Non-operatively managed blunt and penetrating renal trauma: Does early follow up CT scan change management? A systematic review

Background Renal injury accounts for 1–5% of all traumatic injuries. Non-operative management (NOM) of renal trauma has demonstrated higher renal salvage rates and reduced morbidity. Aims The aim of this review is to clarify the indications of early follow up CT scan for adult patients, with NOM, renal trauma, with a view to avoiding unnecessary CT scanning and radiation exposure in this cohort of patients. Methods A systematic search was conducted using PubMed (MEDLINE), Web of Science, Embase, and Cochrane library, with references from relevant articles also evaluated. Inclusion criteria were defined as studies reporting outcomes of patients ≥12 years of age, with NOM, renal trauma and early CT re-imaging. The outcomes of interest were renal complications requiring intervention, specifically collecting system and vascular complications. Results Five studies met the inclusion criteria. In total, 542 patients were included in this analysis; study sizes ranged from 48 to 207 patients. Early re-imaging was performed for 510 patients, including 489 CTs and 31 Ultrasounds (US). Mean time to re-imaging ranged from 1 - 35.9 days. Twenty three patients required intervention following re-imaging, all of which were for injuries grade ≥ 3 and presented with clinical deterioration prior to re-imaging, had a collecting system injury identified on initial CT scan or both. The number needed to re-image, in order to change the management of one patient, was 22. Conclusions Although the findings of this review are based on retrospective data, they suggest routine early re-imaging can be safely omitted for all NOM, renal injuries which remain asymptomatic, with no collecting system injury diagnosed on initial CT, provided appropriate delayed phase imaging is available. Future prospective studies are required to further clarify the indications of early re-imaging, specifically for NOM penetrating injuries, and the appropriate modality and timing of early re-imaging for all NOM renal trauma.