Epidemiology of traumatic deaths: comprehensive population-based assessment.

Background: The epidemiology of traumatic deaths was periodically described during the development of the American trauma system between 1977 and 1995. Recognizing the impact of aging populations and the potential changes in injury mechanisms, the purpose of this work was to provide a comprehensive, prospective, population-based study of Australian trauma-related deaths and compare the results with those of landmark studies.

Methods: All prehospitalization and in-hospital trauma deaths occurring in an inclusive trauma system at a single Level 1 trauma center [400 patients with an injury severity score (ISS) >15/year] underwent autopsy and were prospectively evaluated during 2005. High-energy (HE) and low-energy (LE) deaths were categorized based on the mechanism of the injury, time frame (prehospitalization, <48 hours, 2-7 days, >7 days), and cause [which was determined by an expert panel and included central nervous system-related (CNS), exsanguination, CNS + exsanguination, airway, multiple organ failure (MOF)]. Data are presented as a percent or the mean +/- SEM.

Results: There were 175 deaths during the 12-month period. For the 103 HE fatalities (age 43 +/- 2 years, ISS 49 +/- 2, male 63%), the predominant mechanisms were motor vehicle related (72%), falls (4%), gunshots (8%), stabs (6%), and burns (5%). In all, 66% of the patients died during the prehospital phase, 27% died after <48 hours in hospital, 5% died after 3 to 7 days in hospital, and 2% died after >7 days. CNS (33%) and exsanguination (33%) were the most common causes of deaths, followed by CNS + exsanguination (17%) and airway compromise 8%; MOF occurred in only 3%. Six percent of the deaths were undetermined. All LE deaths (n = 72, age 83 +/- 1 years, ISS 14 +/- 1, male 45%) were due to low falls. All LE patients died in hospital (20% <48 hours, 32% after 3-7 days, 48% after 7 days). The causes of deaths were head injury (26%) and complications of skeletal injuries (74%).

Conclusions: The HE injury mechanisms, time frames, and causes in our study are different from those in the earlier, seminal reports. The classic trimodal death distribution is much more skewed to early death. Exsanguination became as frequent as lethal head injuries, but the incidence of fatal MOF is lower than reported earlier. LE trauma is responsible for 41% of the postinjury mortality, with distinct epidemiology. The LE group deserves more attention and further investigation.