Fig. 2. ( A ) Microvascular leakage (bronchoalveolar lavage Evans blue absorbance) was significantly less in the groups ventilated with 70% or 100% O2 versus 21% O2(* P < 0.05, one-way analysis of variance, post hoc Student-Neumann-Keuls tests). ( B ) Increasing the percentage of inspired oxygen resulted in a dose-dependent increase in arterial oxygen tension (Pao 2; P < 0.05). ( C ) Increased inspired oxygen was associated with an increased delta alveolar–arterial oxygenation gradient (AaDO2) (final − baseline AaO2; P < 0.05). Data are expressed as mean ± SD ( A ) or as actual data points ( B and C ).