In-Laboratory Polysomnography
What Is In-Laboratory Polysomnography?
In-laboratory polysomnography is a comprehensive sleep study conducted overnight in a clinical sleep lab to diagnose sleep disorders. This test records various body functions during sleep, including brain activity, eye movements, heart rate, breathing patterns, blood oxygen levels, and limb movements. It is considered the gold standard for evaluating conditions such as obstructive sleep apnoea, narcolepsy, periodic limb movement disorder, and parasomnias (like sleepwalking or night terrors).
When Is In-Laboratory Polysomnography Recommended?
Polysomnography is typically recommended when a patient presents symptoms that suggest a sleep disorder. Common indications include:
- Loud, chronic snoring and observed pauses in breathing during sleep
- Excessive daytime sleepiness despite adequate rest
- Frequent nighttime awakenings or restless sleep
- Unusual behaviours during sleep, such as talking or walking
- Leg twitching or jerking at night
- Diagnosing narcolepsy or REM sleep behaviour disorder
- Evaluating the effectiveness of CPAP or other therapies
How Is In-Laboratory Polysomnography Performed?
The patient arrives at the sleep centre in the evening and stays overnight in a private, comfortable room. A sleep technician attaches non-invasive sensors to the patient’s scalp, face, chest, limbs, and finger using adhesive or belts. These sensors monitor brain waves, oxygen levels, breathing effort, eye and limb movements, and heart activity while the patient sleeps. A video camera may also record movements for further assessment. The study typically lasts for 6–8 hours.
What to Expect During Recovery After Polysomnography?
No recovery period is needed, as polysomnography is a non-invasive and painless test. Patients can usually return to their normal routine the following day. If sleep was disrupted due to the unfamiliar environment, a repeat test may be considered. Results are interpreted by a sleep physician and discussed during a follow-up appointment.
What Are the Risks of In-Laboratory Polysomnography?
Polysomnography is very safe, but a few minor inconveniences may occur:
- Mild skin irritation from adhesives or sensors
- Discomfort or trouble sleeping due to unfamiliar setting
- Anxiety about being observed during sleep
- Rare dislodgement of sensors that may affect results
What Are the Benefits of In-Laboratory Polysomnography?
The test offers detailed insights and accurate diagnosis for better treatment:
- Precise detection of complex sleep disorders
- Helps guide therapy such as CPAP or medication
- Identifies multiple sleep issues simultaneously
- Improves long-term health by addressing untreated sleep problems
- Provides baseline data for future comparison and care planning