What is the role of the expiratory pressure (EPAP) in BiPAP?

In BiPAP (Bilevel Positive Airway Pressure) therapy, expiratory pressure (EPAP) plays a crucial role by maintaining a certain level of airway pressure during expiration. This is essential for preventing airway collapse, particularly in patients with obstructive sleep apnea or other conditions where airway stability is compromised. By keeping the airway open through positive pressure, EPAP helps improve ventilation and oxygenation, allowing for more effective gas exchange during the breathing cycle.

The function of EPAP is instrumental in ensuring that the airways remain patent throughout expiration, reducing the risk of airway obstruction and enhancing the overall efficacy of the noninvasive mechanical ventilation strategy. This pressure also assists in promoting better lung mechanics and helps reduce work of breathing, ultimately contributing to patient comfort and successful therapeutic outcomes.