What is the Maintenance of Wakefulness Test (MWT)?
The Maintenance of Wakefulness Test (MWT) is a specialised diagnostic sleep study designed to assess a person’s ability to stay awake in a quiet and dimly lit environment. This test is commonly used to evaluate excessive daytime sleepiness and determine whether an individual can remain alert during situations that require sustained attention.
What Does the MWT Measure?
The MWT measures an individual’s ability to resist sleep under controlled conditions. It provides valuable information about daytime alertness and is particularly useful for assessing conditions such as narcolepsy, sleep apnoea, and other disorders that cause excessive daytime drowsiness. The results help guide treatment recommendations and decisions regarding fitness for safety-sensitive tasks, such as driving or operating heavy machinery.
Who Needs an MWT?
A doctor may recommend an MWT for individuals who:
- Experience excessive daytime sleepiness that affects daily activities or work performance
- Require certification for employment in safety-sensitive roles, such as commercial drivers, pilots, or machinery operators
- Have been diagnosed with a sleep disorder and need assessment of treatment effectiveness
- Need documentation of wakefulness ability for legal or occupational requirements
What is the Process of an MWT?
The test is conducted in a sleep laboratory and consists of four to five testing sessions spaced two hours apart throughout the day. During each session:
- The patient sits in a comfortable chair in a dimly lit, quiet room.
- Sensors are placed on the head and face to monitor brain activity, eye movements, and muscle tone.
- The patient is instructed to remain still and try to stay awake without stimulation.
- The session lasts up to 40 minutes, or until sleep occurs.
- Between sessions, the patient remains awake in a controlled environment.
How to Prepare for the Test
To ensure accurate results, patients should follow these guidelines before their MWT:
- Follow Normal Sleep Patterns – Maintain a consistent sleep schedule in the days leading up to the test.
- Avoid Caffeine and Stimulants – Refrain from consuming caffeine, nicotine, or stimulant medications before the test unless advised otherwise by a doctor.
- Take Prescribed Medications as Directed – Inform the sleep specialist of any medications being taken, as they may affect test results.
- Bring Comfortable Clothing and Reading Materials – The test involves waiting periods between sessions, so patients may bring something to read or do while staying awake.
- Eat Regular Meals – Have a light meal before the test and avoid heavy meals that may cause drowsiness.
Book an MWT at Manse Medical
At Manse Medical, our experienced team provides comprehensive respiratory and sleep assessments, including the MWT. If you have concerns about excessive daytime sleepiness or need an MWT for work or medical reasons, contact us today to schedule an appointment.