Polysomnography (sleep) study

Polysomnography study

Definition

Polysomnography (PSG) is a type of sleep study used to diagnose, rule out, or adjust treatment for sleep disorders such as obstructive sleep apnea (OSA), narcolepsy, periodic limb movements, and REM behavior disorder. A sleep study measures sleep cycles and stages by monitoring biophysiological changes that occur during sleep. These changes are recorded using electrodes attached to the patient. Some of the parameters measured are: air flow in and out of the lungs, blood oxygen levels, body position, brain waves using an electroencephalogram (EEG), breathing effort and rate, electrical activity of the muscles using electromyogram (EMG), eye movement using electrooculogram (EOG), and heart rhythm using an electrocardiogram (ECG). Sleep studies track how often the patient stops breathing for at least 10 seconds (apnea) and how often breathing is partly blocked for 10 seconds (hypopnea). Results reported include the Apnea-Hypopnea Index (AHI). An AHI of less than 5 is considered normal. Normal results would also include normal patterns for brain waves and muscle movement.

CLIN; Document; Finding; Findings; Point in time; Polysomnogram; PSG; Random; Sleep study; Study report