Polysomnography is an exam that serves to analyze the quality of sleep and diagnose sleep-related illnesses and can be indicated for people of any age. During the polysomnography exam, the patient sleeps with electrodes attached to the body that allow the simultaneous recording of various parameters such as brain activity, eye movement, muscle activities, breathing, among others.
The main indications for the exam include the investigation and evaluation of disorders such as:
- Obstructive sleep apnea. Learn more about what causes and how to identify this disease; Excessive snoring; Insomnia; Excessive drowsiness; Sleepwalking; Narcolepsy. Understand what narcolepsy is and how to treat it; Restless legs syndrome; Arrhythmias that occur during sleep; Night terror; Bruxism, which is the habit of grinding your teeth.
Polysomnography is usually performed during an overnight stay in the hospital, to allow monitoring. In some cases, home polysomnography can be performed with a portable device, which, although not as complete as the one performed in the hospital, can be useful in cases indicated by the doctor.
Polysomnography is performed in specialized sleep or neurology clinics, and can be done free of charge by SUS, as long as duly indicated by the doctor. It can also be covered by some health plans, or it can be done privately, and its price costs, on average, from 800 to 2000 reais, depending on the place where it is made and the parameters evaluated during the exam.
How it is done
To perform the polysomnography, electrodes are attached to the patient's scalp and body, in addition to a sensor on the finger, so that, during sleep, the parameters that allow detection of changes suspected by the doctor are analyzed.
Thus, during polysomnography several assessments are made which include:
- Electroencephalogram (EEG): serves to record brain activity during sleep; Electro-oculogram (EOG): allows you to identify which phases of sleep and when they start; Electro-myogram: records the movement of muscles during the night; Airflow from the mouth and nose: analyzes breathing; Respiratory effort: from the chest and abdomen; Electrocardiogram: checks the rhythm of the heart's functioning; Oximetry: analyzes the rate of oxygen in the blood; Snoring sensor: registers the snoring intensity. Lower limb movement sensor, among others.
Polysomnography is a non-invasive and painless exam, so it does not usually cause side effects, and the most common is skin irritation caused by the glue used to fix the electrodes on the skin.
The test should not be done when the patient has the flu, cough, cold, fever, or other problems that may interfere with sleep and the test result.
How preparation is done
To perform the polysomnography, it is recommended to avoid the consumption of coffee, energy drinks or alcoholic drinks 24 hours before the exam, to avoid using creams and gel that make it difficult to fix the electrodes and not to paint the nails with dark enamel.
In addition, it is advised to maintain the use of usual remedies before and during the exam. A tip to facilitate sleep during the exam is to bring pajamas and comfortable clothes, in addition to your own pillow or personal items.
