There are two main machines commonly used to treat the symptoms of sleep apnea, a condition in which an obstructed airway affects a person's breathing during sleep. The most common of these is the continuous positive airway pressure (CPAP) device, while the bi-level positive pressure (BiPAP) device may be used in more severe cases. The CPAP is a ventilator that provides positive air pressure to keep a person's airway unobstructed through the night, while the BiPAP ventilator can assist in both inhalation and exhalation.
There are a few variations of these main sleep apnea machines. There also is a technique known as oral appliance therapy (OAT). OAT can sometimes achieve a similar effect to sleep apnea machines by forcing a person's lower jaw forward to keep his or her airway from closing.
CPAP sleep apnea machines function by providing pressurized air to a person's airway while they sleep. This can have the effect of preventing apnea by forcing the airway open, but it will only assist with inhalation. Typical CPAP machines need to be calibrated by a doctor prior to use to provide the correct amount of pressure. The air pressure is what prevents a person's airway from closing, so this calibration can differ from person to person.
The other main type of sleep apnea machine is the BiPAP device, which is designed to assist in both inhalation and exhalation. This type of sleep apnea machine is able to vary the positive pressure that it applies. A higher pressure can be applied during inhalation, while a lower pressure can be applied during exhalation. This can make a BiPAP device useful in treating some of the more severe cases of sleep apnea. BiPAP devices may sometimes also be referred to as BPAP or variable positive air pressure (VPAP) devices.
There are also a few variations and additional features available for these main sleep apnea machines. Automatic positive airway pressure (APAP) devices are a form of CPAP that can recalibrate automatically throughout the night. This allows the APAP to always provide the precise pressure required to keep the airway open. There are also various options available for CPAP and BiPAP machines, such as one that will humidify and warm the air. CPAP machines also have an option available that can provide a temporary drop in pressure during exhalation that can achieve an effect similar to that of a BiPAP machine.
In certain cases of sleep apnea, a doctor may determine that a non-mechanical dental appliance is the best treatment. While not technically a sleep apnea machine, these OATs can achieve similar results. The treatment involves fitting and placing an appliance in the mouth to force the lower jaw forward during sleep. This forward movement of the jaw can force the airway open and prevent apnea in a manner similar to sleep apnea machines. This method is generally used in less severe cases of sleep apnea if a doctor determines it might be effective.