Wet-to-dry ratio measured after one hour of mechanical ventilation. Animals were randomly assigned to hypovolemia (HYPO), normovolemia (NORMO) or hypervolemia (HYPER) with recruitment maneuver (RM-CPAP) or not (NR). Values are mean ± standard error of the mean of six rats in each group. †Significantly different from NR (P < 0.05). **Significantly different from HYPO-NR (P < 0.05). ‡Significantly different from HYPO-RM-CPAP (P < 0.05). #Significantly different from NORMO-NR (P < 0.05). §Significantly different from NORMO-RM-CPAP (P < 0.05).