Observation vs. early drainage for grade IV blunt renal trauma: a multicenter study.

INTRODUCTION: The aim of this study was to compare observation and early drainage by ureteral stenting in patients with blunt renal trauma and urinary extravasation. MATERIALS AND METHODS: A retrospective national multicenter study was performed including all patients admitted for renal trauma at 17 hospitals between 2005 and 2015. Patients presenting with a urinary extravasation on initial imaging were considered for inclusion. Patients were divided in two groups according to the initial approach: observation vs. early drainage by ureteral stent (within 48 h after admission). The primary endpoint was the persistence of urinary extravasation on follow-up imaging. RESULTS: Out of 1799 patients with renal trauma, 238 were included in the analysis (57 in the early drainage and 181 in the observation group). In the early drainage group, 29 patients had persistent urinary extravasation vs. 77 in the observation group (50.9% vs. 42.5%; p value = 0.27). The rates of secondary upper urinary tract drainage did not differ significantly between the early drainage group (26.4%) and the observation group (16%) (p = 0.14). There were no statistically significant differences between the two groups in terms of secondary nephrectomy (0% vs. 2.8%; p = 0.34), and death from trauma (0% vs. 1.8%; p = 0.99). In multivariate analysis, early drainage remained not statistically associated with persistence of urinary extravasation on follow-up imaging (OR = 1.35; p = 0.36) CONCLUSION: In this multicenter cohort, observation was not different from early drainage in terms of persistent urinary extravasation after grade IV blunt renal trauma. Further randomized controlled prospective trials are needed to confirm these findings.