Obstructive sleep apnea
Obstructive sleep apnea (OSA) is the most common type of sleep apnea and is characterized by repeated episodes of complete or partial obstructions of the upper airway during sleep, despite the effort to breathe, and is usually associated with a reduction in blood oxygen saturation. In the Obstructive Sleep Apnea-Hypopnea Syndrome, the episodes of decreased breathing are called "hypopnea" and its definition requires a ≥30% drop in flow for 10 seconds or longer, associated with ≥3% oxygen desaturation. The episodes of breathing cessations are called "apneas" (literally, "without breath") and to be defined, a ≥90% drop in flow for 10 seconds or longer must be assessed and associated with ≥3% oxygen desaturation, or an arousal.
Obstructive sleep apnea-1