Polysomnographic evaluation of propofol-induced sleep in patients with respiratory sleep disorders and controls

Objectives/Hypothesis The treatment for obstructive sleep apnea syndrome (OSAS) depends on correct localization of upper airway obstruction, exception made for continuous positive airway pressure (CPAP). Drug-induced sleep endoscopy (DISE) with propofol allows this evaluation, but the drug effects on sleep parameters are not yet well established. Our objective was to study by polysomnography (PSG) whether propofol would change sleep parameters by means of a prospective cross-sectional clinical study in a tertiary hospital. Study Design Thirty non-obese subjects (6 controls and 24 OSAS patients) underwent two daytime PSGs, one with DISE and the other without DISE. Methods During DISE exam, propofol was administered intravenously in continuous infusion using a target-controlled infusion pump. The parameters evaluated were: presence of snoring, apnea-hypopnea index (AHI), oxyhemoglobin saturation (SaO(2)), and sleep macroarchitecture. Results Snoring was absent in all healthy subjects during DISE sleep with propofol, and present in all OSAS patients (100%). AHI and mean SaO(2) showed no statistical difference between the two tests, with and without propofol. However, minimum SaO(2) was significantly lower during propofol infusion (88.64 for without vs. 85.04 for with propofol; P < 0.01). Regarding sleep macroarchitecture, the tests with propofol significantly increased N3 sleep and totally extinguished REM sleep (P < 0.005). Conclusions The results demonstrate that propofol significantly changes sleep macroarchitecture. However, the main respiratory parameters, AHI and mean SaO(2), remained unaffected. Thus, in order to determine the sites of obstruction, propofol DISE used with target-controlled infusion proved to be an effective drug for endoscopic evaluation of patients with OSAS.