These patients were ventilated with parameter setting on CMV such as FiO2 > 90%, frequency > 70 breath / min, I: E ratio range from 1: 1 to 2: 1, mean airway pressure 18, 1 ± 5, 21 cmH2O, PIP 25, 8 ± 5, 1 cmH2O, PEEP 6 ± 1, 3 cmH2O.