Fig. 2. Time course of changes in respiratory system compliance of the three groups. C rs= compliance of the respiratory system; PC = pressure-regulated volume control mode with inspiratory time at 20% of total cycle time; VC 20= volume-control mode with inspiratory time at 20% of total cycle time; and VC 50= volume-control mode with inspiratory time at 50% of total cycle time. All values are mean ± SD *Significant difference ( P < 0.05) compared with 0 min in the PC group; **significant difference ( P < 0.05) compared with 0 min in the VC20group; †significant difference ( P < 0.05) compared with the PC group at each measurement point.