Sleep Laboratory (Sleep Tests)

What is a Sleep Lab?

The sleep laboratory is a centre where all the sleep related data of the patient presenting with sleep disorder are recorded on the computer for later analysis. However, this place looks like a comfortable hotel room rather than a laboratory.

In the sleep laboratory, it is determined whether the person has a disease by monitoring the entire sleep flow of the individual throughout the night through both the device and the camera until they wake up, and by looking at their behaviour during sleep. During this determination, the patient stays in this special room in the hospital and while he is asleep at night, his sleep is recorded by being subjected to a sleep test called “polysomnography” (PSG).

With the device used in the sleep test, the person’s brain activities/waves, leg movements, lying position, breathing, snoring, airflow from the mouth and nose, heart rate/rhythm and oxygen levels are detected during sleep. During this test, various cables are connected to the body and these cables are attached to a computer. This starts the monitoring process.

A sleep laboratory should be created with the sensitivity of a home environment, and the comfort of the patient should be ensured. The room where the patient will stay all night should be quiet and large enough, the toilet and the bathroom should be located in the room. In addition, the technical observation room and the patient sleep room, where technicians examine the patient’s sleep pattern and examinations, are located close to each other so that the patient can be assisted when needed.

In our Moodist Hospital Sleep Laboratory unit, our specialist physicians talk to the person and their relatives about sleep complaints and the problems they experience, and make the necessary examinations.

When Should You Apply to the Sleep Lab?

• If you suffer from insomnia, that is, if you cannot sleep at night,
• If you have the complaint of not being able to fall asleep and staying asleep, waking up frequently at night,
• If you have excessive daytime sleepiness / falling asleep during the day, falling asleep even while sitting, or sleeping at inappropriate times (speaking, driving, etc.)
• If you oversleep and have trouble getting out of bed in the morning,
• If you have a noisy snoring problem,
• If you are experiencing shortness of breath, suggesting a sleep disorder called Sleep Apnea,
• If there are sudden abnormal behaviours and perceptions that we call sleep terrors or night terrors that occur during falling asleep, during sleep, during various stages of sleep and when waking up. If there is shouting, fear, rapid breathing, sweating, if you experience involuntary and unconscious muscle movement attacks,
• If you are having bad dreams. If you have nightmares and abnormal behaviours or movements during sleep, known as parasomnia, such as bedwetting, talking, sleepwalking,
• If you have repetitive leg movements during sleep. If you have complaints that suggest restless legs syndrome, which manifests itself as an inexplicable discomfort in the legs during sleep, falling asleep or waking up. In this sleep disorder, which is described with symptoms such as itching in the legs, a chill coming from the inside of the legs, tingling or burning, if there is a constant desire to move the leg,
• If eating while asleep behaviour is observed

You can get support from the Moodist Psychiatry and Neurology Hospital Sleep Laboratory.

In addition, we can use sleep testing to detect or evaluate seizures that may occur during sleep in patients with suspected seizures.

What Happens If Sleep Disorders Are Not Treated?

Untreated sleep disorders make daily life increasingly difficult and can lead to many diseases that negatively affect the quality of life, such as disruption of social life, morning fatigue, morning headache, poor concentration, forgetfulness, failure at work, increase in traffic accidents, heart problems, hypertension, nervousness, heartburn, gastroesophageal and laryngopharyngeal reflux, stomach and intestinal diseases, obesity, depression, sexual reluctance, blood disorders, urinary problems at night.

After diagnosing sleep disorders with sleep laboratory studies, the treatment method is selected according to the severity and cause of the problem.

Tests Applied in the Scope of Sleep Laboratory

In the sleep laboratory, a test method called “polysomnography” (PSG) is applied to patients. With polysomnography (PSG), the normal and abnormal situations experienced by the patient during sleep are recorded. During a sleep test;

• Air flow from mouth and nose
• Chest and abdominal movements while breathing
• Respiratory arrest and rate during sleep
• Blood pressure
• EKG activity (heart electro)
• Jaw muscle tension electro
• Blood oxygen levels
• Brain waves
• Eye movements
• Movement changes in muscles and legs
• Electrical activity of muscles
• Body position is recorded

Polysomnography Sleep Test

Information on the changes between normal sleep and sleep based on certain diseases is determined by the reports obtained as a result of the examinations made in sleep laboratories. Polysomnographic recordings in the sleep laboratory provide the most basic data about sleep. Records can be made in many dimensions during polysomnographic examinations;

• EEG (brain electrode); By means of electroencephalograph, electroencephalographic recordings are made throughout the night’s sleep to determine the sleep-wake periods and sleep stages of the person.
• EOG (eye movement electrode); Eye movements can be determined by electrooculography.
• EMG; The electromyograph, on the other hand, allows electromyographic recordings of the muscles. The periods when the muscles are contracted or relaxed are determined.
• Jaw EMG (jaw muscle tension electromyography)
• With the lying position recordings, changes in sleep are recorded in supine or other positions, chest and abdominal movements are monitored while breathing.
• EKG (radiography of the heart); It is used to reach findings such as heart rhythm and heart rate.
• Blood oxygen level measurement with pulse oximeter, (Oxygen saturation circulating in the blood can be measured during sleep. It provides access to information such as the periods when oxygen decreases and the number, duration and depth of these periods).
• With the measurement of the air flow entering the nose while inhaling, the depth and order of the breathing are followed and the breathing stops are determined.
• Recordings of snoring,
• Leg EMG (leg muscle contraction electromyography); Many more parameters such as leg movements are monitored and evaluated.

The records taken using all these test methods are then examined and various inferences are made. First of all, the patient’s sleep structure is evaluated. Sleep stages and architecture are created. Considering the amount of oxygen the patient receives, some ideas about the body can be obtained. Data such as the breathing level of the person and the amount of oxygen in the blood can be revealed within the framework of this system.

Apart from this, it is also possible to set a course for the patient’s health by monitoring factors such as heart rhythm and leg movements during sleep as a result of the ECG. By comparing these graphs, it is possible to learn what causes the discomfort. For example, at a time when the person has trouble breathing, the heart rate can be examined to get an idea about the onset or course of some disorders.

With all these results obtained, the sleep disorder experienced by the patient is diagnosed and appropriate treatment planning is made.

Application Processes of Sleep Tests

Testing at the Sleep Centre:

• The most common type of sleep testing is done at a private sleep centre. Our sleep laboratory works with an appointment system.
• Normal sleep testing is usually done during the night. You must come to our centre 2 hours before the appointment.
• They should avoid alcohol, sleeping pills, coffee and carbonated drinks on the day of the sleep test. Sleep testing is a completely natural procedure. In other words, no local anaesthetic drug etc. is applied to the patient. It is aimed that the patient falls asleep spontaneously.
• After our sleep technician introduces the room and the procedure to our patient, who is taken to the sleeping room during the night test hour, the assembly process is applied. Electrodes are attached to the scalp, outer edge of the eyelids, chin, and chest on your head. In this way, brain waves and heartbeats are recorded during sleep. By attaching sensors to the fingertip, the amount of oxygen in the blood is recorded.
• After the assembly process is finished, our sleep technician informs our patient about the test. After checking the connections, he completes the calibration of the device. He records the signals from the electrodes during wakefulness and sleep.
• Patient’s brain electro (EEG), eye movement electrode (EOG), chin muscle tension electro (chin EMG), lying position recordings, airflow from the nose while breathing, chest and abdominal movements during breathing, blood oxygen level, heart graph (EKG), leg muscle contractions electro (leg EMG) are recorded.
• After the morning sleep test process is completed, a brief information is given to the patient by the technician, and the discharge procedures are completed.
• These records are then examined in detail, and first of all, the patient’s sleep structure and sleep stages are evaluated. By examining the breathing during sleep, it is checked whether there are abnormalities in the breathing process of the patient (such as lightening or stopping of breathing) In addition, the developing oxygen level changes, wakefulness reactions, heart rate changes, leg movements during sleep are detected and marked one by one.
• In the next process, it is revealed that whether the patient has a sleep-related or sleep-related illness, and if so, its severity by transferring all these processed data to the computer and reporting sleep quality, adequacy, whether it is divided by periods of wakefulness, whether there are breathing interruptions or reductions in sleep, if any, their frequency, duration, which sleep position is evident, which stage of sleep is evident, duration and depth of low blood oxygen level that occurs during this time, the relationship of changes in heartbeats with sleep stage and abnormal respiratory events, presence of leg movements during sleep, frequency if any.
• Our patient is informed to receive the sleep test report after the council.
• Patients diagnosed with “Severe Sleep Apnea Syndrome” in the sleep laboratory are retested for a second night of CPAP/BIPAP titration.

Home Sleep Test

A sleep test can also be done at home instead of in a sleep laboratory. Portable sleep devices are used to help diagnose Sleep Apnea. A trained sleep technician will come to your home to install the device. After the recording is completed in the morning, the device connections are disconnected and sleep analyses are performed at the centre.

Portable device application conditions;

• Under the supervision of a sleep specialist or an experienced sleep technician,
• If your doctor thinks you have obstructive sleep apnea,
• If you do not have a condition suggestive of other sleep disorders,
• Unless there are other serious medical conditions such as heart disease or lung disease.

In cases where these conditions are met a home sleep test is planned. No sleeping pills are taken on the day of the sleep test, and alcohol or caffeinated beverages are strongly discouraged before the test.

What to Do Before Taking the Sleep Test

There are a number of things to do before taking a sleep test. If we briefly list them;

• When coming to the sleep laboratory, patients should prepare as if they were going to the hotel and arrive a few hours before their usual sleep time. This time is required for sticking the electrodes used for recording the parameters and acclimatization to the environment.
• For the Polysomnography (PSG) test to be performed in the sleep laboratory, patients bring their own pyjamas and personal belongings such as slippers and toothbrushes. During the hospitalization, you should especially come with sleeved pyjamas. You can bring some items (such as pillows, toys) that will make you feel at home. However, it is not right to watch TV and read books in order to comply with sleep hygiene in the rooms.
• If the patient is using antidepressant and sedative drugs, it is recommended to stop 1 week before coming to the sleep laboratory. You should consult your doctor about taking the medications that you need to use continuously that day. It is useful to bring the medicines you use as a precaution with you. If you are taking a sleeping pill, you should stop it 7 days before.
• You can eat dinner in the usual amount. You should avoid overeating and fatigue. If possible, do not sleep during the day on the date of the test.
• Smoking, alcohol, coffee and carbonated drinks should be avoided on the day of the sleep test. Foods such as oranges and tangerines that may cause reflux should also be avoided.
• Take a shower and wash your hair, especially in the evening, on the day of hospitalization. Make sure your hair is clean because clean hair and scalp are important for good electrodes to be connected. Do not use moisturizers, hair spray, gel and oil-containing products after showering.
• Shave beard, especially clean your chin area by shaving. However, if you have a beard longer than 1 cm, you do not need to shave, the electrodes will be connected with a special adhesive. Remove your nail polish and fashion nails, if any. It is beneficial to clean the chest hair and the hair on the front of the legs.
• The patient should come a few hours before the normal sleep time in order to get used to the environment and stick the electrodes that will record the findings. There will be no accompanying person with you during the sleep test. It is especially requested that the patients be alone and not accompanied by their relatives.
• The patient is prepared together with the technician and when he wants to sleep, he is asked to lie down and sleep. This is a completely natural process. In other words, no local anaesthetic drug etc. is applied to the patient. It is aimed that the patient falls asleep spontaneously.
• Sleep technicians continue to monitor the patient and records from another room in the same building. When the patient needs something, they help him to move and solve the problems.
• During the night, under the influence of being watched and the cables, patients wake up relatively frequently, and some patients in the morning state that they do not sleep at all. However, even under all adverse conditions, enough data is collected to provide sufficient information about the patient’s sleep efficiency.
• Although the sleep test is generally a standard practice, it is a test that should be planned and evaluated in line with the patient’s complaints. Therefore, the physician should be informed in detail about the patient’s complaints before the test.
• The results of the sleep test are evaluated and reported by an experienced physician. It can take 1-2 hours for a test to be reported. Based on the results of the report, the most appropriate treatment method can be easily determined. As a result, the sleep test is a test that is initially accepted with some hesitation, but it is a test that surprises the patient with its results and provides a lot of data to the physician.

The information on this page has been prepared by the Moodist Psychiatry and Neurology Hospital Medical Team.