BACKGROUND: The purpose of this study was to test the hypothesis that a single bolus of 6% hydroxyethyl starch (HES 450/0.7 in lactated electrolyte injection) during initial resuscitation has a differential effect in blunt and penetrating trauma patients. METHODS: Consecutive admissions to the trauma service were reviewed. Patients who died within 24 hours were excluded. Multivariate analysis defined individual predictors for the primary outcomes, acute kidney injury (AKI) and mortality within 90 days. Data were expressed as mean SD, and significance was assessed at p < 0.05. RESULTS: There were 1,410 patients (76% male; mean SD, age 43 18 years; 68% blunt trauma; mean SD Injury Severity Score [ISS] 14 11; AKI, 4.4%; and mortality, 3.4%). HES (0.5-1.5 L) was administered to 216 patients (15.3%). After multiple logistic regression, HES remained a significant independent predictor of AKI after blunt trauma (odds ratio [OR], 2.54; 95% confidence interval [CI], 1.24-5.19; area under the receiver operating characteristic curve [AUROC], 0.809) but not penetrating trauma (OR, 0.90; 95% CI, 0.23-3.60; AUROC, 0.849). In separate logistic regression models, HES was a significant predictor of mortality after blunt trauma (OR, 3.77; 95% CI, 0.91-0.97; AUROC, 0.921) but not penetrating trauma (OR, 0.72; 95% CI, 0.13-3.94; AUROC, 0.904). CONCLUSION: HES is an independent risk factor for AKI and death after blunt, but not penetrating, trauma, which underscores a fundamental difference between these two injury types. (Copyright (C) 2014 by Lippincott Williams & Wilkins)