Routine follow-up imaging has limited advantage in the non-operative management of blunt splenic injury in adult patients

Abstract Background : To date, limited evidence exists regarding follow-up imaging during the non-operative management (NOM) of blunt splenic injury (BSI), especially concerning ultrasound as first-line imaging modality. The aim of this study was to investigate the incidence and time to failure of NOM as well as to evaluate the relevance of follow-up imaging. Methods : All adult patients with BSI admitted to our level I trauma center, including two associated hospitals, between 01/01/2010 and 31/12/2017 were retrospectively analyzed. Demographic data, comorbidities, injury pattern, trauma mechanism, Injury Severity Score, splenic injury grade and free intra-abdominal fluid were reviewed. Additional analysis of indication, frequency, modality, results and consequences of follow-up imaging was performed. Risk factors for failure of NOM were evaluated using fisher's exact test. Results : A total of 122 patients with a mean age of 43.8 ± 20.7 years (16-84 years) met inclusion criteria. Twenty patients (16.4%) underwent immediate intervention. One-hundred-and-two patients (83.6%) were treated by NOM. Failure of NOM occurred in 4 patients (3.9%). Failure was significantly associated with active bleeding (3 of 4 [75%] failures vs. 8 of 98 [8.2%] non-failures, OR 33.75, 95% CI 3.1, 363.2, p = 0.004), and liver cirrhosis (2 of 4 [50%] failures vs. 0 of 98 [0%] non-failures, OR 197, 95% CI 7.4, 5265.1, p = 0.001). Eighty patients (78.4%) in the NOM-Group received follow-up imaging by ultrasound (US, n = 51) or computed tomography (CT, n = 29). In 57 cases, routine imaging examinations were conducted (43 US and 14 CT scans) without prior clinical deterioration. Fifty-fife (96.4%) of these imaging results revealed no new significant findings. Every failure of NOM was detected following clinical deterioration in the first 48 hours. Conclusion : To our knowledge this study includes the largest single centric patient cohort undergoing ultrasound as first-line follow-up imaging modality in the NOM setting of BSI in adult patients. The results indicate that a routine follow-up imaging, regardless of the modality, has limited therapeutic advantage. Indication for radiological follow-up should be based on clinical findings. If indicated, a CT scan should be used as preferred imaging modality.