Supratherapeutic vancomycin levels after trauma predict acute kidney injury and mortality

IntroductionHigh-dose vancomycin is increasingly prescribed for critically ill trauma patients at risk for methicillin-resistant Staphylococcus aureus pneumonia. Although trauma patients have multiple known risk factors for acute kidney injury (AKI), a link between vancomycin and AKI or mortality has not been established. We hypothesize that high vancomycin trough concentration (VT) after trauma is associated with AKI and increased mortality.MethodsThis was a retrospective analysis from a single institution Level I trauma center. Data were reviewed for all adult trauma patients who were admitted between 2006 and 2010. Patients were included if they received intravenous vancomycin, had serum creatinine levels before and after vancomycin administration, and had at least one recorded VT. Patients were stratified by VT into four groups: VT1 = 0–10 mg/L, VT2 = 10.1–15 mg/L, VT3 = 15.1–20 mg/L, VT4 >20 mg/L. Multivariable logistic regression was performed to determine the association between VT, AKI, and mortality.ResultsOf the 6781 trauma patients reviewed, 263 (3.9%) fit inclusion criteria. Ninety-seven (36.9%) patients developed AKI and 25 (9.5%) died. AKI and mortality increased progressively with VT. Ninety-one patients (34.6%) had troughs >20 mg/L and VT4 was independently associated with AKI (AOR 4.7, P < 0.01) and mortality (AOR 4.8, P = 0.05).ConclusionAKI is common in trauma patients who receive intravenous vancomycin. A supratherapeutic trough level of >20 mg/L is an independent predictor of AKI and mortality in trauma patients.