Also known as: sleep study, PSG.

What is polysomnography?

Polysomnography is a diagnostic sleep test conducted on a child while they sleep to diagnose sleep-disordered breathing (SDB) in children.

During the study record continuous and simultaneous recordings of multiple body measurements (including brain waves, blood oxygen level, heart rate, breathing and others) are made to identify sleep breathing abnormalities like obstructive sleep apnea syndrome (OSAS- associated with snoring, gasping, mouth-breathing or sleeping in unusual positions), or associated with head/face (craniofacial) abnormalities, neurological and muscular disorders that may cause obstruction to the nose/windpipe (nasotracheal or upper airway abnormalities) and other conditions.

What happens during the procedure?

Polysomnography takes place at a sleep center at night and normally takes one to two hours. The child is made comfortable and gets ready to sleep in a room that is often similar to a hotel room. A technician places sensors on various parts of the body to take measurements, recordings and observations (recorded by camera) while the child sleeps. A blood test may be taken afterwards.

Is any special preparation needed?

Your child may need to refrain from caffeine and perhaps medications for a period of time before the test.

What are the risk factors?

There are very few risk factors associated with polysomnography. Occasionally sensors attached to the skin may cause irritation, or if blood is drawn there are rare problems associated with this.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: March 02, 2020 12:24 PM

What is a Sleep Study? - What to expect when you stay at the Sleep Lab

In this video, we will explain what to expect during your child's stay at the sleep lab. A sleep study is also called a Polysomnography. This is a test used to diagnose sleep disorders. Polysomnography records your brain waves, the oxygen level in your blood, heart rate and breathing, as well as eye and leg movements during the study.