What is it?

This study is used to set the right level of continuous positive airway pressure (CPAP) therapy. This therapy is used for people with sleep related breathing disorders. These disorders include the following:

• Obstructive sleep apnea (OSA)
• Central sleep apnea (CSA)
• Hypoventilation and hypoxemia

CPAP is most commonly used to treat OSA.

Who gets it?

A CPAP study is performed on someone with a sleep related breathing disorder. This is usually a person who has OSA.

What happens when I have it?

During an overnight sleep study, you may show signs of having OSA. If it seems to be very severe, then a CPAP study may be performed right away. Doing both studies in one night is known as a split-night sleep study.

If the sleep study shows that the OSA is fairly mild, then the CPAP study may not be performed right away. The doctor may wait to review the results of the entire night of the sleep study. Then he or she will decide if you need to come in for a second sleep study. If you do, then the CPAP study would be performed at that time.

During the CPAP study, you are fitted with a nasal mask. The mask is connected by a tube to a small electric unit. The unit has a fan that pushes air through the tube. The mask allows the air to gently blow into the back of your throat.

Pressure is started at a very low level. It is then increased at various intervals during the night. The goal is to find the right level of air pressure that will prevent the collapse of your upper airway. This eliminates pauses in your breathing as you sleep.

Who reads it?

A technologist is the first one to look over the data from a sleep study and a CPAP study. First, he or she will chart your sleep stages. Then, he or she will look for any events of abnormal breathing or leg movement. He or she will also record how events of abnormal breathing decreased once the CPAP mask was used.

The results will be given to a doctor. The doctor will review the study to find out what level of CPAP treatment will work best for you on an ongoing basis.

Many sleep centers are accredited by the American Academy of Sleep Medicine (AASM). The AASM sets strict standards for centers to maintain. This is to make sure that patients with sleep disorders get the highest level of care. In these centers, the results of a CPAP study are always reviewed by a specialist who is certified by the American Board of Sleep Medicine.

How do I get the results?

It usually takes about two weeks to get the results of a CPAP study. At times the doctor who takes a look at the study needs to get more information. He or she may talk to the technologist or to the doctor who sent you to the center.

The doctor who ordered the study will discuss the results with you. If your primary care doctor ordered it, then the results are sent to him or her. If you met with a doctor in the sleep center, then he or she will tell you the results. You are then able to be fitted for a mask and to obtain a CPAP unit for use in your home.