ANESTHESIA PATIENT QUESTION: HOW DOES MY SLEEP APNEA AFFECT MY RISKS FOR SURGERY?

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

This week I filmed a 26-minute question and answer video for the American Sleep Apnea Association regarding the topic of sleep apnea and surgery. The video provides answers to individuals who have obstructive sleep apnea and are contemplating surgery and anesthesia. The link to this video is HERE.

Obstructive sleep apnea (OSA) is a common medical condition which affects 17% of males aged 50 to 70 years, and 9% of females in the same age group.    Patients with OSA frequently present for surgery, and all anesthesia professionals must be aware of the risks involved with anesthetizing OSA patient. This video takes the opposite viewpoint and is directed toward patients with OSA, with the goals that they may understand their risks during anesthesia and surgery, and they may understand a physician anesthesiologist’s role in providing state of the art medical care to them before, during, and after surgery.

To simplify your search for information within the lecture, the outline for the questions presented in the video is as follows:

I. PREOPOPERATIVE CARE:

Let’s talk about the diagnosed sleep apnea patient and pre-operative assessment for upcoming surgery: The diagnosis of OSA is based on the presence of symptoms, such as disturbed sleep, snoring, hypertension, and also the frequency of sleep-related respiratory events during a sleep study or home sleep apnea testing. OSA is characterized by “recurrent upper airway collapse during sleep that leads too reduced or complete cessation of airflow, despite ongoing breathing efforts.”

The severity of OSA is typically characterized by the apnea-hypopnea index (AHI). The AHI is the number of apneic and hypopneic episodes the patient has per hour of sleep. Hypopnea means abnormally slow or shallow breathing. Apnea means a period of no breathing. (See the question on sleep studies below.)

How/why is it important to talk to all doctors involved about all your preexisting health conditions?  And disclosure of meds?  The medical history is critical in the preoperative assessment of patients. For OSA patients, pertinent comorbidities include hypertension, obesity, heart disease, lung disease, and a list of prescription medications including sedatives or pain relievers. 

Preoperative sleep study results matter to the anesthesiologist. Most sleep centers use an AHI between 5 and 10 events per hour as a normal limit.

The OSA disease classifications are as follows: 

Mild Disease:  AHI of 5 to 15 events per hour 

Moderate Disease:  AHI of 15 to 30 events per hour 

Severe Disease:  AHI of greater than 30 events per hour 

STOP-BANG questionnaires. Many patients who present for surgery do not have a diagnosis of OSA, and most patients do not have a preoperative sleep study. A STOP-BANG questionnaire contains 8 questions, and the answers to these questions help us screen for probable OSA. A patient is at high risk for OSA if they answer 5 questions positively, and re at intermediate risk if they answer 3-4 questions positively. The 8 questions include the presence of preoperative:

SNORING

CHRONIC TIREDNESS

OBSERVED EPISODES OF STOPPED BREATHING DURING SLEEP 

HYPERTENSION

A BODY MASS INDEX (BMI) OF  > 35

AGE> 50

NECK CIRCUMFERENCE > 15¾  INCHES

MALE GENDER.

What about other treatments for apnea, oral appliance, maxillary distractors, implants, positional devices, etc….

II. INTRAOPERATVE CARE:

What’s happening now with COVID and surgeries, and CPAP (Continuous Positive Airway Pressure) units?

Risks of anesthesia and the OSA patient?  All anesthesia care follows the priorities of Airway-Breathing-Circulation, or A B C. Many patients with OSA are at an increased risk for complications during airway management. For the anesthesiologist, mask ventilation, direct laryngoscopy, endotracheal intubation, and fiberoptic visualization of the airway can be more difficult in patients with OSA. Patients with OSA are at increased operative risk during and after surgery.

Type of surgery: non-airway surgery vs. airway surgery to treat OSA. Many OSA patients present for non-airway procedures such as orthopedic surgeries, abdominal surgeries, or endoscopies and colonoscopies. Other OSA patients present for procedures designed to improve their sleep apnea. These procedures involve surgical modification of the upper airway. These airway surgery patients require a different set of intraoperative and postoperative standards and concerns for the anesthesiologist. Commonly performed airway procedures for OSA include uvulopalatopharyngoplasty (UPPP), uvulopalatal flap surgery, tonsillectomy and adenoidectomy, genioglossus advancement, and maxillomandibular advancement. My Stanford surgical colleagues Dr. Nelson Powell and Dr. Robert Riley began to develop new surgical procedures for OSA in the 1980s. Drs. Powell and Riley were educated both as MDs and as dentists, and believed that the tongue base, not previously identified as a potential area of obstruction, was partially responsible for failures of the UPPP procedure to cure OSA. They pioneered the procedure of maxillary (upper jaw) and mandibular (lower jaw) advancement to increase the diameter of the upper airway.

Are sleep apnea patients monitored differently?

Apnea is a breathing disorder.  Do the medicines you use effect apnea patients differently?

III. POSTOPERATIVE CARE:

Are sleep apnea patients monitored differently in the Post Anesthesia Care Unit?

Can apnea patients use their CPAP units during surgery/ in recovery?

If you cannot use your CPAP in recovery, how do medical professionals monitor my breathing?

Are OSA patients discharged home after surgery, or are they kept in the hospital?

The answers to these four questions are discussed, with the caveat that for surgery involving surgical modification of the upper airway, postoperative patients require a different set of intraoperative and postoperative standards and concerns for the anesthesiologist, often including postoperative hospitalization to monitor for potential acute airway complications.

*

*

*

The most 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
Should You Cancel Anesthesia for a Potassium Level of 3.6?
12 Important Things to Know as You Near the End of Your Anesthesia Training
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?

LEARN MORE ABOUT RICK NOVAK’S FICTION WRITING AT RICK NOVAK.COM.

This image has an empty alt attribute; its file name is Screen-Shot-2020-09-15-at-11.03.31-AM-788x1024.png
ç

EMERGENCY AIRWAY BLEEDING AFTER SLEEP APNEA SURGERY

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

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.

*
*
*
*

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