Introduction:
Following the implementation of the Danish AED network and a nationwide citizen responder (CR) program for out-of-hospital cardiac arrest (OHCA), CR and AED coverage for OHCAs according to area types has not been investigated. We aimed to assess AED and CR coverage of historical OHCAs according to area types in daytime (12pm) and nighttime (12am).
Methods:
We included non-EMS witnessed OHCAs from the Danish Cardiac Arrest Registry (2016-2019) and AEDs registered with the Danish AED network (November 2020) available at 12am (n=22,418) and 12pm (n=14,734). Exact locations of CRs who were registered with the national CR program by December 2020 were identified on a normal working day (Wednesday, December 2, 2020) at 12am and 12pm (representing day- and nighttime location). OHCAs, AEDs, and CRs were identified and geocoded using a geographical information system. Urban Atlas was used to categorize areas into subgroups using satellite images; high density residential areas, low density residential areas, public and industrial sites, nature, sport and leisure facilities, transportation (e.g. airport and railway stations), and fast transit roads.
Results:
A total of 10,126 OHCAs (63.0% male, median age 73 years). We mapped 14,119 AEDs (12 pm) and 24,372 CR (12 pm) in Urban Atlas. Most OHCAs in all area types were covered by >= 1 AED. A greater variation was observed in CR coverage when compared to AED coverage, according to area type. Little difference in coverage of both AED and CR according to time of day was observed. (Figure 1)
Conclusion:
The highest CR and AED coverage were observed in high density residential areas, transportation sites, public and industrial areas, and sport and leisure facilities, which is where most OHCAs occurred. These findings indicate a high coverage of citizen responders and AEDs in Denmark.