BiPAP / VPAP (Bilevel Positive Airway Pressure)
A PAP device delivering two different pressures: higher during inspiration (IPAP) and lower during expiration (EPAP). Used when CPAP alone cannot resolve flow limitation.
What Is BiPAP / VPAP (Bilevel Positive Airway Pressure)?
Bilevel Positive Airway Pressure (BiPAP) delivers two different pressures: a higher pressure during inspiration (IPAP) and a lower pressure during expiration (EPAP). The difference between IPAP and EPAP is called pressure support, which provides active assistance during inhalation to push air through a narrowed airway.
BiPAP is typically used when CPAP alone cannot adequately resolve flow limitation, when higher pressures are needed for comfort (BiPAP's lower expiratory pressure makes breathing out easier), or when ventilatory support is required for conditions like obesity hypoventilation syndrome. ResMed brands their bilevel devices as VPAP.
BiPAP can be used in spontaneous mode (the machine detects your breaths), timed mode (the machine delivers breaths at a set rate), or ST (Spontaneous-Timed) mode (spontaneous with a backup rate). AirwayLab provides specific BiPAP analysis including trigger delay, cycling metrics, time at IPAP, and pressure support validation from the flow and pressure waveforms.
How AirwayLab Measures This
AirwayLab reads BiPAP settings from STR.edf and computes delivered EPAP/IPAP from the BRP.edf pressure channel using P10/P90 percentiles. The Settings tab shows trigger delay, cycling metrics, time at IPAP, I:E ratio, tidal volume CV, and end-expiratory pressure analysis.
Try it with your dataFrequently Asked Questions
When is BiPAP needed instead of CPAP?
BiPAP is typically prescribed when CPAP cannot adequately resolve flow limitation (the pressure needed is too high for comfort), when the patient has difficulty exhaling against a single high pressure, or when additional ventilatory support is needed for conditions like obesity hypoventilation syndrome.
What is pressure support on BiPAP?
Pressure support is the difference between IPAP (inspiratory pressure) and EPAP (expiratory pressure). For example, with IPAP of 14 cmH2O and EPAP of 10 cmH2O, pressure support is 4 cmH2O. Higher pressure support provides more breathing assistance during inhalation.
Related Terms
From the Blog
Medical Disclaimer
AirwayLab is not a medical device and is not FDA-cleared or CE-marked. It is provided for educational and informational purposes only. The analysis results should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult qualified healthcare providers regarding your sleep therapy and any changes to PAP settings.