The KGH Sleep Laboratory is affiliated with Queen's University, Kingston, Ontario, Canada. Staff at the Sleep Disorders Laboratory at Kingston General Hospital developed this web site for patients being tested or treated for various sleep disorders.

Sleep Referral Form

We hope that this information will help you understand more about sleep and take an active role in your own care, and that your experience at our sleep lab will be positive and helpful to you.

• Why do I need a sleep study?
• What is a sleep study (Polysomnogram)?
• How are various body activities measured at the sleep lab?
• How do you expect me to sleep in such a different environment with all those wires on me?
• What if I need to go to the washroom or get up at night?
• Who will take care of me during the night?
• How can I prepare for my sleep study?
• What do I bring?
• How long will it take to get an appointment?
• Where Do I Go?
• Parking
• What happens when I arrive at the sleep lab?
• What else may happen?
• What happens after my sleep study?
• When will my family doctor get the results?
• What is the MSLT?
• What is the MWT?
• What is obstructive sleep apnea (OSA)?
• What is CPAP?
• What is an oral appliance?
• How do I get referred to the sleep disorders laboratory?
• Need more information?
• Links
• Sleep Physicians and Staff at the KGH sleep disorders laboratory
  

A sleep study is commonly performed to investigate the following symptoms:

• Unrefreshing sleep
• Daytime sleepiness
• Breath-holding episodes during sleep
• Loud snoring (to look for evidence of sleep apnea)
• Leg twitching / restless legs at night
• Abnormal behaviors at night (violent and non-violent behaviors in sleep)
• During sleep there are important changes in the brain and body, and disrupted or poor quality sleep can have an effect on mood, performance and our ability to function during the day.

To fully understand many sleep-related problems, we need to conduct an overnight sleep study. During the study, we monitor brain activity and body systems such as breathing, heart rate, leg movements and body position, and how they impact on your sleep throughout the night. Problems that can be diagnosed from an overnight sleep study include:

Sleep apnea - that is, when a person has repeated breath-holding spells during sleep.
Other breathing problems - for example, shallow breathing (hypoventilation).
Leg movements that disturb sleep.
Teeth grinding (or bruxism) that can disturb sleep.
Behaviour changes during sleep such as sleep walking or acting out dreams.

Figure 1. A sleep technologist wiring-up a patient in one of the bedrooms, for an overnight sleep study.

A sleep study, or polysomnogram, is a recording that contains several types of measurements that are used to identify different sleep stages, monitor breathing, heart rate and body movements and to assist in the diagnosis of various sleep problems.

Although sleep is a time of resting, some of the body systems are actually more active during sleep than when awake. Many parts of the brain control and influence the different stages of sleep. These sleep stages include drowsiness (stage 1 sleep), light sleep (Stage 2), deep sleep (slow wave sleep), and rapid eye movement sleep (REM sleep - the sleep stage when most dreaming occurs).

We can tell which stage of sleep a person is in by measuring different activities of the brain and body. These activities include brain waves, eye movements, and muscle tone.

For some sleep disorders such as sleep walking or talking, restless limb movements, or teeth grinding, you may also be videotaped during the sleep study for later review of any abnormalities observed during the study. The sleep technologist will let you know if this will be done and will ask for your signed consent.

Figure 2. This patient is wired-up for an overnight sleep study (polysomnogram). You can see the electrodes next to his eyes for recording eye movement and electrodes on his chin for monitoring muscle tone. The cannula at his nose and over his mouth records airflow. He has two electrodes on his chest for recording heart rate (ECG). Two stretchy belts, one on his chest and the other over his abdomen, record breathing effort.

The activities that occur during sleep (brain waves, muscle movements, eye movements, breathing, snoring, heart rate and leg movements) are monitored by applying small metal discs called electrodes to the head and skin. The majority of these electrodes are taped to the skin using hypoallergenic tape and those on the scalp and beards are kept in place using a water-soluble paste.

Flexible, stretchy belts are placed around your chest and abdomen in order to monitor your breathing. The level of oxygen in you blood and your heart rate are monitored by a device which clips on to your finger or earlobe.

Please inform the sleep technologist on arrival at the sleep laboratory if you have any allergies to certain tape or to latex.

This is the most frequently asked question by patients prior to their sleep studies. In fact, most patients have no trouble sleeping in the Sleep Laboratory despite wearing the recording equipment. During the test, you will sleep in your own private room. We have attempted to make the surrounding as comfortable as possible. The rooms are equipped for patients requiring oxygen or suctioning during the night.

If you have a particular pillow or blanket that you find comfortable to sleep with, please feel free to bring it with you for your sleep study. Each patient has his/her own separate bedroom. You may read in bed prior to the study or go to the television room in order to try and maintain your nightly routine. We prefer to have all our patients in bed by 11:30pm, so that we will have at least 6 hours of recording available to analyze.

The electrodes are gathered together in a kind of "ponytail" behind your head so that you will be able to roll over and change position almost as easily as you would at home. The sleep lab staff encourage patients to inform them if something is uncomfortable so that it can be fixed to help you sleep better.

During the sleep study you will be able to sleep in any position, turn over in bed, and get up to the bathroom. You may feel strange at first with the electrodes on your skin, however, most people do not find them an obstacle to falling asleep. The sleep specialist recognizes that you may not sleep in the lab exactly as you do at home, but in most cases this does not cause a problem in obtaining the necessary information from your study

.Figure 3. A view of one of the six bedrooms at the KGH sleep disorders laboratory. The wires for hooking onto the patient are arranged on the bed. On top of the nightstand cabinet, next to the bed, is a CPAP unit, which is used for the therapeutic or split night studies.

Figure 4. "Wired for sleep". In addition to the electrodes on the head and around the face for recording sleep, this patient has electrodes on the chest for monitoring his heart rate (ECG), bands around his chest and abdomen for monitoring breathing, a sensor for monitoring the flow of air through his nose and mouth. The probe for measuring oxygen levels through an oximeter is attached to his left index finger.

What if I need to go to the washroom or get up at night?

A call bell is located beside each bed so that you can contact lab staff during the night for washroom breaks, more blankets, etc.

A technologist will monitor the machines in an adjoining room and will be available at all times during the night should you require assistance. There is a sleep physician on call and available throughout the night, they receive a report from the technologist first thing in the morning.

On the day of your sleep study, avoid caffeine (coffee, tea, cola, and chocolate) after 2 p.m., and try not to nap. We ask men to shave if they do not have a beard or moustache. Women who usually shave their legs, may wish to do so, as there will be electrodes placed on the lower leg near the shinbone. Women should also remove their nail varnish and make-up and avoid excess hairspray. We try to avoid shaving men's chests for electrode placement to measure heart rate (EKG), but it is sometimes necessary to shave a small area for electrode placement.

BACK TO TOP

What do I bring?

Generally you will be booked for your sleep study within 4-8 weeks of your initial clinic appointment, unless special arrangements are made between you and the sleep physician. It is very important that you keep your appointment. Currently, the Sleep Disorders Lab at Kingston General Hospital has nighttime sleep studies on Monday, Tuesday, Wednesday, and Thursday nights. Appointments are booked for 8:30 or 9:30 p.m. If you must cancel a sleep study please phone 548-2382 (between 9a.m. and 2:30p.m.) or 549 6666 ext 3347 (after hours) so that a replacement can be found. We ask that you give 24 hours notice when possible.

The Sleep Disorders Lab at Kingston General Hospital is located on Kidd 6, near the public elevators. We ask our patients to check in with Security and to wait in the hospital lobby until a sleep technologist comes down to get you.

There is underground parking on Stuart Street across from the hospital's main doors. There is a cost for parking in this lot, the daily rate is about $10. There is no charge for parking overnight on the lakeside of the steam plant on King Street. If you park in this lot and have to stay after 7:30 a.m., you will have to move your car. The sleep disorders lab is not responsible for any parking violations. Please be ready to give your license plate number to Security when you come for your sleep study.

Once you have informed security that you are here for your appointment, a sleep technologist will meet you and bring you up to the lab and show you your bedroom. You will have time to change and get ready for bed.

There is a washroom within the lab, but please note that there are no shower facilities. You may wish to shower prior to your appointment.

Before the technologist begins applying the electrodes he/she may ask you some questions pertaining to your sleep or the equipment that will be used during the night.

You should inform the technologist of any changes in your sleep or specific difficulties that you might not have already discussed with your doctor. If you have a commitment in the morning (for example you have to be at work at a certain time), be sure to inform the sleep technologist prior to your study, so that a wake-up time can be arranged.

All patients should be in bed no later than midnight, unless prior arrangements have been made (for example for shiftworkers). Generally the study is ended somewhere between 6:00 and 8:00a.m. There are, however, special circumstances when patients are allowed to sleep past this time.

Lab work: Some of the patients coming to the sleep disorders lab require blood work in order to determine specific body functions, other patients may be asked for urine samples.

Video monitoring: Video taping of your sleep may be performed. If video taping is to be done, you will be asked to sign a consent form before the tape is shown to the sleep physician.

Split nights: Patients are usually notified about the possibility of having a "split night" study, which means that the first part of the night is a diagnostic study and the second part is the therapeutic component. You will receive some education about the procedure and device (please see the section on obstructive sleep apnea and CPAP) in clinic before coming to the sleep lab, or before going to bed. Please inform the sleep technologist if you prefer to wait until the sleep physician has reviewed the results of the sleep study with you before pursuing treatment. During the diagnostic part of the study, the sleep technologist will monitor your sleep and breathing from a nearby room throughout the night. If a respiratory or breathing problem is observed during sleep, the technologist may awaken you to ask you to try a device that treats breathing problems. If you do try the device and have noticed a benefit to your sleep, you may then be asked to seek a trial period of this device for a few weeks. You can then discuss your impressions and the study results with the sleep physician at a follow-up clinic visit.

After the study, the sleep physician receives a preliminary morning report from the sleep technologist about your study. The recording is "staged" for sleep by examining the 7-9 hours of the recording in 30second windows and is scored for breathing events, limb movements, or other features of sleep disorders by a sleep technologist. The record and report is then reviewed and interpreted by the sleep physician. Treatment recommendations will be made if evidence of a sleep disorder is found. Please let the physician know prior to your overnight sleep study if you wish them to review the findings with you.

A typical sleep study contains around 900 pages (in 30 second windows/epochs) of different types of data (e.g., brain waves, muscle movements, and eye movements) collected by a computer. The average sleep study takes approximately two hours to stage, score and analyze. Then the sleep physician interprets the findings and makes any treatment recommendations necessary. You will normally be scheduled for a follow-up clinic appointment with the sleep physician before you leave the sleep laboratory in the morning. Because of the complexity of sleep reports, your family physician may not be able to answer some of your questions regarding the results. Sleep study results are not generally discussed over the telephone because of their complex nature. Your family physician will receive a copy of the sleep report within 4 weeks. The sleep physician may recommend that you have another test in the sleep lab. If so, do not be alarmed or disappointed. Sometimes additional procedures are needed to provide more information to establish a diagnosis or evaluate a treatment

The Multiple Wakefulness Test (MWT) is another way of determining your ability to stay awake. During this test you will be asked to sit quietly in a darkened room for about 40 minutes while trying to stay awake.

OSA is characterized by repetitive episodes of upper airway obstruction that occur during sleep, usually associated with a reduction in blood oxygen saturation (or an arousal). Patients often complain of excessive daytime sleepiness or daytime fatigue. Along with the frequent episodes of obstructed breathing that occur during sleep, there may be loud snoring, morning headaches and a dry mouth upon awakening.

An oral appliance is a device which fits over the upper and lower teeth (something like a hockey mouth guard), which is used to treat obstructive sleep apnea. It is more often used to treat mild obstructive sleep apnea. The device is designed to hold the lower jaw forward during sleep, so that the throat area remains open.

You should get your family physician to refer you to the sleep laboratory. They could fax a referral to us at the clinic office fax number 613 549 1459 for the attention of Dr. M.F. Fitzpatrick or Dr. P.W. Munt.
Click here for the Sleep Referral Form to the Sleep Clinic and Laboratory, to download and print.