Sleep Apnea and CPAP Therapy
by Rodney Petersen
Sleep apnea is a problem described as hesitations of breathing while sleeping. These hesitations are known as Apneas(meaning, "without breath"). These apnea events occur throughout the night and can be numerous enough to cause significant health problems. An overnight sleep study (polysomnogram) determines the severity and number of occurrences as well as finding the pressure (measured in cm/H20) that is needed to eliminate the apnea events. Treatable levels of sleep apnea are defined as 5 events of any type or greater per hour of sleep. During Obstructive Sleep Apnea, breathing is interrupted by a physical block to airflow despite effort.
A person with Obstructive Sleep Apnea is rarely aware of having breathing issues, even upon awakening, although many people report that they suddenly wake up gasping for air, and some hear themselves recover with a loud snore sound. Sleep apnea is usually observed by others or is suspected because of its effects on the body (sequelae). The effects may be present for many years, without self diagnosis, and the person may get accustomed to daytime sleepiness and fatigue caused by the sleep disturbances.
Obstructive sleep apnea (OSA) is the most common type of sleep-disordered breathing. The muscles of the body, especially in the throat, relax during sleep. The airway is made up of collapsible soft tissue which can obstruct the airway and limit breathing during sleep. This problem can be exacerbated by obesity and the presence of large tonsils and tongue tissue. The result is a lack of oxygen in the blood that causes a response from the brain, causing an interruption of the normal sleep cycle. The CPAP machine eliminates these interruptions of sleep by delivering a stream of compressed air through flexible tubing to a nasal pillow, nose mask or full-face mask, splinting the airway (keeping it open under air pressure) so that unobstructed breathing becomes possible, reducing and/or preventing apneas and hypopneas. This has the additional benefit of reducing or eliminating snoring.
The reduction and elimination of obstructive sleep apnea began with the invention of the CPAP (Continuous Positive Airway Pressure), first described in 1981 by Colin Sullivan in Sydney, Australia. It has evolved over time, from large noisy machines, to more compact and quiet units created in the late 1980s. Effective treatment stimulated a massive surge of clinics dedicated to the diagnosis and treatment of Sleep Apnea. Many variations of sleep disorders were recognized, and most of the patients of these centers have sleep disordered breathing. Sleep Apnea became easily diagnosed, and the CPAP machine has become the method to treat this problem.
The CPAP machine creates a pressurized flow of air through a hose to a CPAP mask worn during sleep. A CPAP mask delivers the air through a nasal interface, nasal pillow delivery system, or a full face interface that allows the patient to breathe in or out from the nose or the mouth or a combination of the two. The air pressure causes a "splinting the airway" (keeping it open under air pressure) so that free-flow breathing occurs, thus preventing apnea and hypopnea. This also creates a favorable outcome by eliminating snoring. A CPAP machine is normally used indefinitely to treat sleep apnea at the patient's home.
The CPAP machine blows air at a preset pressure (also called the titrated pressure). The necessary pressure is prescribed by a physician after reviewing the results of an overnight sleep study (polysomnography) taken in a sleep laboratory. The titrated pressure is the pressure of air, (measured in cm/H2O), that was required to open the airway and end the Apnea events. The typical pressure for most patients is between 6 and 14 cm/H2O. A CPAP machine can produce pressures of 4 to 20 cm/H2O. More advance machines, that are needed in severe cases, can go up to 25 or 30 cmH2O.
CPAP machines may also may be used to treat preterm infants whose lungs have not fully developed. For example, some doctors may use a CPAP machine to treat infants who have respiratory distress syndrome or even bronchopulmonary dysplasia.
Sleep apnea is a common disorder that causes pauses in breathing or shallow breaths while you sleep. As a result, not enough air reaches the lungs. During Apnea events the airway collapses and becomes blocked or obstructed. When inhalation is attempted, the air that pushes past the obstruction can cause loud snoring. Subsequent snoring may disturb sleep partners. The positive pressure from a CPAP machine can prevent the airway from collapsing or becoming blocked.
CPAP Therapy, is a prescribed medical treatment that uses air pressure to keep the airway open. A CPAP Machine typically is used by people who have a breathing problem, and is a very effective treatment method. CPAP systems are easily obtainable, with a prescription, from a local "Brick and Mortar" Home Medical Equipment store, or by purchasing the CPAP system and replacement supplies from on-line retailers, such as Express CPAP Supply (http://www.YouNeedSleep.com) Most online suppliers employ Respiratory Therapists to ensure proper patient care and correct set up of the equipment. Many businesses like Express CPAP Supply provide new and previously owned machines at a very low cost as an option for those on a tight budget. Medical insurance does not always cover sleep apnea equipment, so web based businesses have become a significant part of overall CPAP equipment sales, ever increasing since the mid '90's. Ordering from the comfort of home is very well received, as patients can save time and money and have their supplies delivered right to their door.
OSA(Obstructive Sleep Apnea) treatment involves a CPAP System, which has three main parts:
1. A CPAP mask or other device that fits over your nose or your nose and mouth, some cpap masks just touch the CPAP user's nostrils. Headgear straps keep the mask in place.
2. A Flexible hose (Tubing) that connects the mask to the machine's motor.
3. A CPAP machine (Flow Generator) that blows air(Positive Airway Pressure) into the tubing, delivering it to the CPAP mask.
Some CPAP machines have other features as well, such as heated humidifiers for added comfort, exhalation pressure relief (EPR™ also named C-Flex™, A-Flex™, Bi-Flex™, Smart Flex™), CPAP machines are small, lightweight, and quiet (23-30dB). The noise from a CPAP machine is usually soft and rhythmic.
Process for starting CPAP Therapy
If a physician prescribes a CPAP system, the patient will be directed to a home equipment provider. (Home equipment providers are also referred to as durable medical equipment, or DME.) The physician will work with the patient to make sure the settings that he or she prescribed are correct. He or she usually requires the patient to complete an overnight sleep study to find the correct settings for the system pressure. The sleep study will measure how much pressure is needed to keep the airway open during sleep.
CPAP machines have variations in size, options, colors, and operation, and come from a variety of different manufacturers. CPAP masks also have a variety of sizes, colors, materials, and features, some only covering the nose, while others cover the whole face. Some are made with a silicone like cushion to create a seal between the face and the mask, while others use a Gel filled cushion. Some now are even made from a cloth material that is not porous enough for the air to penetrate. If a patient cannot tolerate the mask given, the physician may suggest switching to a different style. Many sources for replacement CPAP systems, machines, masks and accessories are available. Some examples of these are from the person's medical clinic, by visiting a local "Brick and Mortar" home medical supply store, or by ordering from the comfort of your home by purchasing the equipment on the Internet from on-line retailers, such as Express CPAP Supply (http://www.YouNeedSleep.com).
CPAP machines are also is used to treat preterm infants whose lungs have not fully developed. For this treatment, soft prongs are placed in an infant’s nostrils.
A CPAP has many benefits. It can;
Keep the airway open during sleep
Eliminate loud snoring so others in the household can sleep Improve the quality of sleep, even at a reduced sleep time
Relieve sleep apnea symptoms, such as excessive daytime sleepiness, headaches, and moodiness
Decrease or prevent high blood pressure Many people who use a CPAP machine report feeling better as soon as they begin treatment. They feel more attentive and better able to work during the day. They also report fewer complaints from bed partners about snoring and sleep disruption.
The medical benefits are numerous. Sleep apnea has been determined to cause or increase impotence and a lowered sex drive, Obesity, Alcohol and Drug Dependencies, Lack of Exercise, Vision Problems, Diabetes and many others
A widely used solution and arguably the most consistently effective treatment for sleep apnea is the use of a continuous positive airway pressure (CPAP) device , which 'splints' the airway open during sleep by means of a flow of pressurized air into the throat. However the CPAP machine only assists during inhalation. The lungs must prompt exhalation. The exhalation is more difficult at higher CPAP pressure settings. A Bi-Level CPAP, often called BIPAP or VPAP can provide ease of exhalation by reducing the positive pressure when the start of exhalation begins, then the flow generator returns to the higher inhalation pressure. CPAP therapy is effective only for (OSA)Obstructive Sleep Apnea, not for central or mixed cases.
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