Sleep Apnea and Bariatric Surgery

Richard P. Millman, MDMedical Director

Sleep Disorders Center of Lifespan HospitalsVice Chairman and Professor of MedicineAlpert 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

78

232 Morbidly Obese Diabetics

154

Gastric Bypass Operation refused for personal or insurance reasons

22/78 (28%)/6.2 yrs14/154 (9%)/ 9 yrs

P<0.0003

Mortality

1%/yr 4.5%/yr

Nicolas V. Christou MD PhDMc Gill University 2004

n Mortality

Controls 1,035 6.17%

Bariatric Surgery

5,746 0.68%

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 ApneaAmong 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 OSA2. the presence of any sleep apnea3. 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