Renal injury in patients with combat trauma: a single center experience

Aim. To evaluate the nature and outcomes of acute kidney injury in patients with combat trauma. Materials and methods. The prospective observational study enrolled 54 patients who had suffered from combat trauma within 2 to 101 days (median 10.5 days; Q1–Q3: 5–21 days) before admission to hospital. All study participants were men. The mean age of patients was 38.9±9.9 years, ranging from 21 to 65 years. All wounded underwent clinical, laboratory and instrumental examination using standard methods for examining patients with combat injuries. Glomerular filtration rate (GFR) was calculated using two equations – CKD-EPI and MDRD. Results. The mean creatinine concentration at the time of hospitalization was 296.6±174.5 μmol/l, urea – 20.9±9.6 mmol/l, GFR (MDRD) – 33.8±24.2 ml/min, GFR (CKD-EPI) – 37.8±27.8 ml/min. At the previous stages of evacuation, the mean creatinine concentration reached 396.7±203.2 μmol/l, urea – 23.0±11.3 mmol/l, GFR (MDRD) – 22.8±17.7 ml/min, GFR (CKD-EPI) – 24.1±19.7 ml/min. Significant correlations were established between the blood creatinine level and: urea (r=0.73; p<0.000001), total protein (r= -0.33; p=0.01), hemoglobin (r= -0.43; p=0.001). The blood concentration of urea correlated with albumin (r= -0.32; p=0.02), platelet count (r= -0.31; p=0.02) and the percentage of neutrophils (r=0.33; p=0.01). The mean duration of follow-up in the hospital was 58.2±35.6 days. During the observation, 9 patients (16.7%) died, 37 patients (68.5%) were discharged or transferred to other hospitals, 8 wounded continue treatment in the hospital (14.8%). During the observation period, the creatinine level decreased from 408.8 to 92.0 μmol/l (p<0.000001), urea – from 18.9 to 6.5 mmol/l (p=0.000001). Creatinine levels normalized in 62% of patients; out of 19 patients with persistently elevated creatinine levels, 6 cases ended in death. Blood urea concentration remained elevated in 32% of cases (5 of them with a fatal outcome). Renal replacement therapy was required in 55.6% of patients. Conclusion. Patients with severe combat trauma often develop acute kidney injury – prerenal (caused mainly by traumatic shock) or renal. In most cases, this kidney injury is reversible.