Table 3 Respiratory profile parameters for the eight different conditions tested

MV (L/min)

9.9 (8.7–14.4)

8.9 (7.1–10.5)

p = 0.03

13.7 (10.6–18.5)

16.4 (10.7–24.4)

12.9 (11.1–18.5)

*p = 0.001,

p < 0.05 for all the ventilation modalities compared to SB without resistance

p > 0.05 for all pairwise comparisons between PS low, PS high and NAVA

11.1 (10.5–12.1)

13.7 (10.9–18.0)

11.1 (9.9–12.5)

^#p = 0.001

p < 0.05 for all the ventilation modalities compared to SB with resistance

p < 0.05 between PS high and PS low and between PS high and NAVA

RR (br/min)

14.6 (12.5–15.7)

10.9 (8.7–12.0)

p < 0.001

15.5 (12.9–17.7)

15.3 (13.7–16.5)

14.0 (12.1–17.8)

*p = 0.22

12.7 (10.2–13.6)

12.5 (10.6–13.8)

12.1 (10.4–16.5)

^#p = 0.053

VT (L)

0.81 (0.65–1.00)

0.90 (0.70–1.05)

p = 0.54

0.99 (0.79–1.20)

0.99 (0.69–1.71)

0.92 (0.74–1.21)

*p = 0.004

p < 0.05 for all the ventilation modalities compared to SB without resistance.

p > 0.05 for all pairwise comparisons between PS low, PS high and NAVA

0.88 (0.86–1.01)

1.33 (0.96–1.48)

0.90 (0.78–1.04)

^#p = 0.055

Tin (ms)

1.76 (1.48–2.00)

2.41 (1.91–2.67)

p < 0.001

1.54 (1.38–1.78)

1.45 (1.36–1.73)

1.68 (1.29–1.91)

*p = 0.46

1.78 (1.63–2.01)

1.78 (1.62–1.96)

1.91 (1.43–2.15)

^#p = 0.027.

p < 0.05 between SB with resistance and PS low, SB with resistance and PS high and SB with resistance and NAVA

Tiex (ms)

0.17 (0.10–0.22)

0.27 (0.22–0.38)

p < 0.001

0.20 (0.14–0.25)

0.24 (0.11–0.29)

0.24 (0.21–0.31)

*p = 0.23

0.31 (0.21–0.33)

0.41 (0.31–0.64)

0.28 (0.20–0.40)

^#p = 0.039.

p < 0.05 between SB with resistance and PS high, and between PS low and PS high

Ti/Ttot

0.41 (0.40–0.45)

0.44 (0.42–0.47)

p = 0.10

0.41 (0.39–0.44)

0.42 (0.37–0.45)

0.44 (0.41–0.47)

*p = 0.17

0.43 (0.40–0.44)

0.41 (0.39–0.45)

0.44 (0.39–0.45)

^#p = 0.97