Tag Archives: sleep testing

Sleep Tests during the Day?

Sometimes people also need to have their daytime sleep tested. There are two main tests, the Multiple Sleep Latency Test (MSLT) or the Maintenance of Wakefulness Test (MWT). In sleep centers the MSLT used primarily, so that’s the one we will discuss here.

The MSLT is conducted the day following an overnight study, and begins 2 hours after waking. Patients should sleep on their regular schedule the night before, and get dressed for the day. The patient lies down in bed, and allows himself to fall asleep. After 20 minutes the nap test is over. The test is repeated every two hours for a total of 4 or 5 naps. The data from all tests is averaged.

The sleep specialist is measuring how long it takes the patient to fall asleep, and whether the patient had REM sleep. This helps assess how sleepy the person is. It is considered normal to fall asleep in 15 minutes, sleepy if sleep occurs in less than 10 minutes. Narcolepsy is characterized by a sleep onset of less than 8 minutes, with 2 sleep onset REM periods. We’ll talk more about narcolepsy in the next post.

How to Have a Good Night at the Sleep Center

First of all, know that almost all people sleep just fine in the sleep lab. Before and during medical school I worked as a PSG tech, so I know this is true from seeing hundreds of people sleep well.
You’ll be asked to arrive at the lab about 7pm. You will work with one staff called a PSG Tech throughout your stay. He or she will show you the bedroom, and hook the testing equipment to you. They will monitor you throughout the night and unhook the testng equipment in the morning. If you need to use the restroom in the night, no problem, simply call out to let the Tech know.
Most sleep labs have bedrooms that look like hotel rooms with a double or queen-sized bed. You are welcome to bring your most comfortable pillow, and a favorite book or movie to enjoy before bed.

Keep in mind the information gathered during the overnight sleep study is so valuable in diagnosing and treating sleep problems that it is well worth it.