Comparative Study between Airway Pressure Release Ventilation and Biphasic Positive Airway Pressure Ventilation for Patients with Acute Respiratory Distress Syndrome : A Randomized Controlled Trial

Abstract

Background: Severe hypoxemia, decreased respiratory system compliance, and extensive inflammatory pulmonary infiltrates are the hallmarks of acute respiratory distress syndrome (ARDS), a potentially fatal type of acute lung damage that commonly requires mechanical ventilation. The best ventilator strategies for ARDS are still being researched; despite advancements in ventilatory control. Pressure-controlled ventilation modes such as biphasic positive airway pressure (BiPAP) and airway pressure release ventilation (APRV), are frequently used in clinical practice and can affect oxygenation, respiratory mechanics, and mechanical ventilation duration through a variety of physiological mechanisms.

Aim: To compare the effects of APRV and BiPAP on oxygenation , respiratory mechanics, and clinical outcomes in ARDS patients.

Methods: Between February 2024 and March 2025, fifty adult patients with ARDS who were admitted to the ICU and received mechanical ventilation, were randomly assigned to two groups,  Group A patients were managed by APRV mode and Group B patients were managed by BiPAP mode.

Results: No statistically significant difference between the studied groups regarding age or sex. Hemodynamic parameters,(PaO2/FiO2) and PaCO2 remained comparable throughout the study period. No statistical significant difference between two groups regarding baseline respiratory mechanics, then mean airway pressure became higher in APRV group throughout further study time points, but the differences were statistically significant only at days 1 and 3. Patients in the APRV group required significantly higher doses of fentanyl and midazolam compared to those in the BiPAP group(p < 0.05) on days 1 and 3. By Days 5 and 7, the sedation requirements decreased in both groups, with no statistically significant differences observed, indicating a convergence in patient comfort and ventilator synchrony over time. No statistical significant difference between the studied groups regarding clinical outcomes. Conclusion: compared with BiPAP, APRV didn't improve oxygenation, respiratory mechanics , ventilator-free days or other clinical outcomes in ARDS patients.