Sleep apnea--diagnosis and treatment.

T he syndrome of sleep apnea has been described throughout the ages, dating at least to descriptions of Dionysius the Tyrant in the fourth century BC. It is only recently that scientific investigation has led to an understanding of this previously ill-defined syndrome. Sleep apnea is the currently accepted term for a group of heterogeneous sleep-associated respiratory disorders. The most common of these is obstructive apnea, which is defined as a cessation of airflow during continuous respiratory effort. Obstructive apnea occurs when oropharyngeal pressures be-