Sleep Apnea and Bariatric Surgery Richard P. Millman, MD Medical Director Sleep Disorders Center of Lifespan Hospitals Vice Chairman and Professor of Medicine Alpert Medical School of Brown University

Disclosures Consultant Johnson and Johnson Development Corporation

LapBand Most widely used bariatric surgery world wide Received FDA approval in 2002 for US Expected weight loss 30 – 40 % of excess body weight in the first year and 50 – 55 % in 5 – 10 years

LapBand May be longer term issues with durability 15 year data shows some weight regain with 35% excess body weight loss maintained Band tightness needs constant monitoring and may need readjustment

Roux en Y gastric bypass Designed after observed weight loss in total gastrectomy patients Small proximal pouch Duodenum excluded 90 to150 cm Roux limb Can be done open or laparoscopically Excess body weight loss 60% at one year

Selection Criteria BMI > 35 with significant comorbidities BMI > 40 Failed conventional weight loss attempts

Selection Criteria Psychiatrically stable Women should not plan to be pregnant for 2 years Able to tolerate anesthesia

Comparative Risk to Medical Management Long term studies – patients eligible for surgery who don’t versus those who have surgery

Morbidly Obese Diabetics 154 Gastric Bypass Operation refused for personal or insurance reasons 22/78 (28%)/6.2 yrs14/154 (9%)/ 9 yrs P< Mortality 1%/yr4.5%/yr

Nicolas V. Christou MD PhD Mc Gill University 2004 nMortality Controls1, % Bariatric Surgery 5, % Reduction of relative risk of death by 89%

Longitudinal Assessment of Bariatric Surgery (LABS) NIH/NIDDK Consortium Six sites / 5 years Short term –operative risk, selection Long term – comorbidity control, behavioral issues, economics $15,000,000 direct

Comorbidities Raise Operative Risk Obstructive sleep apnea Diabetic vascular disease Reflux with reactive airway disease NASH with hepatomegaly

Why is Sleep Apnea an Issue? Anesthetic agents and narcotics can Increase pharyngeal muscle relaxation leading to airway collapse Depress respiratory drive

Mary and Bariatric Surgery 50 year old woman with known sleep apnea on PAP Underwent a Roux en Y procedure After leaving the PACU was sent to a regular surgery floor CPAP was not given since the surgeon felt that the pressure could blow out the sutures

The surgeon saw her a couple of hours later and increased the basal rate on her PCA morphine pump because she had 7/10 pain Later on she demonstrated increasing confusion but a blood gas was not checked She had an arrest and eventually died The family marched outside the hospital carrying signs stating “They Killed My Mother”

How could have this been prevented? Sending the patient to a stepdown unit with continuous monitoring of heart rate, respiratory rate and pulse oximetry Putting the patient on her PAP post operatively Avoidance of a continuous infusion of morphine

What if we do not know if they have sleep apnea? Sleep apnea is common in obese individuals What should we do about patients who haven’t been diagnosed with sleep apnea? Sleep studies are expensive and inconvenient. We certainly do not want to perform sleep studies in every patient going for weight loss surgery; do we?

Does this woman have sleep apnea?

Does this one?

Predicting Obstructive Sleep Apnea Among Women Candidates for Bariatric Surgery 296 consecutive women being evaluated for bariatric surgery who had undergone polysomnography Mean age 42 years (age 19-61) 86% had OSA (AHI = 5 or higher) 53 % had moderate to severe disease (AHI > 15) Sharkey et al JOURNAL OF WOMEN’S HEALTH 2010; 19: 1-9

Results Age, BMI, neck circumference, the presence of hypertension, observed apneas during sleep, and snoring all predicted to some degree AHI

The presence or absence of symptoms of snoring, observed apneas or daytime sleepiness did not correlate with: 1.the absence of OSA 2.the presence of any sleep apnea 3.the presence of moderate to severe OSA

Conclusions In other words we could not predict who had moderate to severe sleep apnea Everybody needed polysomnography

Is there anything special about sleep studies prior to bariatric surgery?

Yes You should make sure you study them on their back!

What about CPAP?

Who needs CPAP and how much? You have to decide ahead of time who needs a CPAP titration? Should it be an AHI of 5, 15, 30? When you do a titration in the sleep center study them on their back to mimic a post-op condition.

Possible Protocol Set the patient up on appropriate PAP settings for a month See them in followup and assess objectively and subjectively whether they are using PAP Make appropriate adjustments in therapy

The Day of Surgery Patient should bring PAP device to the hospital (or should bring in settings for a Respiratory Therapy unit) After leaving the PACU the patient should go to a stepdown unit with monitoring capabilities

The patient should be put on PAP Continuous basal rates of narcotics should be avoided if possible

Should the patient continue to use PAP at home? They definitely should if they had symptoms of OSA prior to the surgery or had severe OSA on polysomnography A repeat sleep study should be performed off PAP once stable weight loss has been obtained Pressures may need to be decreased as the patient is losing weight