Snapshot A 56-year-old man presents to your office for a fatigue workup. He describes his daytime sleepiness as "very distressing" as sometimes he feels like he may fall asleep while driving. He denies sudden losses of muscle tone or hallucinations before or after falling asleep. His BMI is 33. He often wakes up feeling tired and his wife often complains of his snoring. Introduction Clinical definition breathing disruption for at least 10 seconds repeatedly during sleep results in sleep disruption and consequent daytime fatigue Types central sleep apnea (CSA) no respiratory effort deriving from decreased CNS drive obstructive sleep apnea (OSA) physical airway obstruction may be caused by decreased pharyngeal muscle tone obese neck pressing on the upper airwary increased tonsil size most commonly seen in children nasal septal deviation more common in males associated conditions obesity Presentation Symptoms chronic fatigue similar to narcolepsy morning headache specific to CSA loud snoring specific to OSA Physical exam hypertension Evaluation Serology polycythemia due to chronic hypoxia stimulating EPO release Polysomnography sleep study can distinguish OSA from CSA ECG arrhythmias Treatment CSA nonoperative BiPAP provides mechanical ventilation OSA nonoperative weight loss reduction of alcohol intake prior to sleep smoking cessation CPAP (continuous positive air pressure) surgical anatomical correction of obstruction Prognosis, Prevention, and Complications Complications arrhythmias may result in sudden death most common in infants and elderly pulmonary hypertension due to chronic hypoxia stimulating pulmonary vasculature constriction may result in cor pulmonale