Sleep Tests - Explanation of Procedures

After a comprehensive evaluation, noninvasive and painless testing options will be discussed. All patient rooms are private in the Sleep Disorders Center.

Polysomnogram (PSG) Test
This is an overnight test to monitor sleep cycles and identify disturbances. Several electrodes are attached to the scalp and body to record electrical activity in the brain and muscles. Other sensors detect eye movements, breathing activity, oxygen levels in the blood, snoring and electrical activity in the heart. A sleep technologist monitors the digital video recording by utilizing a special software program to collect the data. Test results are not available to the patient the next morning as the confidential file will require extensive analysis by a polysomnographic technologist and a sleep physician. You will review the results during a follow-up appointment..

Continuous Positive Airway Pressure (CPAP) Titration Test
Continuous Positive Airway Pressure. This is an overnight sleep study if you are diagnosed with sleep apnea. A small machine blows filtered, humidified air through a small clear plastic mask that covers the patient's nose. This gently pressurized air serves as an internal pneumatic splint to hold the airway open during sleep, making breathing easier. In Obstructive Sleep Apnea, the shape of a person's airway combined with the natural tendency for muscles to relax during sleep reduces the size of the upper airway, interfering with breathing.

In some cases, the technologist may perform a CPAP titration study on the same night as a sleep test. This is known as a split-night sleep study and occurs in the second half of the night. This is usually only offered if the sleep apnea is severe, and the diagnosis is clear.

During a CPAP titration test, you'll have virtually all the same monitoring sensors as a polysomnogram, and you will wear a CPAP mask. This allows the sleep team to calibrate your CPAP equipment so that it will work best for you. During the study, a patient's breathing is monitored, and the CPAP pressure is adjusted to determine the proper air pressure required to prevent upper airway blockage, eliminating pauses in their breathing while sleeping. 

Electroencephalography (EEG) Test: Daytime test to provide a more extensive recording of the electrical activity in the brain.

Multiple Sleep Latency Test (MSLT)
This consists of five naps precisely scheduled two hours apart during the day. This test is typically conducted the day after a polysomnogram. You should bring your meals, as well as work, schoolwork, books, or magazines to pass the time between naps. You may take and make phone calls between naps. You are required to stay awake and out of bed between naps, and avoid caffeine. Smoking is discouraged, and not permitted inside the building. If you prefer, we will provide you a cold breakfast and lunch from the hospital café.

Maintenance of Wakefulness Test (MWT)
Daytime polysomnographic procedure to monitor how alert you are during the day. In some cases, your ability to stay awake may be more important than how fast you fall asleep. The test is performed in a quiet, dark and non-stimulating atmosphere. Avoid caffeine and tobacco products prior to this test.

Office Locations at Barnes-Jewish West County Hospital

Sleep Medicine Center, BJC Medical Group Physicians
969 N. Mason Road, Suite 250
Medical Office Building 969
Creve Coeur, MO 63141

Sleep and Electroencephalogram (EEG) Lab, BJC HealthCare
969 N. Mason Road, Suite 260

Barnes-Jewish West County Hospital is conveniently located just one mile west of I-270 in Creve Coeur, Missouri — a west county suburb of St. Louis.

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Contact Us

Physician appointment changes or cancellations should be submitted through MyChart, or by calling your physician office directly.

For immediate assistance or to schedule an appointment with one of our sleep specialists, please call 314.996.8680.

Find additional phone numbers here.