What Is a Sleep Study (Polysomnography), and How Should You Prepare for It?
1. What Is Polysomnography?
Polysomnography is a medical term for a method of recording various physiological activities that occur while you sleep. These activities are recorded using electrodes, and the signals are transmitted to a computer. The doctor then reviews the recordings and informs you of the results.
2. What Physiological Activities Are Recorded During Polysomnography?
- Brain activity (electrodes placed on the scalp)
- Eye movements (electrodes placed near the eyes)
- Chin muscle tone (electrodes placed near the chin)
- Heart rate (electrodes placed on the chest)
- Leg movements (electrodes placed on the legs)
- Airflow (sensors placed near the nose and mouth)
- Respiratory movements (two elastic bands placed around the chest and abdomen)
- Oxygen saturation (a small sensor attached to the finger or earlobe)
- Audio recording and digital video recording
3. Polysomnography Is the Best Method for Confirming the Diagnosis of Various Sleep Disorders, Such As:
- Obstructive sleep apnea
- Central sleep apnea
- Narcolepsy
- Insomnia
- Restless legs syndrome
- Periodic limb movements
- Sleep-related disorders
4. Why Is It Necessary to Measure Physiological Activities During Sleep?
While you are asleep, your body's activities differ from those when you are awake. Sleep disorders such as snoring, sleep apnea, and insomnia can affect daytime activities, cause excessive daytime sleepiness, and potentially lead to serious health problems. Because physiological activities need to be monitored during sleep, you will stay overnight in the hospital's sleep study room during polysomnography.
By recording physiological activities during sleep, the doctor can identify the type of sleep disorder you may have and develop an appropriate treatment plan.
5. Frequently Asked Questions
Will the electrodes affect me during the sleep study?
No. Polysomnography is a non-invasive and painless test. The electrodes are attached to your scalp and do not cause pain or deliver electric shocks. After the sleep study is completed, the electrodes can be gently removed.
Will the electrodes interfere with my sleep?
The equipment is designed to record physiological activities during sleep, so it is designed to allow you to relax and prepare for sleep. The polysomnography room at University Medical Center Ho Chi Minh City is designed to provide a comfortable and familiar environment to help you sleep more easily. The room also has amenities such as air conditioning, a resting bed for family members, a shower, and a toilet to help you feel at home.
Can I move around, such as going to the bathroom, after the electrodes are attached?
The electrodes and cables do not prevent you from moving around, but you should limit unnecessary movement. You will wear a signal transmitter that transmits the recorded signals to a computer. If you need to use the bathroom, the attending nurse will disconnect the cable between the transmitter and the computer so that you can move around.
What should I prepare on the day of the sleep study?
- Complete the questionnaire and bring your prescriptions, medical orders, and instructions from your doctor. You may bring your own pillow and blanket if you would feel more comfortable using familiar items.
- Wear comfortable clothing suitable for sleeping.
- Bring personal hygiene items and clothes to change into the following morning.
- Do not drink alcohol, beer, or stimulants such as tea or coffee on the day of the study.
- Limit daytime naps.
- Eat normally.
- Wash your hair thoroughly before the study.
- Bring any medications you are currently taking and your prescriptions.
- Bring your polysomnography payment receipt.
- Bring any test results from the past 6 months, if available.
- Bring a book if you usually read before going to bed.
- If you need a light meal or snack before bedtime, inform the staff in advance and bring it with you.
Study time: 8:00 p.m. to 6:00 a.m. the following morning (or according to your usual sleep schedule – please discuss this in advance with the secretary, attending nurse, or doctor).
The information above is for reference purposes only and is not intended as medical advice. Please contact your doctor for detailed medical consultation.