Major trauma patients and their outcomes - A retrospective observational study of critical care trauma admissions to a trauma unit with special services.

Introduction: International data describes a changing pattern to trauma over the last decade, with an increasingly comorbid population presenting challenges to trauma management and resources. In Ireland, resource provision and management of trauma is being transformed to deliver a trauma network, in line with international best practice. Our hospital plays a crucial role within this network and is designated a Trauma Unit with Specialist Services (TUSS) to distinguish it from standard trauma units.

Methods: This study aims to describe the characteristics of patients and injuries and assess trends in mortality rates. It is a retrospective observational study of adult ICU trauma admissions from August 2010 to July 2021. Primary outcome was all-cause mortality at 30-days, 90-days, and 1 year. Secondary outcomes included length of stay, disposition, and complications. Patients were categorised by age, injury severity score (ISS), and mechanism of injury.

Results: In all, 709 patients were identified for final analysis. Annual admissions doubled since 2010/11, with a trough of 41 admissions, increasing to peak at 95 admissions in 2017/18. Blunt trauma accounted for 97.6% of cases. Falls <2 m (45.4%) and RTAs (29.2%) were the main mechanisms of injury. Polytrauma comprised 41.9% of admissions. Traumatic brain injury accounted for 30.2% of cases; 18.8% of these patients were transferred to a neurosurgical centre. The majority of patients, 58.1%, were severely injured (ISS ≥ 16). Patients ≥ 65 years of age accounted for 45.7% of admissions, with falls <2 m their primary mechanism of injury. The primary outcome of all-cause mortality reduced with an absolute risk reduction (ARR) of 8.0% (95% CI: -8.37%, 24.36%), 12.9% (95% CI: -4.19%, 29.94%) and 8.2% (95% CI: -9.64%, 26.09%) for 30-day, 90-day and 1-year respectively. Regression analysis demonstrated a significant reduction in mortality for 30-days and 90-days post presentation to hospital (P-values of 0.018, 0.033 and 0.152 for 30-day, 90-day and 1-year respectively).

Conclusion: The burden of major trauma in our hospital is considerable and increasing over time. Substantial changes in demographics, injury mechanism and mortality were seen, with outcomes improving over time. This is consistent with international data where trauma systems have been adopted.