What should I expect during a sleep test?

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)
If you have sleep problems and your doctor decides to give you a sleep test, called polysomnography, you may be asked to spend the night at a sleep center or hospital. The test records your brain waves, the oxygen level in your blood, your heart and breathing rate, and your eye and leg movements during sleep.

A sleep test is noninvasive and painless. You can bring your own pajamas, and the room is usually similar to a hotel room. It's dark and quiet, and you don't have to share the room with anyone else. (That might be a welcome change from snoring partners or middle-of-the-night visits from kids!)

The room has an infrared camera so the technologists can monitor what is happening in the room. There is also an audio system so they can talk to you and hear you from their monitoring area outside the room.

You will need to sleep with a sensor on your scalp, temples, chest, and legs, as well as a sensor on your finger to monitor the oxygen level in your blood. The sensors keep track of your brain waves as you sleep, so your doctor can keep track of your non-rapid eye movement (NREM) and rapid eye movement (REM) sleep.

It usually takes about two weeks to receive the results of the polysomnography. In your follow-up appointment, your doctor will review what they learned and discuss any treatment or further evaluation.

If your doctor does not recommend a sleep test, there are a number of other behavioral and environmental sleep therapies, as well as alternative treatments. You may even be able to do a professional sleep study at home. A small bedside device—prescribed by your doctor—has hookups for your heart rate, breathing, and other vitals that will indicate how well you are sleeping.

Before you undergo any sleep study, be sure not to drink alcohol or caffeine, take a nap, or take any sleep aids that might interfere with the results.

During a sleep test (also known as a polysomnography) you can expect to sleep in a dark, quiet and private room, similar to a hotel room, with its own bathroom. It's private in that you won't share it with anyone, other than a video camera. This is placed there so that the technologists can observe your movements while you sleep. There's also an audio system so you can communicate with one another. The sleep test is painless and noninvasive. It will record your brain waves, the oxygen levels in your blood, your heart rate, breathing and eye and leg movements.

You'll be able to sleep in your own pajamas (no hospital gowns required) and bring any items you normally use for your bedtime routine. Once you're ready to lie down, you'll be wired with sensors on various parts of your body like your scalp, temples, chest and legs, and your finger or ear will sport a small clip, which monitors oxygen levels in your blood. Sometimes, if sleep apnea is suspected, you'll be asked to try a positive airway pressure, or PAP, machine during the night to test out its effectiveness.

Following the visit, the doctor should be able to diagnose your condition and suggest treatment so that you no longer suffer from sleep problems. Treatments may include medications, medical devices such as PAPs or dental appliances to help with snoring. Treatment may also include nonmedical approaches like cognitive behavioral therapy.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.