Definition
CPAP stands for "continuous positive airway pressure." CPAP is a treatment that delivers slightly pressurized air during the breathing cycle.
This keeps the windpipe open during sleep and prevents the episodes of blocked breathing in persons with obstructive sleep apnea and other respiratory problems.
 
It is sometimes called nasal continuous positive airflow pressure (nCPAP).
 
References
Mechanical ventilators(critical care ventilator, home care ventilator, ICU ventilator, intensive care ventilator, emergency ventilator) are used for testing in obstructive sleep apnea