ABSTRACT
INTRODUCTION Sleep-related breathing disorders (SRBDs) are a group of disorders characterized by disordered respiration in sleep. Of these, obstructive sleep apnea (OSA), a form of sleep-disordered breathing (SDB), is the most commonly encountered condition. The syndrome of OSA is characterized by repetitive episodes of complete (apnea) or partial (hypopnea) upper airway obstruction during sleep, often resulting in snoring, arterial oxygen desaturation, and arousal from sleep. The upper airway resistance syndrome (UARS) is believed to be a milder version of OSA, although there is contra diction, and it is presumed to have the same risk factors as OSA (see also Chapter 18).
