Table 2.
Blood gas and pulse-oximetry measurements.
| Measurement | Arterial | Venous | Pulse-oximetry | Coefficient |
|---|---|---|---|---|
| On admission (n=34) | ||||
| pH | 7.27±0.1 | 7.24±0.09 | 0.79 | |
| CO2 (mmHg) | 51.6±15.2 | 56.8±17.6 | 0.70 | |
| Bicarbonate (mEq/l) | 24.4±4.3 | 26.3±4.9 | 0.81 | |
| Base excess | −2.2±5 | −2.4±4.6 | 0.90 | |
| Oxygen saturation | 82.4±11.5 | – | 81.4±11.5 | 0.87 |
| PaO2/FiO2 (mmHg) | 140.9±67 | – | ||
| Overall (n=178) | ||||
| pH | 7.35±0.09 | 7.32±0.09 | 0.92 | |
| CO2 (mmHg) | 46.1±11 | 51.2±13.2 | 0.86 | |
| Bicarbonate (mEq/l) | 25.3±4.8 | 26.3±4.7 | 0.84 | |
| Base excess | −0.05±4.8 | −0.11±4.8 | 0.90 | |
| Oxygen saturation | 94.2±8.4 | – | 93.1±9.1 | 0.83 |
Values are mean±SD. Coefficient, Pearson correlation coefficient; FiO2, fraction of inspired oxygen.