Table 2.
Arterial blood gases at ZEEP (BASELINE), after PEEP = 9 cmH2O and at FINAL
| FLUIDS | PEEP | ZEEP | PEEP 9 | FINAL | |
|---|---|---|---|---|---|
| pHa | NORMO | FAST | 7.24 ± 0.09 | 7.19 ± 0.23 | 7.16 ± 0.09 |
| HIGH | 7.25 ± 0.04 | 7.18 ± 0.08 | 7.17 ± 0.07 | ||
| NORMO | SLOW | 7.23 ± 0.05 | 7.21 ± 0.20 | 7.14 ± 0.08 | |
| HIGH | 7.23 ± 0.06 | 7.13 ± 0.10 | 7.15 ± 0.08 | ||
|
PaO2/FiO2 (mmHg) |
NORMO | FAST | 241 ± 114 | 435 ± 40* | 390 ± 51* |
| HIGH | 232 ± 90 | 365 ± 55* | 425 ± 35* | ||
| NORMO | SLOW | 222 ± 70 | 430 ± 25* | 396 ± 31* | |
| HIGH | 282 ± 89 | 390 ± 95* | 360 ± 55* | ||
|
PaCO2 (mmHg) |
NORMO | FAST | 45 ± 6 | 59 ± 9* | 77 ± 22* |
| HIGH | 48 ± 5 | 58 ± 8* | 62 ± 17 | ||
| NORMO | SLOW | 50 ± 6 | 63 ± 8 | 65 ± 12 | |
| HIGH | 51 ± 5 | 59 ± 10 | 68 ± 14* | ||
|
HCO3− (mEq/L) |
NORMO | FAST | 20 ± 4 | 20 ± 5 | 25 ± 5 |
| HIGH | 22 ± 6 | 22 ± 7 | 23 ± 6 | ||
| NORMO | SLOW | 21 ± 6 | 21 ± 6 | 21 ± 4 | |
| HIGH | 23 ± 7 | 21 ± 7 | 24 ± 7 |
Values are means ± SD of 7 animals/group. NORMO and HIGH: administration of Ringer lactate at 10 mL/kg/h and 30 mL/kg/h, respectively. FAST: abrupt PEEP decrease from 9 to 3 cmH2O. SLOW: gradual PEEP decrease (0.2 cmH2O/min) from 9 to 3 cmH2O
pHa arterial pH, PaO2/FiO2 ratio of partial pressure of oxygen in arterial blood to fraction of inspired oxygen, PaCO2 partial pressure of carbon dioxide, HCO3− bicarbonate
*Significantly different from BASELINE (p < 0.05)