What is a sleep study ?
A sleep study, formally known as a polysomnogram, is a diagnostic test that tracks and records how multiple body systems work while you’re asleep. It tracks the activities of your heart, brain, respiratory system, eye and leg movements, giving healthcare providers a comprehensive view of the quality of your sleep.
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Polysomnography monitors your sleep stages and cycles. It can identify if or when your sleep patterns are disrupted and why.
How does a sleep study work ?
A sleep study involves the following sensors and monitoring methods:
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Electroencephalography (EEG) - detect and record the electrical activity of your brain
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Electrocardiography (EKG or ECG)- record electrical activity of your heart
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Electro-oculography (EOG) - detect eye movements or activities
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Breathing sensors - detect air movement through your mouth and nose
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Respiratory inductive plethysmography (RIP) belt - detects the expansion of your torso, especially around your chest and belly, when you breathe.
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Pulse oximeter - reads your pulse and the level of oxygen in your blood
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Video and audio monitoring
When is a sleep study necessary ?
Conditions that a sleep study can diagnose include:
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Sleep apnea (obstructive and central).
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Periodic limb movement disorder (including restless legs syndrome).
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Night terrors (also known as sleep terrors)
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Sleepwalking or other sleep behavior-related disorders
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Other types of parasomnias and disruptive sleep disorders
When is a sleep study performed ?
Most sleep studies take place during your normal sleeping hours. Because most people sleep during nighttime hours, facilities that perform sleep studies (known as sleep labs) schedule most people for overnight sleep studies.
What should I expect on the date of a sleep study ?
On the day of your sleep study, you should mostly go about your usual routine. But there are also a few things you should keep in mind:
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Avoid caffeine and alcohol for at least eight hours before your sleep study.
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Don’t nap. Taking a nap can make it harder for you to fall asleep during your sleep study.
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Stick to your routine as best you can. The more naturally you sleep during a sleep study, the more accurately your doctor can interpret the results, diagnose any condition(s) you have and treat you accordingly.
What should I expect after a sleep study ?
In the morning, you’ll wake up and sleep lab staff will help disconnect and remove all the sensors. After that, you can change into your clothes for the day and leave the sleep lab.