Crossing the line: access to trauma care across state borders.

Objective: This study investigates the challenge posed by state borders by identifying the population, injury, and geographic scope of areas of the country where the closest trauma center is out-of-state, and by collating state emergency medical services (EMS) policies relevant to cross-border trauma transport. Methods: We identified designated levels I, II, and III trauma centers using data from American Trauma Society. ArcGIS was used to map the distance between US census block groups and trauma centers to identify the geographic areas for which cross-border transport may be most expedient. National Highway Traffic Safety Administration data were queried to quantify the proportion of fatal crashes occurring in the areas of interest. State EMS protocols were categorized by stance on cross-border transport. Results: Of 237 596 included US census block groups, 18 499 (7.8%) were closest to an out-of-state designated level I or II trauma center. These census block groups accounted for 6.9% of the US population and 9.5% of all motor vehicle fatalities. With the inclusion of level III trauma centers, the number of US census block groups closest to an out-of-state designated level I, II, or III trauma center decreased to 13 690 (5.8%). These census block groups accounted for 5.1% of the US population and 7.1% of all motor vehicle fatalities. Of the 48 contiguous states, 30 encourage cross-border transport, 2 discourage it, 12 are neutral, and 4 leave it to local discretion. Conclusion: Cross-border transport can expedite access to care in at least 5% of US census block groups. While few states discourage this practice, more robust policy guidance could reduce delays and enhance care. Level of Evidence: III, Epidemiological.