Obstructive sleep apnoea

Definition

Obstructive sleep apnoea is characterised by repetitive episodes of apnoea or hypopnea that are caused by upper airway obstruction occurring during sleep. These events often result in reductions in blood oxygen saturation and are usually terminated by brief arousals from sleep. Excessive sleepiness is a major presenting complaint in many but not all cases. Reports of insomnia, poor sleep quality, and fatigue are also common. Upper airway resistance syndrome shares the same pathophysiology and should be classified here. In adults (> 18 years), obstructive sleep apnoea is diagnosed when the frequency of obstructive events (apnoeas, hypopneas or respiratory event-related arousals) is greater than 15 per hour. The disorder may also be diagnosed when the frequency is greater than five per hour and: a) symptoms attributable to the disorder (e.g., sleepiness or sleep disruption) are present; or b) nocturnal respiratory distress or observed apnoea/habitual snoring are reported; or c) when hypertension, a mood disorder, cognitive dysfunction, coronary artery disease, stroke, congestive heart failure, atrial fibrillation, or type 2 diabetes mellitus are present. In children, the disorder is diagnosed when the frequency of obstructive events is greater than one per hour, accompanied by signs or symptoms related to the breathing disorder. Note: A definitive diagnosis requires objective evidence based on polysomnography.

Exclusions

• Obstructive neonatal apnoea

Index Terms