Table 2.
Arterial blood gas analysis, hemoglobin and systemic carbon dioxide and oxygen variables
| Parameters | BL | 3 h | 6 h | 12 h | 18 h | End |
|---|---|---|---|---|---|---|
| pH | 7.48 (7.41–7.53) | 7.46 (7.31–7.52) | 7.45 (7.29–7.54) | 7.44 (7.25–7.58) | 7.44 (7.32–7.56) | 7.41 (7.18–7.59) |
| Bicarbonate (mmol/l) | 27.2 (23.9–29.6) | 26.3 (22.0–29.9) | 26.2 (21.6–30.8) | 26.6 (19.8–30.9) | 26.9 (21.8–31.8) | 26.9 (13.9–33.5) |
| Base excess (mmol/l) | 3.9 (0.1–6.5) | 2.8 (− 2.8 to 6.6) | 2.8 (− 2.8 to 7.4) | 3.0 (− 4.9 to 8.2) | 3.2 (− 2.2 to 8.5) | 2.6 (− 9.0 to 8.7) |
| PaCO2 (mm Hg) | 37.7 (33.1–41.8) | 38.0 (29.7–50.7) | 38.6 (31.3–51.5) | 39.3 (33.3–53.1) | 38.6 (34.0–56.7) | 41.1 (17.7–80.3) |
| PaO2 (mm Hg) | 137 (81–177) | 119 (49–214) | 121 (43–172) | 118 (34–183) | 127 (38–203) | 110 (44–218) |
| SpO2 (%) | 97 (90–100) | 96 (69–100) | 96 (55–99) | 96 (55–98) | 96 (50–97) | 95 (46–98) |
| Arterial hemoglobin (g/dl) | 8.9 (6.3–11.2) | 9.2 (7.0–13.8) | 9.4 (6.4–14.2) | 9.1 (6.6–13.5) | 8.4 (6.6–13.7) | 8.6 (5.2–13.0) |
| CaCO2 (ml/dl) | 56.5 (49.5–61.4) | 54.6 (44.5–62.4) | 54.9 (44.7–63.5) | 55.4 (43.5–64.0) | 57.0 (45.4–66.4) | 56.0 (28.4–73.5) |
| CvCO2 (ml/dl) | 62.3 (47.2–67.2) | 60.0 (51.4–68.3) | 59.5 (51.4–69.2) | 61.1 (52.0–67.9) | 62.0 (52.5–69.4) | 61.9 (43.9–75.1) |
| Cv-aCO2 (ml/dl) | 5.7 (1.9–10.0) | 5.5 (0.1–9.6) | 5.4 (1.0–10.8) | 5.5 (1.8–10.5) | 5.5 (2.3–9.7) | 5.1 (1.6–19.3) |
| Pv-aCO2 (mmHg) | 8.4 (0.9–11.7) | 8.4 (3.1–15.1) | 7.8 (1.7–14.2) | 8.9 (2.9–16.7) | 8.5 (0.5–18.6) | 9.4 (4.6–64.4) |
| CaO2 (ml/dl) | 12.1 (8.7–14.9) | 12.3 (8.2–17.5) | 12.5 (7.0–18.4) | 11.8 (6.6–18.3) | 11.2 (5.3–18.2) | 10.7 (5.3–17.1) |
| CvO2 (ml/dl) | 6.3 (2.9–8.9) | 6.9 (2.1–11.6) | 7.1 (1.0–13.5) | 6.7 (2.7–11.0) | 6.8 (1.5–11.2) | 6.1 (0.8–12.8) |
| Ca-vO2 (ml/l) | 5.6 (4.2–8.1) | 5.7 (3.5–8.1) | 5.2 (2.8–9.2) | 5.2 (2.6–9.0) | 4.4 (3.0–9.6) | 4.6 (2.9–11.8) |
| Cv-aCO2/Ca-vO2 | 1.0 (0.4–1.7) | 1.0 (0.0–1.6) | 1.0 (0.3–1.8) | 1.0 (0.5–1.6) | 1.1 (0.5–2.0) | 1.0 (0.3–3.8) |
| Pv-aCO2/Ca-vO2 (mmHg ml O2/dl) | 1.5 (0.1–2.2) | 1.5 (0.8–2.8) | 1.5 (0.4–2.1) | 1.7 (1.0–2.6) | 1.9 (0.1–2.5) | 2.0 (1.1–6.2) |
Values represent median and range. BL = baseline, End = end of experiment after 24 h of randomization or before death if earlier. PaO2 = arterial oxygen partial pressure, PaCO2 = arterial carbon dioxide partial pressure, SpO2 = peripheral oxygen saturation, CaCO2 = arterial CO2 content, CvCO2 = venous CO2 content, Cv-aCO2 = venous–arterial CO2 content difference, Pv-aCO2 = venous-to-arterial carbon dioxide difference, CaO2 = arterial O2 content, CvO2 = venous O2 content, Ca-vO2 = arterial–venous O2 content difference, Cv-aCO2/Ca-vO2 = venous–arterial CO2 to arterial–venous O2 content difference ratio, Pv-aCO2/Ca-vO2 = ratio between venous-to-arterial carbon dioxide difference and arterial–venous oxygen content difference