Background: Road traffic accidents are the eighth leading cause of mortality globally and the second in Saudi Arabia. Trauma patients need specialized care and access to health care facilities. Early intervention by a multidisciplinary team results in better outcomes in terms of mortality and morbidity. The aim of this study was to analyze the association between the different mechanisms of injury that resulted in trauma team activations (TTAs) and the time in the 24-hour day over a 3-year period in a tertiary trauma center. Methods: A single center retrospective study with trauma patients triggering the TTA was conducted. The study was conducted over a 3-year period, and the sample size was 587. Results: The highest volume of TTA’s during the 3 years occurred from 20:00 and 23:00 and the busiest single hour was 21:00. Pedestrian trauma was more prevalent at the end of the day from 18:00 to 22:00. Our study showed the mechanism of injury for more than half of the sample was a motor vehicle accident, followed by pedestrian trauma. The highest proportion of the sample was admitted from the Emergency Department to an intensive care unit (46.6%) or operation room/angiography (37.5%). After 19:00, there were more severe injuries and unstable patients, who required an intensive care unit or operation room/angiography. The peak occurred after 17:00 for 1 hour. Age, systolic and diastolic blood pressure were not statically significant. The mortality rate was higher in TTA patients’ groups with an initial mean heart rate of 118 per minute and a 91% oxygen pulse oximetry. Conclusion: The outcome of trauma patients was affected by the time of the 24-hour day. Severe injuries and unstable patients were more prevalent during nighttime. A higher initial heart rate for TTA patients was linked with increased mortality.

Keywords: Trauma, Emergency Medicine, Trauma activation, health administration, Saudi Arabia