Fig. 3. Effect of positive end expiratory pressure (PEEP) on targeted (T; white column ) versus delivered (D; gray column ) tidal volumes during adaptive support ventilation (ASV). In general, as PEEP increased, both T and D decreased. At PEEP of 16 cm H2O, D was significantly lower than T in the 80-kg group. All data are medians (25th–75th, min-max) with outliers. * P < 0.05. 8 = PEEP of 8 cm H2O; 12 = PEEP of 12 cm H2O; 16 = PEEP of 16 cm H2O.