Installation of Public Access Defibrillators for Out-of-Hospital Cardiac Arrests: Identifying Suitable Locations by Using a Geographic Information System

Abstract

Background: Survival following an out-of-hospital cardiac arrest depends on prompt defibrillation. Despite the efforts made to install automated external defibrillators (AEDs) in crowded areas, their usage rate remains suboptimal. This study evaluated the efficiency of installing AEDs at key landmarks in Taoyuan City to enhance accessibility and usage.

Methods and results: This retrospective cohort study analyzed nontraumatic public out-of-hospital cardiac arrest cases in Taoyuan City from 2017 to 2021, using data from the Taoyuan Fire Department and a regional registry. AED data were collected for 1163 devices. A geographic information system mapped target locations within the city, and real-world walking routes were examined to assess coverage. The primary outcome was actual coverage and the coverage efficiency ratio, calculated as the actual coverage divided by the number of facilities at a location. The coverage efficiency ratio compared the coverage efficiency of target locations with existing public access defibrillators (PADs). Top locations for superior coverage in both downtown and outside downtown areas were bus stops and convenience stores (7-Eleven and FamilyMart), which outperformed existing PADs. Convenience stores had a higher coverage efficiency ratio than the public service sector. Bus stops showed high AED usage rates before ambulance arrival.

Conclusions: The current PAD locations in Taoyuan City offer limited coverage, which highlights the need for strategically installed AEDs, particularly in convenience stores. Policymakers should consider using the cultural relevance and accessibility of convenience stores, particularly 7-Eleven branches, to enhance AED usage rates.

Keywords: automated external defibrillators; emergency medical services; geographic information system; out‐of‐hospital cardiac arrest; public access defibrillators.

Figure 1. Illustration of the calculation of parameters in this study.

Assuming there are 3 OHCA cases occurring in this hypothetical area (Cross sign), and their occurrence times are shown in brackets. Dashed arrow represents a walking route <100 meters from the OHCA case to closest existing PAD (circle sign) or closest one facility of target location (triangle sign). The blue triangle sign represents that the OHCA case is covered by the facility not only spatially but also temporally (actual coverage). The yellow triangle sign represents that the OHCA case is covered by the facility only spatially (total coverage). *CE, coverage efficiency = Actual coverage/Facilities number. It represents how many OHCA cases can be covered if all facilities of target location are equipped with PAD. #CE ratio = CE of target location/CE of existing PAD. It represents how many times more OHCA cases can be covered per PAD at target location compared with existing PAD. In this demonstration, placing PAD in all facilities of target location can provide 2 to 3 times fewer OHCA cases than existing PAD location. CE indicates coverage efficiency; OHCA, out‐of‐hospital cardiac arrest; and PAD, public access defibrillator.

Figure 2. Flowchart of the case selection process.

OHCA indicates out‐of‐hospital cardiac arrest.

Figure 3. Distribution of OHCA cases, existing AEDs, and convenience stores.

AED indicates automated external defibrillator; and OHCA, out‐of‐hospital cardiac arrest.