Sleep Studies

What are sleep studies?

A sleep study or polysomnography, is a procedure done for the diagnosis of sleep disorder. It works by measuring the biophysiological changes that occurs in the body during sleep which include the brain, eye, heart, and muscle activity. Additional monitoring includes respiratory airflow and peripheral pulse oximetry.

Indications for sleep studies?

It is indicated whenever patients complain of excessive daytime sleepiness or fatigue. Some of these disorders include narcolepsy, periodic limb movement disorder (PLMD), REM behavior disorder, parasomnias, sleep apnea and sleep related seizure disorders.

Preparation for a sleep study

A doctor usually asks a patient to keep track of sleep in a diary 1 or 2 weeks before the study.
A record of all drugs and medication that may be used by the patient, is taken and certain drugs such as sedatives will be stopped.
Drinks with caffeine must be stopped a day or two before the test.
Before going to the sleep lab make sure not to use any makeup or any oils or gels on the face and hands because test equipment will be placed on these areas for the study.
Be sure to pack overnight essentials such as comfortable clothing and a toothbrush for the stay.

What happens during the study?

Electrodes will be placed over the patients, scalp, face, chest and lower limbs. This is done by securing electrodes on the surface of these areas with non toxic pastes and glues. An additional clip electrode will be placed on the finger of the patient.These electrodes will measure:

Blood oxygen levels
Brain waves
Breathing effort and movement
Eye movement
Heart rhythms
Leg movements

The patient will then be allowed to fall asleep naturally and monitoring will commence.

What happens after the overnight study?

The electrodes will be removed with acetone. The remaining gel/paste is easily removed. The patient will be allowed to shower and change while the data is reviewed by a doctor.

Results will then be discussed with the patient.