Testing for Sleep Apnea: How it Works and What to Expect

By Admin

What Happens During a Sleep Study?

Clinical sleep medicine has received much attention in recent years as public awareness of sleep disorders like obstructive sleep apnea (OSA) has increased significantly. More and more people are thinking about sleep health, and as a result, testing for sleep disorders has become as routine as an annual physical exam. As sleep clinics take in more patients, home tests are becoming more sophisticated in their collection of data, giving patients more than a single option when confronting potential symptoms. If you are having trouble sleeping or experiencing sleep apnea symptoms such as heavy snoring or loss of breath, the first thing you should do is talk to your doctor. If there is reason to believe that a patient may have sleep apnea or other sleep disorders, a doctor will often refer them to a sleep clinic for an overnight study. There, sleep technicians use a polysomnogram to monitor and record brain activity, eye and body movements, vital signs, and oxygen levels throughout the night. Electrodes are placed on the face, scalp, and body to register electrical signals generated by brain and muscle activity during sleep, and the patient is approached in the morning with a summary of the findings. On the night of the study, patients are assigned private bedrooms in which to rest. And the technicians will be awake throughout the night in a monitoring area just outside the room. If there are any problems falling to sleep or other difficulties, the technicians can be summoned via call button for assistance. In most cases, patients are able to fall asleep easier than they might think. The room is designed for comfort, lights are turned out, and soft music is provided if the patient desires it. If the results of an overnight test show enough abnormalities, a doctor may be able to diagnose and treat a disorder without further testing. But in some cases, further tests are needed for an accurate diagnosis, including a referral to an ear, nose and throat doctor if there are signs of blockage along the airway. Some issues related to sleep apnea may require a visit to a cardiologist, neurologist, or other specialist to look at potential causes of the apnea events themselves.

Multiple-Night Evaluations and CPAP Titration

If there is reason to believe that a patient has an advanced case of either obstructive or central sleep apnea, two or more nights of evaluation and CPAP titration may be advised. In these cases, patients will return after the first night of diagnostic evaluation to determine the right air pressure for CPAP (continuous positive airway pressure) treatment. This is referred to as a CPAP titration study, a type of in-lab sleep study used to calibrate the most effective settings for continuous positive airway pressure (CPAP) therapy. The goal of a titration study is to find the right amount of air pressure to prevent the upper airway from becoming blocked, thereby reducing or eliminating those moments of halted breathing during the night. The technician remotely changes the air pressure received through the CPAP mask, starting at a low level and gradually increasing as needed. Although the development of auto-titrating CPAP devices has in part removed some of the need for laboratory CPAP titration assessments, some doctors and patients prefer a reading from a specialist when serious health problems are at stake.

Sleep Testing from Home

If your symptoms are infrequent or do not necessitate a visit to a specialist right away, a doctor may suggest a Home Sleep Test (HST). A number of simplified home test devices can be used to diagnose sleep apnea or other disorders in the privacy of a patient’s own bedroom. These tests measure the same vital signs of heart rate, blood pressure or blood oxygen level, airflow, and breathing patterns, but using a more streamlined device created specifically for the purpose of recording and assessing sleep data. But keep in mind that these devices do not always detect every case of sleep apnea, so sleep studies may be recommended even when initial home test results are found to be normal. One of the benefits of the home test is that you can test more than once. With multiple records, it is much easier to recognize patterns or anomalies that may arise.

Testing With Apps and Smart Devices

Another option that is becoming extremely popular with the proliferation of smart device technologies is the use of sleep monitoring applications. Programs like Neybox Digital’s Pillow Automatic Sleep Tracker, the S+ by Resmed, or the new Apnea App from Sleepscore Labs are extremely convenient and portable recording systems developed for use in just about any settings. Transforming mobile devices like smartphones and smartwatches into portable sleep labs, these apps use sonar reflection recordings paired with diagnostic algorithms that identify various sleep apnea events such as obstructive apnea, central apnea, and other related hypopnea.

Which Option is for Me?

As mentioned in the beginning of this article, your first step should always be a visit to your regular doctor to discuss whatever symptoms or concerns you may be having. Some studies have shown that home sleep testing and autotitrating CPAP can be as effective as a laboratory testing environments. However, these studies have focused on patients who “had a high pretest probability of OSA, were diagnosed with moderate to severe disease, and were treated with CPAP only” (Donovan, et al.). This means that home tests pick up on the more obvious cases of apnea or other sleep disorders, but may not have the precision and effectiveness of a laboratory setting involving trained professionals in the field. Thus, professional guidelines recommend use of home testing devices and apps for patients with a strong likelihood of having the targeted disorder. So at risk of repetition, the discussion begins and ends at the office of the general practitioner. Whichever diagnostic course you wish to take as a patient with sleep health concerns, a health professional’s guidance will allow you the confidence of knowing not only that you have made an appropriate decision, but that you have ongoing support as well. Having taken the first step of seeking professional help, you should be able to rest easier knowing that a correct diagnosis and treatment will reduce your symptoms in time. And resting easier is exactly what you should be doing.