Pressure Release Ventilation Compared to Lung Protective Ventilation in Moderate and Severe ARDS

Acute respiratory distress syndrome (ARDS) is a severe form of acute respiratory failurecharacterized by impaired oxygenation and bilateral pulmonary abnormalities. Mechanicalventilation is a cornerstone of supportive treatment for patients with moderate to severeARDS.This prospective randomized controlled study compares airway pressure release ventilation(APRV) with conventional low‐tidal‐volume ventilation (LTV) in patients with moderate tosevere ARDS. Eligible patients are randomly allocated in a 1:1 ratio to receive eitherAPRV or LTV according to a predefined ventilation protocol.In the LTV group, ventilation is provided using a lung‐protective strategy with tidalvolumes targeted according to predicted body weight and limitation of plateau pressure.In the APRV group, ventilation is delivered using two airway pressure levels withprolonged high‐pressure periods and brief release periods. APRV settings areindividualized according to oxygenation, ventilation, respiratory mechanics, clinicalresponse, and hemodynamic tolerance. Release tidal volume, minute ventilation, andrespiratory‐system compliance are monitored during APRV.Patients in both groups undergo daily assessment for readiness for ventilator weaning.Once predefined weaning criteria are met, patients undergo a standardized spontaneousbreathing trial using the same procedure in both groups. Patients who successfullycomplete the trial are assessed for extubation according to predefined clinical criteria.The primary outcome is successful extubation, defined as liberation from invasivemechanical ventilation without the need for reintubation within 72 hours afterextubation. Secondary outcomes include time to successful extubation, duration ofmechanical ventilation, change in the PaO₂/FiO₂ ratio during the first 7 days, ICU lengthof stay, and hospital length of stay. Safety outcomes include all‐cause mortality andbarotrauma.