Jet ventilation had better gas exchange efficiency than apneic intermittent ventilation: - The mean of SpO2 in JV group was significantly higher than in AIV group (p<0.05), 99.76 ± 0.94; 99.63 ± 1.22% versus 94.2 ± 3.14; 92.95 ± 3.38% after 15 minutes, 30 minutes of ventilation, respectively.