Table 1.
Optimum PEEP as determined by a decremental PEEP titration optimizing each of the listed titration targets (A). Optimal titration target value achieved in each condition (B)
| Titration target | Supine low | Supine high | Prone low | Prone high |
|---|---|---|---|---|
| (A) | ||||
| CLUNG | 11.0 (4.2)*‡ | 17.3 (4.3)††† | 12.8 (2.4)‡‡ | 16.7 (2.1) |
| PD and CRS | 10.8 (3.3)*‡‡‡ | 18.8 (2.0)† | 13.0 (2.3)‡‡ | 16.7 (2.1) |
| CCW | 11.0 (3.6)**‡ | 19.0 (2.0)†† | 12.3 (5.0)‡ | 14.3 (3.7) |
| EEPTP | 11.0 (2.5)***‡ | 16.5 (2.8)†† | 11.3 (4.3) | 14.8 (3.6) |
| FRC | 18.3 (2.4)* | 19.5 (1.2)†††‡‡ | 18.3 (1.5) | 19.4 (1.2) |
| PAO2:FIO2 | 17.8 (2.3) | 17.5 (2.5) | 17.8 (2.3) | 17.3 (3.4) |
| CO | 6.3 (2.0)***†‡‡‡ | 6.3 (3.0)††† | 7.0 (2.3)‡‡ | 9.1 (4.5) |
| (B) | ||||
| CLUNG (ml/cmH2O) | 47.7 (11.3)*† | 39.6 (12.9)† | 62.7 (17.8)‡ | 57.2 (21.3) |
| PD (cmH2O) | 14.3 (2.9)*†‡ | 17.0 (3.8) | 12.6 (2.5) | 14.6 (2.8) |
| CRS (ml/cmH2O) | 34.6 (6.6)† | 29.4 (6.3)†‡ | 40.8 (10.1) | 34.4 (6.6) |
| CCW (ml/cmH2O) | 196.0 (54.2)*‡ | 148.7 (36.3)† | 145.0 (59.8) | 118.1 (33.1) |
| FRC (ml) | 1335 (360)* | 693 (161)†‡ | 1277 (374) | 970 (256) |
| PAO2:FIO2 | 442 (130) | 249 (139) | 454 (130) | 386.0 (147.2) |
| CO (L/min) | 3.7 (0.7)* | 3.7 (0.7)†‡ | 3.5 (0.5)‡ | 3.8 (0.5) |
Descriptive statistics are shown as mean ± SD. Supine low represents supine position and normal IAP. Supine high represents supine position and IAH. Prone positions are represented similarly
CLUNG lung compliance, PD driving pressure, CRS respiratory system compliance, CCW chest wall compliance, FRC functional residual capacity, CO cardiac output
*p < .05 vs. supine high, **p < .001 vs. supine high, ***p < .0001 vs. supine high, †p < .05 vs. prone low, ††p < .001 vs. prone low, †††p < .0001 vs. prone low, ‡p < .05 vs. prone high, ‡‡p < .001 vs. prone high, ‡‡‡p < .0001 vs. prone high