Last week, I gave a lecture to our residents about the risks of medical complications after surgery in patients with obstructive sleep apnea.  It brought back memories of some studies about the risks of surgery in which I was involved and highlighted two recent studies of the risks of surgery published last month in journals from the field of anesthesiology.  There are a number of small studies out there about medical complications, but many of them focus on trivial issues like a 5-second drop in the oxygen level to 85% while someone is in the recovery room immediately after surgery.  That is not really relevant to anyone, so I prefer to focus on complications that have potential health implications, from as relatively minor as having the patient remain intubated (leaving in the breathing tube during placed during surgery for another day, for example) to more-substantial (pneumonia or emergency need for placement of a breathing tube).  I will describe findings that have been shown in two groups of patients with potential risks: those undergoing surgery for sleep apnea and those who have sleep apnea but are undergoing surgery unrelated to sleep apnea.

Risks for sleep apnea surgery 

About 10 years ago, I had the chance to work with Edward Weaver, MD, MPH at the University of Washington to determine the risks of complications in patients undergoing sleep apnea surgery.  Relying on a database on serious surgical complications in the Veterans Administration health care system, we were able to analyze data on 3130 patients who had sleep apnea surgery (mainly soft palate surgery) at over 100 hospitals from 1991-2001.   We showed that the risk of serious complication after sleep apnea surgery was 1.6% and the mortality risk was 0.2%, both of which were lower than many smaller studies suggested.  The most likely complications were related to breathing, ranging from being as minor as  We then followed this up with a second study that showed, perhaps not surprisingly, that the most important risk factor for complication was having serious medical conditions prior to surgery; this is true for almost any surgery.  Other risk factors were having worse sleep apnea (higher apnea-hypopnea index) and higher body mass index (a ratio of a person’s weight to their height).  In addition to being the largest study of its kind, the important thing is that the results were generalizable, meaning that they reflected the broad experience of patients because they came from many surgeons performing surgery at hospitals across the entire country.  Of course, the data came only from patients who had surgery in Veterans Administration medical centers, but the results overall were probably more realistic than from studies that are limited to individual surgeons or individual hospitals.

Risks of other surgeries in sleep apnea patients

Patients with sleep apnea who are undergoing surgery are at increased risk of complication if they are not treating their sleep apnea.  The best initial study showing this came from the Mayo Clinic, examining the risk of complication after knee or hip arthroplasty (joint replacement).  Interestingly, they started with 101 patients who underwent knee or hip replacement within 3 years before or after a diagnosis of sleep apnea and showed that the risks of complications were higher than in similar patients who did not have sleep apnea.  They then looked at patients who had sleep apnea diagnosed before the surgery, who received CPAP, and who were actually wearing their CPAP.  They showed that wearing CPAP prior to surgery reduced the risks of complication to the same level as in patients who did not have sleep apnea at all.

Society of Anesthesia and Sleep Medicine

In November, I was alerted to two new studies about risks of hip and knee replacement in sleep apnea patients by a newsletter from the Society of Anesthesia and Sleep Medicine.  This group was formed to advance the understanding of problems common to anesthesiology and sleep medicine, and these risks certainly fit in that category.  As a surgeon and sleep specialist, I am drawn to these concerns and have joined the SASM.  Professor David Hillman, an anesthesiologist and sleep specialist with whom I collaborate in research, encouraged me to join, and I now serve on its Clinical Committee.  SASM generates their own monthly Literature Updates and Featured Articles, which identified these two studies.  The first used high-quality databases from hospitals across the entire United States to show that patients with sleep apnea had a greater odds of serious complication (both pulmonary and cardiac) after knee or hip arthroplasty, in addition to having higher costs.  The second came from Manitoba and showed that sleep apnea was associated with serious complication, although treatment with CPAP (they could not determine whether patients were using it) did lower the risk.

There have been a number of other studies that have explored the risks of other surgeries in sleep apnea patients, and the research overall has shown similar findings.  This has led to the development of screening questionnaires that can be used in all patients scheduled for surgery in order to determine the risks of sleep apnea and, if needed, to proceed with testing and treatment before surgery.  The Society for Anesthesia and Sleep Medicine is one of a few groups dedicated to improving patient safety, and I have been excited to be a part of their efforts.  The SASM website has more information about the unique challenges of anesthesia in patients with sleep apnea, and I encourage anyone interested to explore it.


header logo - Reducing the risks of surgery in patients with obstructive sleep apnea


0 thoughts on “Reducing the risks of surgery in patients with obstructive sleep apnea

  • andrew sliwkowski says:

    Dr. Kezirian,
    Hope you find it o value my personal experience with MMA surgery(6/2013 @ age 44) with having both Obstructive and Central Sleep apnea:
    – Because of my central apnea it took an hour to stabilize my 02 levels (80-85%) before starting surgery. (11 hours total)
    – After surgery placed in intensive care because my 02 levels (80-85%) during wake time and worse if I could sleep. (felt like I just been a carcrash to my face and then placed on mount Everest )
    – Had to take morphine drip because could not swallow anything.
    – Morphine did not help O2 levels or respitory drive. Added 02.
    – After 4 days in hospital being awake the whole time.(could not sleep) went home.

    — 1ST night home could not sleep because of the pain… Taking oxytocin decrease my drive to breath and using portable 02 monitor had a waking o2 level of 85%.

    – 2nd night – could not sleep because of the pain – stuck my face in bucket of ice for pain relief but after 5 days of not sleep I realized I’d easily that I could easily fall asleep and probably drown.

    – 3rd night: – same as above

    – 4th night: – got 30 minutes of sleep by using my existing CPAP and powerful fan.
    woke-up and called 911 for ambulance because my 02 levels were 80-85. At the hospital o2 levels were stabilized with O2 and given anti-anxiety pill that dissolved on tongue 🙂 .

    -5th Day: Waking 02 levels between 85-90 made it hard to move or walk. Called Sleep Doctor for OK to take Diamox. After Diamox O2 LEVELS went to 90-95% 🙂

    — There is lot of events in the story and be happy to share if valuable to you, I hope you share with others at least 2 observations: For patients with central apnea there an additional set of concerns that need to be communicated to all members of surgical /sleep /Rx staff, pain of surgery and pain medications for it be MMA or hip surgery is likely to cause lower levels of sleep quality for an extended period of time and the use of ESS is valuable measurement tool in the recovery process.
    [Back Story]
    – Since age 15 (45 now) lived with excessive day time sleepiness (Epiworth Scale > 20)
    and managed it with Rx (Severe back injury and sleep fragmentation caused by the pain)

    – At age 35 formally diagnosed(sleep study) with Obstructive Sleep Apnea in 2005 and treated with CPAP and Rx (and blue light therapy)

    – At age 40 added custom dental retainer(pull jaw forward) to CPAP and Rx

    – At age 42 formally diagnosed with Central Sleep Apnea and Obstructive Sleep Apnea and treated with Non-Vented/CO2 CPAP + Dental + Rx. (tried Diamox)

    – At age 43, enrolled in 6 month sleep quality test using their device from sleepimage to measure, breakdown (NREM,REM, Obstructive vs Central…) and sleep quality nightly. After averaging less then 1.0 (where scale is 0 -4 where 0 is no sleep 4 is excellent) we decided that MMA surgery would manage the Obstructive and we could focus on the Central.

  • I have significant problems post shoulder surgery and would appreciate any help. I have severe sleep apnoea and am hypothyroid. I woke up after surgery on oxygen and feeling great.10 hours later after surgery I went back to sleep. Oxygen level was 91-94% with cpap prior to sleeping. Once asleep I had hot flashes like a fireball going from my head to chest. felt ill. When I woke 2 hours later I had eyesight and other problems. I have been left with stroke like symptoms but CT scan and MRI show nothing. Arteries fine.
    • My entire body felt very stiff for about 5 days after surgery but this resolved.
    • 4 days after surgery I developed hand tremors lasted about 5 hrs but I was too ill to care.
    10 months later :
    • Very tired sleeping for up to 18 hours a day.
    • Bowel problems
    • Temperature regulation I frequently feel hot but only upper torso and head
    • Headaches- always present, unrelenting in multiple areas in my head. I get paraesthesia although facial paraesthesia is not too bad. My headaches are not made worse by noise. The worse headaches are usually associated with the Tinnitus
    • Ears- Tinnitus started out just as a minor annoyance a feeling of fullness in the ears, a light hum. A sort of headachy feeling. Over the following week post surgery it progressed unpleasantly. It never stops- a hum low level buzz I can cope with. I am not sound sensitive –if the buzzing sound gets too loud I play music so I can only faintly hear it and this helps. I can’t drown out the really loud sound. Louder high pitched noises are very unpleasant and distracting. Another strange but minor symptom is my ears get itchy not on the outside but deep inside.
    • The sharp pain – a ice pick headache started soon after I was discharged. It happens about 5-7 x a day is unbelievably painful 10/10 and just when you think you can’t take it anymore it stops leaving a dull unpleasant ache. I think this only lasts a few seconds but feels like ages. Always both ears. Ears are frequently achy.
    • Hearing My hearing appears the same.
    • Eyes – my sight is more like a grainy old photo all the time frequently with cloudy areas, sometimes tiny lights. It’s never clear like it used to be. Most of the time I can read but only for shorter stretches. I used to read 4 hours a day –research papers , non-fiction books etc. My actual sight hasn’t changed . I don’t appear to be light sensitive in fact I had to increase the light on my computer as it seemed a bit dark
    • Memory- I don’t retain all of what I read .I sometimes have trouble retrieving words from my memory or use the wrong words
    • Taste –get a funny taste in my mouth not metal but similar-not a big deal but a change. Food tastes differently now.
    • Throat- it’s like there is pressure on the front of my neck, I have nearly choked a few times. In the hospital my voice was husky (I assumed from tubes down my throat) but this continued for about 5 months. Now I still have issues with swallowing unless I eat slowly and small amounts. Thyroid function and BP erractic since episode.
    • Thyroid changes- about 3-4 months after surgery I started to develop oedematous ankles, face and neck and sometimes wrists. This always occurs in the morning. Low level calcium present in blood related to parathyroid change.
    • all these symptoms were new.. The only treatment suggestion is to have a general anaesthetic and have electrodes placed under my scalp to try to desensitise the sensory symptoms.

    • Dr. Kezirian says:

      You are asking for medical advice, and honestly I cannot do this through a blog post comment. What stands out the most are your headaches, and I would recommend seeing a sleep medicine physician and a neurologist who specializes in headaches if you have not done so already.

Leave a Reply

2 + 7 =

This site uses Akismet to reduce spam. Learn how your comment data is processed.