Effect of different ventilator strategies on cytokine concentrations in lung lavage of isolated unperfused rat lungs. Four ventilator settings were used: controls (C = normal tidal volume), moderate tidal volume + high PEEP (MVHP), moderate tidal volume + zero PEEP (MVZP), high tidal volume + zero PEEP (HVZP) resulting in the same end-inspiratory distension as MVHP. Major increases in cytokine concentrations were observed with HVZP. Used with permission. From Tremblay et al. .