Pathophysiology of obstructive sleep apnea.

This article explores the physiologic basis and symptoms of obstructive sleep apnea--a general term encompassing central sleep apnea and obstructive sleep apnea. The former is relatively uncommon while the latter is much more common. Episodic collapse and blockage of the upper airway occur during sleep despite continuous respiratory effort. Three types of sleep obstructive breathing--apnea, hypopnea, and airway resistance--are associated with respiratory-related arousals from sleep.