Table 1.
Case mix, outcome and activity for patients admitted to ICUs requiring chronic renal dialysis as compared with other patients
| Parameter | Patients requiring chronic renal dialysis (n = 3,420) |
Patients not requiring chronic renal dialysis (n = 267,552) |
P value | |||
| Case mix | Age (mean [SD]; years) | 57.3 | (15.8) | 59.5 | (19.6) | < 0.001 |
| Male sex (n [%]) | 2,058 | (60.2) | 154,780 | (57.9) | 0.006 | |
| CPR before admission (n [%]) | 466 | (13.6) | 19,535 | (7.3) | < 0.001 | |
| Mechanically ventilated (n [%]) | 2,107 | (61.8) | 167,840 | (63.1) | 0.135 | |
| Highest serum creatinine (mean [SD]; mg per 100 ml/mmol per l]) | 6.5 | (3.2)/575 (283) | 1.5 | (1.3)/133 (115) | < 0.001 | |
| Lowest serum albumin (mean [SD]; g/l) | 22.9 | (7.7) | 23.4 | (8.5) | 0.001 | |
| Lowest haematocrit (%)/haemoglobin (g/dl) (mean [SD]) | 26.9 | (5.9)/9.0 (2.0) | 31.3 | (6.6)/10.4 (2.2) | < 0.001 | |
| APACHE II APS scorea (mean [SD]) | 17.2 | (6.5) | 12.6 | (6.7) | <0.001 | |
| APACHE II scorea (mean [SD]) | 24.7 | (7.0) | 16.6 | (7.3) | < 0.001 | |
| Surgical status (n [%]) | < 0.001 | |||||
| Nonsurgical | 2,282 | (66.7) | 150,350 | (56.2) | ||
| Elective surgery | 592 | (17.3) | 66,017 | (24.7) | ||
| Emergency surgery | 545 | (16.0) | 50,947 | (19.1) | ||
| Number of nonrenal organ system failuresb (n [%]) | < 0.001 | |||||
| None | 1,156 | (33.8) | 107,140 | (40.0) | ||
| 1 | 1,223 | (35.8) | 99,299 | (37.1) | ||
| 2 | 743 | (21.7) | 46,447 | (17.4) | ||
| 3+ | 298 | (8.7) | 14,666 | (5.5) | ||
| Outcome | Mortality in ICU (n [%]) | 898 | (26.3) | 55,547 | (20.8) | < 0.001 |
| Ultimate hospital mortality (n [%]) | 1,379 | (45.3) | 77,869 | (31.2) | < 0.001 | |
| Activity | ICU LOS (median [IQR]; days) | |||||
| Survivors | 1.9 | (0.9–4.2) | 1.8 | (0.9–4.5) | 0.507 | |
| Nonsurvivors | 2.0 | (0.6–6.0) | 1.9 | (0.7–6.1) | 0.843 | |
| Total hospital LOS (median [IQR]; days) | ||||||
| Survivors | 25 | (13–49) | 17 | (9–33) | < 0.001 | |
| Nonsurvivors | 15.5 | (5–35) | 8 | (2–21) | < 0.001 | |
| Transfers from another ICU (n [%]) | 120 | (3.5) | 10,508 | (3.9) | 0.210 | |
| Readmissions within hospital stay (n [%]) | 306 | (9.0) | 12,676 | (4.7) | < 0.001 | |
| Treatment withdrawn (n [%]) | 364 | (10.7) | 26,119 | (9.8) | 0.087 | |
| Destination following discharge (n [%]) | < 0.001 | |||||
| Ward, same hospital | 1,788 | (70.9) | 155,487 | (73.4) | ||
| Recovery, same hospital | 14 | (0.6) | 975 | (0.5) | ||
| ICU, same hospital | 9 | (0.4) | 1,580 | (0.8) | ||
| HDU, same hospital | 295 | (11.7) | 28,695 | (13.6) | ||
| Other intermediate care, same hospital | 156 | (6.2) | 4,573 | (2.2) | ||
| ICU, other hospital | 94 | (3.7) | 10,898 | (5.2) | ||
| HDU, other hospital | 16 | (0.6) | 850 | (0.4) | ||
| Other hospital, not ICU/HDU | 137 | (5.4) | 6,088 | (2.9) | ||
| Normal residence | 12 | (0.5) | 2,662 | (1.3) | ||
aAcute Physiology and Chronic Health Evaluation (APACHE) II exclusions: age < 16 years; intensive care unit (ICU) stay < 8 hours; readmissions within same hospital stay; transfers from another ICU; admissions following coronary artery bypass grafting; and admissions for primary burns. bOrgan system failures assessed physiologically according to the method of Knaus and coworkers [10]. APS, Acute Physiology Score; CPR, cardiopulmonary resuscitation; HDU, high dependency unit; IQR, interquartile range; LOS, length of stay; SD, standard deviation.