Variation in Outcomes Associated With Blunt Splenic Injury Management

Introduction The management of blunt splenic injury has evolved to include splenic artery embolization in addition to non-surgical management, and splenic surgery. Though research has been conducted examining outcomes between management approaches, the inferential findings are often limited by single-site study designs and small sample sizes. However, results from large-scale prior studies can inform inference if a non-frequentist (Bayesian) framework is used. Therefore, the purpose of this study was to examine mortality and length of stay associated with blunt splenic injury management using both frequentist and Bayesian methods. Methods A total of 56 patients presenting with blunt splenic injury were included in this retrospective, single-center, quantitative study from January 1, 2021 to December 31, 2022 to inform both methodological approaches. Findings from a national retrospective sample of 117,743 patients presenting with blunt splenic injury between 2007 and 2015 were included in the prior distribution for the Bayesian estimates to provide sufficient statistical power and improve internal validity and generalizability of findings. Results Mortality rates and hospital mean length of stay were not significantly different between blunt splenic injury management approaches of non-operative management (n=43), surgery (n=7), and splenic artery embolization (n=6) using a frequentist approach (9.3%, 0%, and 0%, P=.52; and 10.8 (15.8), 10.8 (4.7), and 4.6 (1.8), P=.86, respectively). Bayesian 95% highest density interval (HDI) estimates of the likelihood of mortality ([0.02; 0.18], [-6.4^e-23; 0.3], and [-2.2^e-22; 0.3]) and hospital mean length of stay ([7.7; 8.3], [11.0; 12.3], and [8.7; 10.2]) provided reduced uncertainty in point and dispersion estimates. Conclusions The inclusion of findings from large high-quality studies provides increased certainty in estimates from smaller studies. Posterior estimates can inform predictive models for testing in future studies.