Lower extremity CT angiograms and their effect on kidney function in orthopedic trauma patients.

Abstract Objectives To evaluate the frequency of unindicated CT Angiograms (CTAs) obtained at our institution and the association between contrast-induced nephropathy (CIN) and decreased glomerular filtration rate (GFR). Design Retrospective case series Setting Academic Level 1 trauma center Patients/participants Patients aged 18 years and older with CTAs following lower-extremity (LE) trauma between 2010-2018. Intervention CTAs performed in 257 LEs and corresponding pre- and post-contrast renal function labs in these LE trauma patients. Main outcome measurements The primary outcome was vascular injury requiring intervention. Secondary outcomes were CIN and the association of CIN with decreased GFR and injury severity score (ISS). Results There was no indication (no hard signs of vascular injury, ABI>0.9) for CTA in 121 patients (61%) of the total 199 patients. Of the 78 patients with signs of vascular injury or ABI 60ml/min (p=0.001). Rate of CIN did not correlate with Injury Severity Score (ISS). Conclusions CTAs are obtained more often than indicated and initial GFR Level of Evidence Level IV