Cough Reflex and Obstructive Sleep Apnea Syndrome

Bichat Hospital

Status

Completed

Conditions

Sleep Apnea Syndrome

Treatments

Procedure: Cough reflex test

Study type

Interventional

Funder types

Other

Identifiers

NCT00317083

JG-2006-BCH

Details and patient eligibility

About

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).

Full description

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.

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Obese patient scheduled to undergo bariatric surgery

Exclusion criteria

Age less than 18
Active smoking
Psychotropic medication
Angiotensin-converting enzyme inhibitor or angiotensin II receptor antagonist medication
Pregnancy
Anesthesia or endotracheal intubation during the previous month
Allergic rhinitis
Upper airway or bronchopulmonary infection during the previous month
Chronic cough
Chronic respiratory disease
Pharyngolaryngeal disease
Neurological disease