Table 1 General, physiologic and injury severity characteristics of the patients in the overall population and in both subgroups of acute kidney injury (AKI) severity
Characteristics | Whole cohort | No early AKI or AKI stage R | Early AKI stage I or F | p value |
|---|---|---|---|---|
n = 3111 | n = 2934 | n = 177 |  | |
General characteristics | ||||
 Age, years | 38 ± 18 | 38 ± 17 | 39 ± 17 | 0.58 |
 Male sex, n (%) | 2428 (78.0) | 2284 (77.8) | 144 (81.3) | 0.27 |
Direct transfer to trauma center, n (%) | 2589 (83.2) | 2441 (83.2) | 148 (83.6) | 0.70 |
 SAPS II | 21 [11–38] | 20 [11–36] | 47 [31–65] | <  0.001 |
 SOFA 24 h | 2 [0–6] | 1 [0–6] | 9 [5–13] | <  0.001 |
 ISS | 14 (9–25) | 13 [8–24] | 33 [21–41] | <  0.001 |
 Head and neck AIS | 1 [0–3] | 0 [0–3] | 2 [0–3] | 0.02 |
 Abdomen AIS | 0 [0–2] | 0 [0–2] | 2 [0–3] | <  0.001 |
 Thorax AIS | 0 [0–3] | 0 [0–3] | 3 [2–4] | <  0.001 |
 Extremities and pelvis AIS | 1 [0–3] | 1 [0–2] | 2 [0–3] | <  0.001 |
Blunt trauma, n (%) | 2835 (91.1) | 2668 (90.9) | 167 (94.3) | 0.11 |
 MVA, n (%) | 652 (21) | 610 (20.8) | 42 (23.7) | – |
 Motorbike, n (%) | 741 (23.8) | 705 (24) | 36 (20.3) | – |
 Fall, n (%) | 890 (28.6) | 831 (28.3) | 59 (33.3) | – |
 Pedestrian, bicycle, n (%) | 362 (11.6) | 338 (11.5) | 24 (13.6) | – |
 Other, n (%) | 190 (6.1) | 184 (6.3) | 6 (3.4) | – |
Penetrating trauma, n (%) | 276 (9) | 266 (9) | 10 (6) | 0.11 |
 Gunshot wound, n (%) | 87 | 82 | 5 | – |
 Stab wound, n (%) | 189 | 184 | 5 | – |
 Renal trauma, n (%) | 48 (1.5) | 33 (1.1) | 15 (8.5) | <  0.001 |
Trauma brain injury, n (%) | 950 (31) | 879 (30) | 71 (40) | 0.006 |
TRISS | 0.98 [0.90–0.99] | 0.98 [0.92–0.99] | 0.84 [0.38–0.96] | <  0.001 |
Prehospital characteristics | ||||
 Delay between trauma and hospital admission, min | 77 [55–110] | 75 [55–106] | 90 [65–120] | <  0.001 |
 GCS | 15 (12–15) | 15 (13–15) | 14 (5–15) | <  0.001 |
 Minimum SAP, mmHg | 115 [100–130] | 116 [100–130] | 87 [70–111] | <  0.001 |
 Minimum DAP, mmHg | 70 [58–80] | 70 [59–80] | 50 [40–69] | <  0.001 |
 Mean AP, mmHg | 84 [70–95] | 85 [73–95] | 62 [52–82] | <  0.001 |
 Maximum HR, bpm | 93 [80–110] | 91 [80–109] | 110 [90–130] | <  0.001 |
 Minimum SpO2, % | 100 [98–100] | 98 [96–100] | 95 [88–98] | <  0.001 |
 Use of vasopressors, n (%) | 369 (11.9) | 304 (10.4) | 65 (36.7) | <  0.001 |
Hospital admission | ||||
 SAP, mmHg | 124 [108–139] | 124 [109–139] | 102 [78–132] | <  0.001 |
 DAP, mmHg | 72 [61–83] | 72 [61–83] | 59 [45–79] | <  0.001 |
 pH | 7.36 [7.30–7.40] | 7.36 [7.31–7.40] | 7.26 [7.08–7.33] | <  0.001 |
 Lactate, mM | 2 [1.2–3] | 1.9 [1.1–3] | 4.0 [2.6–8.0] | <  0.001 |
 Hemoglobin, g.dL−1 | 13 [11.4–14.3] | 13 [11.5–14.4] | 10.4 [7.8–12.3] | <  0.001 |
 Fibrinogen, g.L− 1 | 2.3 [1.8–2.7] | 2.3 [1.9–2.8] | 1.6 [0.9–2.2] | <  0.001 |
 Mechanical ventilation at day 1, n (%) | 1550 (49.8) | 1397 (47.6) | 153 (86.4) | <  0.001 |
 Surgery day 1, n (%) | 2370 (76.2) | 2231 (76) | 139 (78.5) | 0.4 |
 Interventional radiology procedure, n (%) | 146 (4.7) | 118 (4) | 28 (15.8) | <  0.001 |
Transfusion | ||||
 Hemorrhagic shock, n (%) | 355 (11.4) | 266 (9.1) | 89 (50.3) | <  0.001 |
 RBC transfusion, U | 0 [0–2] | 0 [0–2] | 5 [0–12] | <  0.001 |
 FFP transfusion, U | 0 [0–0] | 0 [0–0] | 3 [0–8] | <  0.001 |
 Platelets transfusion, U | 0 [0–0] | 0 [0–0] | 0 [0–2] | <  0.001 |
Outcomes during hospital stay | ||||
 ICU length of stay, days | 4 [2–12] | 4 [2–11] | 10 [4–24] | <  0.001 |
 Hospital length of stay, days | 10 [4–23] | 10 [4–22] | 21 [4–38] | <  0.001 |
 Predicted mortality, n (%) | 367 (11.8) | 310 (10.6) | 57 (32.2) | – |
 Mortality, n (%) | 335 (10.8) | 268 (9.1) | 67 (37.9) | <  0.001 |