Sleep Apnea and The Home Sleep Test Option
By Kevin Hofstetter // May 11, 2012
Let’s think outside the box. What if technology allowed patients to be tested with portable diagnostic equipment in their home? What if we could make testing for sleep apnea easy, more available to patients, reliable, and cost effective? That’s what a home sleep test can do.
A home sleep test is a diagnostic test to determine the presence of sleep apnea, which is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing during sleep.
Risk factors for sleep apnea include loud snoring, being overweight, and high blood pressure. It is quite common and increasing in prevalence, with as many as 18 million American men and women of various ages and weights currently suffering from the disorder.
Symptoms of sleep apnea may include, loud snoring, pauses in breathing, gasping for breath during sleep, daytime sleepiness, morning headaches, depression, and irritability. It has also been linked to high blood pressure irregular heart rhythms, heart disease, heart attack, stroke, diabetes, driving and workplace related accidents.
The availability and use of small monitoring devices has made it easy and convenient to be tested in the comforts of home rather than overnight in a sleep lab. The equipment that is used consists of a small data collection device, sensors to measure airflow and blood oxygen content, and belts to measure breathing movement.
The data-recording device receives and stores information from the sensors during sleep in the comfort of a patient’s own bed. The amount of data collected depends on the number of sensors used in the test.
Registered sleep technologists instruct patients on the operation of the testing equipment and are always available by telephone for any questions. When the study is completed, the equipment is returned and the data is securely downloaded. All information is reviewed and interpreted by a physician expert in sleep medicine.
In comparison, an overnight sleep study done in a sleep lab is not limited to the analysis of just sleep apnea, but can also detect a wide range of other sleep disorders. A home sleep test only detects obstructive sleep apnea, so it collects less information.
Measures Airflow, Breathing Effort and Blood Oxygen Levels
Most home sleep tests measure airflow, breathing effort and blood oxygen levels.
Varying reductions in airflow or pauses in airflow signify a breathing disorder such as hypopneas and apneas. Hypopneas are episodes of reduced or shallow breathing. Pauses in breathing, where there is no airflow are called apneas. A home sleep test determines how many hypopneas and apneas may occur in a night. Only respiratory events 10 seconds or longer are recorded.
Breathing effort is tracked and documented because there is often pauses in breathing that occur with sleep apnea even though breathing effort is present. The most effective way to measure breathing involves wearing an expandable belt around the chest and abdomen. The belts use sensors and wires to measure the breathing effort.
Blood oxygen level is also recorded in a home sleep test. When an apnea or hypopnea occurs the oxygen level in the blood stream may fall below normal values or limits. The blood oxygen level is measured via a small sensor worn on the finger.
Home tests aren’t for everyone. If you have a sleep disorder, discuss your symptoms and risk factors with your physician to determine if a home sleep test might be a good option for you. Even if you don’t want to go to a sleep lab, it’s still important to have a full exam with a certified sleep specialist to determine whether you can skip the overnight lab study.
ABOUT THE AUTHOR
Kevin Hofstetter is the Director of Business Development and Clinical Services for AmEx Disease Management. He has received credentials from the American Academy of Sleep Medicine as a Registered Polysomnographic Technologist, the American Board of Sleep Medicine as a Registered Sleep Technologist, the National Board for Respiratory Care as a Certified Respiratory Therapist, and the National Board for Respiratory Care as a Certified Pulmonary Function Technologist. He can be reached at firstname.lastname@example.org or at amexdm.com