by Mile High Sleeper
An overnight sleep study in a sleep lab is the gold standard of diagnosis. It’s a very sophisticated way of testing for sleep apnea – obstructive (the most common kind), central (more rare), or mixed or complex – by checking airflow in your throat, snoring, and the effort your chest makes to breathe in various positions and in different stages of sleep. A lab study will also check for Restless Leg Syndrome, the amount of oxygen in your blood, and your heart rate and rhythm. If your doctor orders a sleep study, insurance or Medicare should pay for it. A split night sleep study may cost between $1,500 and $4,000.
Option 1 In the most common, one-night “split study,” half the night is spent measuring your sleep, creating a polysomnogram (PSG) which is later interpreted by a physician. If you seem to have Obstructive Sleep Apnea (OSA), the second half of the night is spent using a CPAP (Continuous Positive Airway Pressure) machine to find the best airflow pressure setting for you.
Advantages of a split study: lower cost, since it’s only one night. If the sleep technician gives you a mask, you get fast feedback in the middle of the night that you most likely have OSA. Later, upon receiving the report, you have a pressure setting for a doctor’s prescription for a CPAP machine.
Disadvantages: if you have concerns about falling asleep in a lab setting, or worry about wearing a respiratory mask for the first time, you may not fall asleep or have poor quality sleep, resulting in an inconclusive outcome or poor study. The sleep technician has less time to record your sleep cycles to do the sleep study and less time to find an effective titration setting, a slow trial-and-error process which requires your sleep.
Option 2 A second option is a two-night study. It’s the same process as a split study, but a full night is used for each part. The first night is a baseline study of your sleep. The second night is a titration study to establish a CPAP pressure setting.
Advantages of a two-night study: Alleviates mask fear on the first night since no mask is needed, supporting better sleep and a better study. The technician has plenty of time to record sleep cycles and on the second night, plenty of time to try various pressure settings during the titration.
Disadvantages: twice the cost of a split study. It will take additional time to schedule the second study and get a pressure setting, which could delay the start of treatment.
Option 3 A third option is a single baseline study and use of an APAP machine instead of a titration study to determine pressure settings. After a baseline study report of OSA (the first night), if CPAP seems to be the best treatment, and if you are a candidate for APAP (an Auto-titrating Positive Airway Pressure) machine, you can get a prescription and machine long before a second night study. In fact, with an APAP machine and software and helpful doctor, it may not be necessary to have a second titration study. The APAP machine can be used to determine pressure settings instead of sleep lab titration. Research:
American Journal of Respiratory and Critical Care Medicine, Can Patients with Obstructive Sleep Apnea Titrate Their Own Continuous Positive Airway Pressure? http://ajrccm.atsjournals.org/cgi/content/full/167/5/716 Quote: Home self-titration of CPAP is as effective as in-laboratory manual titration in the management of patients with OSA.
Nonattended home automated continuous positive airway pressure titration: Comparison with polysomnography http://www.sleepsolutions.com/clinical_library/Unattended_auto-CPAP.pdf Quote: Nasal APAP titration in this study correctly identified residual apnea equivalent to the use of PSG. This correct identification allows the physician to accurately access the efficacy of treatment.
Advantages of a baseline study and APAP: lower cost, since it’s only one night. Alleviates mask fear during the study since no mask is needed, supporting better sleep and a better study. The technician has plenty of time to record your sleep cycles. If you do require a second night titration study, it can still be done later. Requirements: 1) the physician’s decision about the efficacy of auto-titration settings instead of sleep lab titration. 2) prescription of an APAP machine able to record daily details, machine setup manual, and software. 3) physician and patient experimentation to find optimal pressure settings. 4) frequent software downloads by the patient (or a cooperative Durable Medical Equipment /home care provider, DME). None of this is extraordinary; it’s equipment and a feedback process that may be selected by the doctor and patient regardless of type of sleep study.
The deciding factors among the sleep study options may be a combination of your medical and psychological needs, your physician’s advice and support, and your insurance or Medicare coverage or your ability to pay out-of-pocket for APAP machine software. Discuss your needs with your physician and find out what your insurance company or Medicare supports and requires. Insurance companies tend to pay for a sleep study and CPAP equipment, because it’s more cost effective than paying for treatment of heart failure or stroke, treatment of car wreck injuries, and other serious health conditions resulting from untreated sleep apnea. Medicare usually requires a sleep study before paying for CPAP equipment. Does your insurance company have the same requirement? What impact do your deductible and co-pay have on your costs for various options? If possible, it may be more expedient to avoid scheduling your sleep study during the last quarter of the year, since the sleep lab may be overly busy then because people wait to schedule testing until they have reached their calendar year insurance deductible. However, if sleep apnea is suspected, it’s best to be tested and get your equipment as soon as possible.
For a brief description of the Maintenance of Wakefulness Test and Nap Study, see http://www.sleepeducation.com/Studies.aspx
In-home test though a physician. Some physicians and insurance companies suggest an in-home test. The patient wears various sensors and belts through the night. The results are monitored and reported. Sleep stages and brain waves cannot be measured as they are in a laboratory sleep study. One in-home process used by Kaiser, http://www.sleepdata.com/homecare.htm, measures apneas and hypopneas per hour, heart rate, respiratory effort, nasal-oral airflow, oxygen saturation using a pulse oximeter, body position, and snoring intensity and frequency. Simpler devices are the SLP Sleep Strip, http://www.slp-med.com/SleepStripTech.htm and the Accutest SleepStrip, http://www.accutest.net/products/sleepstrip.php. If you explore these alternatives, discuss with your physician the need and ways to detect OSA (obstructive sleep apnea) vs. central apnea (brain not giving a signal to breathe) and mixed sleep apnea (combination of OSA and central), since treatment is different for the three types, as well as detecting other sleep disorders such as Restless Leg Syndrome. Also determine whether your insurance or Medicare will pay for subsequent treatment based on testing that is not the standard sleep study.
Inexpensive screening for obstructive sleep apnea for the uninsured, for those who can’t afford insurance co-pays for a sleep study, or for those who want screening before a sleep study: http://www.cpap.com/productpage/slp-sleep-strip-at-home-sleep-study.html
Diagnosis based on symptoms and perceived need may be an option for non-insured patients or patients with highly suspected obstructive sleep apnea (OSA) based on symptoms. Not Every Patient Needs to Go to the Sleep Lab, http://www.alaccoast.org/pdf/Phillips_0830.pdf is a thought-provoking Powerpoint presentation by a well respected board certified sleep doctor/pulmonologist, Dr. Barbara Phillips, at a meeting of the American Lung Association of the Central Coast in November 2004. Dr. Phillips is a professor of medicine at the University of Kentucky and is on the board of directors of the National Sleep Foundation. This approach would not detect central sleep apnea or mixed sleep apnea. Treatment differs depending on the diagnosis. If eligible, find out whether Medicare or Medicaid would pay for subsequent treatment without an overnight laboratory sleep study.
Apnea. The Greek word “apnea” means “without breath.” You stop breathing during sleep for ten seconds or longer.
Hypopnea. There is airflow through your throat but at a much reduced level, which leads to not getting enough oxygen. It’s abnormally shallow breathing lasting at least ten seconds.
AHI, Apnea-Hypopnea Index for Obstructive Sleep Apnea: Less than 5 events (apnea or hypopnea) per hour is considered normal. 5 or more events per hour is considered Mild 15+ considered Moderate 30+ considered Severe (from T. S. Johnson MD, Sleep Apnea - The Phantom of the Night, page 211)
A sleep study uses a pulse oximeter, a device with a red light that clips on your finger. It measure oxygen levels in your blood by noting the color; oxygenated blood is bright red, blood with hemoglobin desaturation is darker red.
There are two chapters on sleep testing and understanding your report in the book Sleep Apnea – The Phantom of the Night by TS Johnson MD et al.
“Introduction to the Sleep Lab” Order from http://www.cpap.com/productpage/cpaptalk.com-introduction-to-the-sleep-lab.html Allow time for delivery or view online at http://www.cpaptalk.com/cpaptalk-cpap-video-movie.php?videos=video&VGID=58
• Expect elaborate headgear, face straps, and stiff, bulky plastic nose pieces that make you look like an astronaut.
• While the sleep technician puts the mask on you, breathe through your mouth.
• Before you are hooked up to the CPAP machine, ask the technician to let you feel the airflow from the hose on your hand. It’s surprisingly breezy. It will feel much less breezy when felt through a mask.
• You won’t need it, but to make you more comfortable psychologically, ask the technician to show you how to quickly remove the mask and how to disconnect the mask from the hose or CPAP machine. The technician will show you how to call him or her during the night.
• While sitting up, spend a few moments “practice breathing” through the mask with CPAP turned on. It works! You can do it. You can even fall asleep while wearing it.
Comments from a SleepStrip engineer: http://www.cpaptalk.com/viewtopic.php?t=14035&postdays=0&postorder=asc&start=15=Sleep Symptoms=