Table 1.
Respiratory variables at baseline, after lavage injury and after stabilization of either ARDSNet or maximal compliance PEEP (PEEPCmax)
| Baseline | Injury | ARDSNet low-stretch | PEEPCmax | P value (injury vs. baseline) | P value (PEEPCmax vs. ARDSNet low-stretch) | |
|---|---|---|---|---|---|---|
| VT, ml/kg | 8.4 ± 0.4 | 8.1 ± 0.4 | 8.5 ± 0.7 | 8.7 ± 0.5 | 0.522 | 0.302 |
| PEEP, cmH2O | 6 ± 1 | 7 ± 2 | 8 ± 2 | 13 ± 2# | 0.497 | 0.004 |
| RR, min−1 | 27 ± 1 | 26 ± 1 | 25 ± 2 | 25 ± 1 | 0.189 | 0.363 |
| FIO2, % | 33 ± 7 | 50 ± 15 | 47 ± 7 | 43 ± 5 | 0.053 | 0.418 |
| Ppeak, cmH2O | 22 ± 3 | 31 ± 7* | 28 ± 5 | 30 ± 5 | 0.043 | 0.468 |
| Pplateau, cmH2O | 21 ± 3 | 30 ± 7 | 27 ± 5 | 28 ± 4 | 0.248 | 0.538 |
| Raw, cmH2O/L/s | 12 ± 2 | 14 ± 1* | 18 ± 4 | 13 ± 4# | 0.041 | 0.017 |
| Cdyn, ml/cmH2O | 11 ± 0 | 9 ± 2* | 9 ± 2 | 14 ± 3# | 0.049 | 0.007 |
| Driving pressure, cmH2O | 16 ± 2 | 21 ± 5* | 20 ± 5 | 16 ± 3# | 0.049 | 0.004 |
| Transpulmonary pressure, cmH2O | 12 ± 2 | 18 ± 5* | 17 ± 4 | 13 ± 4# | 0.037 | 0.003 |
| pH | 7.4 ± 0.1 | 7.3 ± 0.1 | 7.3 ± 0.1 | 7.4 ± 0.1 | 0.329 | 0.417 |
| PvCO2, mmHg | 46 ± 10 | 46 ± 4 | 48 ± 8 | 43 ± 4 | 0.957 | 0.312 |
| PaO2/FIO2, mmHg | 269 ± 56 | 159 ± 37* | 139 ± 26 | 309 ± 110# | 0.003 | 0.022 |
Variables are expressed as mean ± SD
ARDS acute respiratory distress syndrome, PEEP positive end-expiratory pressure, PEEPCmax maximal compliance PEEP, VT tidal volume, RR respiratory rate, Ppeak peak airway pressure, Pplateau plateau airway pressure, Raw airway resistance, Cdyn dynamic compliance, PvCO2 Venous partial pressure of oxygen, PaO2/FIO2 ratio of arterial partial pressure of oxygen (PaO2) to inspired oxygen fraction (FIO2)
*P < 0.05 injury versus baseline; #P < 0.05 PEEPCmax versus ARDSNet