Table 1.
Case mix, outcome and activity for patients with acute kidney injury during the first 24 hours following admission to intensive care
| Category | Parameter | All patients (n = 17,326) | Oligurica (n = 5,687) | Nonoligurica (n = 10,133) |
| Case mix | Age (years; mean ± SD) | 63.2 ± 15.6 | 63.5 ± 15.0 | 63.1 ± 15.7 |
| Sex (male; n [%]) | 11,511 (66.4) | 3,617 (63.6) | 6,925 (68.3) | |
| Surgical status (n [%]) | ||||
| Nonsurgical | 14,479 (83.7) | 5,005 (88.1) | 8,125 (80.3) | |
| Elective surgery | 961 (5.6) | 187 (3.3) | 717 (7.1) | |
| Emergency surgery | 1,868 (10.8) | 487 (8.6) | 1,280 (12.6) | |
| Serum parameters (mean ± SD) | ||||
| Highest serum creatinine (μmol/l) | 459 ± 232 | 502 ± 244 | 431 ± 216 | |
| Highest serum urea (mmol/l) | 32.2 ± 27.3 | 29.5 ± 15.2 | 33.9 ± 32.3 | |
| Lowest serum albumin (g/l) | 21.3 ± 7.2 | 20.5 ± 6.9 | 21.6 ± 7.2 | |
| Lowest haematocrit (%) | 28.6 ± 6.4 | 28.1 ± 6.3 | 28.8 ± 6.3 | |
| APACHE II (mean ± SD) | ||||
| APSb | 20.2 ± 7.0 | 24.6 ± 6.5 | 17.9 ± 6.1 | |
| Total scoreb | 24.8 ± 7.5 | 29.3 ± 7.0 | 22.4 ± 6.5 | |
| Outcome | Mortality (n [%]) | |||
| CMP unit | 7,508 (43.3) | 3,176 (55.8) | 3,387 (33.4) | |
| Any hospitalc | 9,725 (58.6) | 3,850 (70.3) | 4,770 (49.3) | |
| Activity | Length of stay (days; median [IQR]) | |||
| CMP unit: survivors | 4.1 (1.7–10.3) | 5.7 (2.1–13.2) | 4.0 (1.8–9.8) | |
| CMP unit: nonsurvivors | 2.0 (0.8–6.1) | 1.7 (0.9–5.0) | 3.4 (1.5–8.9) | |
| Any hospitalc: survivors | 31 (17–54) | 38 (24–62) | 29 (16–51) | |
| Any hospitalc: nonsurvivors | 8 (3–20) | 7 (2–18) | 11 (4–23) | |
| Transfers from another ICU (n [%]) | 1,355 (7.8) | 561 (9.9) | 730 (7.2) | |
| Readmissions within hospital stay (n [%]) | 388 (2.2) | 116 (2.0) | 221 (2.2) | |
aOliguria is defined as urine output < 400 ml/24 hours; admitted patients staying less than 8 hours in the ICU excluded. bAPACHE II exclusions: age < 16 years; ICU stay < 8 hours; readmissions within same hospital stay; transfers from another ICU; admissions following coronary artery bypass surgery; and admissions for primary burns. cExcluding readmissions within the same hospital stay. APACHE, Acute Physiology and Chronic Health Evaluation; APS, Acute Physiology Score; CMP, Case Mix Programme; ICU, intensive care unit; IQR, interquartile range; SD, standard deviation.