Background: Air ambulance services are commonly used to expedite interfacility transport of injured patients to trauma centers. There is a lack of evidence surrounding risk factors for delays in interfacility transport of these patients. The purpose of this study was to examine patient, paramedic, and institutional-related characteristics for delay and identify specific causes of delays in interfacility transfers by air ambulance. Methods: This was a retrospective cohort study of injured patients undergoing interfacility transfer to a trauma center who were transported by air ambulance. Quantile regression was used to evaluate the impact of patient, paramedic and institutional characteristics on various time intervals of the interfacility transport process. Results: There are three key findings in our study. First, the use of rotor-wing aircraft and hospital-based helipads had substantially lower transport times. Second, transports from academic centers take longer compared to sending facilities with fewer resources. Third, interfacility transport times are heavily skewed and delays disproportionately affect longer patient transports. Conclusions: Ventilator dependence, paramedic level of care, classification of sending facility and helipad availability are associated with delays to interfacility transport of injured patients. Efforts can be made at both the air ambulance and institutional levels to ensure timely and efficient transports.
Keywords: air ambulance; interfacility transfer; prehospital care; trauma.