Military helicopter experience led to widespread adoption in the US for civilian trauma beginning in the 1970s. This has had the significant side effect of extending the reach of trauma centers to a significant percentage of the US population. But because of safety considerations and concerns about appropriate use, the overall benefit continues to be questioned.
Most existing studies have been small, single institution projects. Researchers at the University of Rochester designed a very large study using the National Trauma Databank. They identified over 250,000 patients transported from the injury scene, 16% of whom were transported by ‘copter, the remainder by ground.
Patients transported by air were more severely injured and were more likely to have a severe head injury or abnormal vital signs. They also had longer hospital and ICU stays, and were more likely to require a ventilator or emergency surgery.
Despite the fact that response and scene times were longer for helicopter transports, air transport was a predictor of survival when injury severity was taken into consideration. This type of study can’t tell why survival is better, but possibilities include distance traveled and a higher level of care provided by air EMS personnel. Aeromedical EMS personnel are more likely to trained to perform advanced techniques such as intubation, crich, and transfusion, and generally have more experience with trauma patients.
Use of this scarce resource for trauma patient transport remains expensive, and as recent accident statistics imply, somewhat dangerous. Trauma centers and systems need to develop evidence-based guidelines that use helicopters intelligently for benefit of the patient, not the aeromedical service owners.
Reference: Helicopters and the civilian trauma system: national utilization patterns demonstrate improved outcomes after trauma injury. J Trauma 69(5):1030-6, 2010.