Recovery of Ventilation After General Anesthesia in Morbidly Obese Patients

Not Recruiting

Trial ID: NCT03925610


This is an observational study of morbidly obese patients recovering from general anesthesia after weight-loss surgery. The investigators aim to assess ventilatory function and how this is influenced by the diagnosis of obstructive sleep apnea (OSA), baseline ventilatory status, as well as pharyngeal collapsibility of patients who are recovering from anesthesia and treated for pain with opioids. The investigators hypothesize that patients with OSA, chronic (baseline) hypoventilation and increased pharyngeal collapsibility, will be more vulnerable to opioid-induced ventilatory depression.

Official Title

Recovery of Ventilation After General Anesthesia in Morbidly Obese Patients Who Are Treated With Opioids: A Preliminary Investigation

Stanford Investigator(s)

Anthony G. Doufas, M.D., Ph.D.
Anthony G. Doufas, M.D., Ph.D.

Professor of Anesthesiology, Perioperative and Pain Medicine


Inclusion Criteria:

   - Body mass index (BMI) equal or greater than 35 kg/m2.

   - American Society of Anesthesiologists (ASA) physical status I - III patients.

   - Scheduled to undergo laparoscopic roux-en-Y gastric bypass or gastric sleeve placement
   surgery for weight loss.

Exclusion Criteria:

   - Chronic obstructive pulmonary disorder (COPD).

   - Treatment with continuous positive airway pressure (CPAP) in the past three months.

   - Severe neurological, cardiopulmonary, psychiatric, or untreated thyroid disorder.

   - Chronic pain condition that was being treated with opioids.

   - Patients with a hematocrit lower than 35%.

Not Recruiting

Contact Information

Stanford University
School of Medicine
300 Pasteur Drive
Stanford, CA 94305
Anthony Doufas, MD, PhD