Table 3 Respiratory mechanics, gas exchange and outcome of the patients divided according to lower or higher airway driving pressure at PEEP 15 cmH₂O

Airway driving pressure (cmH₂O)

13.2 [11.2–16.9]

11.9 [10.2–13.0]

18.0 [16.6–19.9]

<0.001

Transpulmonary driving pressure (cmH₂O)

9.5 [7.8–12.2]

8.4 [6.6–9.7]

13.1 [10.4–15.5]

<0.001

End-inspiratory airway plateau pressure (cmH₂O)

28.4 [25.8–31.3]

26.7 [24.8–28.2]

32.9 [30.8–35.1]

<0.001

Lung stress (cmH₂O)

20.7 [17.9–23.1]

19.3 [16.8–21.7]

23.9 [20.8–26.2]

<0.001

Respiratory system elastance (cmH₂O/L)

26.3 [21.2–32.2]

22.8 [19.5–26.6]

34.2 [29.6–41.9]

<0.001

Lung elastance (cmH₂O/L)

18.7 [14.5–24.2]

16.7 [13.1–19.7]

24.6 [19.5–31.3]

<0.001

Chest wall elastance (cmH₂O/L)

7.0 [4.8–10.3]

6.2 [4.6–8.2]

10.2 [5.9–12.3]

<0.001

PaCO₂ (mmHg)^a

45 [40.2–50.4]

43.8 [39.0–49]

46.8 [41.9–53.2]

0.039

PaO₂/FiO₂ ratio^a

178 [137–237]

175 [136–230]

187 [146–257]

0.314

ICU mortality N (%)

48 (32.0)

28 (28.9)

20 (37.7)

0.352