Preparing for a Sleep Study

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What to expect during your stay at a sleep center


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You may have many questions as you prepare for a sleep study at a sleep center or lab. Knowing what to expect will help you feel more relaxed before and during the study. In fact, many people find that taking a sleep study is a fascinating experience.  Up until now, your sleep has probably been a mystery to you. You may not be sure why you aren't sleeping as well as you would like. The sleep study will help reveal some of the secrets and dispel some of the mystery of your sleep. It will show in very precise details exactly what happens while you are sleeping. This data will help detect the cause of your sleep problem. Then your sleep specialist will have a good idea of how to help you sleep better. Improving your sleep will help you feel better, think more clearly, and have more energy. It will be a great benefit to your overall health and quality of life.

Why Do I Need A Sleep Study?

Taking a sleep study in an accredited sleep center or lab is the best way to find out if you have a sleep disorder. It is the "gold standard" of sleep disorders diagnosis. Sleep is not a simple process. Many parts of the brain control your sleep in various stages. These stages of sleep include drowsiness, light sleep, deep sleep, and dream sleep. An overnight sleep study is the best way to analyze your sleep in all of its complexity. This kind of study is called a polysomnogram. It measures your brain waves, heart beat, and breathing. It also records movements of your eyes and legs. It shows your doctor the "big picture" of your sleep pattern. At the same time, it provides precise facts on what your body is doing at every moment of sleep. It combines a panoramic view with microscopic details. It is the most complete and scientific way to evaluate your sleep and discover any problems.

Preparing For A Sleep Study

Do not have any caffeine in the afternoon or evening before an overnight sleep study. This includes coffee, tea, cola, and chocolate. Also avoid drinking any alcohol. You do not want any substance to affect your sleep. Try not to take any naps that day. Before going to the sleep center, wash your hair with shampoo only. Dry your hair and do not apply any hair sprays, oils or gels. If used, they could interfere with the sensors during the study.

Pack an overnight bag to take with you to the center. Bring comfortable pajamas and a change of clothes for the morning. Include the same items you would take for a stay at a hotel. You may also want to bring your own pillow. Bring your medications if you will need to take them while you are away from home. If you have special needs or concerns, tell the sleep center staff ahead of time. They will do all they can to help you feel relaxed and at ease.

Should I take my medication as usual?

It is vital that your sleep specialist is aware of any medications that you are taking. This includes both prescription and non-prescription drugs. He or she should even know if you are taking common cold medicines or pain relievers. Certain drugs can affect your sleep and the results of the study. You may need to gradually stop taking some medications in the days leading up to a sleep study. Your doctor will let you know if this is something you need to do. Do not stop taking any prescription medication without first talking to your sleep specialist.

What Will Happen When I Arrive At The Sleep Center?

You will be told to arrive at the sleep center at a certain time in the evening. This is usually between 5:30 pm and 9:30 pm. One of the staff will greet you and lead you to your bedroom. A technologist will show you the equipment that will be used for the study. his will be a good time for you to ask any questions about how the study works. You should inform him or her of any recent changes in your sleep. Also tell him or her of any specific problems that you did not already discuss with your doctor. There will most likely be a few papers that you need to fill out at this point.

You will be given time to change into nightclothes and to make yourself at home in the bedroom. You should get ready for bed in the same way you do at home. There may be a waiting period where you have some extra time to relax. You can read or watch TV. When the technologist returns, be sure to confirm your wake-up time in the morning. Inform him or her if you have an early-morning commitment that you need to keep.

Next, about two dozen sensors are applied to the skin of your head and body with a mild adhesive. These small metal discs are called electrodes. They are connected to a computer and record the vital signs of your sleep. The wires are long enough to let you move around and turn over in bed. Flexible elastic belts around your chest and abdomen measure your breathing. A clip on your finger or earlobe monitors your heart rate and the level of oxygen in your blood. None of these devices are painful. They are all designed to be as comfortable as possible. The sensors may feel strange on your skin at first. But most people get used to them very quickly. They should not be an obstacle that keeps you from falling asleep. After everything is hooked up, you will do a test to make sure it is all in working order. You will be asked to move your eyes, clench your teeth and move your legs. Once it is all ready, you are free to read or watch TV until your normal bedtime. Then the lights are turned out and it is time for you to go to sleep.

You may have questions or concerns about having the sensors placed on you. Perhaps you use a hearing aid, wear a hairpiece, or have sensitive skin. Be sure to discuss these and any other concerns with your doctor before you arrive at the sleep center.

How will I be able to sleep in a strange environment with all those wires on me?

This is the question that people ask most often before a sleep study. Many people expect the sleep center to be cold and harshly lit. They imagine that their room will be like a small closet, filled with computers and beeping machines. But most sleep centers make you feel relaxed and comfortable. Their rooms are nicely decorated and may remind you of a hotel. It is so quiet and peaceful that most patients fall asleep quickly. It is expected that you might not sleep quite as well as you do at home. This should not hinder the study or affect the results.

What Happens During The Sleep Study?

The technologist will stay awake all night to monitor your sleep. He or she will be in a nearby room with the computers and equipment. You will be able to roll over and change sleeping positions as often as you like. The sensor wires are gathered together behind your head to give you the freedom to move in bed. During the night the technologist may ask you to spend some time sleeping on your back. This will provide better data on your breathing patterns. A low-light video camera may also record your sleep for later review. This will allow your doctor to see any unusual movements or behavior that may occur during you sleep.

While you are sleeping, important brain and body functions are measured and recorded. This may reveal that you have a breathing problem during sleep. A common example of this kind of problem is obstructive sleep apnea. In this case, the technologist may awaken you. He or she will fit you with a mask. It will either cover your nose or your nose and mouth. Another version has soft silicone tubes that fit directly in your nostrils. These are called nasal pillows. The mask provides you with a steady stream of air that gently blows into the back of your throat. This treatment is called positive airway pressure (PAP). While there are three kinds of PAP, the most common uses a level of pressure that remains continuous (CPAP).

You will try sleeping for the rest of the night with the mask. The technician will find the right level of air pressure to help you breathe normally as you sleep. This process is called a CPAP study. Usually your doctor will know in advance if there is a chance that this may occur. He or she will discuss this with you ahead of time. The use and purpose of the device will be explained to you in detail. You may even get to try on a mask and test it before your sleep study begins.

What if I need to go to the bathroom while I'm hooked up to all those wires?

This is actually a common and easy task. All you need to do is say out loud that you have to go to the bathroom. The technologist who is monitoring your sleep will hear you. He or she will come in to unplug your wires. All of the wires that are attached to you go into a central control box. The technologist will simply unplug the wires from the box and you will be free to get up. The sensors themselves do not need to be removed from your body. This makes it very easy to hook your wires back up when you return to bed. Most people have to get up at least once during the sleep study.

What Happens During A Nap Study?

Sometimes you may need to stay after your sleep study to take a daytime nap study. This study is called a Multiple Sleep Latency Test (MSLT). It is used to see how quickly you fall asleep in quiet situations during the day. The MSLT is the standard tool used to evaluate people who are thought to have narcolepsy. It may also be used to see if a person has hypersomnia. It begins between 1.5 and three hours after you wake up from the overnight sleep study. It consists of five nap opportunities with breaks lasting for two hours in between them. A shorter four-nap study may also be used. Your sleep patterns are monitored with most of the same recording equipment used the night before. The time it takes you to fall asleep will be measured. The kind of sleep you get during each nap will also be recorded. This is a valuable tool to help determine why someone is very sleepy during the day.

Be sure to plan ahead for a longer stay when you are scheduled for a nap study. You can call the center in advance to find out about breakfast and lunch plans. They can also let you know about what time the MSLT will be finished. Between nap trials, you will have to stay out of bed and occupy yourself so that you remain awake. You may want to bring things with you to work on or to entertain yourself. You can also ask about watching TV or videos between naps.

What Happens After My Sleep Study?

The analysis of a sleep study is a complex and time-consuming process. A typical sleep study produces about 1,000 pages of data. This information includes things such as brain waves, eye movements, and breathing patterns. It requires hours of work from a trained professional to accurately analyze the results. A sleep technologist processes or "scores" all of this data.  A sleep study is not something that you pass or fail. The scored results are simply given to a doctor for further evaluation. At an accredited center, this doctor must be a board-certified sleep specialist. The doctor will review the study to find out what kind of sleep problem you may have. Because of the detail and amount of time involved, it usually takes about two weeks for you to get the results. The doctor who ordered the study will discuss the results with you. If your primary care doctor ordered it, then the results are sent to him or her. If you met with a doctor in the sleep center, then he or she will tell you the results.


Your sleep does not have to be a mystery. A sleep study is a reliable, scientific, and painless way to find out why you don't sleep as well as you would like. It gives you valuable insight into the process of how you sleep. But it doesn't just give you understanding. It can also provide you with answers. With the results, a sleep specialist will be able to develop a plan of treatment to help you finally get the kind of sleep you want and need.

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