Obstructive sleep apnea (OSA) is a sleep disorder that involves cessation or significant decrease in airflow in the presence of breathing effort. Obstructive sleep apnea is a sleep disorder characterized by recurrent episodes of upper airway (UA) collapse during sleep.[1 ]By definition, apnea episodes last 10 seconds or longer and commonly last 30 seconds or longer. Apnea may occur hundreds of times nightly, 1-2 times per minute, in severe obstructive sleep apnea patients, and it is often accompanied by wide swings in heart rate, a precipitous decrease in oxygen saturation, and brief electroencephalogram (EEG) arousals concomitant with stertorous breathing sounds as a bolus of air is exhaled when the airway reopens. This may occur hundreds of times nightly. Obstructive apnea events are most often associated with recurrent sleep arousals and recurrent oxygen desaturation.
February 24, 2011