Total and differential cell count in bronchoalveolar lavage from all groups for right (A) and left (B) lung at the end of experiment. Dotted lines represent baseline values from five healthy mice. Data are mean ± SD. Both total cell number and PMN number are significantly higher in HCl-VILI25 (n 8) compared with the other groups (HCl-SB n 14; HCl-VILI15n 8; VILI25n 8). Groups are: HCl-VILI15 and HCl-VILI25, which were instilled in the right bronchus with HCl and subjected to mechanical ventilation, with tidal volume of 15 or 25 ml/kg for 7 h; HCl-SB that was instilled with HCl in right bronchus and left spontaneous breathing for 7 h; VILI25 that was only ventilated with tidal volume of 25 ml/kg for 7 h. *P < 0.05. BAL = bronchoalveolar lavage; HCl = hydrochloric acid; Mφ = macrophages; PMN = polymorphonuclear cells; VILI = ventilator-induced lung injury.
