CPAP vs AutoCPAP for Treatment of Obstructive Sleep Apnea (OSA) in the Postoperative Setting

The purpose of this study is to determine if an Autoadjusting CPAP machine is better than the
regular CPAP machine in treatment of Obstructive Sleep Apnea in the postoperative setting.

Patients with known Obstructive Sleep Apnea who are on CPAP therapy at home and undergo an
elective surgery (meeting specified inclusion and exclusion criteria) will be randomized to
either using Autoadjusting CPAP vs their usual CPAP at their prescribed settings the night
after surgery. During that night, they will be monitored with full polysomnography in their
hospital bed.

Inclusion Criteria:

1. Known OSA patients well-controlled by CPAP (not hypoxemic i.e. Oxygen Saturation
(SaO2) ≥ 89% and post-treatment Apnea Hypopnea (AHI) <10) and compliant ( > 3 hours
per night) presenting for elective inpatient surgery to MetroHealth Medical Center

2. Elective extremity or lower abdominal surgery

3. Age >18 years

Exclusion Criteria:

1. Surgery that may cause hypoxemia from causes other than the effect on upper airway
patency e.g. any thoracic surgery, upper abdominal surgery, head and neck surgery.

2. Surgery on the upper-airway.

3. Any condition that may interfere with application of CPAP mask e.g. trauma, surgery on
the face, vomiting, naso-gastric intubation etc.

4. OSA treated with a device other than CPAP e.g. Bilevel positive pressure or V-Positive
Airway Pressure

5. OSA needing very high levels of CPAP i.e. > 16 cms to achieve adequate control

6. OSA or other underlying cardiopulmonary conditions that require supplemental oxygen

7. Patients with decompensated congestive heart failure or advanced Chronic Obstructive
Pulmonary Disease (COPD) (FEV1<35% of predicted)

8. Patients with neuromuscular impairment

9. Patients with central sleep apnea

10. Pregnant patients

11. Decisional impaired subjects who are not able to consent