TY - CHAP M1 - Book, Section TI - Obstructive Sleep Apnea A1 - Hudson, Arlene A2 - Freeman, Brian S. A2 - Berger, Jeffrey S. PY - 2016 T2 - Anesthesiology Core Review: Part Two Advanced Exam AB - Obstructive sleep apnea (OSA) is a syndrome of repetitive upper-airway obstruction during sleep. It is defined as five or more episodes per hour during sleep of complete airflow cessation (apnea) or a partial airflow reduction of 30%–99% (hypopnea) each lasting greater than 10 seconds, despite continued respiratory effort, and accompanied by a 4% decrease in oxygen saturation. Common associated symptoms include daytime sleepiness, impaired concentration, recurrent awakenings and restless sleep, and gasping/choking sensations during sleep. The condition is described by the Apnea-Hypopnea Index (AHI) that is derived from the total number of apneas and hypopneas per hour of sleep. The American Academy of Sleep Medicine defines mild OSA as AHI 5–15, moderate OSA as AHI 15–30, and severe OSA as AHI > 30. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessanesthesiology.mhmedical.com/content.aspx?aid=1135743880 ER -