Sleep apnea is a critical sleep disorder in which the person stops breathing for 10 to 30 seconds while sleeping. It can occur 5 to 30 times an hour. Apneas are usually calibrated during sleep over a two-hour period. An estimate of the severity of apnea is calculated by dividing the number of apneas by the number of hours of sleep, giving an apnea index (AI in apneas per hour). The greater the AI, the more severe the apnea. Sleep apnea is a chronic condition that disrupts sleep and causes tiredness or sleepiness during the day. In severe cases, treatment is required to prevent low blood oxygen (hypoxemia), sleep deprivation and other complications. The most serious complication is a congestive heart failure.
Continuous Positive Airway Pressure (CPAP) therapy is the process used to cure sleep apnea. The therapy was initially developed in 1981 by Professor Colin Sullivan at the Royal Prince Alfred Hospital in Sydney, Australia. The modern CPAP devices are regarded as the best non surgical treatment to get relief from snoring and sleep apnea. The CPAP machines deliver air into the airway through a scientifically designed nasal CPAP mask or full face CPAP mask. The air flow maintains suitable pressure while a person breathes in, to keep the airway open. A CPAP machine is set to a specific pressure level with slight variation from the continuous pressure. These breathing devices help in restoring regular breathing during the sleep and also relieve snoring and daytime sleepiness.
The CPAP masks may cover the mouth, and parts of the face and forehead. They are held securely in place by head straps. The masks are devised in a user friendly manner to provide full comfort while sleeping. These machines can generate variable pressure, ranging from 4 to 20 cubic centimeters. Air flow rates may be varied depending on the patient’s airway resistance. Appropriate airflow rate is the one that allows the oxygen levels in blood to be kept at normal levels.
CPAP machine are of two types: Nasal CPAP and Bi level positive airway pressure (BiPAP) machines. The nasal CPAP machines deliver continuous airway pressure while breathing in and breathing out. Alternatively, Bi PAP machines have a mechanism to adjust the pressure only while breathing out. Bi PAP machines are generally used to treat sleep apnea in kids. Main features of CPAP machines are: