Airway Pressure Release Ventilation Prevents Ventilator-Induced Lung Injury in Normal Lungs

Abstract

After treatment of arrhythmias, continuous mandatory ventilation (CMV) is the most common therapeutic intervention used in the intensive care unit.¹ Recent studies have shown that up to 25% of patients with normal lungs when placed on mechanical ventilation will develop acute lung injury (ALI). A primary driver of this injury is believed to be the use of higher tidal volumes (Vt), presenting a serious medical problem.^2-5 With limited options for treating established ALI,⁶ strategies for preventing ventilator-induced lung injury (VILI) are needed. Currently, low Vt ventilation is the only strategy used in attempts to reduce the incidence of ALI in normal lungs.⁵ Our group has shown that airway pressure release ventilation (APRV), using our specific settings and applied preemptively,⁷ prevents the development of sepsis-induced ALI and acute respiratory distress syndrome (ARDS).⁸ Because APRV prevented ARDS in these animals at high risk for developing lung injury,⁹ we hypothesized that preemptive application of APRV in normal rats would also prevent ARDS driven by CMV with eupneic Vt in lower-risk, nonseptic rats.