Patient and trauma center characteristics associated with helicopter emergency medical services transport for patients with minor injuries in the United States.

Background Helicopter emergency medical services (EMS) transport is expensive, and previous work has shown that cost-effective use of this resource is dependent on the proportion of minor injuries flown. To understand how overtriage to helicopter EMS versus ground EMS can be reduced, it is important to understand factors associated with helicopter transport of patients with minor injuries. Objectives The aim was to characterize patient and hospital characteristics associated with helicopter transport of patients with minor injuries. Methods This was a retrospective analysis of adults ≥18 years who were transported by helicopter to Level I/II trauma centers from 2009 through 2010 as identified in the National Trauma Data Bank. Minor injuries were defined as all injuries scored at an Abbreviated Injury Scale (AIS) score of <3. Patient and hospital characteristics associated of being flown with only minor injuries were compared in an unadjusted and adjusted fashion. Hierarchical, multivariate logistic regression was used to adjust for patient demographics, mechanism of injury, presenting physiology, injury severity, urban–rural location of injury, total EMS time, hospital characteristics, and region. Results A total of 24,812 records were identified, corresponding to 76,090 helicopter transports. The proportion of helicopter transports with only minor injuries was 36% (95% confidence interval [CI] = 34% to 39%). Patient characteristics associated with being flown with minor injuries included being uninsured (odds ratio [OR] = 1.36, 95% CI = 1.26 to 1.47), injury by a fall (OR = 1.32, 95% CI = 1.20 to 1.45), or other penetrating trauma (OR = 2.52, 95% CI = 2.12 to 3.00). Being flown with minor injuries was more likely if the patient was transported to a trauma center that also received a high proportion of patients with minor injuries by ground EMS (OR = 1.89, 95% CI = 1.58 to 2.26) or a high proportion of EMS traffic by helicopter (OR = 1.35, 95% CI = 1.02 to 1.78). No significant association with urban–rural scene location or EMS transport time was found. Conclusions Better recognizing which patients with falls and penetrating trauma have serious injuries that could benefit from being flown may lead to the more cost-effective use of helicopter EMS. More research is needed to determine why patients without insurance, who are most at risk for high out-of-pocket expenses from helicopter EMS, are at higher risk for being flown when only having minor injuries. This suggests that interventions to optimize cost-effectiveness of helicopter transport will likely require an evaluation of helicopter triage guidelines in the context of regional and patient needs. Resumen Introduccion El transporte de los Servicios de Emergencias Medicas (SEM) en helicoptero es caro y un trabajo previo ha mostrado que la costo-efectividad del uso de este recurso es dependiente de la proporcion de lesiones menores transportadas por via aerea. Para entender como el sobretriaje del SEM en helicoptero puede ser reducido, es importante entender los factores asociados con el transporte en helicoptero de los pacientes con lesiones menores. Objetivos El objetivo fue conocer las caracteristicas del paciente y del hospital asociadas con el transporte en helicoptero de los pacientes con lesiones menores. Metodologia Este fue un analisis retrospectivo de los adultos de 18 anos o mas que fueron transportados en helicoptero a centros de traumatologia de Nivel I/II del National Trauma Data Bank desde 2009 a 2010. Se definieron lesiones menores como toda lesion puntuada como menor de 3 segun la Abbreviated Injury Scale [AIS]. Se compararon las caracteristicas del paciente y del hospital asociadas al transporte por via aerea con solo lesiones menores, de forma no ajustada y ajustada. Se utilizo una regresion logistica para ajustar por la demografia del paciente, el mecanismo de la lesion, la situacion fisiologica de presentacion, la gravedad de la lesion, la localizacion urbana-rural, el tiempo del SEM total y las caracteristicas del hospital y la region. Resultados Se identificaron 24.812 historias clinicas, correspondientes a 76.090 transportes en helicoptero. El porcentaje de transportes en helicoptero con solo lesiones menores fue de un 36% (intervalo de confianza [IC] al 95% = 34% a 39%). Las caracteristicas del paciente asociadas con el transporte aereo con lesiones menores incluyeron: no estar asegurado (odds ratio [OR] 1,36, IC 95% = 1,26 a 1,47) y lesiones por una caida (OR 1,32, IC 95% = 1,20 a 1,45) u otro traumatismo penetrante (OR 2,52, IC 95% = 2,12 a 3,00). El transporte aereo con lesiones menores fue mas probable si el paciente se transporto a un centro traumatologico que tambien recibio un alto porcentaje de pacientes con lesiones menores del SEM por tierra (OR 1,89, IC 95% = 1,58 a 2,26) o una alto porcentaje de trafico del SEM por helicoptero (OR 1,35, IC 95% = 1,02 a 1,78). No se encontro un asociacion significativa con la localizacion del escenario urbano-rural ni con el tiempo total del SEM. Conclusiones El mejor reconocimiento de que pacientes con caidas o traumatismos penetrantes tienen lesiones graves que podrian beneficiarse del transporte aereo puede conducir a un uso mas costo-efectivo del SEM por helicoptero. Se necesita mas investigacion para determinar por que los pacientes sin seguro, quienes estan en mayor riesgo de gastos extra del SEM por helicoptero, tienen mayor probabilidad de transporte aereo cuando solo tienen lesiones menores. Esto indica que las intervenciones para optimizar la costo-efectividad del transporte en helicoptero probablemente requieran una evaluacion de las guias de triaje para helicoptero en el contexto de las necesidades regionales y del paciente.