Modelling Optimal Location for Pre-Hospital Helicopter Emergency Medical Services

Background: Increasing the range and scope of early activation/auto launch helicopter emergencymedical services (HEMS) may alleviate unnecessary injury mortality that disproportionately affectsrural populations. To date, attempts to develop a quantitative framework for the optimal locationof HEMS facilities have been absent.Methods: Our analysis used five years of critical care data from tertiary health care facilities, spatialdata on origin of transport and accurate road travel time catchments for tertiary centres. Alocation optimization model was developed to identify where the expansion of HEMS would coverthe greatest population among those currently underserved. The protocol was developed usinggeographic information systems (GIS) to measure populations, distances and accessibility toservices.Results: Our model determined Royal Inland Hospital (RIH) was the optimal site for an expandedHEMS – based on denominator population, distance to services and historical usage patterns.Conclusion: GIS based protocols for location of emergency medical resources can providesupportive evidence for allocation decisions – especially when resources are limited. In this study,we were able to demonstrate conclusively that a logical choice exists for location of additionalHEMS. This protocol could be extended to location analysis for other emergency and healthservices.