What is a sleep study?
A polysomnogram (overnight sleep study) is noninvasive, painless test that
lasts generally one night. It involves recording vital signs and other
physiologic variables during a night of sleep in the bedroom laboratory.
Should I do anything differently the day before my sleep study?
- Do not take a nap the day before your sleep study.
- Do not have caffeine, coffee or tea starting at noon on the day of your
sleep study appointment.
- On the day of your appointment you should shower and wash your hair. Clean
and dry hair is necessary for the application of electrodes to your scalp.
Avoid using any hair products, including conditioner, hair spray, or mousse.
Refrain from using skin lotions and powders.
- Bring any medications you may need during the night. Avoid stimulants or
sedatives unless approved by your physician. Please ask the Sleep Center
staff if you are unsure about how the medications you take may affect
your sleep study.
- Eat a normal evening meal before your arrival. If you normally eat a small
snack before bed, you may bring one with you. No more than your usual
intake of alcoholic beverages the day of your study.
- Bring toiletries (toothbrush, toothpaste, etc.) and appropriate sleepwear.
Sweats, shorts, cotton or flannel nightgown, or pajamas will be fine.
(Please no sheer or revealing clothing).
- For a more comfortable stay, you may also bring your own pillow & blanket,
if you prefer.
- Please leave all valuables, such as jewelry, money, etc., at home.
- The use of line powered 120 Volt appliances are prohibited (i.e. heating
blankets, space heaters, etc).
What happens after I check in?
You will be asked to complete sleep questionnaires about your sleeping
habits, the day's events, medications taken, and so on.
A sleep technologist will ask you to change into your night clothes or
a hospital gown. Small sensors or electrodes will then be attached to
parts of your head and body using a water-soluble paste and tape. Flexible
wiring is attached to the sensors, which are then connected to a central
unit. If you are allergic to adhesive, please notify your tech so, we
may use a skin barrier for your protection. A monitoring area is located
close to your room. Once all of the sensors, electrodes, and belts are
attached, the technologist will take some initial readings while you are
awake. You may then read or watch TV before you are ready to go to sleep.
What happens while I am asleep?
The attached sensors monitor and record various physical activities, such
as heart rhythm and rate, eye movements, muscle activity, breathing, leg
movements, and blood oxygen levels. Depending on the symptoms you have
described to the sleep specialist, some or all of the following will be
- Brain activity - Multiple sensors attached to your scalp record your brain
waves. This reading shows the technologist which sleep stage you are in.
- Airflow - A sensor placed on your upper lip monitors the airflow in and
out of your nose and mouth.
- Rapid eye movements - One or two sensors placed on the head next to the
eyes record rapid eye movements (REM), which are associated with dreaming.
- Breathing - Elastic belts around your chest and stomach measure your respiratory effort.
- Heart rate - Your heart rate and rhythm are monitored with multiple sensors
attached to your chest.
- Oxygen level - A device that measures oxygen levels, is clipped or taped
to your finger. In patients with sleep apnea, this measurement can determine
how severe the apnea episodes are.
- Leg movements - Sensors are placed on your legs, usually on the shins below the knee.
One or more technologists will observe you the entire night while you sleep
using an infra-red video camera. Technologists note if you snore and how
loudly, or if you have periodic body movements. They also chart your sleep
stages and other measurements. The next step is for you to get comfortable
and go to sleep!
Some patients need to spend more than one night in the sleep lab. This
will be determined by one of our sleep physicians after the sleep study
results are processed and interpreted. These results will be discussed
with you at your scheduled follow-up visit.
What will happen the next morning?
- After you wake up in the morning, the technologist will remove the equipment
and adhesive tape. You will also be asked to complete another questionnaire
about your night's sleep.
- You should be able to leave between 6am -7am. Unless, you are scheduled
for possible MSLT testing.
- If you are scheduled for a possible Multiple Sleep Latency Test (Daytime
Nap Study), you will find out at 6am if you will need to stay for further
testing. Please, read over the following information as you may stay at
our center, in some cases, as late as 4pm.
- We will supply breakfast and lunch. Special diets are available as needed.
You are also welcome to bring your own food if you prefer. No caffeine
is allowed during this testing process.
- Bring any medications you may need during the day (except stimulants).
- Bring clothing, such as a sweat suit, that is comfortable to nap in. Bring
things to do (books, correspondence, laptop etc.) to keep you busy between naps.
- No smoking is allowed inside the Sleep Center
- On the day of the nap study you will be asked to submit a urine sample
for a qualitative drug screen
How do I get the paste out of my hair/off my scalp?
The best option is to use very warm to hot water and shampoo. There are
showers available in the Sleep Center.
Can I get shocked from the wires and sensors?
No. It is impossible because the electrodes and sensors detect the electrical
and physical signals that you produce. There is no electricity being sent
through the wires to the sensors on your body.
What if I need to go to the bathroom during my sleep study?
Don't worry - disconnecting the wires to the nearby unit is a fairly quick
process and a technologist is always awake and available to help you.
You only need to call out and the technologist will come in and disconnect
Will I be able to sleep during my polysomnogram?
This is a very common question. Most people doubt their ability to sleep
in the lab, especially if they are unable to sleep well at home. Sleep
technologists find that most patients sleep better in the lab than at
home. It could be due to the fact that some people feel more secure or
less distracted in the lab than at home. Some individuals are simply relieved
that someone is taking an interest in their problem, it will soon be diagnosed,
and they are on the road to better sleep. Even if you do not sleep well
in the lab, polysomnographic testing will most likely be able to determine
a great deal of information.
How much notice do I need to give if I want to cancel or reschedule my
If you need to cancel or change the sleep study appointment, please give
our office a minimum of 24 hours notice, doing so would allow our office
to call another patient in your place.