What to expect during your sleep study
The all-night sleep study (also known as Polysomnography) is the most common sleep study, and is performed to measure a patient’s normal sleep. This test is used for diagnosing and treating many sleep disorders, including sleep related breathing disorders, sleep related movement disorders, and neurological disorders. A physicians order is required for a sleep study; therefore patients must visit their physician or one of our Board Certified Sleep Medicine Physicians to discuss their sleep problems prior to testing.
All sleep studies are typically performed as an outpatient procedure that take place from approximately 8:30 pm until 5:30 am – 6:00 am the next day. Also, depending on the test, you may be requested by your Sleep Specialist to stay the next day for nap studies as well. Prior to testing, patients are recommended to contact their medical insurance company to have their test pre-certified or approved. Our sleep lab facility or hospital will bill the patient for the sleep test procedure. The test interpretation will be prepared by a sleep specialist, who will bill the patient separately for their interpretation services. Generally, all insurance carriers cover these charges, but some policies have exclusions for sleep disorders. Questions regarding insurance coverage need to be answered by the insurance provider and should be done prior to completing the testing.
On the date of the test, patients are asked to take a few measures to help insure the quality of their test. Patients should avoid alcoholic beverages and stimulants such as caffeine on the date of their test. Various electrode and sensor applications will be applied to the patient’s skin and scalp. It is crucial for the patient to shower on the date of the test to ensure their hair and skin is free of oils and lotions that may make these applications difficult. They should also avoid applying makeup or fingernail polish before the test, as these will interfere with the testing devices ability to record signals. Unless otherwise instructed by their physician, patients should continue to take whatever medications their physician has prescribed for them.
Patients should pack a few things for their test, such as:
- A list of all medications that the patient is currently taking
- Medications that they will need during the study, including enough supplemental oxygen to sustain them for the drive to and from the sleep center
- Comfortable nightclothes such as pajamas, robe, slippers, etc.
- Toiletry items such as toothbrush, toothpaste, etc.
- The completed Sleep Questionnaire that will be mailed to the patient upon scheduling the test
- Health Insurance Card and any physician referral forms
- State Identification Card (driver’s license, etc.)
- Favorite bedtime snack, drink, etc.
- Favorite pillow if they have a preference.
- Reading materials, cell phones, iPods/iphone/itouch/laptops are permitted but their use will be limited once the “sleep time” has arrived. They can be turned on after the completion of the study in the morning.
- Reading materials, card games, puzzle books are permitted but again their use will be limited.
- Children may want to bring their favorite toy (or a few) to play with during the few minutes before the measurements begin. They might also like to bring the toy they sleep with.
- Patients that are unable to / or choose not to drive themselves to their test must arrange for their own transportation from the facility between 5:30-6:00am on the morning after the test.
Our sleep centers are located in local hospital and clinics. They have a hotel look and feel to them. The sleeping rooms are comfortable, hotel-like rooms with queen or full (not hospital) beds. Each room has a television. Private washrooms and shower facilities are available. Convenient parking is also available at each of our sleep centers. The rooms are secure and the Sleep Technician will be awake and monitoring the patient at all times during the test.
Patients are instructed to arrive for their test at 8:30 p.m. on the appointed day, unless otherwise instructed by the scheduling staff. There they meet with a sleep technologist, who will escort them to their bedroom. After arriving and getting acquainted with the technologist and the facility, the sleep technician will ask the patient to complete some bedtime questionnaires and change into their pajamas or whatever they are comfortable wearing to sleep ( i.e. a loose-fitting T-shirt and shorts). The technician will then spend about 30-45 minutes preparing the patient for the study and explaining the procedure.
During the test preparation process, the skin will be prepped using a gentle scrub to rid the dead skin, excess oil, and dirt. This step enables good contact and signal quality and is not painful. Electrodes are applied to predetermined locations on the patients scalp, face, chest, and legs. This allows us to measure brain waves, heart rate, and body movements. A conductive paste will be used to apply each electrode. The paste keeps the wires in place as well as to better conduct the electrical waves of your body. After the study is completed, the paste will wash out with shampoo. Some of the wires on the face will be taped in place, and are easily removed in the morning. A sensor is placed by the nose and mouth for measurement of breathing airflow. Belts are placed around the chest and abdomen for measurement of breathing movements. A clip is placed on a finger for measurement of blood oxygen levels.
All the sensors and electrodes are connected to a single “head box” which transmits the test signals to the computer that the technologist monitors from the control room. The technologist monitors the patient's sleep and general condition. Patients may easily call the technologist for any need including washroom breaks. For washroom breaks, the technician easily disconnects one main cable from the head box and the patient is free to use the washroom on their own.
Before the study begins, the technician will have the patient go through calibrations of the equipment. These are little movements that are necessary to make sure all the signals are being transmitted properly and that there are no broken wires. The technologist will ask the patient to perform the following commands before the study begins:
- Look straight ahead with eyes open
- Look straight ahead with eyes closed
- Look up with eyes closed
- Look down with eyes closed
- Look left with eyes closed
- Look right with eyes closed
- Blink 5 times
- Breathe through nose only
- Hold breath for 10 seconds
- Breathe through mouth only
- Move legs
- Bite down and grind teeth
Once the technologist confirms that all the diagnostic equipment is calibrated and working properly, the study will begin. This is also known as the “Lights Out” time of the study. The technician will turn off the lights and the television at this time.
During a diagnostic sleep study, the patient will be attached to the above mentioned sensors and electrodes. The patient’s normal stages and breathing will be monitored. The patient is free to sleep in any position that is comfortable. To ensure that a complete assessment of the patients sleep is achieved, the technologist may ask the patient to sleep on their back for a portion of the study.
For some patients who have sleep apnea, the effects of continuous positive airway pressure therapy (also known as CPAP) are evaluated. Usually these are patients who have had a previous sleep study to diagnose the condition; although patients with severe sleep apnea may be offered CPAP half way through the initial diagnostic sleep study (also known as a Split-Night Test). During the therapeutic study with CPAP, everything is done as for a diagnostic study. In addition, a mask is fit around the nose or around the nose and mouth. During sleep, the technician will attempt to find a pressure level that holds the airway open. This allows the patient to breathe properly due to the pressure preventing the airway from collapsing.
The all-night sleep study requires 6 hours of recording time and usually ends at 5:00 -5:30 am. The technician will remove all the sensors and electrodes when the patient wakes up. The patient will be asked to complete some morning questionnaires and are typically free to leave the sleep lab by 6:00 am.
Some patients many need to complete a Multiple Sleep Latency Test (also known as MSLT), which is used to evaluate and diagnose daytime sleepiness and/or narcolepsy. An MSLT is typically performed in the daytime immediately following an all-night sleep study. During the MSLT, the patient is monitored every 1.5 to 2 hours during 25-30 minute naps. This is done 4 to 5 times throughout the day. Breakfast and/or lunch will be provided for MSLT patients.
The technician will not be able to give the patient any results immediately following the study. The data collected be will scored by a technologist. Once scored, one of our board certified sleep specialist physicians will interpret the findings and prepare a multi-page summary of their impressions and recommendations. This entire process usually takes 5 business days. The interpretation results are sent to the physician who ordered the sleep study. The patient will be able to follow up with the physician who ordered the study in less than a week.