Posttraumatic Contrast-Induced Acute Kidney Injury: Minimal Consequences or Significant Threat?

Abstract

Recent enthusiasm for the use of iodinated contrast media and progressive adaption of modern imaging techniques suggests an increased risk of contrast-induced acute kidney injury (CIAKI) in trauma patients. We hypothesized that CIAKI incidence would be higher than that previously reported. A 1-year retrospective review of our prospective database was performed. Low-osmolar, nonionic, iodinated intravascular (IV) contrast was used exclusively. CIAKI was defined as serum creatinine>0.5 mg/dL, or >25% increase from baseline within 72 hours of admission. The association between CIAKI and risk factors was explored. Of 3,775 patients, 1,184 (31.4%) received IV contrast and had baseline and follow-up serum creatinine. Median age was 38 years (range, 18-95 years) and median Injury Severity Score (ISS) was 16. A total of 8% of patients had history of diabetes mellitus. CIAKI was identified in 78 (6.6%). One patient required long-term hemodialysis. In univariable analysis, age>65 years (p=0.01), history of diabetes mellitus (p=0.01), initial creatinine>1.5 mg/dL (p=0.01), ISS≥16 (p=0.04), and initial systolic blood pressure<90 mm Hg (p=0.01) were identified as risk factors for CIAKI. Of note, no association with the dose of IV contrast≥250 mL and CIAKI was identified (p=0.95). A multiple logistic regression model identified higher age, male gender, systolic blood pressure<90 mm Hg, and higher ISS as risk factors for CIAKI. In-hospital mortality was significantly higher in the CIAKI group (9.0% vs. 3.2%, p=0.02). After adjusting for covariates, CIAKI was not significantly associated with in-hospital mortality. Current trauma management places patients at substantial risk for CIAKI, and risk stratification can be assessed by common clinical criteria. IV contrast dose alone is not an independent associated risk factor. How these data would be extrapolated to an older cohort remains to be determined.