Table 2 Ventilatory parameters

PIP (cm H₂O)

VCV

12.4 ± 1.1

21.0 ± 1.9

21.5 ± 2.3

20.8 ± 2.3

8.6 [7.4 to 9.9], <  0.0001

9.1 [7.9 to 10.3], <  0.0001

8.4 [7.2 to 9.7], <  0.0001

PCV-VG

12.2 ± 1.5

17.3 ± 2.5

18.3 ± 2.4

18.6 ± 2.8

5.2 [4.0 to 6.4], <  0.0001

6.1 [4.9 to 7.3], <  0.0001

6.4 [5.2 to 7.7], <  0.0001

Mean diff [95% CI]

0.2 [1.1 to 1.4]

3.7 [2.4 to 4.9]

3.2 [2.0 to 4.5]

2.2 [0.9 to 3.4]

P

>  0.9999

<  0.0001

<  0.0001

0.0001

Pmean (cm H₂O)

VCV

6.2 ± 0.9

8.5 ± 1.0

8.5 ± 1.1

8.7 ± 1.0

2.4 [1.7 to 3.0], <  0.0001

2.4 [1.7 to 3.0], <  0.0001

2.5 [1.9 to 3.2], <  0.0001

PCV-VG

6.3 ± 0.9

8.5 ± 1.2

8.5 ± 1.3

8.5 ± 1.2

2.1 [1.5 to 2.8], <  0.0001

2.1 [1.4 to 2.7], <  0.0001

2.1 [1.5 to 2.8], <  0.0001

Mean diff [95% CI]

−0.2 [− 0.8 to 0.4]

0.1 [− 0.6 to 0.6]

0.1 [− 0.6 to 0.7]

0.2 [− 0.4 to 0.9]

P

>  0.9999

>  0.9999

>  0.9999

>  0.9999

Cydn (ml/cm H₂O)

VCV

39.4 ± 3.2

23.0 ± 2.1

22.7 ± 1.8

23.4 ± 2.1

−16.5 [− 18.0 to − 14.9], <  0.0001

−16.7 [− 18.3 to − 15.2], <  0.0001

− 16.0 [− 17.6 to − 14.5], <  0.0001

PCV-VG

40.5 ± 3.9

27.1 ± 2.0

27.0 ± 1.6

26.9 ± 1.7

−13.3 [− 148 to − 11.8], <  0.0001

−13.4 [− 14.9 to − 11.8], <  0.0001

− 13.5 [− 15.1 to − 12.0], <  0.0001

Mean diff [95% CI]

−1.0 [− 2.4 to 0.4]

−4.1 [− 5.6 to − 2.7]

−4.3 [− 5.8 to − 2.9]

−3.5 [− 4.9 to − 2.1]

P

0.3332

<  0.0001

<  0.0001

<  0.0001

RR (breath/min)

VCV

11.9 ± 0.5

13.2 ± 0.5

14.2 ± 0.6

14.0 ± 0.6

1.3 [1.0 to 1.7], <  0.0001

2.3 [2.0 to 2.7], <  0.0001

2.2 [1.8 to 2.5], <  0.0001

PCV-VG

11.9 ± 0.6

13.0 ± 0.5

14.1 ± 0.6

14.0 ± 0.6

1.1 [0.7 to 1.4], <  0.0001

2.1 [1.7 to 2.5], <  0.0001

1.9 [1.6 to 2.3], <  0.0001

Mean diff [95% CI]

−0.0 [− 0.4 to 0.2]

0.2 [−0.1 to 0.5]

0.1 [− 0.2 to 0.4]

0.0 [− 0.3 to 0.4]

P

>  0.9999

0.8655

>  0.9999

>  0.9999

V_T (ml)

VCV

482 ± 16

485 ± 17

480 ± 15

484 ± 18

2.0 [−8.9 to 12.8], >  0.9999

−2.5 [−13.3 to 8.4], >  0.9999

1.0 [−9.8 to 11.9], >  0.9999

PCV-VG

483 ± 23

480 ± 22

479 ± 22

475 ± 20

−4.0 [−14.8 to 6.6], >  0.9999

−4.2 [− 14.9 to 6.5], >  0.9999

− 8.2 [− 18.9 to 2.5], 0.1961

Mean diff [95% CI]

−0.6 [− 11.8 to 10.6]

5.4 [− 5.8 to 16.7]

1.1 [− 10.1 to 12.4]

8.7 [− 2.5 to 19.9]

P

>  0.9999

0.8965

>  0.9999

0.2117

P_ETCO₂ (mmHg)

VCV

32.4 ± 2.9

33.0 ± 2.6

36.2 ± 3.2

38.7 ± 3.1

0.6 [−1.1 to 2.5], >  0.9999

3.8 [1.9 to 5.7], <  0.0001

6.3 [4.4 to 8.1], <  0.0001

PCV-VG

32.2 ± 3.0

33.6 ± 2.9

35.5 ± 3.5

38.3 ± 4.6

1.3 [−0.5 to 3.1], 0.2646

3.2 [1.4 to 5.1], <  0.0001

6.0 [4.1 to 7.8], <  0.0001

Mean diff [95% CI]

0.1 [−1.8 to 2.0]

− 0.5 [−2.5 to 1.4]

0.6 [− 1.2 to 2.6]

0.4 [− 1.5 to 2.3]

P

>  0.9999

>  0.9999

>  0.9999

>  0.9999