Sleep Studies

Sleep studies (also called polysomnograms) are frequently used to evaluate patients while they are sleeping.  This test is extremely valuable for diagnosing and treating many sleep disorders, including sleep breathing disorders such as sleep apnea, movement disorders, and neurologic disorders.  Sleep studies are ordered by sleep physicians in the Pulmonary Medicine Associates Sleep Disorder Center and are performed in the sleep laboratory. 

Our sleep center provides comfortable, private rooms for your sleep study.  While you sleep, we monitor your heart rate, body movements, brain activity, breathing, eye movements, and other physiologic functions.  The procedure is neither painful nor invasive and does not prevent getting a regular night's sleep. Shower facilities are also available if you need to go straight to work from the Sleep Center.

Patients come to the sleep center at 7:30 or 9:00 p.m. on the appointed day.  There they meet with a sleep technologist, who will explain and perform the sleep study.  Electrodes are applied to the scalp, sides of the head, on the chin, chest and legs.  A sensor is placed by the nose and mouth for measurement of airflow.  Belts are place around the rib cage and abdomen for measurement of breathing movements.  A clip is place on a finger to measure blood oxygen levels. All patients are videotaped as well. There are no needles and no pain.  The electrodes are connected to a box by the bedside for relaying the signals to the central control room.  Your sleep technologist will show you how to easily disconnect the equipment to use the restroom at any time.  Sleep studies are usually finished around 6:30 to 7:00 in the morning.  However, if an earlier or later wake-up time is needed, the patient just needs to let the technologist know.  Sleep studies may also be done during the daytime for patients who normally sleep during that time.

In the central control room, the technologist monitors the patient's sleep and general condition.  Any problems with the study may be easily dealt with.  Patients may easily call the technologist if there is a problem as well.  All of our technologists are highly trained and certified in polysomnography.  Many of them are Registered by the Board of Polysomnographic Technologists.

Once the sleep study is completed, it is analyzed and scored by a scoring technologist and is interpreted by a sleep specialist. This entire process takes just a few days.  Sleep studies are generally very easy to tolerate and comfortable for the patient. There are many things the technologist can do to help make the sleep study more comfortable for the patient and should be asked for anything needed at any time.

There are a few thing patients coming in for a sleep study should know.  A list of instructions should have been provided in the New-Patient Packet. This information can also be found here.  Sleep Study Instructions

CPAP Titration Sleep Studies

For some patients who are diagnosed with sleep apnea during the diagnostic sleep study, a trial of CPAP may be prescribed.  This entails a sleep study wearing a small mask that delivers a pressure from a machine.  The pressure splints the airway open.  Everyone requires a different pressure and some people require different types of CPAP.  This is called a CPAP titration study and it is started with CPAP on the lowest possible pressure.  The pressure is adjusted until no more apneas are seen.  All of the same sensors are used during a CPAP titration sleep study.  Whenever possible, diagnosis and CPAP titration are performed in the same night.  Certain criteria must be met to do this but every effort is made to accomplish it.

Multiple Sleep Latency Test (MSLT)

When certain disorders are suspected by the physician a special sleep study called a Multiple Sleep Latency Test (MSLT) may be ordered.  This test entails an overnight sleep study followed by a series of naps the next day.  The naps are taken every two hours.  This test is used to assess sleepiness during the day, sleep-wake cycle disorders, and how well medications work.  Depending on what is seen in the naps, four or five naps are taken.  Patients are usually done with this test around 3:00 p.m.  Patients coming in for this test should bring meals with them.  A refrigerator, freezer, microwave and toaster oven are available for patient use.  Other instructions are provided with the new patient packet or when the test is scheduled.  They can also be found at the following link.  MSLT Instructions

Maintenance of Wakefulness Test (MWT)

The maintenance of wakefulness test (MWT) is used to assess the patient's ability to stay awake during the day.  The patient sits in a comfortable chair in a dimly lit room and tries to stay awake for a certain amount of time.  This is done every two hours a total of four times  This test is mainly done to assess the efficacy of treatment (CPAP or medications) especially in patients who perform jobs that require them to be highly alert.

Apnea Link (At Home Sleep Apnea Screening Studies)

This is a test that screens patients for sleep apnea.  The test entails wearing a small device on a belt around the patient's waist as well as two other sensors: one that is worn by the nose and mouth (similar to an oxygen cannula) and a clip that is worn on a finger that measures blood oxygen levels.  The device is picked up at the sleep center by the patient where a technologist will give instructions for applying and using it.  The instructions can also be downloaded here. Apnea Link Instructions  The apnea Link does not diagnose sleep apnea, it tells the doctor if a sleep study should be done.

Overnight Oximetry

Overnight oximetry measures the patient's blood oxygen level throughout the night while the patient is asleep.  This test entails wearing a small device on the wrist (about the size of a wrist watch) with a clip on a finger.  The oximeter is picked up at the Sleep Center or at our Pulmonary Office by the patient.  A technologist or medical assistant will provide the device as well as instructions for use.  Instructions can also be downloaded here. Overnight Oximetry Instructions  The overnight oximetry may be used to assess the patient's blood oxygen levels to determine if oxygen therapy is needed,  screen for sleep apnea, see if prescribed treatment is working adequately. 

Pulmonary Function Testing (PFT)

Pulmonary function testing is a non-invasive diagnostic procedure which is done to assess the functional status of the patient's lungs.  Pulmonary function testing is used for the following reasons: screening for the presence of obstructive and resistive diseases, evaluating the patient prior to surgery, documenting the progression of pulmonary disease, and documenting the effectiveness of therapeutic intervention.  Pre-test instructions and more information on this test can be found on the following link PFT Instructions.

A nebulizer is a device used to administer medication to people in the form of a mist inhaled into the lungs. It is commonly used in treating cystic fibrosis, asthma and other respiratory diseases .