ESC-ERC recommendations for the use of automated external defibrillators (AEDs) in Europe

Artificial Intelligence and Machine Learning Applications in Sudden Cardiac Arrest Prediction and Management: A Comprehensive Review

PURPOSE OF REVIEW

This literature review aims to provide a comprehensive overview of the recent advances in prediction models and the deployment of AI and ML in the prediction of cardiopulmonary resuscitation (CPR) success. The objectives are to understand the role of AI and ML in healthcare, specifically in medical diagnosis, statistics, and precision medicine, and to explore their applications in predicting and managing sudden cardiac arrest outcomes, especially in the context of prehospital emergency care.

RECENT FINDINGS

The role of AI and ML in healthcare is expanding, with applications evident in medical diagnosis, statistics, and precision medicine. Deep learning is gaining prominence in radiomics and population health for disease risk prediction. There's a significant focus on the integration of AI and ML in prehospital emergency care, particularly in using ML algorithms for predicting outcomes in COVID-19 patients and enhancing the recognition of out-of-hospital cardiac arrest (OHCA). Furthermore, the combination of AI with automated external defibrillators (AEDs) shows potential in better detecting shockable rhythms during cardiac arrest incidents. AI and ML hold immense promise in revolutionizing the prediction and management of sudden cardiac arrest, hinting at improved survival rates and more efficient healthcare interventions in the future. Sudden cardiac arrest (SCA) continues to be a major global cause of death, with survival rates remaining low despite advanced first responder systems. The ongoing challenge is the prediction and prevention of SCA. However, with the rise in the adoption of AI and ML tools in clinical electrophysiology in recent times, there is optimism about addressing these challenges more effectively.

Network of Automated External Defibrillators in Poland before the SARS-CoV-2 Pandemic: An In-Depth Analysis

Introduction: Sudden cardiac arrest (SCA), which causes more than half of all cardiovascular related deaths, can be regarded as a common massive global public health problem. Analyzing out-of-hospital cardiac arrest (OHCA) cases, one of the key components is automatic external defibrillators (AEDs). Aim: The aim of this study was to analyze the use and distribution of AEDs in Polish public places. Materials and methods: The data were analyzed by using the Excel and R calculation programs. Results: The data represents 120 uses of automatic external defibrillators used in Polish public space in the period 2008–2018. The analysis describes 1165 locations of AEDs in Poland. It was noted that the number of uses in the period 2010–2016 fluctuated at a constant value, with a significant rise in 2017. When analyzing the time of interventions in detail the following was noted: the highest percentage of interventions was observed in April, and the lowest in November; the highest number of interventions was observed on a Friday, while the least number of interventions was observed on a Sunday; most occurred between 12:00 to 16:00, and least between 20:00 to 8:00. Conclusions: The observed growth in the number of cases of AED use in public places is associated with the approach to training, the emphasis on public access to defibrillation, and, therefore, the growth of social awareness. This study will be continued. The next analysis would include 2020–2022 and would be a comparative analysis with the current research.

Role of artificial intelligence in defibrillators: a narrative review

Automated external defibrillators (AEDs) and implantable cardioverter defibrillators (ICDs) are used to treat life-threatening arrhythmias. AEDs and ICDs use shock advice algorithms to classify ECG tracings as shockable or non-shockable rhythms in clinical practice. Machine learning algorithms have recently been assessed for shock decision classification with increasing accuracy. Outside of rhythm classification alone, they have been evaluated in diagnosis of causes of cardiac arrest, prediction of success of defibrillation and rhythm classification without the need to interrupt cardiopulmonary resuscitation. This review explores the many applications of machine learning in AEDs and ICDs. While these technologies are exciting areas of research, there remain limitations to their widespread use including high processing power, cost and the ‘black-box’ phenomenon.

Trends in maintenance status and usability of public automated external defibrillators during a 5-year on-site inspection

This study aimed to assess the trend of the maintenance status and usability of public automated external defibrillators (AEDs). Public AEDs installed in Seoul from 2013 to 2017 were included. An inspector checked the maintenance status and usability of the AEDs annually using a checklist. During the study period, 23,619 AEDs were inspected. Access to the AEDs was improved, including the absence of obstacles near the AEDs (from 90.2% in 2013 to 99.1% in 2017, p < 0.0001) and increased AED signs (from 34.3% in 2013 to 91.3% in 2017, p < 0.0001). The rate of AEDs in normal operation (from 94.0% in 2013 to 97.6% in 2017, p < 0.0001), good battery status (from 95.6% in 2013 to 96.8% in 2017, p = 0.0016), and electrode availability increased (from 97.1% in 2013 to 99.0% in 2017, p < 0.0001); the rate of electrode validity decreased (from 90.0% in 2013 to 87.2% in 2017, p < 0.0001). The overall rate of the non-ready-to-use AEDs and AEDs with less than 24-h usability accounted for 15.4% and 44.1% of the total number of AEDs, respectively. Although most AEDs had a relatively good maintenance status, a significant proportion of public AEDs were not available for 24-h use. Invalid electrodes and less than 24-h accessibility were the main reasons that limited the 24-h usability of public AEDs.

Cardiac deatH prevention by aUtomated defibrillatoRs in ChurcHes: rationale and design of the CHURCH trial

Early defibrillation programs by the use of automated external defibrillators (AEDs) located in high-attendance public places may improve survival and neurologic outcome of patients undergoing sudden cardiac arrest (SCA). We planned a prospective cohort study to assess the effectiveness of a public-access defibrillation program based on positioning of AEDs in churches and training of lay volunteers in Basic Life Support Defibrillation during a single-day 5-hour training session. The CHURCH project aims to promote a widespread diffusion of AEDs, to train a large number of lay volunteers in Basic Life Support Defibrillation, and to increase population awareness on the opportunities for sudden death prevention. The rationale of the study rests on a survey commissioned by the Diocese of Milan that found a high prevalence of elderly subjects (44.5% were >60 years old) attending holy services in the morning hours, when sudden death incidence peaks. The catchment areas of the 12 parishes included in the trial as of June 2008 include a population of 140,000. The projected incidence of AED-treatable SCA, based on the presence of trained volunteers in the churches during day hours, at the CHURCH participating sites was estimated at 8 episodes per year. To estimate an overall 30% mortality reduction from SCA after AED placement at the study sites with respect to conventional SCA management by the Emergency Medical Service, 25 SCA episodes will have to be treated during the 4-year study period. The CHURCH project might be of interest and applicable in every country where high-attendance worship places are present.

A national scheme for public access defibrillation in England and Wales: early results

BACKGROUND

Automated external defibrillators (AEDs) operated by lay persons are used in the UK in a National Defibrillator Programme promoting public access defibrillation (PAD).

METHODS

Two strategies are used: (1) Static AEDs installed permanently in busy public places operated by those working nearby. (2) Mobile AEDs operated by community first responders (CFRs) who travel to the casualty.

RESULTS

One thousand five hundred and thirty resuscitation attempts. With static AEDs, return of spontaneous circulation (ROSC) was achieved in 170/437 (39%) patients, hospital discharge in 113/437 (26%). With mobile AEDs, ROSC was achieved in 110/1093 (10%), hospital discharge in 32 (2.9%) (P<0.001 for both variables). More shocks were administered with static AEDS 347/437 (79%) than mobile AEDs 388/1093 (35.5%) P<0.001. Highly significant advantages existed for witnessed arrests, administration of shocks, bystander CPR before arrival of AED and short delays to start CPR and attach AED. These factors were more common with static AEDs. For CFRs, patients at home did less well than those at other locations for ROSC (P<0.001) and survival (P=.006). Patients at home were older, more arrests were unwitnessed, fewer shocks were given, delays to start CPR and attach electrodes were longer.

CONCLUSIONS

PAD is a highly effective strategy for patients with sudden cardiac arrest due to ventricular fibrillation who arrest in public places where AEDs are installed. Community responders who travel with an AED are less effective, but offer some prospect of resuscitation for many patients who would otherwise receive no treatment. Both strategies merit continuing development.

Usefulness of emergency medical teams in sport stadiums

In August 2006, the new AZ Alkmaar soccer stadium (capacity 17,000) opened. To provide adequate emergency support, medical teams of Red Cross volunteers and coronary care unit and emergency room nurses were formed, and facilities including automated external defibrillators were made available at the stadium. During every match, 3 teams are placed among the spectators. All patients who had cardiac events were stabilized by the teams and transported to the hospital. They formed the study group. From August 2006 to May 2007, >800,000 individuals attended soccer matches at the new stadium. Four cardiac events (3 out-of-hospital-resuscitations for ventricular fibrillation, 1 patient with chest pain) requiring emergency medical support occurred. On-site resuscitations using defibrillators were successful. Two patients with triple-vessel disease subsequently underwent coronary bypass surgery and implantable cardioverter-defibrillator implantation. One patient had single-vessel disease of the circumflex branch, for which he received a coronary stent. All had uneventful recoveries. An acute coronary syndrome was ruled out in the patient presenting with chest pain. In conclusion, the presence of emergency medical teams at a large sport stadium was of vital importance in the immediate care of critically ill patients. On-site resuscitation using automated external defibrillators was lifesaving in all cases. The presence of medical teams equipped with defibrillators and emergency action plans is recommended at large venues that host sports and other activities.

[Public access defibrillation. Limited use by trained first responders and laymen]

As ventricular fibrillation is the most frequent initial heart rhythm causing out-of-hospital sudden cardiac arrest, defibrillation is of essential significance. Automated external defibrillators (AEDs) have been available for some years and as a result defibrillation can be carried out by individuals other than physicians and healthcare providers such as trained first responders and untrained lay rescuers. This so-called public access defibrillation nourished hope of progress in the treatment of sudden cardiac arrest. However, several limitations exist, such as low frequency of sudden cardiac arrest in public, rare use of publicly placed AEDs, low cost effectiveness, legal requirements and insufficient public willingness to help. Due to these restrictions of public access defibrillation other measures are more promising than the attempt at general distribution of AEDs. These measures are primary or secondary prophylaxis of sudden cardiac arrest, general knowledge of adequate activation of emergency medical services, implementation of first responder teams equipped with AEDs and particularly a better education in and application of the well-established principles of cardiopulmonary resuscitation.

Optimal refresher training intervals for AED and CPR skills: A randomised controlled trial

AIM

To determine the optimal refresher training interval for lay volunteer responders in the English National Defibrillator Programme who had previously undertaken a conventional 4-h initial class and a first refresher class at 6 months.

METHODS

Subjects were randomised to receive either two additional refresher classes at intervals of 7 and 12 months or one additional refresher class after 12 months.

RESULTS

Greater skill loss had occurred when the second refresher class was undertaken at 12 compared with 7 months. Skill retention however, was higher in the former group, ultimately resulting in no significant difference in final skill performance. There was no significant difference in performance between subjects attending two versus three refresher classes. On completion of refresher training all subjects were able to deliver countershocks, time to first shock decreased by 17s in both groups, and the proportion of subjects able to perform most skills increased. The execution of several important interventions remained poor, regardless of the total number of classes attended or the interval between them. These included CPR skills, defibrillation pad placement, and pre-shock safety checks. Refresher classes held more frequently and at shorter intervals increased subjects' self-assessed confidence, possibly indicating greater preparedness to use an AED in a real emergency.

CONCLUSIONS

This study shows that the ability to deliver countershocks is maintained whether the second refresher class is held at seven or 12 months after the first. To limit skill deterioration between classes, however, refresher training intervals should not exceed 7 months. The quality of instruction given should be monitored carefully. Learning and teaching strategies require review to improve skill acquisition and maintenance.

Home defibrillation: a feasibility study in myocardial infarction survivors at intermediate risk of sudden death

BACKGROUND

Out-of-hospital cardiac arrest occurs at home in 65-80% of cases and is often witnessed. We designed a study to explore the feasibility of a home defibrillation program (a) evaluating the retention of cardiopulmonary resuscitation and automated external defibrillators (AED) use skills (BLSD) (b) assessing the impact on anxiety, depression, and quality of life and (c) recording the critical issues emerging from program implementation.

METHODS

Thirty-three post-myocardial infarction patients and their 56 relatives received BLSD training and an AED. Assessment of BLSD skills, levels of anxiety, and depression and quality of life were scheduled every 3 months for 1 year or until a common stopping date.

RESULTS

Overall BLSD score was 26 +/- 3 at baseline vs. 22 +/- 5 at 3 months (P < .0001), 21 +/- 6 at 6 months (P < .0001), 22 +/- 4 at 9 months (P < .0001) and 23 +/- 5 at 12 months (P = .001). Conversely, the BLSD component AED use" remained stable throughout the study. Quality of life, anxiety, and depression scores remained constant. Compliance to BLSD retraining sessions and AEDs checks decreased over time and was influenced by a concomitant clinical appointment.

CONCLUSIONS

BLSD performance of families of post-myocardial infarction patients decreases over time, even though the ability to operate AEDs appears to be the least affected component. Compliance with retraining sessions and AED checks declines over time and is improved if they are combined with clinical appointments. The implementation of a home defibrillation program does not affect anxiety, depression, or the quality of life.

Moderate sea states do not influence the application of an AED in rigid inflatable boats

PURPOSE

This study was to determine if the AED can be operated correctly on board rigid inflatable rescue boats (RIBs), and if downloading of data later for quality control is possible.

METHODS

Six AEDs were tested for their reliability, robustness and stability. Data were collected on three different types of RIBs, in a harbour and at sea. Each AED was connected to a volunteer and a manikin simulating VF. Data from the AED were continuously collected.

RESULTS

At one of the RIBs each AED became wet; no AED had a technical problem. When connected to the volunteer, the ECGs delivered by the AEDs showed a regular sinus rhythm. When connected to a manikin in VF, each AED was able to recognise VF and to provide a shock. There were differences in the time between first analysis and the shock. The voice prompt of the Zoll AED Plus was 'understandable', while the other AEDs were 'difficult to understand'. We had a problem with the infrared connection, which means that evaluation and quality control afterwards may be difficult.

CONCLUSION

The use of AEDs on RIBs during patient transport over calm water is possible and effective. The AED should have a screen and better features to download data. However, AEDs are only worthwhile when they fit well in the Chain of Survival (fast arrival, immediately availability of an AED, trained provider and advanced life support).

A reference automated external defibrillator provider course for Europe

BACKGROUND

Scientific evidence is scarce in relation to the effectiveness of different methods of teaching automated external defibrillator (AED) use to laypeople. A reference course is needed in order to test new courses or methods against a comparative standard.

OBJECTIVE

To propose a reference AED provider course that can be used as a comparator when testing new courses or teaching methods.

METHODS

All national resuscitation councils that are represented in the European Resuscitation Council were sent a questionnaire about the AED provider courses run by them or under their auspices.

RESULTS

Sixteen national resuscitation councils responded to the enquiry. Apart from the individual course timetables, there was remarkable consistency amongst the European countries as regards organisation, structure, content and methods.

CONCLUSIONS

A reference AED provider course for laypeople, based on a synthesis of existing European courses, is suggested as a tool for research. Prior completion of a basic life support provider course is mandatory. Course duration is 2 h 45 min (excluding breaks), with 1 h 40 min practice time for the participants, 25 min for theory, 20 min for practical demonstrations by the instructor and 20 min for introduction, discussion and closure. A manual is distributed at the start of the course. The ratio of instructors to participants is one to six. Lectures are interactive between the instructor and the class. AED use is practised in groups of six participants. Participants prove their competency by means of a formal test that simulates a cardiac arrest scenario. Using this course as a comparator during research into the methodology of AED teaching would provide a reference against which other courses could be tested.

Future shock: automatic external defibrillators

PURPOSE OF REVIEW

This review provides a practical overview of the performance capabilities of automatic external defibrillators (AEDs), and of advances in technology and dissemination programmes for these devices.

RECENT FINDINGS

Arrhythmia analysis by AEDs is extremely reliable in most settings (sensitivity 81-100%, specificity 99.9-97.6%). Accurate detection of arrhythmias has also been demonstrated in children, leading the US Food and Drug Administration to approve the use of several AEDs in children aged 8 years or younger. Factors that potentially may reduce the quality of arrhythmia detection are the presence of wide complex supraventricular tachycardia and location of an arrythmic event near to high-power lines. AED use by professional basic life support providers resulted in increased survival in the prehospital setting. However, provision of AEDs to nonmedical rescue services did not result in universal improvement in patient outcome. Public access defibrillation programmes have led to higher rates of survival from cardiac arrest. The role of AEDs in hospitals has yet to be elucidated, although in-hospital mortality from ventricular arrhythmias has been shown to decrease following AED deployment.

SUMMARY

Given the correct setting, AEDs can ensure that defibrillation is not limited by lack of medical knowledge or difficulties in decision making. However, event-related variables and operator-related factors, that are yet to be determined, can significantly affect the efficacy of automatic external defibrillation.

Demographic and temporal trends in out of hospital sudden cardiac death in Belfast

OBJECTIVE

To determine the epidemiology of out of hospital sudden cardiac death (OHSCD) in Belfast from 1 August 2003 to 31 July 2004.

DESIGN

Prospective examination of out of hospital cardiac arrests by using the Utstein style and necropsy reports. World Health Organization criteria were applied to determine the number of sudden cardiac deaths.

RESULTS

Of 300 OHSCDs, 197 (66%) in men, mean age (SD) 68 (14) years, 234 (78%) occurred at home. The emergency medical services (EMS) attended 279 (93%). Rhythm on EMS arrival was ventricular fibrillation (VF) in 75 (27%). The call to response interval (CRI) was mean (SD) 8 (3) minutes. Among patients attended by the EMS, 9.7% were resuscitated and 7.2% survived to leave hospital alive. The CRI for survivors was mean (SD) 5 (2) minutes and for non-survivors, 8 (3) minutes (p < 0.001). Ninety one (30%) OHSCDs were witnessed; of these 91 patients 48 (53%) had VF on EMS arrival. The survival rate for witnessed VF arrests was 20 of 48 (41.7%): all 20 survivors had VF as the presenting rhythm and CRI < or = 7 minutes. The European age standardised incidence for OHSCD was 122/100,000 (95% confidence interval 111 to 133) for men and 41/100,000 (95% confidence interval 36 to 46) for women.

CONCLUSION

Despite a 37% reduction in heart attack mortality in Ireland over the past 20 years, the incidence of OHSCD in Belfast has not fallen. In this study, 78% of OHSCDs occurred at home.

Prospective assessment of integrating the existing emergency medical system with automated external defibrillators fully operated by volunteers and laypersons for out-of-hospital cardiac arrest: the Brescia Early Defibrillation Study (BEDS)

AIMS

There are few data on the outcomes of cardiac arrest (CA) victims when the defibrillation capability of broad rural and urban territories is fully operated by volunteers and laypersons.

METHODS AND RESULTS

In this study, we investigated whether a programme based on diffuse deployment of automated external defibrillators (AEDs) operated by 2186 trained volunteers and laypersons across the County of Brescia, Italy (area: 4826 km(2); population: 1 112 628), would safely and effectively impact the current survival among victims of out-of-hospital CA. Forty-nine AEDs were added to the former emergency medical system that uses manual EDs in the emergency department of 10 county hospitals and in five medically equipped ambulances. The primary endpoint was survival free of neurological impairment at 1-year follow-up. Data were analysed in 692 victims before and in 702 victims after the deployment of the AEDs. Survival increased from 0.9% (95% CI 0.4-1.8%) in the historical cohort to 3.0% (95% CI 1.7-4.3%) (P=0.0015), despite similar intervals from dispatch to arrival at the site of collapse [median (quartile range): 7 (4) min vs. 6 (6) min]. Increase of survival was noted both in the urban [from 1.4% (95% CI 0.4-3.4 %) to 4.0% (95% CI 2.0-6.9 %), P=0.024] and in the rural territory [from 0.5% (95% CI 0.1-1.6%) to 2.5% (95% CI 1.3-4.2%), P=0.013]. The additional costs per quality-adjusted life year saved amounted to euro39 388 (95% CI euro16 731-49 329) during the start-up phase of the study and to euro23 661 (95% CI euro10 327-35 528) at steady state.

CONCLUSION

Diffuse implementation of AEDs fully operated by trained volunteers and laypersons within a broad and unselected environment proved safe and was associated with a significantly higher long-term survival of CA victims.

[First responder defibrillation in the LAGO-die Therme--results and experiences]

The use of automated external defibrillator (AED) by persons other than paramedics and emergency medical technicians is advocated by several US- and European organizations. However, at the present time it is still unclear to identify public places with a high incidence of out-of-hospital cardiac arrest. There are few data on the potential impact of public access defibrillators on survival after out-of-hospital cardiac arrest in sporting arenas or water parks. Therefore, we studied prospectively incidence of out-of-hospital cardiac arrest in the LAGO-die Therme in Herne. This is one of the most important swimming parks in Europe and member of the European Waterpark Association EWA. Eight AEDs were placed in the waterpark LAGO-die Therme. The locations where the defibrillators were stored were chosen to make possible a target interval of 60 seconds from collapse to first defibrillation. Twenty waterpark officers were instructed in cardiopulmonary resuscitation and in the use of the AED. During November 16, 2001 and December 31, 2004, 2.05 Mio. visitors were counted in the LAGO. Out-of-hospital cardiac arrest occurred in none of them. AED were used in two visitors with non arrhythmogenic syncope, no shock was delivered. Questionaires were done in 588 visitors (336 males, 252 females, mean age 38+21 years) in 2002 and in 579 visitors (322 males, 257 females, mean age 37+/-25 years) in 2004. In 2002, 77% of the visitors noticed the AED and, therefore, 49% performed more sporting activities. In addition, in 2004, AED was noticed by 480 visitors (83%) and 277 visitors (48%) did more sporting activities. There were no significant differences between 2002 and 2004 (p=ns). Despite no out-of-hospital cardiac arrest in the waterpark during the 3 year follow- up, it seems reasonable to install AED in sporting places with thousands of visitors per year.