A nocturnal polysomnogram, or PSG, is a sleep test used in the diagnosis and/or treatment of sleep disorders. Some common symptoms of sleep disorders that may prompt your physician to order a polysomnogram are snoring, excessive daytime sleepiness, gasping or choking during sleep, and excessive movements during sleep.
What can I expect during a sleep study?
Typically, you will arrive at the sleep center at 9:30PM. The technologist will have you fill out a brief questionnaire, then change into your bedtime attire. He or she will then attach numerous sensors and electrodes to you; a painless process. These sensors and electrodes are tied together and plugged into a lightweight portable box that you can carry over your shoulder with ease. Once you are in bed and the equipment has been calibrated, you will try to fall asleep as if you would at home. If you need to visit the restroom at any time, the technologist can quickly and easily disconnect the box from the computer, allowing you to get out of bed. The test will typically end at 6:00AM. If you have previously been diagnosed with Obstructive Sleep Apnea (OSA), you will also wear a device called CPAP (Continuous Positive Air Pressure), which will deliver forced room air to your airway. The technologist will increase the amount of air you receive until you no longer snore and your airway remains free from obstruction.
How should I prepare for the study?
- Tell your sleep specialist about any medications that you take to receive specific instructions about any changes that may be required during the day of your polysomnogram. Typically, you will take all medications as usual, including sleep aids that you routinely take.
- Shower prior to the test to allow for good conduction of your body’s natural electrical signals to the electrodes, which will be applied to areas of the face and scalp. Patients should remove makeup and avoid using lotions prior to the test.
- Avoid caffeine and alcohol consumption several hours prior to the test.
What if I don’t sleep?
Many patients are afraid that they won’t sleep and that the test will be rendered inconclusive as a result. It is uncommon for patients to have excessive difficulty falling asleep, but some difficulty is expected due to the foreign sleep environment and the consciousness of the equipment. Patients can sleep in the position they prefer to. Even if there is only a few hours of sleep during a polysomnogram, there is often enough data to diagnose a sleep disorder if one is present. The test is not designed to be a carbon-copy of your typical night’s sleep. Patients will often spend time watching television or reading prior to the start of the test as a means to unwind.
What if I have work in the morning?
Many patients are ready to leave the sleep center within 15 minutes of the test’s conclusion. Electrode conduction paste residue is water-based and can easily be removed in the shower. If necessary, accommodations can typically be made to allow for an even earlier departure for patients who have early work schedules.
Will the technologist be watching me all night?
Although video recording is part of a polysomnogram, the technologist will be monitoring the signals produced by the sensors and electrodes. The video recording is not typically useful to the technologist during the test.