Car crashes are a significant cause of trauma death worldwide. Aortic injury is the cause of death in somewhere between 16% and 35% of these crashes (in the US). Over the years, automobile safety through engineering improvements has been rising. A recent poster presented at EAST 2012 looked at the effect of these improvements on mortality from aortic injury.
The authors analyzed the National Automotive Sampling System – Crashworthiness Data System database (NASS-CDS) for car model years dating from 1994 to 2010. They included any front seat occupants age 16 or more. Over 70,000 cases were reviewed.
- Overall mortality from aortic injury was 89%
- 75% of deaths occurred prior to arrival at a hospital
- Risk for suffering an aortic injury was statistically associated with age >=60, being male, being the front seat passenger, position further back from the steering wheel, and ejection from the vehicle
- The injury was more likely to occur when speed was >= 60mph, impact occurred with a fixed object, and in SUV vs pickup truck crashes
- Newer cars protected occupants from aortic injury in side-impact crashes, but the incidence actually increased in frontal-impact crashes
Bottom line: Aortic injury will remain a problem as long as we find ways to move faster than we can walk. Engineers will continue to make cars safer, but the increase in aortic injury in frontal impact in late model cars is puzzling. This phenomenon needs further analysis so that safety can be improved further. Trauma professionals need to keep this injury in mind in any high energy mechanism and order a screening chest CT appropriately.
Reference: Aortic injuries in new vehicles. Ryb et al, University of Maryland and Johns Hopkins. Poster presented at EAST Annual Meeting, January 2012.