Predictors of splenic artery embolization as an adjunct to non-operative management of stable blunt splenic injury: a multi-institutional study

BACKGROUND: We sought to identify predictors of splenic artery embolization (SAE) over observation for hemodynamically stable patients with blunt splenic injury (BSI), by Organ Injury Scale (OIS) grade. METHODS: This was a multi-institutional retrospective study of all adults (≥18) with BSI who were initially managed non-operatively between 2014 and 2016. Multivariate logistic regression analysis was used to identify predictors of SAE by OIS grade. Covariates included radiographic characteristics (presence/quantity of hemoperitoneum, blush, vascular injury), demographics (age, sex, cause), Injury Severity Score, vital signs, and hemoglobin values. We also examined outcomes of death, length of stay (LOS), intensive care unit (ICU) admission, blood products, and failed non-operative management (NOM). RESULTS: Among 422 patients with stable BSI, 93 (22%) had SAE and 329 (78%) were observed. The rate of SAE increased by grade (p<0.001). In grade I and II BSI, 7% had SAE; significant predictors of SAE were blush (OR: 5.9, p=0.02), moderate or large hemoperitoneum (OR: 3.0, p=0.01), and male sex (OR: 6.3, p=0.05). In grade III BSI, 26% had SAE; significant predictors included moderate or large hemoperitoneum (OR: 3.9, p=0.04), motor vehicle crash (OR: 6.1, p=0.005), and age (OR=1.4, 40% with each decade increase in age, p=0.02). The rate of SAE was 52% for grade IV and 85% for grade V BSI; there were no independent predictors of SAE in either grade. Clinical outcomes were comparable by NOM strategy and grade, except longer LOS with SAE in grades I–III (p<0.05) and longer ICU LOS with SAE in grades I–IV (p<0.05). Only 5 (1.2%) patients failed NOM (4 observation, 1 SAE). CONCLUSION: These results strongly support SAE consideration for patients with stable grade IV and V BSI even if there are no other high-risk clinical or radiographic findings. For grades I–III, the identified predictors may help refine consideration for SAE. LEVEL OF EVIDENCE: Level III, retrospective epidemiological study.