Effect of the EzPAP system on tidal volume and airway pressures in healthy adults

The EzPAP system generates positive inspiratory and expiratory pressures to increase lung volumes, yet limited evidence describes how different flow settings influence its physiological effects. This study examined the impact of EzPAP on tidal volume (VT), minute ventilation (VE), airway pressures, and physiological responses in healthy adults. # Methods A prospective repeated‑measures study was conducted in 26 healthy adults. VT, VE, airway pressures, respiratory rate, perceived exertion, discomfort, and hemodynamic variables were recorded at baseline and during EzPAP use across seven flow settings, flowEzPAP (0-15 L/min). Generalized linear mixed models evaluated the effects of flowEzPAP on all outcomes. # Results Compared to zero flowEzPAP, VT increased with higher flowEzPAP, with a mean difference of 0.35 L at 15 L/min (p < .001). VE decreased, with the greatest mean reduction of 0.84 L/min at 13 L/min (p < .001). Peak inspiratory (PIP), peak expiratory (PEP), and end‑expiratory (PEEP) pressures rose significantly with flowEzPAP, with greatest mean increases of 5.40, 15.06, and 13.33 cmH₂O at 15 L/min (all p < .001). PIP and PEP predicted VT, and all pressures predicted VE (p < .001). Respiratory rate decreased, while exertion and discomfort increased at higher flows. One transient adverse event occurred at the highest flowEzPAP. # Discussion EzPAP produced clinically relevant increases in lung volumes and airway pressures with minimal physiological disturbance in healthy adults. Threshold flowEzPAP settings were identified for achieving therapeutic expiratory pressures. # Conclusion EzPAP safely increased VT and airway pressures in healthy adults, supporting further evaluation in clinical populations with reduced lung volumes or risk of atelectasis.