which the brain is poorly oxygenated.

These changes, printed or boxed in red, emphasize that the pace of difficult airway decisions is important. The duration of elapsed time is vital. When an anesthesia provider cannot intubate the patient and then cannot ventilate the patient, the oxygen level in the blood can plummet. There is a significant danger of anoxic brain damage within minutes. I’ve previously reviewed this topic in a 2019 Anesthesia Grand Rounds Lecture at Stanford, summarized in my article “Five Minutes to Avoid Anoxic Brain Damage.” The U.S. Library of Medicine website states that “Brain cells are very sensitive to a lack of oxygen. Some brain cells start dying less than 5 minutes after their oxygen supply disappears. As a result, brain hypoxia can rapidly cause severe brain damage or death,” and “Time is very important when an unconscious person is not breathing. Permanent brain damage begins after only 4 minutes without oxygen, and death can occur as soon as 4 to 6 minutes later.”

The sentence “Be aware of the passage of time, the number of attempts, and oxygen saturation” appears more than once in the 2022 Difficult Airway Algorithm Guidelines article, and is a key point for all anesthesia providers who encounter a difficulty airway emergency.

In my roles as an anesthesia quality assurance reviewer or a medical-legal expert consultant, I’ve seen this issue arise multiple times. Even though anesthesia providers believe they are following the Difficult Algorithm accurately, they are doing things too slowly, and they waste too much time. Once it’s clear that a “Cannot intubate-cannot oxygenate” scenario is occurring, the time clock is running, and the anesthesia provider must not only do the correct thing but he or she must do the correct thing without undue delay. The necessary procedure may be as invasive as a cricothyroidotomy/front of the neck access via the scalpel-bougie-endotracheal tube approach.  

The five points listed above are the major changes in the algorithm. In addition, the new 2022 article includes a Pediatric Difficult Airway Algorithm and an approach to Extubation of the Trachea in a Difficult Airway Patient. Other important quotes from the 2022 article include (bold emphasis added):

  1. “The consultants and members of participating organizations strongly agree with recommendations to perform awake intubation, when appropriate, if the patient is suspected to be a difficult intubation and difficult ventilation (face mask/supraglottic airway) is anticipated.”
  2. “Meta-analyses of randomized controlled trials comparing video-assisted laryngoscopy with direct laryngoscopy in patients with predicted difficult airways reported improved laryngeal views, a higher frequency of successful intubations, a higher frequency of first attempt intubations, and fewer intubation maneuvers with video-assisted laryngoscopy.”
  3. The footnote (7) for alternative difficult intubation approaches states: 7Alternative difficult intubation approaches include but are not limited to video-assisted laryngoscopy, alternative laryngoscope blades, combined techniques, intubating supraglottic airway (with or without flexible bronchoscopic guidance), flexible bronchoscopy, introducer, and lighted stylet or lightwand. 
  4. “A randomized controlled trial comparing a videolaryngoscope combined with a flexible bronchoscope reported a greater first attempt success rate with the combination technique than with a videolaryngoscope alone.”
  5. “When appropriate, refer to an algorithm and/or cognitive aid.” 

AUTHOR’S NOTE: I’d suggest that the Stanford Emergency Manual of cognitive aid algorithms for anesthesia and ACLS emergencies be onsite at all anesthetizing locations. 

I’d also recommend that the 2022 ASA Difficult Airway guideline algorithm be onsite at all anesthetizing locations.

Every anesthesia professional will encounter patients with difficult airways—this is one of the most important and most feared situations in our specialty. Commit the 2022 ASA Difficult Airway Algorithm to memory. Use awake intubation when you’re concerned about the potential of a “Cannot intubate-cannot oxygenate” scenario. And if you’re in the middle of a difficult airway emergency, call for help and be aware of the passage of time, the number of attempts, and the oxygen saturation. Don’t let an excessive number of minutes elapse without regaining oxygenation of your patient.

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The most popular posts for laypeople on The Anesthesia Consultant include:
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READ ABOUT RICK NOVAK’S FICTION WRITING AT RICK NOVAK.COM.

A MORBIDLY OBESE PATIENT WITH MEAT STUCK IN HIS ESOPHAGUS

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THE ANESTHESIA CONSULTANT
THE ANESTHESIA CONSULTANT
Physician anesthesiologist at Stanford at Associated Anesthesiologists Medical Group
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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You’re the anesthesiologist on call on a Saturday night. A patient arrives at the Emergency Room complaining that he ate piece of steak one hour ago, and the meat got stuck in his throat. He is morbidly obese patient who stands six feet tall and weighs 350 pounds, for a BMI of 47.

The attending general surgeon wants to do an upper GI endoscopy to extract the piece of meat from the patient’s esophagus or push it through into the stomach. He’s called on you to do the anesthetic. 

What do you do?

You examine the patient and find he has a short neck, a small mouth, and a large tongue. You cannot see his soft palate at all, and you rate him as a Mallampati 4.

Mallampati Class IV airway

The patient is alert, and is an excellent historian. He cannot even swallow his saliva. He has no difficulty breathing or significant chest pain. His hospital chart shows no past anesthetics, and he has no medical problems except hypertension which is treated with lisinopril. His vital signs are normal, and his oxygen saturation is 96% on room air.You are six months out of anesthesia training and new to this hospital. The surgeon—a 60-year-old male with the brash confidence of General Patton—is an iconic and respected figure at this medical center. He wants to proceed at once. It’s 8 pm on a Saturday night. He requests “just a little sedation” so he can insert the endoscope past the gag reflex and into the esophagus.

You bring the patient into the endoscopy suite, attach the standard vital signs monitors, and administer oxygen via a Procedural Oxygen Mask (POM, made by Mercury Medical).

You administer 2 mg of Versed and 100 micrograms of fentanyl IV. The surgeon sprays Cetacaine into the patient’s mouth for topical anesthesia and inserts a bite block. After five minutes time the patient is still wide awake. The surgeon looks at you and says, “I need him a little deeper than this.” You administer another 1 mg of Versed and 50 micrograms of fentanyl. After another five minutes time, the patient is still wide awake. The surgeon looks at you and repeats, “I need him a little deeper than this.” He says this in an impatient condescending tone, and you feel pressured. You administer 50 mg of propofol, and the patient’s eyes begin to drift closed. The surgeon inserts the gastroscope, after which the patient coughs, gags, and vomits into his airway. His oxygen saturation which had been 100% quickly plummets to 75%. You move to the head of the bed, suction the patient’s mouth, and attempt bag-mask ventilation without success. His oxygen saturation drops to 60%. You reach for a Miller 3 laryngoscope and attempt to intubate the trachea, but you cannot visualize his vocal cords. You are panicked. The surgeon is screaming at you to do something. You tell the surgeon he needs to do a tracheostomy. In the meantime you insert a laryngeal mask airway into the patient’s throat, but are still unable to ventilate the lungs. The ECG rhythm converts to ventricular fibrillation, and you call a Code Blue.

After thirty minutes of CPR and ACLS, the patient is declared dead.

What went wrong here? A patient who walked into the hospital is now dead. The basic problem was that the anesthesiologist proceeded to deeply sedate a patient with a full stomach (a known aspiration risk) without first controlling the airway by inserting an endotracheal tube. This morbidly obese patient with a thick neck, a small mouth, and a large tongue was always going to be difficult to intubate, but a successful intubation was most likely to occur under controlled circumstances with the patient awake prior to any endoscopy. The issue of a domineering surgeon pushing an inexperienced anesthesia provider into doing the wrong anesthetic is a key problem. This can and does happen, and once the case has concluded with a bad outcome, that same surgeon will deny any culpability, step back and say “I don’t do anesthesia. The decisions and actions of the anesthesiologist caused the problem, not me.”

How should the anesthetic have been done? 

In a parallel universe, an experienced anesthesiologist would do the following:

  • Explain to the surgeon and the patient that the meat stuck in the esophagus presents a dire risk of aspiration into the lungs and loss of airway, and explain to them that the case must be done either entirely awake without sedation (unlikely to be successful), or as a general anesthetic with an endotracheal tube placed prior to any endoscopy intervention.
  • This case is best done in an operating room, rather than in an endoscopy suite.
  • The anesthesiologist will assemble all emergency airway equipment, including a Glidescope, a fiberoptic laryngoscope, the entire difficult airway cart, and the scalpel, bougie, tube equipment for an emergency cricothyrotomy. 
  • The anesthesiologist will likely call in a second pair of experienced hands, either a second anesthesiologist or perhaps the in-house emergency room physician most experienced with intubating patients.
  • A rapid sequence intubation with propofol, succinylcholine, and cricoid pressure is a possible approach, but runs the risk that if the airway is so difficult that the endotracheal tube cannot be passed on the first attempt, the patient will be difficult to ventilate, difficult to oxygenate, and the meat and saliva from the esophagus could aspirate into the airway, leading to a hypoxic emergency.
  • A safer approach is an awake oral intubation using a fiberoptic laryngoscope. The back of the operating room table is inclined upward into a sitting position. Topical anesthesia and local nerve blocks of the airway are performed. See the footnote below (referenced from Miller’s Anesthesia) for a detailed description of the airway anesthesia.A Moderate sedation with Versed and fentanyl is administered, but the patient is kept awake. There’s still a risk that the topical anesthesia will blunt the cough reflex if the patient regurgitates the meat, so suction and a MaGill forceps are immediately available.
  • The anesthesiologist inserts the fiberoptic scope through an endotracheal tube (ET tube) and advances the scope into the mouth until he or she is able to visualize the vocal cords. This can be difficult and may take time, but there is no acute emergency, so an unhurried approach is warranted. Once the fiberoptic scope is threaded through the vocal cords, the patient will most likely cough violently and will require some restraint by two individuals, one on each side of the bed. The ET tube is threaded over the scope quickly and the balloon on the ET tube is inflated. The tube is connected to the anesthesia machine circuit and end-tidal CO2 is confirmed. At this point an IV bolus of propofol and rocuronium is administered to induce general anesthesia. 
  • Once the ET tube is taped securely in place, the surgeon can position the patient as he desires for the upper GI endoscopy. Anesthesia is maintained with sevoflurane and oxygen. When the surgeon is finished, the patient is awakened using sugammadex as necessary to reverse the muscle relaxation. When the patient opens his eyes, he can be safely extubated.

What are the lessons to be learned from this case study?

  • Don’t be intimidated or pushed into an unsafe anesthesia plan. Do what you were trained to do in residency, and stick to safe anesthesia practice. If an adverse outcome occurs, claiming the surgeon made you do something unsafe will not help you one bit. You are in charge of all anesthesia decisions.
  • In anesthesia practice and all acute medicine care, you must manage Airway-Breathing-Circulation (A-B-C) in that order. Anesthesiologists are trained as airway experts, and for this reason we are the most vital acute care physicians in a medical emergency. The airway must managed first.
  • Take great care when anesthetizing a morbidly obese patient. They are at higher risk for anesthetic complications. They are also at greater risk for surgical and perioperative medical problems. See the lay press coverage in U.S. News and World Report, and also another post from this blog.
  • Maintain your skills in awake intubation. No anesthesiologist uses awake intubation often. For nearly every patient the appropriate sequence is to induce anesthesia first and intubate the trachea afterwards. But some patients: e.g. those with ankylosing spondylitis, congenital airway deformities like Treacher Collins syndrome, or certain patients with morbidly obesity or super morbidly obesity (BMI > 50), awake intubation is indicated. One of my professional partners, a former Senior Examiner for the American Board of Anesthesiologists, told me that during national anesthesia oral board examinations, when a patient presented with severe airway abnormalities for a surgical case, it was very common for successful examinees to state they would perform an awake intubation. Why? Because an awake intubation burns no bridges. The patient is unharmed by general anesthesia until the ET tube is already in place, and thus is unlikely to have a Cannot Intubate-Cannot Ventilate situation that can lead to life-threatening hypoxia. And as well, in an oral exam the examinee doesn’t have to actually perform the procedure—they only have to state they could do it successfully.
  • How do you maintain your skill in awake intubation? This is the tough question. When I was in residency training, Dr. Phil Larson, a former Chairman of Anesthesia at Stanford and former Editor-in-Chief of the journal Anesthesiology, taught us elective awake intubation on patients with normal airways, who did not require an awake intubation, so we could hone the skill. Each patient was sedated with IV narcotics. Local lidocaine nerve blocks were done, and an injection of local anesthetic was administered through the cricothyroid membrane, all prior to us performing the awake fiberoptic intubation successfully. Did this take extra time? It did. The intubation and anesthesia induction took ten minutes instead of one minute. Did the surgeons mind? They didn’t, because they respected Dr. Larson, they were glad an excellent anesthesiologist was attending to their cases, and they realized that nine minutes of time was no big deal. Am I recommending you do this in your practice? No, but in this age of the Glidescope, many anesthesiologists have forgotten how to utilize a fiberoptic intubation. I recommend you practice fiberoptic intubation on asleep patients, and maintain the skill.

You may need it to save someone’s life one day.

Footnote:

A. (From Chapter 44, Airway Management in Adults, Miller’s Anesthesia, Ninth edition, pp 1373-1412)  “Topical application of local anesthetic to the airway should, in most cases, be the primary anesthetic for awake airway management. Lidocaine is the most commonly used local anesthetic for awake airway management because of its rapid onset, high therapeutic index, and availability in a wide variety of preparations and concentrations. Benzocaine and Cetacaine (a topical application spray containing benzocaine, tetracaine, and butamben; Cetylite Industries, Pennsauken, NJ) provide excellent topical anesthesia of the airway, but their use is limited by the risk of methemoglobinemia, which can occur with as little as 1 to 2 seconds of spraying. . . .  A mixture of lidocaine 3% and phenylephrine 0.25%, which can be made by combining lidocaine 4% and phenylephrine 1% in a 3:1 ratio, has similar anesthetic and vasoconstrictive properties as topical cocaine and can be used as a substitute. Topical application of local anesthetic should primarily be focused on the base of the tongue (pressure receptors here act as the afferent component of the gag reflex), the oropharynx, the hypopharynx, and the laryngeal structures; anesthesia of the oral cavity is unnecessary. . . . Before topical application of local anesthetic to the airway, administration of an anticholinergic agent should be considered to aid in the drying of secretions, which helps improve both the effectiveness of the topical local anesthetic and visualization during laryngoscopy. Glycopyrrolate is usually preferred because it has less vagolytic effects than atropine at doses that inhibit secretions and does not cross the blood-brain barrier. It should be administered as early as possible to maximize its effectiveness. “. . . Oropharyngeal anesthesia can be achieved by the direct application of local anesthetic or by the use of an atomizer or nebulizer. Topical application of local anesthetic to the larynx can be achieved by directed atomization of a local anesthetic or by the  spray-as-you-go (SAYGO) method, which involves intermittently injecting local anesthetic through the suction port or working channel of a flexible intubation scope (FIS) or optical stylet, as it is advanced toward the trachea.“Topical application of local anesthetic to the airway mucosa using one or more of these methods is often sufficient. If supplemental anesthesia is required, then a variety of nerve blocks may be used. Three of the most useful are the glossopharyngeal nerve block, superior laryngeal nerve block, and translaryngeal block. The glossopharyngeal nerve supplies sensory innervation to the posterior third of the tongue, vallecula, the anterior surface of the epiglottis, and the posterior and lateral walls of the pharynx, and is the afferent pathway of the gag reflex. To block this nerve, the tongue is displaced medially, forming a gutter (glossogingival groove). A 25-gauge spinal needle is inserted at the base of the anterior tonsillar pillar, just lateral to the base of the tongue, to a depth of 0.5 cm. After negative aspiration for blood or air, 2 mL of 2% lidocaine is injected. The process is then repeated on the contralateral side. The same procedure can be performed noninvasively with cotton-tipped swabs soaked in 4% lidocaine; the swabs are held in place for 5 minutes.”     

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popular posts for laypeople on The Anesthesia Consultant include:
How Long Will It Take To Wake Up From General Anesthesia?
Why Did Take Me So Long To Wake From General Anesthesia?
Will I Have a Breathing Tube During Anesthesia?
What Are the Common Anesthesia Medications?
How Safe is Anesthesia in the 21st Century?
Will I Be Nauseated After General Anesthesia?
What Are the Anesthesia Risks For Children?

The most popular posts for anesthesia professionals on The Anesthesia Consultant  include:
10 Trends for the Future of Anesthesia
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Should You Cancel Surgery For a Blood Pressure = 170/99?
Advice For Passing the Anesthesia Oral Board Exams
What Personal Characteristics are Necessary to Become a Successful Anesthesiologist?

READ ABOUT RICK NOVAK’S FICTION WRITING AT RICK NOVAK.COM.

AVOIDING AIRWAY DISASTERS IN ANESTHESIA

THE ANESTHESIA CONSULTANT 8 Comments
THE ANESTHESIA CONSULTANT
THE ANESTHESIA CONSULTANT
Physician anesthesiologist at Stanford at Associated Anesthesiologists Medical Group
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
THE ANESTHESIA CONSULTANT
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Every anesthesia practitioner dreads airway disasters.  Anesthesiologists and nurse anesthetists are airway experts, but anesthesia professionals are often the only person in the operating room capable of keeping a patient alive if the patient’s airway is occluded or lost. Hypoxia from an airway disaster can lead to brain damage within minutes, so there is little time for human error.

A fundamental skill is the ability to assess a patient’s airway prior to anesthesia. One must assess whether the patient will pose: 1) difficult bag-mask ventilation, 2) difficult supraglottic/laryngeal mask airway placement, 3) difficult laryngoscopy, 4) difficult endotracheal intubation, or 5) difficult surgical airway.

Of critical importance is #1) above, that is, recognizing the patient who will present difficult mask ventilation. Conditions that make for difficult bag-mask ventilation are uncommon, and usually can be detected during physical examination. Despite the importance of expertise in endotracheal intubation, I teach residents and trainees that the most important airway skill is bag-mask ventilation. Every year I encounter several patients who present unanticipated difficult intubations. In each of these patients, I’m able to mask ventilate the patient to keep them oxygenated while I try various strategies and techniques to successfully place an endotracheal tube or a laryngeal mask airway.

Most anesthesia airway disasters aren’t merely difficult intubations, but scenarios that are classified as “can’t intubate, can’t ventilate.” In these “can’t intubate, can’t ventilate” situations, the anesthesiology professional has only minutes to restore oxygenation to the patient or else the risk of permanent brain damage is very real.

The American Society of Anesthesiologists Difficult Airway Algorithm is a guide for anesthesia practitioners regarding how proceed in airway management. The algorithm is detailed, complex, comprehensive, and defines the standard of care in any medical-legal battle concerning hypoxic brain damage due difficult airway clinical cases. The algorithm is so detailed, complex, and comprehensive that some would say it’s impossible to remember every step in the acute occurrence of an airway disaster.

A simplified approach has been touted.

Dr. C. Philip Larson, Professor Emeritus, Anesthesia and Neurosurgery, Stanford University, and Professor of Clinical Anesthesiology at UCLA, and previous Chairman of Anesthesiology at Stanford, was one of my teachers and mentors for both endotracheal intubation and fiberoptic intubation. In a Letter to the Editor of the Stanford Gas Pipeline in May, 2013, Dr. Larson wrote, “there is no scientific evidence that anesthesia is safer because of the ASA Difficult Airway Algorithm.  While an interesting educational document, I question the daily clinical value of this algorithm, even in its most recent form (Anesthesiology 2013; 118:251-70). The ASA Difficult Airway Algorithm was developed by committee and has all the problems that result when done that way.  It is complex, diffuse, multi-dimensional, and all-encompassing such that it is not an instrument that one can easily adopt and practice in the clinical setting.”

Dr. Larson recommends a system of Plans A-D, a system he published in Clinical Anesthesiology, editors Morgan GE, Mikhail MS, Murray MJ, Lange Medical publication, 4th edition, 2006, pp 104-5, and in Current Reviews in Clinical Anesthesiology (2009; 30:61-72), and also in the Appendix on airway management and intubation in the newest edition of Anesthesiologists Manual of Surgical Procedures by Richard Jaffe et al (Lippincott Williams and Wilkins, 5th Edition, May 2014). An outline of the system is as follows:

A.  Plan A is direct laryngoscopy an intubation using a Miller or MacIntosh blade.

B.  If Plan A is unsuccessful, Plan B includes use of video laryngoscopy with a GlideScope or similar device.

C.  If Plan B is unsuccessful, Plan C is placement of an LMA with intubation through that LMA using a fiberoptic bronchoscope.

D.  “If Plans A-C fail,” Larson wrote in his Letter to the Editor of the Stanford Gas Pipeline in May, 2013, “one needs Plan D.  The first and perhaps the most prudent option is to cancel the proposed operation, terminate the anesthetic, and wake the patient up. The operation would be rescheduled for another day, and at that time an awake fiberoptic intubation technique would be used.  Alternatively, if the operation cannot be postponed, then the surgeon should be informed that a surgical airway (i.e.: tracheostomy) must be performed before the planned operation can commence.  To date, utilization of Plan D because of failure of Plans A-C has not occurred.”

Dr. Larson wrote that the airway skills in Plan A – C should be practiced regularly on patients with normal airways. I agree with Dr. Larson that in managing difficult airways, a practitioner needs a short list of procedural skills that he or she is expert at rather that a large array of procedures that they rarely use (such as the alternative intubation techniques using light wands or blind nasal techniques, or invasive airway procedures such as retrograde wires passed through the cricothyroid membrane or transtracheal jet ventilation through a catheter). It’s wise for anesthesiologists to regularly hone their techniques of video laryngoscopy (Plan B) and fiberoptic intubation via an LMA (Plan C) on patients with normal airways, to remain expert with these skills.

Regarding Plan B, an important advance is the availability of portable, disposable video laryngoscopes such as the Airtraq, a guided video intubation device. In my career I sometimes work in solo operating room suites distant from hospitals. In these settings, the operating room is usually not be stocked with an expensive video scope such as the GlideScope, the C-MAC, or the McGrath 5. I carry an Airtraq in my briefcase, and if the need for Plan B arises I am prepared to utilize video laryngoscopy at any anesthetizing location. I suggest the practice of carrying an Airtraq to any anesthesiologist who gives general anesthetics in remote locations.

Regarding emergency surgical rescue airway management, Dr. Larson recently published a Letter to the Editor in the American Society of Anesthesiologists Newsletter, February 2014, entitled, Ditch the Needle – Teach the Knife. In this letter, Dr. Larson wrote:

“in life-threatening airway obstruction, … an emergency cricothyrotomy is much quicker, easier, safer and more effective than any needle-based technique. I can state with confidence that there is no place in emergency airway management for needle-based attempts to establish ventilation. It should be deleted from the ASA Difficult Airway Algorithm. I have participated in seven cricothyrotomies in emergency airway situations, and all of the patients left the hospital without any neurological injury or complications from the cricothyrotomy. The risk-benefit ratio is markedly in favor the knife technique…. With a knife, or scissors, one cuts quickly either vertically or horizontally below the thyroid cartilage and there is the cricothyroid membrane or tracheal rings. The knife is inserted into the trachea and turned 90 degrees, and an airway is established. At that point, a small tube of any type can be inserted next to the knife. The knife technique is much safer because there is virtually nothing that one can harm by making an incision within two inches or less in the midline of the neck, and it can be performed in less than 30 seconds. In contrast, the needle is fraught with complications, including identifying the trachea, making certain that the needle is entirely in the trachea and does not move ( to avoid subcutaneous emphysema when an oxygen source is established), establishing a pressurized oxygen delivery system (which will take more than five minutes even in the most experienced circumstances), and avoiding causing a tension pneumothorax… I know of multiple cases of acute airway obstruction where the needle technique was attempted, and in all cases the patients died. I know of no such cases when a cricothyrotomy was used as the primary treatment of acute airway obstruction.”

A final note on the awake intubation of patients with a difficult airway: In hindsight in any difficult airway case, one often wishes they had secured an endotracheal tube prior to the induction of general anesthesia. The difficult problem is deciding prior to a case which patient has such a difficult airway that the induction of general anesthesia should be delayed until after intubation. In anesthesia oral board examinations it may be wise to say you would perform an awake intubation on a difficult airway patient rather than risk the “can’t intubate, can’t ventilate” scenario the examiner is probably poised to skewer you with. In medical malpractice lawsuits, plaintiff expert witnesses in anesthesia airway disaster cases often testify that a brain-dead patient’s life would have been saved if only the anesthesiologist had performed awake intubation rather than inducing general anesthesia first and then losing the airway. The key question is: how does one decide which patient needs an awake intubation? As an anesthesia practitioner, if you performed awake intubations on one out of 50 cases because you were worried about a difficult airway, you would delay operating rooms and surgeons multiple times per year because of your caution. You will not be popular if you do this. In my clinical practice and in the practice of the excellent Stanford anesthesiologists I work with, the prevalence of awake intubation is very low. I estimate most anesthesiologists perform between zero and two awake intubations per year. The most common indications include patients with severe ankylosing spondylitis of the cervical spine, congenital airway anomalies, and severe morbid obesity. Dr. Larson wrote in his Letter to the Editor of the Stanford Gas Pipeline in May, 2013, “I do anesthesia for most of the patients with complex head and neck tumors, and I find fewer and fewer indications for awake fiberoptic intubation. As long as the lungs can be ventilated by bag-mask or LMA, which is true for almost all sedated patients, Plan C is easier, quicker and safer than awake fiberoptic intubation both for the patient and the anesthesia provider.  In experienced hands, Plan C can be completed in less than 5 minutes, and one can become proficient by practicing in normal patients. I have done hundreds of Plan C’s, many under difficult circumstances, without a single failure or complication.  Obviously, no technique will encompass every conceivable airway problem, but mastering Plans A-D and awake oral and nasal fiberoptic intubation will meet the needs of anesthesia providers in almost all circumstances.”

May you never experience the  emotional trauma of an airway disaster. Become an expert in bag-mask ventilation, always have access to a video laryngoscope or an Airtraq, and consider  Dr. Larson’s  Plan A-D system, described in detail in the Appendix on airway management and intubation in the newest edition of Anesthesiologists Manual of Surgical Procedures by Richard Jaffe et al (Lippincott Williams and Wilkins, 5th Edition, May 2014).

 

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Published in September 2017:  The second edition of THE DOCTOR AND MR. DYLAN, Dr. Novak’s debut novel, a medical-legal mystery which blends the science and practice of anesthesiology with unforgettable characters, a page-turning plot, and the legacy of Nobel Prize winner Bob Dylan.

KIRKUS REVIEW

In this debut thriller, tragedies strike an anesthesiologist as he tries to start a new life with his son.

Dr. Nico Antone, an anesthesiologist at Stanford University, is married to Alexandra, a high-powered real estate agent obsessed with money. Their son, Johnny, an 11th-grader with immense potential, struggles to get the grades he’ll need to attend an Ivy League college. After a screaming match with Alexandra, Nico moves himself and Johnny from Palo Alto, California, to his frozen childhood home of Hibbing, Minnesota. The move should help Johnny improve his grades and thus seem more attractive to universities, but Nico loves the freedom from his wife, too. Hibbing also happens to be the hometown of music icon Bob Dylan. Joining the hospital staff, Nico runs afoul of a grouchy nurse anesthetist calling himself Bobby Dylan, who plays Dylan songs twice a week in a bar called Heaven’s Door. As Nico and Johnny settle in, their lives turn around; they even start dating the gorgeous mother/daughter pair of Lena and Echo Johnson. However, when Johnny accidentally impregnates Echo, the lives of the Hibbing transplants start to implode. In true page-turner fashion, first-time novelist Novak gets started by killing soulless Alexandra, which accelerates the downfall of his underdog protagonist now accused of murder. Dialogue is pitch-perfect, and the insults hurled between Nico and his wife are as hilarious as they are hurtful: “Are you my husband, Nico? Or my dependent?” The author’s medical expertise proves central to the plot, and there are a few grisly moments, as when “dark blood percolated” from a patient’s nostrils “like coffee grounds.” Bob Dylan details add quirkiness to what might otherwise be a chilly revenge tale; we’re told, for instance, that Dylan taught “every singer with a less-than-perfect voice…how to sneer and twist off syllables.” Courtroom scenes toward the end crackle with energy, though one scene involving a snowmobile ties up a certain plot thread too neatly. By the end, Nico has rolled with a great many punches.

Nuanced characterization and crafty details help this debut soar.

Click on the image below to reach the Amazon link to The Doctor and Mr. Dylan:

41wlRoWITkL

Learn more about Rick Novak’s fiction writing at ricknovak.com by clicking on the picture below:  

DSC04882_edited

 

 

EMERGENCY AIRWAY BLEEDING AFTER SLEEP APNEA SURGERY

THE ANESTHESIA CONSULTANT 2 Comments
THE ANESTHESIA CONSULTANT
THE ANESTHESIA CONSULTANT
Physician anesthesiologist at Stanford at Associated Anesthesiologists Medical Group
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
THE ANESTHESIA CONSULTANT
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Clinical Case for Discussion:   You are called at 0200 hours  to anesthetize a 50-year-old man who is bleeding from his palate.  He is 14 hours status-post  a uvulopalatopharyngeoplasty (UPPP) for sleep apnea.  He is 6 feet tall, weighs 200 pounds, and  he is spitting up blood.  What do you do?

Discussion:   You meet the patient in the ICU.  He is sitting up in bed,  spitting out small amounts of blood and swallowing the rest.  He has been bleeding for four hours, and the total volume of blood seen has been less than a cup.   Vital signs are:  pulse 100, blood pressure 160/90, and oxygen saturation 97% on room air.  The airway exam reveals dried blood on the mouth and tongue, moderate edema of the  pharynx, tongue, and mucous membranes, and no bleeding point is seen.  Review of the chart reveals that your partner intubated the trachea with a Miller #2 blade without difficulty that morning for elective surgery. The surgeon wants the patient asleep as soon as possible.  You transport the patient to the operating room, and have him breath 100% oxygen through a mask while you prepare for the anesthetic.

The A-B-C’s of Airway-Breathing-Circulation dictate that the Airway is the most important factor to consider in this case.   You have the principles of the ASA Difficult Airway Algorithm (see http://www.ASAhq.org) committed to memory.  You plan a strategy for the airway management.  Per the Algorithm, you begin by assessing the likelihood of four basic problems:  1) Difficult ventilation, 2) Difficult intubation, 3) Difficulty with patient cooperation, and 4) Difficult tracheostomy.   You assess that you will be able to mask ventilate this patient, but there is some chance that the blood and edema will make intubation difficult.  You also consider that blood and edema could make both mask ventilation and intubation difficult.  Patient cooperation is adequate, and the surgeon states that he would not have difficulty doing a tracheostomy or cricothyroidotomy.

Next you consider the choices of:   a) awake intubation vs. inducing general anesthesia first, b) use of non-invasive techniques as the initial approach to intubation vs. surgical techniques like tracheostomy, and c) preservation of spontaneous ventilation during intubation attempts vs. ablation of spontaneous ventilation.

Your assessment is that awake fiber optic intubation would be difficult secondary to the active airway bleeding.  Blind awake nasal intubation is a possibility, but looking at the patient, you make a different choice.   You are confident that you can induce general anesthesia, use cricoid pressure, paralyze the patient, and intubate the trachea using a Miller #2 blade as your partner did the previous morning.  If you have difficulty seeing the larynx, you will use a Yankauer suction to clear blood, try alternate laryngoscope blades, and support oxygenation by mask ventilation while cricoid pressure is continued. You may utilize other options as necessary, including a bougie or a light wand.  If ventilation becomes difficult, you will insert an LMA.  If ventilation becomes impossible, the surgeon will perform an emergency surgical airway.

You need an assigned individual to assist you during your airway management.  Because there is no other anesthesiologist in the hospital, your otolaryngology colleague is the obvious assistant.   Before you induce anesthesia, you bring the difficult airway cart into the operating room, as well as a tracheostomy tray for the surgeon.

You discuss this plan with the surgeon.  After  preoxygenation, you induce anesthesia with propofol and succinylcholine.  Cricoid pressure is applied.  When you insert the  laryngoscope  into the mouth, all you see is blood, swollen tissues, and no view of the larynx.  Your next action is aggressive suctioning with a Yankauer catheter, and after repositioning the laryngoscope, you are able to see the larynx.  The tracheal tube is placed, the cuff is inflated, and its location confirmed by CO2 and auscultation.  You recheck vital signs, begin  maintenance anesthesia with sevoflurane, and the surgery begins.

I had a case of this type twice in the last 5 months.  Both cases were effective in raising the endogenous catecholamine level of this anesthesiologist.   Both were good exercises in planning airway management.  The most striking characteristic of each case was the amount of blood in the airway when I inserted the laryngoscope.  The Yankauer suction catheter was essential, and I recommend inserting it immediately after inserting the laryngoscope.

The literature documents the prevalence of bleeding after UPPP as 1.4% (Mickelson SA, Is Postoperative Intensive Care Monitoring Necessary After UPPP?, Otol Head Neck Surg 1998 Oct, 119(4) 352-6.)   The bleeding patient post-tonsillectomy is a similar presentation.  Miller (Anesthesia, 2000, p 2188) writes “The incidence of post-tonsillectomy bleeding that requires surgery is 0.3 to 0.6 %. . . The extent of blood loss may not be obvious and is usually underestimated. . . Most problems before induction of anesthesia for bleeding tonsil are caused by unsuspected hypovolemia, full stomach, and airway obstruction. . . At induction of anesthesia, an additional person should be available to provide good suctioning of blood.  A rapid-sequence induction of anesthesia with application of cricoid pressure and slight head-down positioning of the patient will protect the trachea and glottis from aspiration of blood.”

The ASA Difficult Airway Algorithm. . . learn it well, and be prepared to apply it in the middle of the night.  Your heart rate may be faster than the patient’s.

Introducing …,  THE DOCTOR AND MR. DYLAN, Dr. Novak’s debut novel. Publication date September 9, 2014 by Pegasus Books.

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Published in September 2017:  The second edition of THE DOCTOR AND MR. DYLAN, Dr. Novak’s debut novel, a medical-legal mystery which blends the science and practice of anesthesiology with unforgettable characters, a page-turning plot, and the legacy of Nobel Prize winner Bob Dylan.

KIRKUS REVIEW

In this debut thriller, tragedies strike an anesthesiologist as he tries to start a new life with his son.

Dr. Nico Antone, an anesthesiologist at Stanford University, is married to Alexandra, a high-powered real estate agent obsessed with money. Their son, Johnny, an 11th-grader with immense potential, struggles to get the grades he’ll need to attend an Ivy League college. After a screaming match with Alexandra, Nico moves himself and Johnny from Palo Alto, California, to his frozen childhood home of Hibbing, Minnesota. The move should help Johnny improve his grades and thus seem more attractive to universities, but Nico loves the freedom from his wife, too. Hibbing also happens to be the hometown of music icon Bob Dylan. Joining the hospital staff, Nico runs afoul of a grouchy nurse anesthetist calling himself Bobby Dylan, who plays Dylan songs twice a week in a bar called Heaven’s Door. As Nico and Johnny settle in, their lives turn around; they even start dating the gorgeous mother/daughter pair of Lena and Echo Johnson. However, when Johnny accidentally impregnates Echo, the lives of the Hibbing transplants start to implode. In true page-turner fashion, first-time novelist Novak gets started by killing soulless Alexandra, which accelerates the downfall of his underdog protagonist now accused of murder. Dialogue is pitch-perfect, and the insults hurled between Nico and his wife are as hilarious as they are hurtful: “Are you my husband, Nico? Or my dependent?” The author’s medical expertise proves central to the plot, and there are a few grisly moments, as when “dark blood percolated” from a patient’s nostrils “like coffee grounds.” Bob Dylan details add quirkiness to what might otherwise be a chilly revenge tale; we’re told, for instance, that Dylan taught “every singer with a less-than-perfect voice…how to sneer and twist off syllables.” Courtroom scenes toward the end crackle with energy, though one scene involving a snowmobile ties up a certain plot thread too neatly. By the end, Nico has rolled with a great many punches.

Nuanced characterization and crafty details help this debut soar.

Click on the image below to reach the Amazon link to The Doctor and Mr. Dylan:

41wlRoWITkL

Learn more about Rick Novak’s fiction writing at ricknovak.com by clicking on the picture below:  

DSC04882_edited