Fig. 1.
Microbiota depletion prior to mechanical ventilation aggravated high tidal volume (HTV) ventilation-induced worsening of lung function. Mice received antibiotic broad-spectrum therapy (ATB). Control (Ctrl) mice did not receive antibiotic treatment. Ventilator-induced lung injury (VILI) was induced 3 days after completing antibiotic treatment protocol by (HTV) ventilation (34 ml/kg; positive end-expiratory pressure = 2 cmH2O, 4 h). Additional groups of mice were ventilated with low tidal volume (LTV). a Dynamic elastance (E) was measured in 5-min intervals during ventilation. Baseline was set to 30 min and values were normalized to baseline. b-c Static compliance (Cstat) was measured at the start (b) and after 4 h of ventilation (c). Values are given as mean ± SD (a) or mean and SD (b-c). In a n = 11 (LTV ctrl) or n = 7 (HTV ctrl, HTV ATB) or n = 6 (LTV ATB); in b n = 11 (LTV ctrl, HTV ctrl, HTV ATB) or n = 10 (LTV ATB); c n = 11 (HTV ctrl) or n = 10 (LTV ctrl, LTV ATB, HTV ATB). Analysis was by two-way repeated measures analysis of variance (ANOVA)/Tukey’s multiple comparison test (a) or by two-way ANOVA/Tukey’s multiple comparison test (b-c). **P < 0.01, ***P < 0.001, ****P < 0.0001