SLEEP STUDY

What is a sleep study?

A sleep study checks your breathing, pulse, and brain waves as you sleep. This test is often done to diagnose if a person has sleep apnea. A sleep study checks the following variables:

• Brain waves-a device measures your brain waves as you sleep. Patches called electrodes are placed on your head. The electrodes connect to wires on a device that records the electrical activity in your brain.
• Chin and eye movements-a device measures these movements, which show the different stages of your sleep.
• Heart rate and rhythm-an electrocardiogram (ECG or EKG) measures heart activity. Electrodes are put on your chest, neck, arms, and legs. The ECG shows if you have abnormal heart rhythms (arrhythmias) during sleep.
• Breathing movements-chest bands measure your chest movements.
• Oxygen levels-a monitor checks oxygen in your blood.

How is sleep related to your health? Sleep apnea is a disruption in breathing during sleep. And sleep apnea is often linked to certain heart and blood vessel conditions, such as high blood pressure and atrial fibrillation.

What can I expect?

If your doctor orders an overnight sleep study, you usually stay overnight at a special sleep center or sleep lab. You answer a series of sleep-related questions before going to bed in a private room. You have a number of electrodes on your body, but there typically is no pain involved in the test. While you sleep, monitors record all of the functions listed above.

In some cases people take home a small monitor that measures many of these same functions. A technician first explains how to use the home monitoring system. Then you use it while sleeping at home in your own bed. When you return the monitor, the stored data is analyzed.

No matter witch type of test you have, the test result help your doctor find out the cause of your breathing problem. The test can also reveal the best way to treat your sleep apnea.