Objective The lack of need for immediate renal replacement treatment for military trauma victims suggests that the current policy of restricting operational deployment of those Service personnel with active inflammatory renal disease and significantly impaired renal function, combined with good prehospital care for all trauma casualties, is probably correct. No published estimates of renal function in civilian or military trauma victims in the earliest period following injury have been retrieved. The purpose of the present retrospective study was to assess the renal function of military trauma victims on arrival in the Emergency Department of the field hospital.

Methods The case records of 287 military trauma casualties with severe injury (New Injury Severity Score, NISS≥16) were retrospectively reviewed to assess renal function by calculating estimated glomerular filtration rate (eGFR) using the serum creatine concentration obtained immediately on arrival in the Emergency Department of the field hospitals in Iraq and Afghanistan, 2005–2009. Correlations were attempted between eGFR and other clinical and laboratory variables.

Results Hospital case notes recording management following repatriation were retrieved in 221/287 (77%) cases. None had required immediate renal support in the field. Serum creatine concentration on arrival in the field hospital with demographic data permitting calculation of eGFR was recorded in 158 cases. Median eGFR=76 ml/min/1.73m² (range=43–144). Statistically significant correlations were found among eGFR and pulse rate (r=−0.3, p=0.0002), body temperature (r=0.24, p=0.01) and mean arterial pressure (r=0.2, p=0.02). No statistically significant correlation was found among eGFR and NISS, white cell count, or respiration rate. A stepwise multivariate regression analysis of 106 cases suggested that the best combination of clinical observations to predict renal function were pulse rate and body temperature but the prediction was overoptimistic at lower eGFR values. eGFR was statistically significantly different in those satisfying criteria for systemic inflammatory response syndrome (SIRS; eGFR with SIRS=76 and eGFR without SIRS=86 ml/min/1.73 m²).

Conclusions Prehospital resuscitative measures are effective in maintaining renal function at an adequate level until arrival in the field hospital. The combination of tachycardia and hypothermia predicts lower renal function, variables already employed in the assessment of injury severity. The observations in the present study support restriction of recruitment and operational deployment where renal problems exist.