Consequences of Obstructive Sleep Apnea on Respiratory Function Following Weight-loss Surgery

Study Overview
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Brief Summary
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The investigators propose to compare two different treatments, continuous positive airway pressure (CPAP) versus breathing of atmospheric pressure, in subjects with obstructive sleep apnea (OSA)recovering from weight loss surgery in the post anesthesia care unit (PACU). WE hypothesize that subjects with OSA will have a higher Apnea-Hypopnea Index (AHI) with desaturation and the investigators expect that post-operative CPAP treatment in the PACU will significantly improve the AHI and therefore improve patient safety in the PACU. The investigators also hypothesize that subjects with OSA have a greater decrease in oxygen saturation in response to opioid administration by patient-controlled opioid analgesia (PCA).

Detailed Description
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Patients with morbid obesity have an approximately 60-80 percent incidence of OSA depending on the criteria used for making diagnosis, and they are suggested to be at increased risk to develop serious perioperative complications, especially during the postoperative period. Weight loss might be considered as an appropriate treatment of OSA but in turn it has recently been reported that OSA is an independent risk factor for development of perioperative complications, importantly oxygen desaturation, in patients undergoing weight loss surgery. It seems logical to evaluate if these patients would benefit from post-operative CPAP treatment in the PACU. The results of this multidisciplinary study will have an impact on PACU treatment of patients with OSA and will further optimize patient care at MGH.

Official Title
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Consequences of Obstructive Sleep Apnea on Respiratory Function Following Weight-loss Surgery: A Randomized Controlled Trial

Conditions
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Obstructive Sleep Apnea, Obesity

Intervention / Treatment
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* Procedure: CPAP followed by atmospheric pressure
* Procedure: Atmospheric pressure followed by CPAP


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients scheduled for weight loss surgery at Massachusetts General Hospital Male and female subjects age ≥ 18 years Exclusion Criteria: CNS disease with impairment of cognitive function and/or muscle paresis such as stroke, or dementia age < 18 years missing or insufficient PSG data to make diagnosis OSA impaired decision making capacity

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Randomization Group 1<br>CPAP first followed by standard of care | Procedure: CPAP followed by atmospheric pressure<br>* In the PACU, Patients receive 2 hours of continuous-positive-airway-pressure (CPAP) oxygen at 30% FiO2 treatment followed by 2 hours of oxygen treatment (6 L O2/min) that is part of standard of care at Massachusetts General Hospital<br>* Other names: Tx Plan 1;|
| Active Comparator: Randomization group 2<br>Standard of care followed by CPAP | Procedure: Atmospheric pressure followed by CPAP<br>* In the PACU, patients receive 2 hours of Oxygen treatment (6L/min) that is part of standard-of-care at Massachusetts General Hospital, followed by 2 hours of Continuous Positive Airway Pressure (CPAP) treatment at 30% FiO2.<br>* Other names: Tx Plan 2;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| apnea hypopnea index (AHI) | The AHI is assessed for one night's sleep in the initial at-home sleep study conducted with a portable Alice monitor. Subsequently, the AHI is assessed during the patient's stay in the post-anesthesia-care unit (PACU) during which time they receive CPAP and oxygen treatment. | preoperatively for one night of sleep and during 2 hours of recovery room stay | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| apneas after opioid bolus self-administration | We are assessing the effects of OSA on apneas occurring in a 5 minute time-frame after opioid bolus self administration in the PACU, and consider these as related to opioid administration | 5 minutes after each opioid PCA administration | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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obstructive sleep apnea, obesity, respiratory function, weight loss surgery