Study to Determine Incidence of Hypoventilation in Patients Who Have Undergone Gastric Bypass

This study has been completed.
Information provided by (Responsible Party):
University of South Florida Identifier:
First received: April 18, 2006
Last updated: September 18, 2012
Last verified: September 2012

The purpose of this study is to determine if gastric bypass patients experience hypoventilation in the immediate postoperative period, and to what degree.

Morbid Obesity
Bariatric Surgery

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: A Prospective Double Blind Pilot Study to Determine the Incidence of Postoperative Hypoventilation in Patients With Clinically Significant Obesity Who Have Undergone Gastric Bypass Procedures Under General Anesthesia

Resource links provided by NLM:

Further study details as provided by University of South Florida:

Enrollment: 20
Study Start Date: January 2006
Study Completion Date: October 2009
Primary Completion Date: October 2009 (Final data collection date for primary outcome measure)
Detailed Description:

We propose to determine if patients with clinically significant obesity (body mass index, BMI, between 40 kg/m2 and 85 kg/m2), who have undergone gastric bypass procedures under general anesthesia hypoventilate during the initial twenty-four hour postoperative period, and if so, to what degree. Adequacy of ventilation will be assessed by serial arterial blood analyses. Patients will be monitored for SpO2 in the preoperative holding area, in the operating room, and the post-anesthesia care unit (PACU) by conventional and study pulse oximeters. SpO2 data will be collected continuously and recorded on the study pulse oximeter for the entire study period. Arterial blood samples will be drawn for analysis every four hours by in-dwelling arterial catheter, using standard sterile technique. Hypoventilation is defined as an increase in PaCO2 five or more mm Hg above patient's baseline.


Ages Eligible for Study:   18 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

The study population will include male and female adult patients (age 18-65) with clinically significant obesity (body mass index (BMI) between 40-85 kg/m2), who are approved for gastric bypass surgery for weight loss. Patients must have documented obstructive sleep apnea and use continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP), and have an American Society of Anesthesiologists (ASA) Physical Status Classification I-III.


Inclusion Criteria:

  • Male and female subjects 18 to 65 years of age
  • Clinically significant obesity with a BMI between 40 and 85
  • Candidates approved for gastric bypass surgery at Tampa General Hospital (*Please note: authorization for gastric bypass will be completed prior to enrollment in study; this study does not pay for the cost of the operation.)
  • American Society of Anesthesiologists (ASA) Physical Status Classification I-III
  • Able to understand and sign informed consent

Exclusion Criteria:

  • Patients not able to understand the informed consent process, or unable to understand the research protocol
  • Patients in which placing an arterial catheter would pose a clinically unacceptable health risk, e.g., bleeding disorders, radial artery malformation
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Please refer to this study by its identifier: NCT00316446

United States, Florida
University of South Florida, Department of Surgery at Tampa General Hospital
Tampa, Florida, United States, 33606
Sponsors and Collaborators
University of South Florida
Principal Investigator: Scott F Gallagher, MD University of South Florida, Department of Surgery
  More Information

No publications provided

Responsible Party: University of South Florida Identifier: NCT00316446     History of Changes
Other Study ID Numbers: USF1
Study First Received: April 18, 2006
Last Updated: September 18, 2012
Health Authority: United States: Institutional Review Board

Additional relevant MeSH terms:
Obesity, Morbid
Body Weight
Nutrition Disorders
Respiration Disorders
Respiratory Insufficiency
Respiratory Tract Diseases
Signs and Symptoms
Signs and Symptoms, Respiratory processed this record on October 21, 2014