Risk and benefit of intravenous contrast in trauma patients with an elevated serum creatinine.

Objective: Assess if the benefits outweigh the risks of intravenous (iv) contrast in trauma patients who present with an elevated serum creatinine (Cr).

Background: Radiologic investigations with iv contrast are often used in trauma patients to rapidly assess for life threatening injuries. However, contrast nephropathy (CNP) is associated with increased morbidity and mortality. This poses a dilemma for the physician who must weigh the risks and benefits of proceeding with iv contrast versus the risks of missed injuries/delayed diagnosis.

Methods: A 2 year (2002-2003) retrospective chart review of all trauma patients presenting with an elevated Cr(> or =1.3 mg/dL or > or =115 micromol/L). Results are mean +/- sd (p < 0.05 significant).

Results: Ninety-five patients (age 51 +/- 23 years; ISS 31.7 +/- 15.6; hospital stay 29 +/- 32 days; mortality 9%) presented with a Cr > or = 1.3 mg/dL (31 with Cr > or =1.7; 3 dialysis dependent). Fifty-six (59%) were given iv contrast (C+), of which only 2 (3%) had a transient rise of 25% in Cr within 48 hours versus 6 (16%) patients not exposed to contrast (C-). No C+ patient developed CNP requiring longterm dialysis. Of the 56 undergoing C+ tests, 16 had injuries requiring urgent intervention identified; 16 had injuries that were managed nonoperatively, and 24 had serious injuries ruled out. Of the 39 C- patients, 9 had indeterminate CT's; 2 had missed injuries; and 2 had no intraabdominal injuries found at celiotomy.

Conclusion: This study suggests the benefits may outweight the risks for proceeding prn with iv contrast in trauma patients with an elevated creatinine. A larger study is needed to confirm these findings.