High Frequency Oscillation

Introduction:

As had been seen in previous ARDS trials, the PaO2/FiO2 ratio was not predictive of survival, however, prior days on conventional ventilation (CV) (e.g. 2.5 days in survivors versus ≥ 7 days in nonsurvivors) and the oxygenation index (OI = mPaw X FiO2/PaO2) appeared to be predictive (baseline mean OI = 34 in survivors versus OI = 60 in nonsurvivors) of mortality. These findings suggested that earlier intervention in the course of ARDS with HFOV might be more beneficial. In this initial experience with HFOV we attempted to achieve an “open lung” by applying higher mean airway pressure (mPaw) than was used on CV.