CPAP in Patients With Severe Obesity After Anesthesia
The goal of this study is to compare two continuous positive airway pressure (CPAP) settings on heart and lung function in patients with severe obesity after anesthesia. The main questions it aims to answer are:

Does a recruitment maneuver and CPAP set to intrathoracic pressure (ITP) improve cardiopulmonary function compared to standard CPAP settings in patients with severe obesity after anesthesia?
Does the location of adipose tissue influence the response to CPAP settings in patients with severe obesity after anesthesia?

Participants will undergo monitoring of their intrathoracic pressure using an esophageal catheter. In the recovery area after anesthesia, participants will receive two CPAP settings, each for 20 minutes.

Intervention 1: Recruitment maneuver and CPAP will set to the level of intrathoracic pressure
Intervention 2: CPAP set to home settings (if OSA is present) or between 8-10 cmH20 (if OSA is not present).
- EligibilityCriteria: Inclusion Criteria:  Adult patients (≥ 18 years old) scheduled for elective non-cardiothoracic surgery requiring general anesthesia with an endotracheal tube Planned admission to the post-anesthesia care unit (PACU) after surgery BMI ≥ 40 kg/m2  At the time of baseline measurements in the PACU, patients meet the following criteria:  Receiving ≤ 6 liters of supplemental nasal cannula oxygen Alert as defined by a Richmond Agitation Sedation Scale of 0 or -1 Oriented to person, place, and time  Exclusion Criteria:  Pregnancy, suspected pregnancy or less than six weeks postpartum Known or current pneumothorax  Hemodynamic instability at the time of study assessment in the PACU defined as:  systolic blood pressure <90 mmHg or >180 mmHg mean blood pressure <60 or >130 mmHg Any use of intravenous vasoactive agent heart rate < 50 or > 120 beats per minute  Respiratory insufficiency in PACU defined as:  Respiratory rate > 30 Oxygen saturation < 92% Receiving > 6 liters of supplemental oxygen Known chronic lung disease requiring supplemental oxygen at home Known systolic heart dysfunction (left ventricular ejection fraction ≤ 30%)  Contraindication for esophageal catheter placement:  Known esophageal varices Known bacterial sinusitis Recent esophageal, nasopharyngeal, or laryngeal trauma or surgery Known coagulopathy: including history of thrombocytopenia defined as platelet count <50,000; presence of hemophilia; known genetic disorder of coagulation (e.g.,deficits of protein C, protein S, von Willebrand factor) or oral and subcutaneous anticoagulation treatment (e.g., heparin, warfarin, and or other oral anticoagulants)  Contraindication for electrical impedance tomograph belt placement:  Pacemaker and/or internal cardiac defibrillator Chest skin injury Concern for study inclusion by the perioperative nurse or anesthesia team - HealthyVolunteers: No - Gender: All - MinimumAge: 18 Years - StdAgeList: Adult, Older Adult