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FAQ’s About Sleep Studies


Facts About Sleep Studies
A sleep study, or polysomnogram, is a recording that includes measurements used to identify different sleep stages and classify various sleep problems. We urge you to learn more about sleep testing procedures before you arrive at the sleep disorders center so that your experience there will be easy and interesting.

Sleep is not a simple process. Many parts of the brain control it and influence its different stages. These levels or stages or sleep include drowsiness, light sleep, deep sleep, and dream sleep. It is possible to identify which stage of sleep a person is in by measuring different activities of the brain and body.

Monitoring Your Sleep
During sleep testing, the activities that go on in your body during sleep (brain waves, muscle movements, eye movement, breathing through your mouth and nose, snoring, heart rate, and leg movements) are monitored by small metal discs (called electrodes) applied to your head and skin with an adhesive. Flexible elastic belts around your chest and abdomen measure your breathing. The level of oxygen in your blood and your heart rate are monitored by a clip on your index finger or earlobe. Your sleep may also be videotaped for later review of any abnormalities observed during the study. The sleep technician will let you know if this is done.

None of these devices are painful and all are designed to be as comfortable as possible. If you have questions or concerns about the application of the electrodes (if, for example, you use a hearing aid or wear a hairpiece), contact you doctor or speak with the technician before you arrive at the center.

Analysis and Interpretation
The sleep study and its analysis and interpretation are part of a complex process. Specially trained professionals process or "score" the large amount of data recorded during the study. The information is then interpreted by a sleep specialist with special knowledge of sleep and its disorders.

Your Comfort
Many people expect the sleep center to be cold, bright, technical and impersonal-looking. However, the surrounding (and especially the bedroom) are homey and comfortable, like a hotel room. The technical equipment and technicians will be in a separate room, and the electrode wires will be gathered together in a kind of ponytail behind your head so that you will be able to roll over and change positions almost as easily as you would at home. The electrodes may feel strange on your skin at first, but most people do not find them uncomfortable or an obstacle to falling asleep.

Upon Arrival at the Sleep Center
When you arrive at the sleep center, the technician will greet you and show you to your bedroom. You will be shown the equipment that will be used and given a chance to ask questions. You should inform the technician of any changes in your sleep or specific difficulties you have not already discussed with your healthcare provider. You will have time to change into your nightclothes and get ready for bed just as you do at home. You can read, watch TV, or relax if there are any waiting periods before your study begins.

While you Sleep
The sleep center technician will monitor your sleep throughout the night from a nearby room. If a breathing problem is observed during your study, the technician may awaken you to ask you to try a device that treats breathing problems during sleep. If this is a possibility for you, you will be notified before you go to bed, and the use and purpose of the device will be explained. This device, called a positive airway pressure (PAP) device, includes a small mask that fits around your nose or your nose and mouth. If you will be having a PAP trial, the mask will be adjusted in advance to make sure it fits comfortably, and will usually give you a chance to practice with the device before you go to bed.

Additional Testing
Sometimes an additional test, called a multiple sleep latency test (MSLT), is needed as part of the overall sleep evaluation. This test requires that you stay at the center for most of the following day for a series of short naps beginning the morning after your overnight study. The naps are scheduled at set intervals throughout the day. Your sleep patterns will be monitored with most of the same recording equipment used the night before.

The Results
You will probably have a follow-up visit with your healthcare provider to discuss the results of your study and the recommendations for treatment. Be sure to inquire before your study about scheduling a follow-up visit. Some healthcare providers prefer that you wait until the sleep study results are available before the follow-up appointment is scheduled. Sleep study results are not generally discussed over the telephone because of their complex nature. To fully understand the results of your sleep study, their implications, and any treatment recommendations that are made, you should meet face-to-face with your healthcare provider.