Determining Baseline Positive End Expiratory Pressure to Minimize Driving Pressures

Abstract

Background: We sought to determine what our baseline level of positive end expiratory pressure (PEEP) should be set at to minimize ventilator-induced lung injury (VILI). Amato and co-workers determined that a driving pressure (Pd) of 13 cm H₂O or less reduced the incidences of VILI. They determined Pd by subtracting PEEP from plateau pressure (Pplat). Methods: After receiving IRB approval, we first measured Pd, using the inspiratory pause function on the ventilator to obtain a Pplat level, at our standard baseline PEEP of 5 cm H₂O on 66 patients in our Level 1 trauma ICU (TICU). Following an initial analysis of these patients we elevated the baseline PEEP to 8 cm H₂O and measured Pd on 112 patients in the TICU. Patients from both groups were ventilated at 6 mL/kg/PBW in either the AC or PAV ventilation mode. Results: The results of our study showed a significant difference, P < .05 in Pd between 5 and 8 of PEEP. Conclusions: Our data reflects that of others suggesting that a higher level of PEEP may aid in reducing VILI. Following this study our ventilator protocol was changed to an entry PEEP level of 8 cm H₂O.