Obstructive sleep apnea (OSA) is a disorder in which breathing stops for periods of at least 10 seconds during sleep. Partial or complete collapse of airway at the back of the throat decreases oxygen uptake and carbon dioxide release. Several apneic episodes during a night’s sleep disrupt normal sleep patterns, resulting in excessive daytime sleepiness and other symptoms of sleepdisordered breathing. The pauses in breathing can last 30 seconds or longer and lead to blood oxygen levels falling to as low as 40% in severe cases. This lack of oxygen causes the brain to briefly arouse the body from sleep to restore normal breathing, a pattern that can occur many times during a single night leading to fragmented sleep. Symptoms and effects of untreated OSA can include excessive daytime sleepiness, morning headaches, increased heart rate, elevated blood pressure, increased risk of stroke, increased risk of death due to heart disease, impaired glucose tolerance / insulin resistance, impaired concentration, mood changes, and increased risk for motor
vehicle accidents. The prevalence of OSA with excessive daytime sleepiness in adults aged 30 to 60 years is 2% in women and 4% in men.