If you suspect that you suffer from sleep apnea, your doctor may prescribe a continuous positive airway pressure machine, also known as CPAP, to keep the problem in check. A CPAP sends air, or positive pressure, into your airways to keep the passages open when you sleep. Sleep doctors determine each person's customized settings by performing a CPAP test. During this test, patients report to a sleep lab, where they are given a room with a bed and fitted with a CPAP mask. While the patient sleeps, settings are adjusted to optimize nighttime breathing.
Ordering the Test
A CPAP test will be ordered by a physician for several different reasons. One reason may be to determine the best initial CPAP settings to treat obstructive sleep apnea. A doctor may also recommend a CPAP test to verify if current settings are optimal after a major change in medical condition or significant change in weight. The CPAP test allows a physician to verify which CPAP settings eliminate obstructive sleep apnea in the patient.
Preparing for a CPAP Test
Having a CPAP test entails spending the night in a sleep laboratory. Therefore, pajamas, nightly medications and any other needed items should be brought to the lab. If a patient is already using a CPAP, he should bring his current CPAP mask to the test. Otherwise, a CPAP mask will be provided by the sleep lab. Individuals should avoid napping and avoid excessive caffeine the day of the test to facilitate sleep at night.
During a CPAP Test
Sleep lab employees will give each individual an evening check-in time and a morning check-out time for the CPAP test. Times vary from facility to facility, so individuals should check with their sleep lab for specific times. Some labs provide showers and private bathrooms, while others are set up with shared accommodations.
When arriving for a CPAP test, individuals are assigned to a bedroom and a sleep technician. The sleep technician will collect medical information about the individual being tested and verify the reason for the CPAP test. Next, the sleep technician will attach a number of electrodes to the patient's body for monitoring. This includes wires for monitoring brain waves, eye movements, chest movements, abdominal movements, leg movements, heart rate and oxygen levels. The sleep technician will also fit the individual being studied with a CPAP mask. The mask should make a good air seal and be reasonably comfortable.
After completion of the set up, the individual having the test will be asked to go to sleep. While sleeping, the technician will change the settings of the CPAP machine to normalize breathing.
Risks
There is minimal risk associated with having a CPAP test. One should consider risks associated with spending the night away from home and the potential for minor skin irritation from electrodes placed on the body with adhesive. Risks associated with CPAP use should also be considered as part of having a CPAP test. According to Webmd.com, risks of using CPAP include: nightmares and excessive dreaming during early use, dry nose and sore throat, nasal congestion, runny nose, sneezing, irritation of the eyes and the skin on the face, abdominal bloating, leaks around the mask because it does not fit properly, and nosebleeds.
After a CPAP Test
After waking up in the morning, the patient's electrodes are removed and the CPAP test is concluded. The results of the test are usually not immediately available, as most sleep laboratories require time for physicians to review the data. Once the sleep physician has reviewed the data, he will write a prescription for the best CPAP settings. In most cases, patients should make an appointment with their physician to discuss the results of the test.
