Accelerating AED Use In Out-of-Hospital Cardiac Arrest With Combinations Of First Responder And Drone Delivery To Achieve 5-minute AED Deployment

Background: Defibrillation in the critical first minutes of out-of-hospital cardiac arrests (OHCAs) can significantly improve survival rates but getting timely access to AEDs is a major barrier. We estimated the potential of a statewide program for drone-delivered AEDs in North Carolina (NC) when integrated into EMS response that includes police and fire first responders (FR). Methods: Using CARES registry data, we included all patients >18 years with OHCA occurring between 1/1/2013-12/31/2019 in 44 NC counties. We determined the improvement in AED arrival time by providing AEDs to all FR, who routinely arrive earlier than EMS but currently may not have an AED. We developed mathematical models to place drones within each county to achieve 5-min AED arrival times for 75% of OHCAs in each county. We predicted ambulance response times and resulting drone dispatch decisions using linear regression. Models were trained using 2013-2018 OHCA data and were validated with 2019 data. Mean response times were compared with historical response using the Wilcoxon signed-rank test. Results: We identified 27,199 OHCAs with historical median county-level response times of 6.7 [IQR: 5.9-7.5 mins]. Providing all FR with AEDs reduced response times to 5.9 [IQR: 5.3-6.9] mins and increased OHCAs with AED arrival times of <5 min to 35.6% [IQR: 26.1-43.4%]. Mathematical models estimated that 273 optimally located drones across the 44 counties would reduce response times for out-of-sample OHCAs to 3.7 [IQR: 3.4-3.9] mins and increase OHCAs with AED arrival times of <5 min to 73.0% [IQR: 65.4-78.8%]. The drone network improved response times (p<0.05) compared to historical response times in 43 out of 44 counties. Conclusion: Full deployment of AEDs by FR plus optimized drone AED delivery was estimated to significantly improve response times based on historical patterns of OHCA in NC. The number of drones and their impact varies across counties based on OHCA incidence rates and population density.