Saving lives with public access defibrillation: A deadly game of hide and seek

Optimisation of the deployment of automated external defibrillators in public places in England

Background

Ambulance services treat over 32,000 patients sustaining an out-of-hospital cardiac arrest annually, receiving over 90,000 calls. The definitive treatment for out-of-hospital cardiac arrest is defibrillation. Prompt treatment with an automated external defibrillator can improve survival significantly. However, their location in the community limits opportunity for their use. There is a requirement to identify the optimal location for an automated external defibrillator to improve out-of-hospital cardiac arrest coverage, to improve the chances of survival.

Methods

This was a secondary analysis of data collected by the Out-of-Hospital Cardiac Arrest Outcomes registry on historical out-of-hospital cardiac arrests, data held on the location of automated external defibrillators registered with ambulance services, and locations of points of interest. Walking distance was calculated between out-of-hospital cardiac arrests, registered automated external defibrillators and points of interest designated as potential sites for an automated external defibrillator. An out-of-hospital cardiac arrest was deemed to be covered if it occurred within 500 m of a registered automated external defibrillator or points of interest. For the optimisation analysis, mathematical models focused on the maximal covering location problem were adapted. A de novo decision-analytic model was developed for the cost-effectiveness analysis and used as a vehicle for assessing the costs and benefits (in terms of quality-adjusted life-years) of deployment strategies. A meeting of stakeholders was held to discuss and review the results of the study.

Results

Historical out-of-hospital cardiac arrests occurred in more deprived areas and automated external defibrillators were placed in more affluent areas. The median out-of-hospital cardiac arrest - automated external defibrillator distance was 638 m and 38.9% of out-of-hospital cardiac arrests occurred within 500 m of an automated external defibrillator. If an automated external defibrillator was placed in all points of interests, the proportion of out-of-hospital cardiac arrests covered varied greatly. The greatest coverage was achieved with cash machines. Coverage loss, assuming an automated external defibrillator was not available outside working hours, varied between points of interest and was greatest for schools. Dividing the country up into 1 km2 grids and placing an automated external defibrillator in the centre increased coverage significantly to 78.8%. The optimisation model showed that if automated external defibrillators were placed in each points-of-interest location out-of-hospital cardiac arrest coverage levels would improve above the current situation significantly, but it would not reach that of optimisation-based placement (based on grids). The coverage efficiency provided by the optimised grid points was unmatched by any points of interest in any region. An economic evaluation determined that all alternative placements were associated with higher quality-adjusted life-years and costs compared to current placement, resulting in incremental cost-effectiveness ratios over £30,000 per additional quality-adjusted life-year. The most appealing strategy was automated external defibrillator placement in halls and community centres, resulting in an additional 0.007 quality-adjusted life-year (non-parametric 95% confidence interval 0.004 to 0.011), an additional expected cost of £223 (non-parametric 95% confidence interval £148 to £330) and an incremental cost-effectiveness ratio of £32,418 per quality-adjusted life-year. The stakeholder meeting agreed that the current distribution of registered publicly accessible automated external defibrillators was suboptimal, and that there was a disparity in their location in respect of deprivation and other health inequalities.

Conclusions

We have developed a data-driven framework to support decisions about public-access automated external defibrillator locations, using optimisation and statistical models. Optimising automated external defibrillator locations can result in substantial improvement in coverage. Comparison between placement based on points of interest and current placement showed that the former improves coverage but is associated with higher costs and incremental cost-effectiveness ratio values over £30,000 per additional quality-adjusted life-year.

Study registration

This study is registered as researchregistry5121.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: NIHR127368) and is published in full in Health and Social Care Delivery Research; Vol. 13, No. 5. See the NIHR Funding and Awards website for further award information.

Strategic placement of volunteer responder system defibrillators

Volunteer responder systems (VRS) alert and guide nearby lay rescuers towards the location of an emergency. An application of such a system is to out-of-hospital cardiac arrests, where early cardiopulmonary resuscitation (CPR) and defibrillation with an automated external defibrillator (AED) are crucial for improving survival rates. However, many AEDs remain underutilized due to poor location choices, while other areas lack adequate AED coverage. In this paper, we present a comprehensive data-driven algorithmic approach to optimize deployment of (additional) public-access AEDs to be used in a VRS. Alongside a binary integer programming (BIP) formulation, we consider two heuristic methods, namely Greedy and Greedy Randomized Adaptive Search Procedure (GRASP), to solve the gradual Maximal Covering Location (MCLP) problem with partial coverage for AED deployment. We develop realistic gradually decreasing coverage functions for volunteers going on foot, by bike, or by car. A spatial probability distribution of cardiac arrest is estimated using kernel density estimation to be used as input for the models and to evaluate the solutions. We apply our approach to 29 real-world instances (municipalities) in the Netherlands. We show that GRASP can obtain near-optimal solutions for large problem instances in significantly less time than the exact method. The results indicate that relocating existing AEDs improves the weighted average coverage from 36% to 49% across all municipalities, with relative improvements ranging from 1% to 175%. For most municipalities, strategically placing 5 to 10 additional AEDs can already provide substantial improvements.

An innovative Hearing AED alarm system shortens delivery time of automated external defibrillator - A randomized controlled simulation study

Background

Early defibrillation with an automated external defibrillator (AED) is a key element in the out-of-hospital cardiac arrest (OHCA) chain. However, a public automatic defibrillator (PAD) is often not easily accessible during emergency situations. Here, we have developed an AED-based alarm system together with a smartphone Hearing AED application (APP) that would activate registered public access AED within 300 m radius from the location of an OHCA event. It also alerts nearby related personnel to bring in the AED to the OHCA location for emergency assistance. The aim of this study is to determine if this novel Hearing AED alarm system shortens the AED delivery time.

Methods

This was a randomized controlled simulation study. Participants were randomly assigned to one of the 3 groups: (a) bystander group, (b) APP responder group, and (c) AED alarm responder in equal ratios. The bystanders were stationed at the OHCA scene, and must access a nearby AED by the instruction of the dispatcher of emergency medical services. APP responders were stationed within 300 m of the cardiac arrest scene, and were activated by the Hearing AED APP. The AED alarm responders were brought to AED location, and were activated by the AED-based alarm device mounted on an AED case. We measured the time taken to find and bring the nearby AED to the OHCA scene. The primary outcome was the total delivery time in each group. The secondary outcomes were times needed: (a) from the starting point to AED place, (b) from AED place to the OHCA scene, and (c) the operation time.

Results

We enrolled 90 participants in this study. The total AED delivery times were significantly different across the 3 groups. The shortest time was in the AED alarm responder group, compared with the other two groups. The median time from the starting point to AED was statistically shorter in the bystander group than in the APP responder group (116.0 sec, IQR 80.0-135.0 vs 159.0 sec, IQR 98.5-200.5, p = 0.029). In the analysis with the general linear model, we found statistically shorter total AED delivery time in the AED alarm responder group (β = -122.4, p = 0.004). In contrast, the APP responder group was associated with a markedly longer total AED delivery time (β = 104.6, P=0.016).

Conclusion

In this simulation study, the Hearing AED system contributed to shortening the AED delivery time. Further studies are needed to determine its validation in the real world situation in the future.

Development of a centralised national AED (automated external defibrillator) network across all ambulance services in the United Kingdom

Background

Early cardiopulmonary resuscitation and defibrillation is key to increasing survival following an out-of-hospital-cardiac-arrest (OHCA). However, automated external defibrillators (AEDs) are used in a very small percentage of cases. Despite large numbers of AEDs in the community, the absence of a unified system for registering their locations across the UK's ambulance services may have resulted in missed opportunities to save lives. Therefore, representatives from the resuscitation community worked alongside ambulance services to develop a single repository for data on the location of AEDs in the UK.

Methods

A national defibrillator network, "The Circuit", was developed by the British Heart Foundation in collaboration with the Association of Ambulance Chief Executives, the UK ambulance services, the Resuscitation Council UK and St John Ambulance. The database allows individuals or organisations to record information about AED location, accessibility, and availability. The database synchronises with ambulance computer aided dispatch systems to provide UK ambulance services with real-time information on the nearest, available AED.

Results

The Circuit was successfully rolled out to all 14 UK ambulance services. Since 2019, 82,108 AEDs have been registered. Of the AED data collected by The Circuit, 54% were not previously registered to any ambulance service, and are therefore new registrations.

Conclusion

The Circuit provides ambulance services with a single point of access to AED locations in the UK. Since the launch of the system the number of defibrillators registered has doubled. Linking the Circuit data with patient outcome data will help understand whether improving the accessibility to AEDs is associated with increased survival.

Knowledge and barriers of out of hospital cardiac arrest bystander intervention and public access automated external defibrillator use in the Northeast of England: a cross-sectional survey study

Intervention by members of the public during an out of hospital cardiac arrest (OHAC) including resuscitation attempts and accessible automated external defibrillator (AED) has been shown to improve survival. This study aimed to investigate the OHCA and AED knowledge and confidence, and barriers to intervention, of the public of North East England, UK. This study used a face-to-face cross-sectional survey on a public high street in Newcastle, UK. Participants were asked unprompted to explain what they would do when faced with an OHCA collapse. Chi-Square analysis was used to test the association of the independent variables sex and first aid trained on the participants' responses. Of the 421 participants recruited to our study, 82.9% (n = 349) reported that they would know what to do during an OHCA collapse. The most frequent OHCA action mentioned was call 999 (64.1%, n = 270/421) and 58.2% (n = 245/421) of participants reported that they would commence CPR. However, only 14.3% (n = 60/421) of participants spontaneously mentioned that they would locate an AED, while only 4.5% (n = 19/421) recounted that they would apply the AED. Just over half of participants (50.8%, n = 214/421) were first aid trained, with statistically more females (57.3%, n = 126/220) than males (43.9%,  n = 87/198) being first aiders (p = 0.01 χ2 = 7.41). Most participants (80.3%, n = 338/421) knew what an AED was, and 34.7% (n = 326/421) reported that they knew how to use one, however, only 11.9% (n = 50/421) mentioned that they would actually shock a patient. Being first aid trained increased the likelihood of freely recounting actions for OHCA and AED intervention. The most common barrier to helping during an OHCA was lack of knowledge (29.9%, n = 126/421). Although most participants reported they would know what to do during an OHCA and had knowledge of an AED, low numbers of participants spontaneously mentioned specific OHCA and AED actions. Improving public knowledge would help improve the public's confidence of intervening during an OHCA and may improve OHCA survival.

Sudden Cardiac Arrest in Basketball and Soccer Stadiums, the Role of Automated External Defibrillators: A Review. For the BELTRAN Study (BaskEtbaLl and soccer sTadiums: Registry on Automatic exterNal defibrillators)

Sudden cardiac arrest (SCA) during sports events has a dramatic impact on stadium-goers and the public and is often associated with poor outcomes unless treated with an automated external defibrillator (AED). Despite this, stadiums vary in AED use. This review aims to identify the risks and incidences of SCA, and the use of AEDs in soccer and basketball stadiums. A narrative review of all relevant papers was conducted. Athletes across all sports face an SCA risk of 1:50,000 athlete-years, with the greatest risk of SCA in young male athletes (1:35,000 person-years) and black male athletes (1:18,000 person-years). Africa and South America have the poorest soccer SCA outcomes at 3% and 4% survival. AED use on-site improves survival greater than defibrillation by emergency services. Many stadiums do not have AEDs implemented into medical plans and the AEDs are often unrecognisable or are obstructed. Therefore, AEDs should be used on-site, use clear signalling, have certified trained personnel, and be incorporated into stadiums' medical plans.

Out-of-hospital cardiac arrest in Africa: a scoping review

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is well studied in high-income countries, and research has encouraged the implementation of policy to increase survival rates. On the other hand, comprehensive research on OHCA in Africa is sparse, despite the higher incidence of risk factors. In this vein, structural barriers to OHCA care in Africa must be fully recognised and understood before similar improvements in outcome may be made. The aim of this study was to describe and summarise the body of literature related to OHCA in Africa.

METHODS AND ANALYSIS

Using an a priori developed search strategy, electronic searches were performed in Medline via Pubmed, Web of Science, Scopus and Google Scholar databases to identify articles published in English between 2000 and 2020 relevant to OHCA in Africa. Titles, abstract and full text were reviewed by two reviewers, with discrepancies handled by an independent reviewer. A summary of the main themes contained in the literature was developed using descriptive analysis on eligible articles.

RESULTS

A total of 1200 articles were identified. In the screening process, 785 articles were excluded based on title, and a further 127 were excluded following abstract review. During full-text review to determine eligibility, 80 articles were excluded and one was added following references review. A total of 19 articles met the inclusion criteria. During analysis, the following three themes were found: epidemiology and underlying causes for OHCA, first aid training and bystander action, and Emergency Medical Services (EMS) resuscitation and training.

CONCLUSIONS

In order to begin addressing OHCA in Africa, representative research with standardised reporting that complies to data standards is required to understand the full, context-specific picture. Policies and research may then target underlying conditions, improvements in bystander and EMS training, and system improvements that are contextually relevant and ultimately result in better outcomes for OHCA victims.

Optimizing Outcomes After Out-of-Hospital Cardiac Arrest With Innovative Approaches to Public-Access Defibrillation: A Scientific Statement From the International Liaison Committee on Resuscitation

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Optimizing outcomes after out-of-hospital cardiac arrest with innovative approaches to public-access defibrillation: A scientific statement from the International Liaison Committee on Resuscitation

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Evaluation of Autonomous Actions on Bystander-Initiated Cardiopulmonary Resuscitation and Public Access Defibrillation in Tokyo

The frequencies of autonomous bystander-initiated cardiopulmonary resuscitation (CPR) and public access defibrillation have not yet been clarified. We aimed to evaluate the frequency of autonomous actions by citizens not having a duty to act.This retrospective observational study included patients who suffered an out-of-hospital cardiac arrest (OHCA) in Tokyo between January 1, 2013 and December 31, 2017. The Delphi method with a panel of 11 experts classified the locations of OHCA resuscitations into 3 categories as follows; autonomous, non autonomous, and undetermined. The locations determined as autonomous were further divided into 2 groups; home and other locations. Bystander-initiated CPR and application of an automated external defibrillator (AED) pad were evaluated in 43,460 patients with OHCA.Group A (non autonomous), group B (autonomous, not home), and group C (home), consisted of 7,352, 3,193, and 32,915 patients, respectively. Compared with group A, group B and group C had significantly lower rates of bystander-initiated CPR (group A, B, C; 68.3% versus 38.6% versus 23.9%) and AED pad application (groups A, B, C; 26.8% versus 15.1% versus 0.6%). In addition, multivariate analysis demonstrated that an autonomous location of resuscitation was independently associated with the frequencies of bystander-initiated CPR and AED pad application, even after adjusting for age, sex, and witness status.Autonomous actions by citizens were unacceptably infrequent. Therefore, the education and training of citizens is necessary to further enhance autonomous CPR.

Which building types give optimal public access defibrillator coverage for out-of-hospital cardiac arrest?

INTRODUCTION

Public access defibrillation is a key component of the early links in the chain of survival. Despite growing numbers of PADs in the community, actual use remains poor, partly because of the difficulties in locating the nearest PAD. We aimed to establish the cover that would be provided if PADs were located in any given building type, which would enable the public to know where the nearest PAD was located.

METHODS

Mapping software was used to classify each and every building type in the South Central Ambulance Service region. The 52 commonest building types were then mapped to all cardiac arrest calls in the same geographical area from Jan 2014 - July 2018. The walking distance from each cardiac arrest to each nearest building type was calculated.

RESULTS

A total of 22,382 cardiac arrests were mapped to a total of 24,155 buildings considered suitable for potential PAD location. Post boxes ranked first in both urban and rural areas, covering 11.7% of cardiac arrests at 100 m and 85.6% of cardiac arrests at 500 m. In urban areas, bus shelters and telephone boxes also provided good coverage (9.7%, 9.5% @ 100 m; 69.2%, 71.9% @ 500 m respectively). In rural areas, good coverage was provided by nursing/care homes and pubs/bars (4.9%, 4.6% @ 100 m; 15.2%, 31.8% @ 500 m respectively).

CONCLUSION

Locating PADs at all post boxes would provide the most effective geographical coverage in both urban and rural areas according to building type. This may be an effective strategy to improve rapid PAD locating.

Assessment on CPR Knowledge and AED Availability in Saudi Malls by Security Personnel: Public Safety Perspective

Security personnel are the first ones who attend the scene in the case of out-of-hospital cardiac arrest (OHCA) at malls. Cardiopulmonary resuscitation (CPR) is not enough for those patients; they need an automated external defibrillator (AED) to bring the heart to function normally. This study aimed to assess the current status of CPR and AED knowledge and availability in Saudi malls by security personnel. Using a descriptive design, a study was conducted at seven malls located in the Eastern Province of Saudi Arabia. Two hundred and fifty participants were surveyed using the American Heart Association (AHA) 2015 guidelines to assess CPR and AED knowledge and availability in Saudi malls. The sample mean age was 32.60 years (SD = 10.02), and 87% of participants were working as security personnel. The majority of the participants had not received training about CPR and AED (75.8% and 95.2%, respectively). Common misconceptions are fallen into all categories of CPR and AED knowledge. Correctly answered statements ranged from 7.2% in the compression rate to 24.2% in hand placement. The study results indicated a poor training knowledge of CPR and AED in public settings. Integrating high-quality CPR and AED knowledge within the school and college curricula is a vital need. However, in order to maximize the survival rate, it is important to set laws and legislation adopted by stakeholders and decision makers to advocate the people who try to help, mandate AED installation in crowded places, and mandate teaching hands-only CPR and AED together as a package.

Public access of automated external defibrillators in a metropolitan city of China

BACKGROUND

Public access of automated external defibrillator (AED) is an important public health strategy for improving survival of cardiac arrest. Major metropolitan cities in China are increasingly investing and implementing public access defibrillator programs, but the effectiveness of these programs remains unclear. This study aims to evaluate the public accessibility of AED in Shanghai, a major metropolitan city in China.

METHODS

From July 1 to September 30, 2018, all AED locations indicated by AED Access Map Apps were visited and investigated in three most densely distributing areas of AED (Huangpu District, Xuhui District, and Central Area of the Pudong New District) in Shanghai. Two AED Access Map APPs were used to identify the location of AEDs. Characteristics of and the barriers to access, the AED sites were recorded. Awareness and skills of first aid and AED among on-site staff of the AED installation sites were evaluated.

RESULTS

A total of 283 sites were marked on two AED Apps. One hundred and seventy (60%) locations were accessible, and 142 (50%) were actually with AEDs installed. Among those AED installed sites, 112 (79%) were completely identifiable to the information on the maps, 20 (14%) were inconsistent and 10 (7%) were inaccurate on the maps. Ninety-four (66%) AEDs had visible signs and information around the location, 7 (5%) AEDs had signs outside of the location, and 107 (75%) sites had educational instructions. In addition, 230 individuals who were around the AED site were interviewed. Among them, 79 (34%) had good knowledge of AED. After shown the picture of AED, 112 (49%) knew whether there was AED in the site, and 108 (47%) knew the AED's location. Eighty-seven (38%) staff have received first aid training, and among them 26 (30%) reported that they had skills in operating the AED.

CONCLUSIONS

Public placement and accessibility of AEDs, related public signs and information on AED, and staff's awareness about AED were not optimal in Shanghai. Continuing efforts should be made to improve public accessibility and public awareness, knowledge, and user skills of AED.