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Polysomnography (PSG) is a sleep test to learn if you have a sleep-related breathing disorder (SRBD), such as obstructive sleep apnea.


The week before your procedure:

  • Write down the correct date, time, and location of your procedure.
  • You or a close family member will be asked to sign a legal document called a consent form. It gives caregivers permission to do the procedure or surgery. It also explains the problems that may happen, and your choices. Make sure all your questions are answered before you sign this form.

The day of your procedure:

Healthcare providers will clean your skin to put on the electrodes. Any of the following monitors may be used for your PSG test:

  • ECG: This test, also called an EKG, helps healthcare providers look for any problems in your heart. If you have an SRBD, your heartbeat may change during sleep because it does not get enough oxygen. Sticky pads are placed on your chest, arms, and legs. Each sticky pad has a wire that is hooked to a machine or monitor. Electrical activity in your heart muscle is recorded.
  • EEG: This test is also called an electroencephalogram. This test is done to see how your brain is working during the different stages of sleep. Electrodes will be put on your head. Each has a wire that is hooked to a machine. This machine prints a paper tracing of brain wave activity from different parts of your brain.
  • EMG: This test, also called electromyography, measures the electrical activity of your muscles. EMGs are used to check your leg and facial movements while you sleep.
  • EOG: This test, also called electrooculogram, measures your eye movements while you sleep. Electrodes are be placed near your right eyebrow and under your left eye.
  • Plethysmogram: This test monitors your chest and abdominal movement. Elastic belts are placed around your chest and abdomen to see how deep you breathe. This test also tells your healthcare provider how many breaths you take per minute and if you stop breathing.
  • A pulse oximeter is a device that measures the amount of oxygen in your blood. A cord with a clip or sticky strip is placed on your finger, ear, or toe. The other end of the cord is hooked to a machine.
  • Recordings: Recordings may be done while you sleep by a video, microphone, or both. This is done to hear how loud your snoring is and to see how you sleep. If a microphone is used, an electrode may be placed on your throat or neck.
  • Thermistor: This test uses a sensor to measure your nasal pressure. The thermistor will tell your healthcare provider how much airflow you have through your nose and mouth while asleep.


  • Your hospital PSG test will be done in a sleep room that looks like a bedroom. Healthcare providers will monitor your sleep for the whole test. When the test is over, the electrodes will be taken off. You may be able to take a shower if you choose. You will then be able to go home. The results of your PSG test will be given to you at your follow-up visit.
  • If your PSG test is done in your home, you may need electrodes put on at the hospital first. Healthcare providers will tell you how to set up your monitor. They may also tell you what position to sleep in. If someone will be helping you at home, bring them with you so they understand the instructions.


  • You cannot make it to your PSG test.
  • You get sick or have a fever.
  • You have questions or concerns about your PSG test.


Having an SRBD may make it hard to do normal activities such as work and school. SRBDs cause daytime sleepiness which may lead to car accidents or other injury. SRBDs that are not treated may cause more severe health problems. Untreated SRBDs may cause high blood pressure, heart disease, and stroke. You may need two or more PSG tests while healthcare providers treat your breathing problem.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Learn more about Polysomnography (Precare)

Associated drugs

IBM Watson Micromedex