Parameters | Supine (n.20) | Recruitment (n.20) | Prone (n.20) | P value |
---|---|---|---|---|
Respiratory mechanics | ||||
 Respiratory system compliance (ml/cmH2O) | 38.5 (28.5–48.0) | 32.0 (27.0–45.0) | 37.0 (31.0–48.5) | 0.377 |
 Respiratory system driving pressure (cmH2O) | 13.0 (10.0–16.0) | 25.0 (23.0–25.0)a | 13.5 (9.8–16.0)b |  < 0.001 |
 Plateau pressure (cmH2O) | 24.0 (20.0–27.0) | 35.0 (35.0–35.0)a | 24.0 (21.0–26.3)b |  < 0.001 |
 Tidal volume (ml/kg) | 6.7 (6.4–7.0) | 11.2 (9.5–14.9)a | 6.6 (6.1–6.9)b |  < 0.001 |
 Mechanical respiratory rate (breaths/min) | 22.0 (20.0–24.3) | 10.0 (10.0–10.0)a | 21.0 (20.0–24.3)b |  < 0.001 |
Arterial blood gases | ||||
 PaO2/FiO2 (mmHg) | 111.0 (80.3–139.0) | 114.0 (95.5–189.0)c | 156.0 (139.0–204.0)a,d |  < 0.001 |
 PaCO2 (mmHg) | 57.0 (44.0–68.3) | 51.0 (43.5–56.0)a | 50.5 (42.8–61.0)e |  < 0.001 |
 pH | 7.36 (7.28–7.39) | 7.39 (7.34–7.44)a | 7.37 (7.31–7.43)f |  < 0.001 |
Hemodynamics | ||||
 Mean arterial pressure (mmHg) | 88.0 (74.0–93.3) | 80.0 (72.5–87.0) | 82.5 (79.8–88.5) | 0.264 |
 Heart rate (beats/min) | 81.5 (60.0–101.0) | 77.5 (60.8–104.0) | 81.5 (68.5–101.0) | 0.499 |