Cough Reflex and Obstructive Sleep Apnea Syndrome
Up to 70% of obese patients undergoing bariatric surgery have obstructive sleep apnea syndrome (OSAS). OSAS is responsible for laryngeal sensory impairment. As the afferent neural pathway involved in the initiation of cough is located in the laryngeal epithelium, cough reflex sensitivity may be decreased in obese OSAS patients. The researchers therefore conducted this study to determine the effect of OSAS associated with obesity on cough reflex sensitivity, assessed by cough reflex threshold to an inhaled irritant (citric acid).
|Study Design:||Allocation: Non-Randomized
Endpoint Classification: Pharmacodynamics Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Diagnostic
|Official Title:||Effect of Obstructive Sleep Apnea Syndrome Associated With Obesity on Cough Reflex Threshold to Citric Acid|
- To compare cough reflex threshold to citric acid between obese OSAS patients and obese non-OSAS patients
- To correlate OSAS severity assessed by apnea-hypopnea index and cough reflex threshold to citric acid
|Study Start Date:||November 2001|
|Estimated Study Completion Date:||February 2003|
Obese patients undergoing scheduled bariatric surgery underwent a cough challenge as part of their routine preoperative evaluation. Patients were classified as presenting OSAS if apnea-hypopnea index obtained from preoperative full-night polysomnography was greater than 5/hour. Cough threshold was measured with citric acid. Increasing concentrations of mouth- nebulized citric acid (2.5, 5, 10, 20, 40, 80, 160, 320 and 640 mg/mL) were delivered during inspiration until a cough was elicited. The citric acid concentration eliciting one cough (C1) was defined as the cough reflex threshold.
|Anesthesiology Department, Bichat Hospital|
|Paris, France, 75018|
|Principal Investigator:||Jean Guglielminotti||Anesthesiology Department, Bichat Hospital|