Variable positive airway pressure, or VPAP (also known as Bilevel positive airway pressure, or BiPAP®) is a method of respiratory ventilation used primarily in the treatment of sleep apnea and various lung diseases, including emphysema. Unlike continuous positive airway pressure (CPAP), VPAP uses an electronic circuit to monitor the patient's breathing, and provides two different pressures, a higher one during inhalation (IPAP) and a lower pressure during exhalation (EPAP). This system is more expensive, and is sometimes used with patients who have a higher than average CPAP pressure and/or who find breathing out against an increased pressure to be uncomfortable or disruptive to their sleep. It can also have a setting to regularly provide ventilation in patients who are unable to regulate their own breathing well. This is used instead of endotracheal intubation in very selected cases and can be used at home too.

EPAP and IPAP settings are determined by the abnormalities requiring correction. In hypoxia, a high EPAP guarantees alveolar ventilation in hypercapnia, a high IPAP gives more volume for diffusion.

NOTE: BiPAP® is a registered trademark of Respironics, Inc.

Medical equipment | Pulmonology