Does routine repeat imaging for blunt high-grade renal trauma lead to unnecessary interventions?

BACKGROUND: Most high-grade renal injuries with urinary extravasation (UE) may be managed conservatively without intervention. For such patients, the American Urological Association Urotrauma guidelines recommend repeat imaging within 48 to 72 hours of injury. We sought to examine whether routine, proactive follow-up renal imaging was associated with need for urologic intervention or risk of complications.

METHODS: Patients treated to an urban level 1 trauma center for a five-state region, between 2005 and 2017 were identified by International Classification of Diseases, Ninth Revision and Tenth Revision, codes from a prospectively collected institutional trauma registry. Individual patient charts and imaging were reviewed to identify all patients with American Association for the Surgery of Trauma grade IV renal injuries. Those with UE were included, and patients with penetrating trauma, immediate urologic surgery, or in-hospital mortality were excluded.

RESULTS: Of 342 patients with grade IV injuries, 108 (32%) met the inclusion criteria. Urologic intervention was performed in 23% (25 of 108 patients) including endoscopic procedure (24 of 108 patients) and nephrectomy (1 of 108 patients). Repeat imaging was performed within 48 to 72 hours after initial imaging in 65% (70 to 108 patients). Patients who underwent routine reimaging had a higher rate of undergoing subsequent urologic procedure (31.4% vs. 7.1%, p = 0.008). For patients with reimaging who underwent a procedure, 18% (4 of 22 patients) were symptomatic, while all nonroutinely reimaged patients who underwent a procedure were symptomatic (3 of 3 patients). Patients who received routine repeat imaging had a higher mean number of abdominal computed tomography scans during their admission (2.5 vs. 1.7, p < 0.001), while the complication rate was similar between groups.

CONCLUSIONS: Patients with grade IV renal lacerations with UE from blunt trauma who received routine repeat imaging were more likely to undergo an operation in the absence of symptoms and received more radiation during their hospital stay. Forgoing repeat imaging was not associated with an increase in urological complications. These data suggest that, in the absence of signs/symptoms, repeat imaging may be avoidable.

LEVEL OF EVIDENCE: Therapeutic/care management, level IV.