NPPV combines two levels of positive airway pressure with which modality?

Noninvasive positive pressure ventilation (NPPV) typically involves the use of bi-level positive airway pressure (BiPAP) rather than continuous positive airway pressure (CPAP). In NPPV, the two levels of pressure refer to the inspiratory positive airway pressure (IPAP) and the expiratory positive airway pressure (EPAP). This dual pressure setting helps improve ventilation and oxygenation while also reducing the work of breathing in patients who may be experiencing respiratory distress or failure.

The key distinction is that BiPAP provides this variability in pressure, allowing for more support during inhalation compared to exhalation, which facilitates patient's ability to breathe on their own while still receiving assistance. Continuous positive airway pressure, while it offers a constant level of pressure, does not provide the two distinct levels required by NPPV, which is essential for managing certain respiratory conditions effectively.