What is Sleep Apnea?
Usually when you sleep, the muscles that control the upper airway relax, this is normal. However, if they relax too much the airway narrows and you snore. The muscles can relax even further causing a blockage of the airway and you actually stop breathing. This is called “Obstructive Sleep Apnea” (OSA). Other factors can cause this as well. An enlarged uvula or swollen tonsils, a nasal obstruction or certain facial attributes can also cause OSA. Each episode can last ten seconds or more and has been known to happen hundreds of times a night disrupting your sleep without you even being aware that it’s happening.
If you suspect that you might suffer from sleep apnea and you don’t seek treatment you put yourself at risk for:
- High Blood Pressure
- Fatigue Related Accidents
- Heart Attack
- Strained Relationships
- Heart Disease
- Decreased Quality of Life
What are the different types of sleep diagnostic options I have?
Polysomnogram – Polysomnography is a sleep study. A sleep study monitors you as you sleep, or try to sleep.
There are two states of sleep:
- Rapid eye movement (REM) sleep is when you dream. Your muscles (except your eyes and breathing muscles) do not move during this stage of sleep.
- Non-rapid eye movement (NREM) sleep has four stages that can be detected by brain electrical activity (EEG) waves.
REM sleep alternates with NREM sleep about every 90 minutes. A person with normal sleep usually has four to five cycles of REM and NREM sleep during a night.
A sleep study measures your sleep cycles and stages by recording:
- Air flow in and out of the lungs during breathing
- Blood oxygen levels
- Body position
- Brain waves (EEG)
- Breathing effort and rate
- Electrical activity of muscles
- Eye movement
- Heart rate
CPAP Titration Study – This study is used to set the right level of continuous positive airway pressure (CPAP) for a person who will receive CPAP therapy as a result of their sleep disorder, such as Obstructive sleep apnea (OSA), Central sleep apnea (CSA) or Hypoventilation and hypoxemia.
How is the study performed?
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.
Home Sleep Test (HST) – HSTs offer the advantage of allowing testing in the patient’s own home and with less instrumentation, thereby theoretically providing a more natural sleeping environment.
The minimal number of sensors used during an HST limits home sleep testing to only be able to diagnose sleep apnea, while in-lab tests are able to identify and diagnose most sleeping disorders. Additionally the lack of a trained sleep technologist during home testing who, among other responsibilities, is able to recognize when a sensor has come off during the night and replace it while the patients sleeps, allows a greater potential for inaccurate tests and misdiagnosis.
Multiple Sleep Latency Test (MSLT) – The MSLT is a sleep disorder diagnostic tool. It is used to measure the time elapsed from the start of a daytime nap period to the first signs of sleep, called sleep latency. The test is based on the idea that the sleepier people are, the faster they will fall asleep.
The MSLT is used extensively to test for narcolepsy, to distinguish between physical tiredness and true excessive daytime sleepiness, or to assess whether treatments for breathing disorders are working. Its main purpose is to discover how readily a person will fall asleep in a conducive setting, how consistent or variable this is, and the way they fall asleep in terms of REM sleep and other brain patterns. This can be used to identify and differentiate between various sleep problems.
The test consists of four or five 20-minute nap opportunities set two hours apart, often following an overnight sleep study. During the test, data such as the patient’s brain waves, EEG, muscle activity, and eye movements are monitored and recorded. The entire test normally takes about 7 hours during the course of a day.
Maintenance of Wakefulness Testing (MWT)
The Maintenance of Wakefulness Test (MWT) is used to measure how alert you are during the day. It shows whether or not you are able to stay awake for a defined period of time. This is an indicator of how well you are able to function and remain alert in quiet times of inactivity.
The test is based on the idea that your ability to stay awake may be more important to know in some cases than how fast you fall asleep. This is the case when the MWT is used to see how well a sleep disorders patient is able to stay awake after starting treatment. It is also used to help judge whether a patient is too tired to drive or perform other daily tasks.
The sleep specialist will help you decide what you can and cannot have. You may be asked to take a test to screen for drugs on the morning of the MWT. It will help show that the results of the MWT are accurate.
The MWT is used to see if someone with a sleep disorder is responding well to treatment. Results of multiple tests may be compared over a period of time. This can show if treatment is helping a patient overcome sleepiness. The MWT may be used to evaluate how well a person with a sleep disorder is able to stay awake. This is critical when the person’s job involves public transportation or safety. The results of the test will be only one factor used to assess the potential risk of a work-related accident.
PAP ADAPT – The newly developed United Sleep Diagnostics PAP ADAPT! Program is designed to assess and alleviate physical and emotional barriers to effective use of CPAP. PAP ADAPT! is a daytime program lasting from 2-5 hours which includes, a nap of 1 to 2 hours, hands on coaching (delivered by specially trained sleep technicians under the supervision of a physician) and same day feedback for your patient regarding the issues preventing CPAP compliance. We will follow up with you to let you know the results of the patient’s progress in the PAP ADAPT! program.
The following are candidates for the PAP NAP procedure:
- Patients who have failed to complete a Split/Titration study due to emotional or psychological barriers.
- Patients who are not complaint to PAP therapy.
- Patients who report insomnia related to psychological barriers to PAP use.
Success will be measured by patient’s ability to tolerate PAP use and positive subjective feedback. All feedback will be documented including patient’s opinions, feelings, technician’s impression and patient’s ability to tolerate mask/pressure.
What Can You Do?
Once a diagnosis has been made, your options will be explained to you. Together, we determine the most effective treatment for your particular sleep disorder.
Click here to learn more about Sleep Apnea and what you can do about it.
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