Table 3. Preoperative laboratory test results among 991 patients operated in São Paulo, Brazil.
| Test | Mean ± SD | % outside reference values | % above reference values | % below reference values |
|---|---|---|---|---|
| Serum sodium | 139.7 ± 4.0 (mEq/l) | 11.3 | 2.0 | 9.3 |
| Serum potassium | 4.4 ± 0.5 (mEq/l) | 13.6 | 10.1 | 3.5 |
| Blood urea | 39.9 ± 18.5 (mg/dl) | 25.3 | 25.3 | 0.0 |
| Serum creatinine | 1.1 ± 0.5 (mg/dl) | 13.2 | 10.9 | 2.3 |
| Prothrombin time | 11.5 ± 1.6 (sec) | 5.1 | 3.0 | 2.1 |
| Platelet count | 260,249 ± 90,154 (units/mm3) | 13.1 | 6.9 | 6.2 |
| Hematocrit | 40.0 ± 5.2 (%) | 41.0 | 1.2 | 39.9 |
| White blood cells | 8.2 ± 2.9 (units x 103/mm3) | 31.4 | 22.0 | 9.4 |
SD = standard deviation.