Sleep Tests - Explanation of Procedures

Polysomnogram (PSG) Test
About 25 painless, noninvasive electrodes and sensors will be applied to the surface of your skin. These devices monitor several physical characteristics, including EEG (brain electrical activity), EOG (electrical activity signaling eye movements), EMG (muscle electrical activity), EKG (heart electrical activity), various measurements of breathing, respiratory effort, snoring, oxygen level in the blood, and digital video recording of your sleep. Video copies are not available to patients because they are recorded in a special software program. The video recording is completely confidential - as are all your test data.

The polysomnogram is recorded in a computer, and reviewed later by a polysomnographic technologist and a sleep physician. These physiological parameters are also monitored live, in real time, by a trained technologist. Test results are not available the morning after your test - they require extensive analysis later by the sleep physician. Your sleep doctor will provide you your detailed test results, usually at your follow-up appointment.


Home Sleep Apnea Test
The Home Sleep Apnea Test is a test designed specifically to diagnose obstructive sleep apnea. Sensors record airflow, respiratory effort and oxygen levels in the blood. The patient is shown how to apply the wires in the lab and goes home to complete the overnight test.

Continuous Positive Airway Pressure (CPAP) Titration Test
Continuous Positive Airway Pressure. Due to its success, it is often used as a treatment for obstructive 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.

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. The test is devoted to finding the gentlest pressure that effectively improves breathing.

Polysomnogram + CPAP Titration Test
Most polysomnograms are conducted in a split-night format. This means a trial CPAP titration may be started if certain conditions set in advance by your sleep doctor are observed during the night. In order to provide the best, most accurate test possible, it is not possible to predict for any individual that a polysomnogram and CPAP titration can be concluded in a single night. However, it is often possible to conclude both in a single night.

Multiple Sleep Latency Test
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
This step measures your ability to stay awake in a quiet, dark, non-stimulating atmosphere. Conducted in a format similar to the Multiple Sleep Latency Test, except you are requested to remain awake during the nap opportunities. Just as with the Multiple Sleep Latency Test, avoid caffeine and tobacco products.

Contact Us about sleep disorders or to schedule a sleep study

Let our sleep professionals help you get a better night's rest. For more information or to schedule an appointment with one of our sleep physicians, call 314.996.8680.

The Sleep Disorders Center at Barnes-Jewish West County Hospital is located just one mile west of I-270 in Creve Coeur, Missouri — a west county suburb of St. Louis. The address is at 969 Mason Road, Suite 260, near the corner of North Mason and Olive Boulevard.

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To schedule an appointment

To schedule an initial consultation or a sleep study call 314.996.8680.

The Sleep Disorders Center
969 Mason Rd., Suite 260

Private Sleep Lab Room
The Sleep Disorders Center at Barnes-Jewish West County Hospital


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