Laboratory Sleep Study

An in-laboratory sleep study is a comprehensive overnight assessment conducted in a purpose-built sleep laboratory. It provides the most detailed picture of sleep health available, and is recommended for patients who need a broader evaluation than a home sleep study can provide.

What is an in-laboratory sleep study?

Polysomnography (PSG) is the gold standard diagnostic test for sleep disorders. Unlike a home sleep study, which focuses primarily on breathing and oxygen levels, a full laboratory study simultaneously records brain activity, eye movements, muscle tone, heart rhythm, breathing effort, oxygen saturation, and leg movements throughout the night. With complex signal additions which can include; arm movements, transcutaneous CO2 monitoring and CPAP/ ASV/ Bi-level treatment methods.

This breadth of data allows sleep physicians to diagnose a wide range of sleep conditions and to assess sleep architecture in detail. The study is conducted by a qualified sleep technologist who monitors recordings in real time and can make adjustments during the night if needed.

What does it measure?

Brain activity (EEG)

Snoring is caused by partial obstruction of the airway during sleep. While it may seem harmless, it can be a sign of obstructive sleep apnoea (OSA). Diagnostic sleep studies are available to assess the severity of snoring, and treatment options may include lifestyle changes, continuous positive airway pressure (CPAP), or other airway devices to improve airflow and sleep quality.

Muscle tone (EMG)

Detects abnormal movements and REM sleep behaviour disorder.

Breathing effort

Identifies obstructive versus central respiratory events.

Oxygen saturation

Continuous overnight pulse oximetry to identified oxygen desaturation index and burden.

Heart rhythm (ECG)

Detects cardiac arrhythmias during sleep.

Leg movements

Assesses for periodic limb movement disorder.

Body position

Identifies positional components to breathing disorders.

Camera

Identifies vocalisations, periodic movements, parasomnias and sleepwalking.

Studies and services available

The sleep laboratory at John Flynn Hospital offers a range of overnight studies, as directed by the treating Respiratory and Sleep Physician.

Diagnostic polysomnography

Full overnight study to diagnose obstructive sleep apnoea, central sleep apnoea, REM sleep behaviour disorder, periodic limb movement disorder, and other sleep conditions.

CPAP titration

Supervised overnight study to determine the optimal CPAP pressure for patients commencing CPAP therapy, or to review and adjust therapy in patients with an existing CPAP prescription.

ASV/ Bi-level titration

Supervised overnight study to determine the optimal ASV/Bi-level pressure for patients commencing nocturnal ventilation therapy, or to review and adjust therapy in patients with an existing prescription. We can also entrain supplemental oxygen therapy for those patients who require positive airway pressure and oxygen.

Transcutaneous CO₂ monitoring (TcCO₂)

Non-invasive overnight monitoring of carbon dioxide levels, used in the assessment of hypoventilation disorders including; obesity hypoventilation syndrome and neuromuscular disease where CO₂ retention during sleep is a concern.

When is a laboratory study recommended?

Many patients are well-served by a home sleep study, which is simpler, and more convenient. A laboratory study is recommended when a more detailed or supervised assessment is needed. This includes:

Suspected non-respiratory sleep disorders, such as REM sleep behaviour disorder, narcolepsy, or periodic limb movement disorder
Significant or complex medical history — including heart failure, neuromuscular disease, or severe COPD
A home sleep study result that was inconclusive or technically inadequate
Need to titrate CPAP or non-invasive ventilation therapy in a supervised setting
Suspected hypoventilation or CO₂ retention during sleep
Suspected central sleep apnoea or complex breathing patterns

The Respiratory and Sleep Physician will advise which study is most appropriate following your consultation. You can learn more about home sleep studies on the home sleep study page.

Private health insurance and costs

If you do not hold private health insurance, please contact the clinic to discuss options.

What to expect on the night

See a Respiratory and Sleep Physician first

Before a laboratory study can be booked, a consultation with a Respiratory and Sleep Physician is required. Ask your GP to provide a referral to the specialist in the first instance. The physician will assess your symptoms, confirm the indication, and determine which study is most appropriate.

Confirm your insurance

Contact your private health insurer to confirm you are covered for an in-hospital sleep study. The clinic team can assist with any questions about the booking or insurance process.

Arrive at John Flynn Hospital

Arrive at the sleep laboratory at the scheduled admission time — typically early evening (6:30pm) Bring your Medicare card, insurance details, any regular medications, and comfortable two-piece sleepwear. Please also bring a book or something to occupy your time if you do not wish to watch TV. Continue your normal routine during the day, avoiding caffeine after midday and not applying hair products or moisturiser.

Set-up by the sleep technologist

A qualified sleep technologist will attach a series of sensors to your scalp, face, chest, abdomen, and legs. This takes around 45–60 minutes and is not painful. Most patients sleep reasonably well once settled.

Sleep — monitored overnight

Sleep — monitored overnight The technologist monitors all recordings throughout the night from an adjacent room and can communicate with you if needed. You will be woken at a scheduled time in the morning.

Discharge and results

Sensors are removed and you are free to go — most patients are discharged by 7am. The overnight data is reviewed by the Respiratory and Sleep Physician, who will follow up to discuss findings, diagnosis, and any treatment recommendations.

Frequently asked questions

Can my GP refer me directly for a laboratory study?

No. A consultation with a Respiratory and Sleep Physician is required before a laboratory study can be booked. Ask your GP to refer you to the specialist in the first instance. The physician will assess your situation and arrange the appropriate study.

Do I need private health insurance?

Yes. In-laboratory sleep studies at John Flynn Hospital are provided on a no-gap basis, which requires appropriate private health insurance cover for in-hospital procedures. It is recommended you confirm your coverage with your insurer before booking. If you do not have private health insurance, please contact the clinic to discuss your options.

Will I be able to sleep with all the sensors attached?

This is the most common concern patients have. In practice, most people sleep better than they expect. The sensors are not painful, and the sleep laboratory is designed to be quiet and comfortable. Even if sleep is lighter than usual, sufficient data can generally be collected for a reliable result.

What should I bring on the night?

Bring comfortable sleepwear, any regular medications, your Medicare card, and your private health insurance details. Avoid napping during the day and limit caffeine after midday. Do not apply hair products or moisturiser on the day of the study, as these can interfere with sensor adhesion.

When will I get my results?

The overnight recording is reviewed by the Respiratory and Sleep Physician after your study. A follow-up appointment is arranged to discuss findings, diagnosis, and any treatment recommendations.

FOR GPS AND REFERRING CLINICIANS

Please refer patients to a Respiratory and Sleep Physician in the first instance — laboratory studies are booked following specialist consultation. The sleep laboratory at John Flynn Hospital offers diagnostic polysomnography (MBS 12203), CPAP titration (MBS 12204), and transcutaneous CO₂ monitoring, all on a no-gap basis for patients with appropriate private health insurance. For patients without private health insurance or where a home study is appropriate, please see the home sleep study service.

Ready to get started?

Ask your GP for a referral to a Respiratory and Sleep Physician.
The specialist will assess your symptoms and arrange the appropriate study.