Haemodialysis for post-traumatic acute renal failure - factors predicting outcome.

BACKGROUND Post-traumatic acute renal failure requiring renal replacement therapy in an intensive care unit (ICU) is associated with high mortality. OBJECTIVE To assess indicators of improved survival. METHODS This was a retrospective cohort study of 64 consecutive trauma patients (penetrating and blunt trauma and burns) who underwent haemodialysis (HD) over a period of 5 years. Information on pre-hospital and in-hospital resuscitation, trauma scores and physiological scores and daily ICU records were collected. The majority of the patients were dialysed with continuous venovenous haemofiltration in the early years of the study and later with sustained low-efficiency dialysis. RESULTS Of the 64 patients 47 died, giving an overall mortality rate of 73%. Mortality was highest in the burns patients (84%). Survival in all patients, irrespective of injury, was unrelated to the Revised Trauma Score, Injury Severity Score, Acute Physiology and Chronic Health Evaluation Score or Trauma Injury Severity Score. The duration of HD did not differ significantly between the three trauma groups, and age was not a significant predictor of survival. Patients who were polyuric at the time of the initiation of HD had a lower mortality rate than those who were oliguric, anuric or normouric, although this did not reach statistical significance (p=0.09). CONCLUSIONS Acute renal failure in trauma patients is associated with a low survival rate. Controversial conclusions have been presented in the literature. In this study, none of the parameters previously reported to affect survival proved to be valid, although the number of patients was comparable with those in other studies. Since understanding of the predictors and course of renal failure in trauma patients is still at an early stage, there is a need for multicentre prospective studies.