A continuous positive airway pressure (CPAP) system is a medical device which is designed to keep a patient's airway open while providing respiratory ventilation so that the patient can breathe. These systems were originally used in the treatment of obstructive sleep apnea (OSA), but they are also used in some medical settings such as intensive care units. In contrast with respiratory ventilators which require intubation, a CPAP system is very easy to use, and it usually has less side effects.
With a CPAP system, a patient wears either a face mask or a nasal pillow, and a CPAP generator connects with a tube. The generator creates a steady flow of pressurized air which holds the patient's airway open, sort of like how the pressured air inside a balloon keeps the balloon inflated. If a patient cannot breathe on his or her own, the CPAP system provides a steady supply of air, while patients who suffer airway closures when they sleep will not have experience airway obstructions while using a CPAP system.
For people with apnea, a CPAP device can make it easier to sleep through the night. Patients with OSA wake up repeatedly as a result of the airway closures they experience in their sleep, and they can develop daytime fatigue and a number of other problems if the apnea is not treated. With CPAP, patients can sleep safely, and symptoms such as snoring and insomnia will be resolved. It can take some time to get used to sleeping with the machine.
CPAP systems are not usually available over the counter, because the air pressure needs to be prescribed by a doctor. For apnea patients, the prescription is usually written by a sleep doctor who determines the level of pressure necessary to keep the airway open, while patients in the hospital will have their CPAP systems adjusted by doctors and nurses if needed. Getting the right pressure is critical, as pressure which is too high can damage the lungs.
There are a number of variations on the CPAP system. An auto-CPAP will modulate the pressure in response to the patient's respirations, and bi-level CPAP machines reduce the pressure when patients breathe out. Since patients sometimes complain of discomfort while wearing a CPAP machine, these more advanced devices can increase compliance with a CPAP prescription by making it easier for the patient to wear the device. Some CPAP machines can also humidify the air and perform other functions, including logging data about a patient's respiratory rate.
