On observing public AEDs for a period of 5 years, we found that most AEDs had a relatively good maintenance status, with more than 97% of the AEDs operating normally. However, 15% of the AEDs were not ready for use, and invalid electrode was the most common cause for this. Further, 44% of the AEDs had limited 24-h use, and limited 24-h accessibility was the most common cause for this. Factors related to management and maintenance of AED and accessibility to AED were found to have improved over time. The proportion of valid electrodes decreased over time. Only around 1% of the AEDs were actually used. This rate did not change during the study period.
For successful implementation of PADs, four essential elements are required, namely planned and practiced response, training of anticipated rescuers in CPR and use of an AED, link to the local emergency medical system (EMS), and a process for continuous quality improvement.11 In the process of developing and implementing the PAD program, the government or community has paid attention mainly to the installation of AEDs and link to the EMS system through legislation or guidelines.12,13 In addition, the AED must be maintained in a state of being ready-to-use for 24 h a day. AEDs need to be maintained and tested regularly in accordance with the applicable rules and regulations established by governmental authorities. However, the maintenance and management of AEDs may be the responsibility of the locations holding the AEDs, considering that the community or government may not be able to directly manage the maintenance of the AEDs. Although each country or community has legal provisions for AED registration and management, many public AEDs are not registered in the national registry system or their management status is often unknown. In the Swedish experience, a large proportion (43%) of AEDs was not registered in their registry because of the unawareness of the AED registry or difficulty in registering although those AEDs had high functionality.14 In a report assessing Canadian public AED registries, governance and administrative processes across registries were found to be irregular. Some registries do not use a standardized validation or quality surveillance process, which might result in the loss of important information on AED usability, including battery and electrode validity.15
In the present study, a trained inspector checked the management and maintenance status of each AED with regard to manager, accessibility, and equipment and electrode status by annually visiting the installation site. To the best of our knowledge, this is the first report on the management and maintenance status of AEDs by on-site inspection. In this study, the maintenance of the defibrillator itself gradually improved during the observation period. However, a significant proportion (44%) of AEDs had limited 24-h availability and this proportion increased over time. In particular, 3 years after the inspection began, the percentage of electrodes that had passed their expiration date was found to have increased. The defibrillator itself does not need a separate function check as it reports data by performing self-tests on its internal circuitry to ensure readiness.16 Two important accessories, i.e., batteries and electrodes, are subjected to inspection during defibrillator maintenance checks along with the defibrillator equipment itself. Since the battery is installed in the defibrillator, the charging status can be checked using the indicator. It is checked along with the defibrillator operation status. On the other hand, since the electrode is separate from the defibrillator, the validity of the electrode must be checked separately by its expiration date. Therefore, to ensure the working status of the electrode, the manager needs to be aware of the periodic replacement plan. In addition, in cases where the AED is installed with non-governmental external financial support, there is often no financial plan for replacing defibrillator accessories. In such cases, even if the AED manager or inspector finds a problem with the electrodes, the problem cannot be solved. In this respect, when purchasing a defibrillator and installing it in a public space, it is necessary to establish a supply or financial plan for maintaining its accessories along with an inspection plan.
The use of AEDs in public places is related to the number of cardiac arrests in the installation area, the willingness of witnesses to use AEDs, and 24-h availability of the AEDs.17–19 AEDs are highly accessible during weekdays, but their accessibility declines in the evenings, including nighttime, and on weekends. This limitation in accessibility is associated with reduced use of AEDs.20 As observed in our study, the 24-h availability was limited for AEDs installed in places that were not open for 24 h, such as multi-use facilities, schools, public buildings, and welfare facilities. In addition, we found that the proportion of limited 24-h availability was the highest in residential settings. The limited use of AEDs in a residential setting can be a major hindrance to the PAD program. Only approximately 1% of the AEDs were actually used. This low utilization rate might be associated with the low 24-h availability. Thus, when planning AED installation, it is necessary to consider whether the installation site is open for 24 h.