FLOW-VOLUME CURVES REFLECT PHARYNGEAL AIRWAY ABNORMALITIES IN SLEEP-APNEA SYNDROME

Abstract

Patients (29) with disorders of excessive somnolence were evaluated with standard nocturnal polysomnography, fiberoptic laryngoscopy and flow-volume curves. Twenty-two had evidence of obstructive sleep apnea (OSA) by polysomnography and most had abnormal flow-volume curves, supporting earlier observations. Of 7 patients without obstructive sleep apnea, 3 also had abnormal curves. Fiberoptic nasopharyngoscopy was performed in the OSA group while awake to evaluate the upper airway. Sixteen patients of the OSA group demonstrated pharyngeal obstruction; 14 of those with visualized airway obstruction had flow-volume abnormalities. In the 6 patients of the OSA group with no significant visual obstruction, 5 had normal curves. The flow-volume curve appears to correlate with direct visual assessment of upper airway patency during wakefulness in those patients demonstrating obstruction during sleep.