Obstructive sleep apnea and its therapy

1. Big picture

Obstructive sleep apnea (OSA) is a sleep-related breathing disorder caused by repeated collapse of the upper airway during sleep. The patient tries to breathe, but airflow stops or decreases because the pharyngeal airway is obstructed.

The key exam sentence:

Obstructive sleep apnea causes repeated nocturnal apneas/hypopneas, intermittent hypoxemia, arousals, fragmented sleep, excessive daytime sleepiness, and increased cardiovascular risk.

The most important exam trap:

Snoring alone is not enough for OSA. OSA requires obstructive apneas/hypopneas with oxygen desaturation, arousals, daytime symptoms, or associated cardiovascular/metabolic risk.

2. Defini