Compliance changes in a two-hit model of lipopolysaccharide (LPS) and mechanical ventilation. (A) Time course of static compliance in mechanically ventilated mice demonstrating a loss of compliance from high tidal volume (HV_T) ventilation (ANOVA on ranks). (B) Delta static compliance calculated by subtracting final from initial values. Both pretreatment with LPS and tidal volume are significant, and there is a significant interaction (two-way ANOVA). LV_T = low tidal volume; PBS = phosphate-buffered saline. *P < 0.05 versus PBS + LV_T control; †P < 0.05 versus no LPS + LV_T. N = 10 per group. Note that 1 kPa = 7.5 mmHg.