Table 2 Gas exchange and respiratory mechanics

RR—min⁻¹

25 [20–29]

20 [19–25]

26 [23–29]***

24 [20–27]

30 [24–29]***

VE—L min⁻¹

9.6 [7.7–11.3]

8.4 [6.8–10.2]

9.9 [8–11.0]*

9.2 [8.2–9.9]

10.8 [9.5–11.9]**

FiO₂—%

50 [30–70]

30 [24–37]

60 [40–80]***

60 [40–60]**

52 [40–70]***

PaO₂—mmHg

79 [69–96]

88 [69–129]

74 [63–87]*

74 [71–94]

82 [70–91]

PaO₂/FiO₂—mmHg

183 [120–255]

314 [243–378]

129 [100–188]***

174 [121–242]***

157 [121–208]***

PaCO₂—mmHg

40 [35–47]

36 [32–37]

41 [35–50]*

40 [37–48]

42 [39–46]**

Ventilatory ratio

1.3 [1.6–2]

1.3 [1.1–1.5]

1.8 [1.4–2.3]***

1.8 [1.1–2.2]

1.9 [1.6–2.1]***

Patients with complete airway closure > 5 cmH₂O—n

35 (23.5)

4 (9.8)

10 (17.9)

4 (22.2)

17 (50.0) **^{, #}

AOP in patients with complete airway closure > 5 cmH₂O—cmH₂O

8.5 [7.5–11]

9.5 [6.5–12.5]

9 [7.5–11]

8.5 [7–10]

8.5 [8–10]

PEEP_tot—cmH₂O

6 [5.5–7.5]

5.5 [5–6]

6 [5.5–7.5]

6.5 [5.5–6.5]

7.5 [6–9.5]***, ^{##, $$}

P_Plat—cmH₂O

15 [13–18]

12.5 [11–14.5]

15.5 [13.5–18.5]***

15.5 [14–16.5]*

17 [15–20.5]***

C_RS—mL cmH₂O⁻¹

44 [36–56]

55 [45–73]

41 [31–51]**

41 [36–51]*

43 [35–53]**

C_RS-AOP—mL cmH₂O⁻¹

46 [36–57]

56 [45–73]

41 [31–51]**

41 [36–52]*

43 [36–54]*

DP_RS—cmH₂O

8.5 [7–11]

6.5 [5.5–8.5]

9 [6.5–11.5]***

9.5 [8.5–10]**

9 [7.5–11]**

DP_RS-AOP—cmH₂O

8.5 [6.5–10]

6.5 [5.5–8.5]

9.0 [6.5–11.5]**

9 [7.5–10.0]**

8.5 [7.5–10.5]**

R_RS—cmH₂O L⁻¹ s⁻¹

17 [14–21]

16 [14.5–21]

16.5 [13.5–20]

17 [14–18.5]

18 [14.5–22.5]

ΔP1–P_Plat—cmH₂O

2.1 [1.1–3.4]

1.3 [0.9–2.7]

2.4 [1.3–4.2]

2.3 [1.7–2.9]

2.8 [1.1–5.2]

DP_L—cmH₂O

5 [4–7.5]

4 [3–6]

5.5 [4–8.5]*

6.5 [5.5–8]*

5.5 [4.5–7.5]*

P_{Plat Lung}—cmH₂O

9.5 [7.5–12.5]

7.5 [6–9.5]

10 [8–13]*

11 [9.5–13]*

11 [9–12.5]**

Lung Stress—cmH₂O

10 [7.5–14.5]

8 [4–10.5]

10 [8–14]*

14.5 [13.5–16.5]**

12.5 [9–16]*