Major trauma during COVID-19 in a level 1 trauma centre in Switzerland - a cohort study comparing the years 2020 and 2019

INTRODUCTION: The COVID-19 pandemic and the associated restrictions may have modified the activities of the Swiss population and thus altered trauma patterns. MATERIALS AND PATIENTS: All adult patients with major trauma admitted to our institution in 2019 and 2020 were assessed using the Injury Severity Score (ISS), by body region involved, type of injury, age, admission to an intensive care unit and 30-day mortality. RESULTS: In 2020, 454 patients with major trauma were admitted to our institution, 17% fewer than in the previous year. The drop in the number of major trauma patients proceeded with and overlapped both the first and second peaks in incidence of the pandemic and the associated restrictions. The median ISS was higher in 2020 (25, in-terquartile range [IQR] 17-26.5) than in 2019 (22, IQR 16-26, p = 0.04). There were no significant differences in body region involved, type of injury or age (p >0.05).In 2020, a higher percentage of patients were admitted to an intensive care unit (86.5% vs 77.7%, p <0.001) and died within 30 days (8.8% vs 5.0%, p = 0.015). The 30-day mortality was higher in 2020 than in 2019, with an odds ratio of 1.80 (95% confidence interval 1.04-3.10, p= 0.036) after adjustment for the following potential confounders ISS, age, gender and type of injury. CONCLUSION: In the first year of the COVID-19 pandemic,fewer patients with major trauma were admitted to our institution. However, the patients admitted were more severely injured and more often died within 30 days. Understanding the differences in injury patterns and admissions in major trauma patients under special conditions - such as a pandemic - could help to allocate rare resources adequately.