Background: The distance beyond which helicopter transport is faster than ground for interfacility transfer of trauma patients has not been established. Our objective was to determine whether such a threshold exists.
Methods: A retrospective cohort study was conducted involving 243 patients transported by land and 139 patients by air from 13 sites during a 3-year period. Time intervals between critical events were compared for the two modes of transport at each site.
Results: The time interval between the decision to transfer and the actual departure time was shorter for patients transferred by land from all sites studied (mean 41.3 versus 89.7 minutes, p < 0.001). The travel time was shorter by helicopter from all sites (mean 58.4 versus 78.9 minutes, p < 0.001). The time between the decision to transfer and the arrival at the trauma center was similar at most sites but faster by land overall (mean 120.3 versus 150.0 minutes, p = 0.014). No threshold was detected beyond which helicopter transport was superior.
Conclusions: Several factors other than the distance to be traveled determine the time required for interfacility transfer of trauma patients. A fixed distance threshold beyond which helicopter transport should be used does not exist. The decision as to which mode of transport to use for emergent trauma patient transfers should be based upon multiple factors including the distance traveled and ambulance availability, and must be individualized for each site that transfers patients.