2026/07/15 by Adam J. Boulton, Nigel Lang, Joshua Miller +9 · 1 voice
Medicine · #Cardiac Arrest and Resuscitation #Trauma and Emergency Care Studies #Emergency and Acute Care Studies
paper · doi:10.1186/s13049-026-01655-9
openalex publication_date 2026/07/15 · openalex created_date 2026/07/16 · openalex updated_date 2026/07/23
BACKGROUND: Prehospital critical care is associated with improved outcomes following out-of-hospital cardiac arrest (OHCA), but may not be distributed equitably. AIM: To examine the alignment between prehospital critical care provision and neighbourhood OHCA risk, predicted survival, and deprivation across three neighbouring ambulance regions in England. METHODS: Data on all OHCAs treated by three neighbouring English ambulance services (2018-2023) were aggregated to the neighbourhood level. Prehospital critical care response time predictions were generated from service-supplied operational parameters and calibrated against observed data with rural-urban adjustment. High-risk neighbourhoods were defined by above-median OHCA incidence and below-median bystander CPR. Pre-EMS predicted survival was estimated using a published model. Deprivation was measured with Index of Multiple Deprivation. Weighted regression models with service-by-response time interaction terms examined each neighbourhood metric per 5-minute response time increase. A secondary analysis examined a HEMS-only configuration by removing the unique urban, NHS car asset in service B. RESULTS: Overall, 52.9% of the resident population and 51.3% of OHCAs were within 15 min of a prehospital critical care response. In two services, increasing response time was associated with higher odds of a neighbourhood being high-risk and with greater deprivation. For pre-EMS predicted survival, poor alignment was found in one service, favourable alignment in another, and no significant association in the third. Service B showed favourable alignment across all three metrics. Removing the urban car asset (HEMS-only configuration) reversed this favourable pattern, producing gradients consistent with the other two services. Sensitivity analysis using observed response times and distances produced consistent but attenuated associations. CONCLUSION: Prehospital critical care provision, particularly HEMS, is generally poorly aligned with neighbourhood OHCA risk, pre-EMS predicted survival, and deprivation. The only region demonstrating favourable cardiac arrest alignment was attributable to its urban NHS car asset. Expanding car-based prehospital critical care in deprived urban areas may warrant consideration as a strategy to reach more OHCA patients and improve equity of access.