Fig. 1. Lung lavage concentrations of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and macrophage inflammatory protein 2 (MIP-2) after ventilation with different strategies: tidal volume of 7 ml/kg and 3 cm H²O positive end-expiratory pressure (PEEP) (V^T7 PEEP), tidal volume of 15 ml/kg and 3 cm H²O PEEP (V^T15 PEEP), tidal volume of 15 ml/kg and zero PEEP (V^T15 ZEEP), and tidal volume of 40 ml/kg and zero PEEP (V^T40 ZEEP). *  P < 0.05  versus V^T7 PEEP; †  P < 0.05  versus V^T40 ZEEP. BAL = bronchoalveolar alveolar lavage .