Do direct admissions to trauma centers have a survival benefit compared to inter-hospital transfers in severe trauma?

Purpose: To compare mortality among severe and critically injured patients who were directly admitted (DA) to level I trauma center (TCI) or level II trauma center (TCII) with those who were transferred to a TCI after being initially admitted to a TCII. Methods: A cohort study of severe and critically injured patients (Injury Severity Score 16–75) hospitalized between 2010 and 2019 using data from the National Program for Trauma Registration. Multivariate logistic regression models estimated mortality risk, including stratified analyses. Results: Of the 27,131 hospitalizations, 9.5% were transfers, 60.1% were DA to TCI and 30.4% were DA to TCII. Children ages ≤ 17 years, Non-Jews (minority), critical injuries (ISS 25–75), head injuries (AIS ≥ 3) and fall injuries were significantly more frequent among transfers, compared with the DA groups. Evacuation by emergency medical services was less frequent among transfers. After accounting for possible confounders, transfers had a greater risk of in-hospital mortality [DA to TCI vs transfer, OR (95% CI) 0.61 (0.52–0.72); DA to TCII vs transfer, OR (95% CI) 0.78 (0.65–0.94)]. In stratified analyses, these mortality differences persisted among the sub-group of patients who sustained critical injuries, among the patients with non-penetrating injuries, among the elderly ages ≥ 65 year and during the first 2 weeks of hospitalization. Conclusion: This study has intervention implications that should be directed primarily at prehospital triage and the inter-hospital transfer processes. In addition, there may be a need to optimize the capabilities of regional trauma systems along with continuous performance evaluations and actions as required.