|  | Baseline | 12 h | 24 h | 36 h | 48 h | p value |
---|---|---|---|---|---|---|---|
Plateau pressure (cmH2O) | LVt | 16.7 ± 2.7 | 14.5 ± 0.5 | 18.2 ± 1.1 | 22.0 ± 1.9 | 22.2 ± 2.0 | 0.0188§ |
APRV | 18.2 ± 2.2 | 22.8 ± 2.5* | 27.0 ± 0.6* | 31.0 ± 0.6* | 34.3 ± 0.9* | ||
Transpulmonary pressure (cmH2O) | LVt | 12.7 ± 3.8 | 9.6 ± 1.7 | 11.2 ± 0.1 | 13.8 ± 1.7 | 14.9 ± 1.9 | 0.1116 |
APRV | 12.7 ± 3.2 | 12.6 ± 1.3 | 16.4 ± 1.5 | 14.6 ± 2.1 | 17.3 ± 2.9 | ||
Pleural pressure (cmH2O) | LVt | 3.9 ± 1.3 | 4.9 ± 1.4 | 6.9 ± 1.1 | 8.2 ± 0.3 | 7.6 ± 0.5 | <0.0001§ |
APRV | 5.5 ± 1.0 | 10.2 ± 1.2* | 10.6 ± 1.2 | 16.1 ± 1.4* | 17.4 ± 3.5* | ||
End-expiratory pressure (set) (cmH2O) | LVt | 5.0 ± 0.0 | 5.0 ± 0.0 | 5.0 ± 0.0 | 6.0 ± 1.0 | 6.6 ± 1.7 | <0.0001§ |
APRV | 0.0 ± 0.0* | 0.0 ± 0.0* | 0.0 ± 0.0* | 0.0 ± 0.0* | 0.0 ± 0.0* | ||
End-expiratory pressure (measured) (cmH2O) | LVt | 5.1 ± 0.1 | 5.0 ± 0.1 | 5.2 ± 0.1 | 6.2 ± 1.2 | 6.6 ± 1.7 | <0.0001§ |
APRV | 5.1 ± 0.1 | 10.7 ± 0.9* | 11.8 ± 0.6* | 14.2 ± 1.1* | 17.8 ± 2.0* | ||
Tidal volume (cc kg−1) | LVt | 10.2 ± 0.1 | 6.0 ± 0.0 | 6.0 ± 0.0 | 5.9 ± 0.0 | 5.6 ± 0.3 | <0.0001§ |
APRV | 10.0 ± 0.1 | 9.7 ± 0.3* | 11.0 ± 0.8* | 12.3 ± 0.6* | 13.3 0.6* | ||
Respiratory system elastance (cmH2O L−1) | LVt | 31.2 ± 7.9 | 43.5 ± 4.2 | 59.8 ± 6.3 | 72.8 ± 8.3 | 76.4 ± 9.4 | <0.0001§ |
APRV | 35.8 ± 6.0 | 34.2 ± 4.8 | 38.5 ± 5.5 | 38.0 ± 5.6* | 33.4 ± 4.6* | ||
Lung elastance (cmH2O L−1) | LVt | 24.4 ± 9.4 | 29.3 ± 6.7 | 36.7 ± 1.6 | 45.7 ± 6.3 | 50.3 ± 8.3 | <0.0001§ |
APRV | 29.7 ± 6.6 | 18.8 ± 2.6 | 23.8 ± 5.1 | 18.8 ± 4.8* | 17.6 ± 5.1* | ||
Chest wall elastance (cmH2O L−1) | LVt | 6.8 ± 1.9 | 14.2 ± 3.9 | 23.1 ± 4.8 | 27.0 ± 2.6 | 26.2 ± 2.9 | 0.0377§ |
APRV | 10.6 ± 1.8 | 15.4 ± 2.3 | 14.7 ± 1.0 | 19.2 ± 1.1* | 15.8 ± 0.5* | ||
FiO2 (%) | LVt | 1.00 ± 0.00 | 0.24 ± 0.03 | 0.27 ± 0.05 | 0.33 ± 0.03 | 0.37 ± 0.07 | <0.0001§ |
APRV | 1.00 ± 0.00 | 0.21 ± 0.00 | 0.21 ± 0.00 | 0.21 ± 0.00* | 0.21 ± 0.00 | ||
PaO2/FiO2 (mmHg) | LVt | 550.4 ± 20.1 | 429.4 ± 36.6 | 411.3 ± 39.2 | 269.6 ± 6.4 | 226.2 ± 17.1 | <0.0001§ |
APRV | 556.8 ± 27.4 | 443.5 ± 29.4 | 416.8 ± 26.5 | 374.6 ± 13.8* | 465.7 ± 66.5* |