I have been performing Sleep Studies (Polysomnograms) as a Registered Polysomnographic Technologist (RPSGT) for approximately 15 years. Many people who come in for a sleep study are very apprehensive about what to expect. I try to put peoples minds at ease by saying something like "once we get the sensors on, all you have to do is sleep!" This is really the crux of the problem, however, because many patients either have trouble getting to sleep or staying asleep. Some just sleep too much. We have just opened a bag of worms and out comes the life story...
Most people who come in to the sleep lab have been dealing with sleep issues for years before they finally decide to do something. Sometimes it's the family who has been dealing it: the loud snorer who keeps everyone else in the house awake. The whole family's sleep problems can sometimes be solved by getting one person's snoring under control. When I ask why they are in the sleep lab, the most common answer? "My wife". And the most common cause of the wife's complaints? Snoring. Many times the patient is not even aware of the problem. This is where the cold hard data of a sleep study, or polysomnogram, can finally convince a patient to seek treatment. Snoring is not the only problem, however. There are a full 98 separate sleep disorders.
Sleep studies have been standardized over the years and quality Sleep Labs are accredited by the AASM, the American Academy of Sleep Medicine. If I were to have a sleep study done I would have it done in an accredited lab. Most insurance companies will also require the lab be accredited to guarantee coverage. The procedures done in an accredited lab will vary slightly, but not significantly, from one lab to the next.
Any person can refer themselves to been seen by a Sleep Specialist, usually either a Neurologist or a Pulmonologist. They would then refer you on to the Sleep Lab if they believe you need a sleep study to sort things out. Most referrals are for snoring, sleep apnea, periodic limb movements of sleep (related to restless leg syndrome), insomnia, or just plain excessive daytime sleepiness.
Most sleep studies occur at night, however sleep labs can accommodate individual schedules to some degree (for example, a night shift worker). A typical patient will probably arrive at the sleep lab around 8:00 Pm. They are taken to a private bedroom and shown around. Rooms have individual temperature controls and are usually quite comfortable. Some sleep labs are very plush similar to hotel rooms. Most have a private bathroom . You will be given some time to change into your pajamas and fill out a questionnaire about your day.
The technologist will then come back into the room and spend about 45 minutes applying sensors. There will be approximately 10 EEG (electroencephalograph) electrodes on your head (to tell when you are asleep and what stage of sleep you are in). There will be 2 respiratory belts, one around your chest and one around your abdomen, to record your breathing effort. You will have sensors in front of your nose and mouth to record how much air you are breathing in and out. Sensors by the eyes help to tell us when you are in REM (Rapid Eye Movement), or dream, sleep. Sensors on the chin also help to tell us when you are in REM or if you have bruxism (teeth grinding). There will be a mini-microphone taped near your face to record snoring and somniloquy (talking in your sleep). Three tiny sensors on each of your legs will record any leg movements. Your EKG, obtained by electrodes placed on your chest an abdomen, will detect any abnormal heart rates or rhythms. Finally, an oximeter on your finger will tell us your oxygen level.
All of these sensors are connected to wires and you will end up with a ponytail of wires coming off the back of your head. Usually people forget about the wires after a short time. You will be tucked into bed and talked to over an intercom with instructions to do certain movements to make sure all of the sensors are recording correctly. If everything is working right this is the point where we make sure you are comfortable one final time and then we say "goodnight". I always would like for patients to call me over the intercom if anything at all is bothering them, as far as wires pulling, or if they are cold, or just need a drink of water during the night. If you need to use the bathroom during the night you will need to call us over the intercom and just say "I need to get up" and we will come in to unplug you which only takes a couple seconds.
There will be a camera in the room to let us see what position you are sleeping in. Some sleep disorders are position-dependent so it is important to accurately see position.
Some people will have an intervention about halfway through the night to help their breathing. It is called CPAP, which stands for Continuous Positive Airway Pressure.
We hope to record at least 8 hours of sleep, but some people can be diagnosed with as little as 30 minutes of sleep. Typically we will wake people around 6:00 AM. It takes 5-10 minutes to get the sensors off. You will probably be asked to fill out a short questionnaire about how you think you slept. That's it! You may want to take a shower there or go home and do that, but you are free to leave the lab when you are ready.
In our lab it usually takes about a week to get the results. Over the course of the night of your sleep study we accumulate about 1000 pages of data that needs to be analyzed accurately. You will likely have a follow-up appointment with your physician to go over your results in about a week or two. Your study results and treatments available for your disorder will be discussed at that time.