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Retrospective review of injury severity, interventions and outcomes among helicopter and nonhelicopter transport patients at a Level 1 urban trauma centre.

BACKGROUND
Air ambulance transport for injured patients is vitally important given increasing patient volumes, the limited number of trauma centres and inadequate subspecialty coverage in nontrauma hospitals. Air ambulance services have been shown to improve patient outcomes compared with ground transport in select circumstances. Our primary goal was to compare injuries, interventions and outcomes in patients transported by helicopter versus nonhelicopter transport.


METHODS
We performed a retrospective 10-year review of 14 440 patients transported to an urban Level 1 trauma centre by helicopter or by other means. We compared injury severity, interventions and mortality between the groups.


RESULTS
Patients transported by helicopter had higher median injury severity scores (ISS), regardless of penetrating or blunt injury, and were more likely to have Glasgow Coma Scale scores less than 8, require airway control, receive blood transfusions and require admission to the intensive care unit or operating room than patients transported by other means. Helicopter transport was associated with reduced overall mortality (odds ratio 0.41, 95% confidence interval 0.33-0.39). Patients transported by other methods were more likely to die in the emergency department. The mean ISS, regardless of transport method, rose from 12.3 to 15.1 (p = 0.011) during our study period.


CONCLUSION
Patients transported by helicopter to an urban trauma centre were more severely injured, required more interventions and had improved survival than those arriving by other means of transport.