The Continuous Positive Airway Pressure (CPAP) machines are used to treat obstructive sleep apnea (OSA), a sleep-related breathing disorder. Sleep apnea occurs when the upper airway becomes blocked repeatedly during sleep, resulting in the airflow partially or completely stopping.

People who have sleep apnea have problems with keeping the airway open for normal breathing as they sleep. Most commonly, the soft tissue in the throat and oral cavity (the tonsils or tongue, for instance) relaxes and/or collapses, closing off the space needed for air to move through the nose and into the lungs. This leads to pauses in breathing that can happen consistently enough, and long enough, to deprive the bloodstream of the oxygen it needs to deliver to all the organs.

The brain senses this drop in blood oxygen and forces an awakening. However, some people can experience more than 100 of these pauses and awakenings per hour for most of the night! It's no wonder why some people with severe sleep apnea feel so tired all the time.

It was created to help keep these pauses from happening. The machine, by way of the tubing and mask, delivers a stream of pressurized air as a kind of "pneumatic splint" to help prevent the collapses that are characteristic of obstructive sleep apnea. By helping to keep the airway firm and open, the pressurized air provides the support necessary for the user to breathe freely and without obstructions.

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