Table 2: The ventilatory parameters in the three groups at T1 and T2.

High hypercapnia group ()Low hypercapnia group ()Control group () value

Peak pressure (cmH2O)
 T10.36
 T2#<0.01
Plateau pressure (cmH2O)
 T10.81
 T2#<0.01
Dynamic compliance (ml/cmH2O)
 T10.58
 T2#<0.01

T1 = before operation; T2 = 30 min after pneumoperitoneum. Compared with control group; #compared with low hypercapnia group.