Survival after Public Access Defibrillation in Stockholm, Sweden – A striking success

Drone delivery of automated external defibrillators compared with ambulance arrival in real-life suspected out-of-hospital cardiac arrests: a prospective observational study in Sweden

BACKGROUND

A novel approach to improve bystander defibrillation for out-of-hospital cardiac arrests is to dispatch and deliver an automated external defibrillator (AED) directly to the suspected cardiac arrest location by drone. The aim of this study was to investigate how often a drone could deliver an AED before ambulance arrival and to measure the median time benefit achieved by drone deliveries.

METHODS

In this prospective observational study, five AED-equipped drones were placed within two separate controlled airspaces in Sweden, covering approximately 200 000 inhabitants. Drones were dispatched in addition to standard emergency medical services for suspected out-of-hospital cardiac arrests and flight was autonomous. Alerts concerning children younger than 8 years, trauma, and emergency medical services-witnessed cases were not included. Exclusion criteria were air traffic control non-approval of flight, unfavourable weather conditions, no-delivery zones, and darkness. Data were collected from the dispatch centres, ambulance organisations, Swedish Registry for Cardiopulmonary Resuscitation, and the drone operator. Core outcomes were the percentage of cases for which an AED was delivered by a drone before ambulance arrival, and the median time difference (minutes and seconds) between AED delivery by drone and ambulance arrival. Explorative outcomes were percentage of attached drone-delivered AEDs before ambulance arrival and the percentage of cases defibrillated by a drone-delivered AED when it was used before ambulance arrival.

FINDINGS

During the study period (from April 21, 2021 to May 31, 2022), 211 suspected out-of-hospital cardiac arrest alerts occurred, and in 72 (34%) of those a drone was deployed. Among those, an AED was successfully delivered in 58 (81%) cases, and the major reason for non-delivery was cancellation by dispatch centre because the case was not an out-of-hospital cardiac arrest. In cases for which arrival times for both drone and ambulance were available (n=55), AED delivery by drone occurred before ambulance arrival in 37 cases (67%), with a median time benefit of 3 min and 14 s. Among these cases, 18 (49%) were true out-of-hospital cardiac arrests and a drone-delivered AED was attached in six cases (33%). Two (33%) had a shockable first rhythm and were defibrillated by a drone-delivered AED before ambulance arrival, with one person achieving 30-day survival. No adverse events occurred. AED delivery (not landing) was made within 15 m from the patient or building in 91% of the cases.

INTERPRETATION

AED-equipped drones dispatched in cases of suspected out-of-hospital cardiac arrests delivered AEDs before ambulance arrival in two thirds of cases, with a clinically relevant median time benefit of more than 3 min. This intervention could potentially decrease time to attachment of an AED, before ambulance arrival.

FUNDING

Swedish Heart Lung Foundation.

Effects of a volunteer responder system for out-of-hospital cardiac arrest in areas of different population density - A retrospective cohort study

BACKGROUND

Volunteer responder dispatch to nearby out-of-hospital cardiac arrests using a smartphone application can increase the proportion of patients receiving cardiopulmonary resuscitation. It is unknown how population density is related to the efficacy of a volunteer responder system. This study aimed to compare the response time of volunteer responders and EMS dispatched to suspected OHCAs in areas of different population density.

METHODS

A total of 2630 suspected OHCAs in Stockholm County during 2018-2020 where at least one dispatched volunteer responder reached the patient were identified through the HeartRunner™ application database. Study outcome was the proportion of cases where volunteer responders arrived at the scene before EMS, as well as the difference in time between the arrival of volunteer responders and EMS.

RESULTS

Volunteer responders arrived before EMS in 68% of examined cases (n = 1613). Higher population density was associated with a lower proportion of cases where volunteer responders arrived at the scene before EMS. Time on scene before arrival of EMS was highest in areas of low population density and averaged 4:07 (mm:ss). Response time was significantly shorter for volunteer responders compared to EMS across all population density groups at 4:47 vs 8:11 (mm:ss) (p < 0.001); the largest difference in response time was found in low population density areas.

CONCLUSION

Volunteer responders have significantly shorter response time than EMS regardless of population density, with the greatest difference in low population density areas. Although their impact on clinical outcome remains unknown, the benefits of dispatching volunteer responders to OHCAs may be greatest in rural areas.

The Role of Automated External Defibrillator Use in the Out-of-Hospital Cardiac Arrest Survival Rate and Outcome: A Systematic Review

Out-of-hospital cardiac arrest (OHCA) remains a significant cause of death. The chance of survival significantly increases when immediate defibrillation with an on-site automated external defibrillator (AED) is available. Our aim is to systematically evaluate the impact of public access defibrillators (PAD) on the outcomes of outpatient cardiac arrest. We conducted a systematic review of the data from global studies on the role of bystander and emergency medical service (EMS) interventions, primarily focusing on the usage of AEDs, during OHCA events. The results highlight the critical significance of PADs in improving survival outcomes in OHCA settings. The majority of OHCA incidents occurred in private residences, but public spaces such as schools and airports had better outcomes, likely due to AED accessibility and trained individuals. Placing AEDs in public areas, especially high-risk zones, can boost survival chances. Timely defibrillation, particularly by bystanders, correlated with better survival and neurological conditions. The review emphasizes the importance of widespread cardiopulmonary resuscitation (CPR) and AED training, strategic AED placement, and continuous monitoring of interventions and outcomes to enhance survival rates and neurological recovery after OHCAs. This systematic review showed that bystander interventions, including CPR and AED usage, significantly increased the survival rate. Overall, immediate response and accessibility to AEDs in public areas can significantly improve outcomes in OHCA events.

Dispatch of Volunteer Responders to Out-of-Hospital Cardiac Arrests

BACKGROUND

Systems for dispatch of volunteer responders to collect automated external defibrillators and/or to provide cardiopulmonary resuscitation (CPR) in cases of nearby out-of-hospital cardiac arrest (OHCA) are widely implemented.

OBJECTIVES

This study aimed to investigate whether the activation of a volunteer responder system to OHCAs was associated with higher rates of bystander CPR, bystander defibrillation, and 30-day survival vs no system activation.

METHODS

This was a retrospective observational analysis within the ESCAPE-NET (European Sudden Cardiac Arrest network: Towards Prevention, Education, New Effective Treatment) collaborative research network. Included were cases of OHCA between 2015 and 2019 from 5 European sites with volunteer responder systems. At all sites, systems were activated by dispatchers at the emergency medical communication center in response to suspected OHCA. Exposed cases (system activation) were compared with nonexposed cases (no system activation). Risk ratios (RRs) were calculated for the outcomes of bystander CPR, bystander defibrillation, and 30-day survival after inverse probability treatment weighting. Missing data were handled using multiple imputation.

RESULTS

In total, 9,553 cases were included. In 4,696 cases, the volunteer responder system was activated, and in 4,857 it was not. The pooled RRs were 1.30 (95% CI: 1.15-1.47) for bystander CPR, 1.89 (95% CI: 1.36-2.63) for bystander defibrillation, and 1.22 (95% CI: 1.07-1.39) for 30-day survival.

CONCLUSIONS

Activation of a volunteer response system in cases of OHCA was associated with a higher chance of bystander CPR, bystander defibrillation, and 30-day survival vs no system activation. A randomized controlled trial is necessary to determine fully the causal effect of volunteer responder systems.

Community First Responders' Contribution to Emergency Medical Service Provision in the United Kingdom

STUDY OBJECTIVE

We aimed to investigate community first responders' contribution to emergency care provision in terms of number, rate, type, and location of calls and characteristics of patients attended.

METHODS

We used a retrospective observational design analyzing routine data from electronic clinical records from 6 of 10 ambulance services in the United Kingdom during 2019. Descriptive statistics, including numbers and frequencies, were used to illustrate characteristics of incidents and patients that the community first responders attended first in both rural and urban areas.

RESULTS

The data included 4.5 million incidents during 1 year. The community first responders first attended a higher proportion of calls in rural areas compared with those in urban areas (3.90% versus 1.48 %). In rural areas, the community first responders also first attended a higher percentage of the most urgent call categories, 1 and 2. The community first responders first attended more than 9% of the total number of category 1 calls and almost 5% of category 2 calls. The community first responders also attended a higher percentage of the total number of cardiorespiratory and neurological/endocrine conditions. They first attended 6.5% of the total number of neurological/endocrine conditions and 5.9% of the total number of cardiorespiratory conditions. Regarding arrival times in rural areas, the community first responders attended higher percentages (more than 6%) of the total number of calls that had arrival times of less than 7 minutes or more than 60 minutes.

CONCLUSION

In the United Kingdom, community first responders contribute to the delivery of emergency medical services, particularly in rural areas and especially for more urgent calls. The work of community first responders has expanded from their original purpose-to attend to out-of-hospital cardiac arrests. The future development of community first responders' schemes should prioritize training for a range of conditions, and further research is needed to explore the contribution and potential future role of the community first responders from the perspective of service users, community first responders' schemes, ambulance services, and commissioners.

Effect of Smartphone Dispatch of Volunteer Responders on Automated External Defibrillators and Out-of-Hospital Cardiac Arrests: The SAMBA Randomized Clinical Trial

Importance

Smartphone dispatch of volunteer responders to nearby out-of-hospital cardiac arrests (OHCAs) has emerged in several emergency medical services, but no randomized clinical trials have evaluated the effect on bystander use of automated external defibrillators (AEDs).

Objective

To evaluate if bystander AED use could be increased by smartphone-aided dispatch of lay volunteer responders with instructions to collect nearby AEDs compared with instructions to go directly to patients with OHCAs to start cardiopulmonary resuscitation (CPR).

Design, Setting, and Participants

This randomized clinical trial assessed a system for smartphone dispatch of volunteer responders to individuals experiencing OHCAs that was triggered at emergency dispatch centers in response to suspected OHCAs and randomized 1:1. The study was conducted in 2 main Swedish regions: Stockholm and Västra Götaland between December 2018 and January 2020. At study start, there were 3123 AEDs in Stockholm and 3195 in Västra Götaland and 24 493 volunteer responders in Stockholm and 19 117 in Västra Götaland. All OHCAs in which the volunteer responder system was activated by dispatchers were included. Excluded were patients with no OHCAs, those with OHCAs not treated by the emergency medical services, and those with OHCAs witnessed by the emergency medical services.

Interventions

Volunteer responders were alerted through the volunteer responder system smartphone application and received map-aided instructions to retrieve nearest available public AEDs on their way to the OHCAs. The control arm included volunteer responders who were instructed to go directly to the OHCAs to perform CPR.

Main Outcomes and Measures

Overall bystander AED attachment, including those attached by volunteer responders and lay volunteers who did not use the smartphone application.

Results

Volunteer responders were activated for 947 patients with OHCAs. Of those, 461 were randomized to the intervention group (median [IQR] age of patients, 73 [61-81] years; 295 male patients [65.3%]) and 486 were randomized to the control group (median [IQR] age of patients, 73 [63-82] years; 312 male patients [65.3%]). Primary outcome of AED attachment occurred in 61 patients (13.2%) in the intervention arm vs 46 patients (9.5%) in the control arm (difference, 3.8% [95% CI, -0.3% to 7.9%]; P = .08). The majority of AEDs were attached by lay volunteers who were not using the smartphone application (37 in intervention arm, 28 in control). There were no significant differences in secondary outcomes. Among the volunteer responders using the application, crossover was 11% and compliance to instructions was 31%. Volunteer responders attached 38% (41 of 107) of all AEDs and provided 45% (16 of 36) of all defibrillations and 43% (293 of 666) of all CPR.

Conclusions and Relevance

In this study, smartphone dispatch of volunteer responders to OHCAs to retrieve nearby AEDs vs instructions to directly perform CPR did not significantly increase volunteer AED use. High baseline AED attachement rate and crossover may explain why the difference was not significant.

Trial Registration

ClinicalTrials.gov Identifier: NCT02992873.

Are first responders first? The rally to the suspected out-of-hospital cardiac arrest

BACKGROUND

Time is the crucial factor in the "chain of survival" treatment concept for out-of-hospital cardiac arrest (OHCA). We aimed to measure different response time intervals by comparing emergency medical system (EMS), fire fighters and smartphone aided volunteer responders.

METHODS

In two large Swedish regions, volunteer responders were timed from the alert until they arrived at the scene of the suspected OHCA. The first arriving volunteer responders who tried to fetch an automated external defibrillator (AED-responder) and who ran to perform bystander cardiopulmonary resuscitation (CPR-responder) were compared to both the first arriving EMS and fire fighters. Three-time intervals were measured, from call to dispatch, the unit response time (from dispatch to arrival) and the total response time.

RESULTS

During 22 months, 2631 suspected OHCAs were included. The median time from call to dispatch was in minutes 1.8 (95% CI = 1.7-1.8) for EMS, 2.9 (95% CI = 2.8-3.0) for fire-fighters and 3.0 (95% CI = 2.9-3.1) for volunteer responders. The median unit response time was 8.3 (95% CI = 8.1-8.5) for EMS, 6.8 (95% CI = 6.7-6.9) for fire fighters and 6.0 (95% CI = 5.7-6.2) for AED-responders and 4.6 (95% CI = 4.5-4.8) for CPR-responders. The total response time was 10.4 (95% CI = 10.1-10.6) for EMS, 10.2 (95% CI = 9.9-10.4) for fire fighters, 9.6 (95% CI = 9.1-9.8) for AED-responders and 8.2 (95% CI = 8.0-8.3) for CPR-responders.

CONCLUSION

First arriving volunteer responders had the shortest unit response time when compared to both fire fighters and EMS, however this advantage was reduced by delays introduced at the dispatch center. Earlier automatic dispatch should be considered in further studies.

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.

Swedish dispatchers’ compliance with the American Heart Association performance goals for dispatch-assisted cardiopulmonary resuscitation and its association with survival in out-of-hospital cardiac arrest: A retrospective study

Aim

We aimed 1) to investigate how Swedish dispatchers perform during emergency calls in accordance with the American Heart Association (AHA) goals for dispatcher-assisted cardiopulmonary resuscitation (DA-CPR), 2) calculate the potential impact on 30-day survival.

Methods

This observational study includes a random sample of 1000 out-of-hospital cardiac arrest (OHCA) emergency ambulance calls during 2018 in Sweden. Voice logs were audited to evaluate dispatchers’ handling of emergency calls according to the AHA performance goals. Number of possible additional survivors was estimated assuming the timeframes of the AHA performance goals was achieved.

Results

A total of 936 cases were included. An OHCA was recognized by a dispatcher in 79% (AHA goal 75%). In recognizable OHCA, dispatchers recognized 85% (AHA goal 95%). Dispatch-directed compressions were given in 61% (AHA goal 75%). Median time to OHCA recognition was 113 s [interquartile range (IQR), 62, 204 s] (AHA goal < 60 s). The first dispatch-directed compression was performed at a median time of 240 s [IQR, 176, 332 s] (AHA goal < 90 s). If eligible patients receive dispatch-directed compressions within the AHA 90 s goal, 73 additional lives may be saved; if all cases are recognized within the AHA 60 s goal, 25 additional lives may be saved.

Conclusions

The AHA policy statement serves as a benchmark for all emergency medical dispatch centres (EMDC). Additional effort is needed at Swedish EMDC to achieve AHA goals for DA-CPR. Our study suggests that if EMDC further optimize handling of OHCA calls in accordance with AHA goals, many more lives may be saved.

The Automated External Defibrillator: Heterogeneity of Legislation, Mapping and Use across Europe. New Insights from the ENSURE Study

INTRODUCTION

The rapid use of an automated external defibrillator (AED) is crucial for increased survival after an out-of-hospital cardiac arrest (OHCA). Many factors could play a role in limiting the chance of an AED use. We aimed to verify the situation regarding AED legislation, the AED mapping system and first responders (FRs) equipped with an AED across European countries.

METHODS

We performed a survey across Europe entitled "European Study about AED Use by Lay Rescuers" (ENSURE), asking the national coordinators of the European Registry of Cardiac Arrest (EuReCa) program to complete it.

RESULTS

Nineteen European countries replied to the survey request for a population covering 128,297,955 inhabitants. The results revealed that every citizen can use an AED in 15 countries whereas a training certificate was required in three countries. In one country, only EMS personnel were allowed to use an AED. An AED mapping system and FRs equipped with an AED were available in only 11 countries. The AED use rate was 12-59% where AED mapping and FR systems were implemented, which was considerably higher than in other countries (0-7.9%), reflecting the difference in OHCA survival.

CONCLUSIONS

Our survey highlighted a heterogeneity in AED legislation, AED mapping systems and AED use in Europe, which was reflected in different AED use and survival.

Accessibility of automatic external defibrillators and survival rate of people with out-of-hospital cardiac arrest: A systematic review of real-world studies

OBJECTIVE

To evaluate the relationship between the accessibility of automatic external defibrillators (AEDs) and the survival rate of patients who have out-of-hospital cardiac arrest (OHCA).

METHODS

The systematic review was conducted according to the Cochrane Handbook of Systematic Reviews. We searched the Chinese and English literature databases from 2009 to 2019. Study selection and data collection were conducted by three reviewers. One-month survival rates of OHCA with different AEDs accessibility were estimated using meta-analysis.

RESULTS

Overall 16 studies with 55,537 participants were included. The overall one-month survival rate for OHCA was 27.4%. The one-month survival rate was 35.2% for people receiving AEDs within 5 min, 36.6% between 5 min to 10 min, and 28.4% for longer than 10 min. By distance between the location of the AEDs and the location of the cardiac arrest, the one-month survival rate was 37.1% for those ≤100 m, 22.0% for 100 m-200 m, and 12.8% for >200 m, respectively. The one-month survival rate was 39.3% in schools, sports venues and airports compared with 23.5% in other sites. The number of AEDs allocation was positively correlated, while the time and distance were negatively correlated with the one-month survival rate adjusted for other factors, but they were all non-significant correlations.

CONCLUSION

The improvement of accessibility of AEDs may increase the survival rate of OHCA and the survival rate may be higher in playgrounds, airports, and schools equipped with AEDs. However, the strength of evidence was limited by the considerably heterogeneity of included studies. Verification of these findings in further studies is warranted.

Automated external defibrillators delivered by drones to patients with suspected out-of-hospital cardiac arrest

AIMS 

Early defibrillation is critical for the chance of survival in out-of-hospital cardiac arrest (OHCA). Drones, used to deliver automated external defibrillators (AEDs), may shorten time to defibrillation, but this has never been evaluated in real-life emergencies. The aim of this study was to investigate the feasibility of AED delivery by drones in real-life cases of OHCA.

METHODS AND RESULTS 

In this prospective clinical trial, three AED-equipped drones were placed within controlled airspace in Sweden, covering approximately 80 000 inhabitants (125 km2). Drones were integrated in the emergency medical services for automated deployment in beyond-visual-line-of-sight flights: (i) test flights from 1 June to 30 September 2020 and (ii) consecutive real-life suspected OHCAs. Primary outcome was the proportion of successful AED deliveries when drones were dispatched in cases of suspected OHCA. Among secondary outcomes was the proportion of cases where AED drones arrived prior to ambulance and time benefit vs. ambulance. Totally, 14 cases were eligible for dispatch during the study period in which AED drones took off in 12 alerts to suspected OHCA, with a median distance to location of 3.1 km [interquartile range (IQR) 2.8-3.4). AED delivery was feasible within 9 m (IQR 7.5-10.5) from the location and successful in 11 alerts (92%). AED drones arrived prior to ambulances in 64%, with a median time benefit of 01:52 min (IQR 01:35-04:54) when drone arrived first. In an additional 61 test flights, the AED delivery success rate was 90% (55/61).

CONCLUSION 

In this pilot study, we have shown that AEDs can be carried by drones to real-life cases of OHCA with a successful AED delivery rate of 92%. There was a time benefit as compared to emergency medical services in cases where the drone arrived first. However, further improvements are needed to increase dispatch rate and time benefits.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT04415398.

Implications for cardiac arrest coverage using straight-line versus route distance to nearest automated external defibrillator

AIM

Quantifying the ratio describing the difference between "true route" and "straight-line" distances from out-of-hospital cardiac arrests (OHCAs) to the closest accessible automated external defibrillator (AED) can help correct likely overestimations in AED coverage. Furthermore, we aimed to examine to what extent the closest AED based on true route distance differed from the closest AED using "straight-line".

METHODS

OHCAs (1994-2016) and AEDs (2016) in Copenhagen, Denmark and in Toronto, Canada (2007-2015 and 2015, respectively) were identified. Three distances were calculated between OHCA and target AED: 1) the straight-line distance ("straight-line") to the closest AED, 2) the corresponding true route distance to the same AED ("true route"), and 3) the closest AED based only on true route distance ("shortest true route"). The ratio between "true route" and "straight-line" distance was calculated and differences in AED coverage (an OHCA ≤ 100 m of an accessible AED) were examined.

RESULTS

The "straight-line" AED coverage of 100 m was 24.2% (n = 2008/8295) in Copenhagen and 6.9% (n = 964/13916) in Toronto. The corresponding "true route" distance reduced coverage to 9.5% (n = 786) and 3.8% (n = 529), respectively. The median ratio between "true route" and "straight-line" distance was 1.6 in Copenhagen and 1.4 in Toronto. In 26.1% (n = 2167) and 22.9% (n = 3181) of all Copenhagen and Toronto OHCAs respectively, the closest AED in "shortest true route" was different than the closest AED initially found by "straight-line".

CONCLUSIONS

Straight-line distance is not an accurate measure of distance and overestimates the actual AED coverage compared to a more realistic true route distance by a factor 1.4-1.6.

Immediate Bystander Cardiopulmonary Resuscitation to Sudden Cardiac Arrest During Sports is Associated with Improved Survival-a Video Analysis

Background

Sudden cardiac arrest (SCA) during sports can be the first symptom of yet undetected cardiovascular conditions. Immediate chest compressions and early defibrillation offer SCA victims the best chance of survival, which requires prompt bystander cardiopulmonary resuscitation (CPR).

Aims

To determine the effect of rapid bystander CPR to SCA during sports by searching for and analyzing videos of these SCA/SCD events from the internet.

Methods

We searched images.google.com, video.google.com, and YouTube.com, and included any camera-witnessed non-traumatic SCA during sports. The rapidity of starting bystander chest compressions and defibrillation was classified as < 3, 3–5, or > 5 min.

Results

We identified and included 29 victims of average age 27.6 ± 8.5 years. Twenty-eight were males, 23 performed at an elite level, and 18 participated in soccer. Bystander CPR < 3 min (7/29) or 3–5 min (1/29) and defibrillation < 3 min was associated with 100% survival. Not performing chest compressions and defibrillation was associated with death (14/29), and > 5 min delay of intervention with worse outcome (death 4/29, severe neurologic dysfunction 1/29).

Conclusions

Analysis of internet videos showed that immediate bystander CPR to non-traumatic SCA during sports was associated with improved survival. This suggests that immediate chest compressions and early defibrillation are crucially important in SCA during sport, as they are in other settings. Optimal use of both will most likely result in survival. Most videos showing recent events did not show an improvement in the proportion of athletes who received early resuscitation, suggesting that the problem of cardiac arrest during sports activity is poorly recognized.

Comparing audio- and video-delivered instructions in dispatcher-assisted cardiopulmonary resuscitation with drone-delivered automatic external defibrillator: a mixed methods simulation study

This study compared first responders' cardiopulmonary resuscitation (CPR) performance when a dispatcher provides audio instructions only and when both audio and video instructions are given. In the simulation, an automatic external defibrillator (AED) was delivered via drone in response to a cardiac arrest occurring outside a hospital setting. Participants' qualitative experiences were also explored.An exploratory sequential mixed methods design was used. AEDs were delivered to college students via drone with one group receiving both audio and video instructions and the other receiving audio-only instruction, and differences in CPR performance and accuracy were compared. After completion, focus group interview data were collected and analyzed. Video-based instruction was found to be more effective in the number of chest compressions (p < 0.01), chest compression rate (p < 0.01), and chest compression interruptions (p < 0.01). The accuracy of the video group for the chest compression region was high (p = 0.05). Participants' experiences were divided into three categories: "unfamiliar but beneficial experience," "met helper during a desperate and embarrassing situation," and "diverse views on drone use." Our results lay the groundwork for a development plan for providing emergency medical services using drones, as well as the preparation of guidelines for dispatchers on the provision of video instructions.

Public awareness and willingness to use automated external defibrillators in a metropolitan city

Objective

Early defibrillation is crucial for the survival of patients with out-of-hospital cardiac arrest. This study aimed to examine the trends and associated factors regarding public awareness and willingness to use automated external defibrillators (AEDs) through citywide surveys.

Methods

Three-round surveys were conducted in February 2012 (n=1,000), December 2016 (n=1,141), and December 2018 (n=1,001) among citizens in Daegu, South Korea, who were aged ≥19 years. The subjects were selected through a three-stage quota sampling. Awareness and willingness to use an AED were assessed in the three groups. The primary outcome was willingness to use AEDs.

Results

Of 3,142 respondents, 3,069 were eligible for analysis. The proportion of respondents who knew how to use AEDs increased from 4.7% in 2012 to 20.8% in 2018. Of the respondents in 2012, 2016, and 2018, 39.7%, 50.0%, and 43.2%, respectively, were willing to use an AED. Factors associated with willingness to use AEDs were male sex (adjusted odds ratio [AOR], 1.39; 95% confidence interval [CI], 1.10–1.75), cardiopulmonary resuscitation training experience in the previous 2 years (AOR, 1.80; 95% CI, 1.43–2.28), recognition of the Good Samaritan law (AOR, 1.45; 95% CI, 1.13–1.86), and awareness of how to use an AED (AOR, 4.40; 95% CI, 3.26–5.93).

Conclusion

To increase willingness to use AEDs, education in AED use and the Good Samaritan law, along with re-education to maintain knowledge of AED use, should be considered.

Assessment of Canadian Public Automated External Defibrillator Registries

BACKGROUND

Public automated external defibrillator (AED) registries aim to increase layperson defibrillation for victims of out-of-hospital cardiac arrest. This study aims to characterize Canadian AED registries and the process by which these databases are updated and used.

METHODS

A survey was administered to representatives from each eligible AED registry. Collected data included information on registry management, AED validation process, linkage to emergency medical dispatch (EMD), and number of AEDs per registry. Three unregistered AEDs in each region were then located and registered into their respective registry. The primary endpoint was the proportion of AEDs that became visible in the registry within 1 month.

RESULTS

Of the 9 Canadian provinces that have registries, 7 are provincial, whereas 2 contain smaller independent registries. The survey was completed by 90% of contacted registries. The number of AEDs per registry ranged from 21 to 443 per 100,000 persons. Six registries are managed by a provincial government, 6 use a standardized validation process, and 8 are linked to EMD. Of the 21 AEDs registered by our study personnel in 7/10 registries, 9 (43%) were made available to the public within 1 month of registration. Only 1 registry employed an AED validation process that included direct contact with AED managers.

CONCLUSIONS

Canadian public AED registries demonstrate significant differences in their governance and administrative processes. A majority of registries are integrated with EMD for out-of-hospital cardiac arrest, but not all registries use a standardized validation process to ensure accuracy of AED information submitted by the public.

Machine learning can support dispatchers to better and faster recognize out-of-hospital cardiac arrest during emergency calls: A retrospective study

AIM

Fast recognition of out-of-hospital cardiac arrest (OHCA) by dispatchers might increase survival. The aim of this observational study of emergency calls was to (1) examine whether a machine learning framework (ML) can increase the proportion of calls recognizing OHCA within the first minute compared with dispatchers, (2) present the performance of ML with different false positive rate (FPR) settings, (3) examine call characteristics influencing OHCA recognition.

METHODS

ML can be configured with different FPR settings, i.e., more or less inclined to suspect an OHCA depending on the predefined setting. ML OHCA recognition within the first minute is evaluated with a 1.5 FPR as the primary endpoint, and other FPR settings as secondary endpoints. ML was exposed to a random sample of emergency calls from 2018. Voice logs were manually audited to evaluate dispatchers time to recognition.

RESULTS

Of 851 OHCA calls, the ML recognized 36% (n = 305) within 1 min compared with 25% (n = 213) by dispatchers. The recognition rate at any time during the call was 86% for ML and 84% for dispatchers, with a median time to recognition of 72 versus 94 s. OHCA recognized by both ML and dispatcher showed a 28 s mean difference in favour of ML (P < 0.001). ML with higher FPR settings reduced recognition times.

CONCLUSION

ML recognized a higher proportion of OHCA within the first minute compared with dispatchers and has the potential to be a supportive tool during emergency calls. The optimal FPR settings need to be evaluated in a prospective study.

Characteristics and outcome after out-of-hospital cardiac arrest with the emphasis on workplaces: an observational study from the Swedish Registry of Cardiopulmonary Resuscitation

Background

Characteristics and outcome in out-of-hospital cardiac arrest (OHCA) occurring at workplaces is sparsely studied.

Aim

To describe (1) the characteristics and 30-day survival of OHCAs occurring at workplaces in comparison to OHCAs at other places and (2) factors associated with survival after OHCAs at workplaces.

Methods

Data on OHCAs were obtained from the Swedish Registry of Cardiopulmonary Resuscitation from 1 January 2008 to 31 December 2018. Characteristics and factors associated with survival were analysed with emphasis on the location of OHCAs.

Results

Among 47,685 OHCAs, 529 cases (1%) occurred at workplaces. Overall, in the fully adjusted model, all locations of OHCA, with the exception of crowded public places, displayed significantly lower probability of survival than workplaces. Exhibiting a shockable rhythm was the strongest predictor of survival among patients with OHCAs at workplaces; odds ratio (95% CI) 5.80 (2.92-12.31). Odds ratio for survival for women was 2.08 (95% CI 1.07-4.03), compared with men. At workplaces other than private offices, odds ratio for survival was 0.41 (95% CI 0.16-0.95) for cases who did not receive bystander CPR, as compared to those who did receive CPR. Among patients who were found in a shockable rhythm were 23% defibrillated before arrival of ambulance, which was more frequent than in any other location.

Conclusion

Out-of-hospital cardiac arrest occurring at workplaces and crowded public places display the highest probability of survival, as compared with other places outside hospital. An initial shockable cardiac rhythm was the strongest predictor of survival for OHCA at workplaces.

Awareness of Secondary School Students regarding Basic Life Support in Abha City, Southern Saudi Arabia: A Cross-Sectional Survey

BACKGROUND

Basic life support (BLS) is a level of medical care that is used for individuals with life-threatening illnesses or injuries until they can be given full medical care at a hospital. It can be provided by trained medical personnel, including emergency medical technicians and paramedics, and by qualified bystanders. Vital areas of adult BLS include immediate identification of sudden cardiac arrest and activation of the emergency response system, early performance of high-quality cardiopulmonary resuscitation (CPR), and rapid defibrillation, when appropriate.

AIM

To assess the awareness of secondary school students regarding BLS in Abha City, Saudi Arabia. Methodology. A descriptive cross-sectional survey was conducted targeting all accessible secondary school students in Abha City during the academic years 2018-2019. After explaining the objectives and importance of the research topic, all students in the three grades were invited to complete the study questionnaire. The questionnaire was developed by the researchers after reviewing the literature for related topics and consulting an expert for any additions or modifications.

RESULTS

The study included 761 students with ages ranging from 15 to 20 years and a mean age of 17 ± 1 years old. Male students accounted for 53.6% of the participants, and 96.7% of the participants were Saudi. Exactly 31% of the students had had a BLS training course, among which 79.2% had had training that lasted for only one day. Regarding awareness, 65% of the students had heard about BLS, and 44% knew about CPR. Exactly 52% of the students indicated that they should call the ER if there was a case with fainting. A total of 45.3% of the students reported that airway checking was the first step in CPR, and 16.7% reported that the chest compression to oral breathing ratio should be 30 to 2. Conclusions and Recommendations. In conclusion, the study revealed that poor awareness regarding BLS was present among the students. The researchers concluded that less than one-third of the students had BLS training. BLS should be taught, theoretically and practically (with simulations), to middle and high school students as BLS involves relatively simple concepts and methods.

Quality of dispatcher-assisted vs. automated external defibrillator-guided cardiopulmonary resuscitation: a randomised simulation trial

BACKGROUND

Quality of hands-only cardiopulmonary resuscitation (CPR) is an important determinant of resuscitation outcome for cardiac arrest patients cared for by lay rescuers. We designed a simulation trial to assess and compare the quality of CPR among untrained lay people under two different scenarios: automated external defibrillator (AED)-guided and dispatcher-assisted CPR.

PATIENTS AND METHODS

A simulation study was performed involving 42 volunteers selected by non-probabilistic sampling. Participants were randomized into two CPR simulation scenarios with a manikin: (A) AED-guided CPR and (T) dispatcher-assisted CPR. The quality of CPR was evaluated by metric monitoring of the chest compressions and timing of actions. Content analysis of the telephone instructions was performed by two independent researchers using a checklist.

RESULTS

CPR was started in 20 of the 21 cases in scenario A and in all cases in scenario T. In total, 12 053 chest compressions were applied, 57.6% corresponding to scenario A. The proportion of compressions that were of an adequate depth was low in both cases, 15.3% in scenario A vs. 31.7% in scenario T (P < 0.001), while complete chest recoil was allowed in 66 and 72% (P < 0.001) of compressions, respectively. The AED advised to shock 91 times, and shocks were delivered in all cases.

CONCLUSIONS

Although guided CPR helps untrained people to initiate resuscitation manoeuvres, the quality of CPR was poor in both groups. Telephone guidance improved the proportion of compressions that achieved adequate chest compression and recoil but did not optimise the compression rate.

Cost-effectiveness of a novel smartphone application to mobilize first responders after witnessed OHCA in Belgium

Background

EVapp (Emergency Volunteer Application) is a Belgian smartphone application that mobilizes volunteers to perform cardiopulmonary resuscitation (CPR) and defibrillation with publicly available automatic external defibrillators (AED) after an emergency call for suspected out of hospital cardiac arrest (OHCA). The aim is to bridge the time before the arrival of the emergency services.

Methods

An accessible model was developed, using literature data, to simulate survival and cost-effectiveness of nation-wide EVapp implementation. Initial validation was performed using field data from a first pilot study of EVapp implementation in a city in Flanders, covering 2.5 years of implementation.

Results

Simulation of nation-wide EVapp implementation resulted in an additional yearly 910 QALY gained over the current baseline case scenario (worst case 632; best case 3204). The cost per QALY associated with EVapp implementation was comparable to the baseline scenario, i.e., 17 vs 18 k€ QALY⁻¹.

Conclusions

EVapp implementation was associated with a positive balance on amount of QALY gained and cost of QALY. This was a consequence of both the lower healthcare costs for patients with good neurological outcome and the more efficient use of yet available resources, which did not outweigh the costs of operation.

Improving bystander defibrillation in out-of-hospital cardiac arrests at home

Aims:

Most out-of-hospital cardiac arrests occur at home with dismal bystander defibrillation rates. We investigated automated external defibrillator coverage of home arrests, and the proportion potentially reachable with an automated external defibrillator before emergency medical service arrival according to different bystander activation strategies.

Methods and results:

Cardiac arrests in homes (private/nursing/senior homes) in Copenhagen, Denmark (2008–2016) and registered automated external defibrillators (2007–2016), were identified. Automated external defibrillator coverage (distance from arrest to automated external defibrillator) and accessibility at the time of arrest were examined according to route distance to nearest automated external defibrillator and emergency medical service response time. The proportion of arrests reachable with an automated external defibrillator by bystander was calculated using two-way (from patient to automated external defibrillator and back) and one-way (from automated external defibrillator to patient) potential activation strategies. Of 1879 home arrests, automated external defibrillator coverage ≤100 m was low (6.3%) and a two-way bystander could potentially only retrieve an accessible automated external defibrillator before emergency medical service in 31.1% (n=37) of cases. If a bystander only needed to travel one-way to bring an automated external defibrillator (≤100 m, ≤250 m and ≤500 m), 45.4% (n=54/119), 37.1% (n=196/529) and 29.8% (n=350/1174) could potentially be reached before the emergency medical service based on current automated external defibrillator accessibility.

Conclusions:

Few home arrests were reachable with an automated external defibrillator before emergency medical service if bystanders needed to travel from patient to automated external defibrillator and back. However, nearly one-third of arrests ≤500 m of an automated external defibrillator could be reached before emergency medical service arrival if the bystander only needed to travel one-way from the automated external defibrillator to the patient.

Adult Basic Life Support: International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 20 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 3 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Part 7: Systems of Care: 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

Survival after cardiac arrest requires an integrated system of people, training, equipment, and organizations working together to achieve a common goal. Part 7 of the 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care focuses on systems of care, with an emphasis on elements that are relevant to a broad range of resuscitation situations. Previous systems of care guidelines have identified a Chain of Survival, beginning with prevention and early identification of cardiac arrest and proceeding through resuscitation to post-cardiac arrest care. This concept is reinforced by the addition of recovery as an important stage in cardiac arrest survival. Debriefing and other quality improvement strategies were previously mentioned and are now emphasized. Specific to out-of-hospital cardiac arrest, this Part contains recommendations about community initiatives to promote cardiac arrest recognition, cardiopulmonary resuscitation, public access defibrillation, mobile phone technologies to summon first responders, and an enhanced role for emergency telecommunicators. Germane to in-hospital cardiac arrest are recommendations about the recognition and stabilization of hospital patients at risk for developing cardiac arrest. This Part also includes recommendations about clinical debriefing, transport to specialized cardiac arrest centers, organ donation, and performance measurement across the continuum of resuscitation situations.

Adult Basic Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This2020 International Consensus on Cardiopulmonary Resuscitation(CPR)and Emergency Cardiovascular Care Science With Treatment Recommendationson basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

The automated external defibrillator, an underused simple life-saving device: a review of the literature. A joint document from the Italian Resuscitation Council (IRC) and Associazione Italiana di Aritmologia e Cardiostimolazione (AIAC)

: The role of early defibrillation has been well established as a pivotal ring of the chain of survival since the nineties. In the following years, the scientific evidences about the beneficial role of early defibrillation have grown, and most of all, it has been demonstrated that the main determinant of survival is the time of defibrillation more than the type of rescuer. Early lay defibrillation was shown to be more effective than delayed defibrillation by healthcare providers. Moreover, because of the ease of use of automated external defibrillators (AEDs), it has been shown that also untrained lay rescuers can safely use an AED leading the guidelines to encourage early defibrillation by untrained lay bystanders. Although strong evidence has demonstrated that an increase in AED use leads to an increase in out-of-hospital cardiac arrest (OHCA) survival, the rate of defibrillation by laypeople is quite variable worldwide and very low in some realities. Our review of the literature about lay defibrillation highlights that the AED is a life-saving device as simple and well tolerated as underused.

Real-world insight into public access defibrillator use over five years

BACKGROUND

Public access defibrillators (PADs) represent unique life-saving medical devices as they may be used by untrained lay rescuers. Collecting representative clinical data on these devices can be challenging. Here, we present results from a retrospective observational cohort study, describing real-world PAD utilisation over a 5-year period.

METHODS

Data were collected between October 2012 and October 2017. Responders voluntarily submitted electronic data downloaded from HeartSine PADs, and patient demographics and other details using a case report form in exchange for a replacement battery and electrode pack.

RESULTS

Data were collected for 977 patients (692 males, 70.8%; 255 females, 26.1%; 30 unknown, 3.1%). The mean age (SD) was 59 (18) years (range <1 year to 101 years). PAD usage occurred most commonly in homes (n=328, 33.6%), followed by public places (n=307, 31.4%) and medical facilities (n=128, 13.1%). Location was unknown in 40 (4.09%) events. Shocks were delivered to 354 patients. First shock success was 312 of 350 patients where it could be determined (89.1%, 95% CI 85.4% to 92.2%). Patients with reported response times ≤5 min were more likely to survive to hospital admission (89/296 (30.1%) vs 40/250 (16.0%), p<0.001). Response time was unknown for 431 events.

CONCLUSION

This is the first study to report global PAD usage in voluntarily submitted, unselected real-world cases and demonstrates the real-world effectiveness of PADs, as confirmed by first shock success.

AED and text message responders density in residential areas for rapid response in out-of-hospital cardiac arrest

BACKGROUND

For out-of-hospital cardiac arrest (OHCA) in residential areas, a dispatcher driven alert-system using text messages (TM-system) directing local rescuers (TM-responders) to OHCA patients was implemented and the desired density of automated external defibrillators (AEDs) or TM-responders investigated.

METHODS

We included OHCA cases with the TM-system activated in residential areas between 2010-2017. For each case, densities/km² of activated AEDs and TM-responders within a 1000 m circle were calculated. Time intervals between 112-call and first defibrillation were calculated.

RESULTS

In total, 813 patients (45%) had a shockable initial rhythm. In 17% a TM-system AED delivered the first shock. With increasing AED density, the median time to shock decreased from 10:59 to 08:17 min. (p < 0.001) and shocks <6 min increased from 6% to 12% (p = 0.024). Increasing density of TM-responders was associated with a decrease in median time to shock from 10:59 to 08:20 min. (p < 0.001) and increase of shocks <6 min from 6% to 13% (p = 0.005). Increasing density of AEDs and TM-responders resulted in a decline of ambulance first defibrillation by 19% (p = 0.016) and 22% (p = 0.001), respectively. First responder AED defibrillation did not change significantly. Densities of >2 AEDs/km² did not result in further decrease of time to first shock but >10 TM-responders/km² resulted in more defibrillations <6 min.

CONCLUSION

With increasing AED and TM-responder density within a TM-system, time to defibrillation in residential areas decreased. AED and TM-responders only competed with ambulances, not with first responders. The recommended density of AEDs and TM-responders for earliest defibrillation is 2 AEDs/km² and >10 TM-responders/km².

Can you get there from here? An analysis of walkability among PulsePoint CPR alert dispatches

BACKGROUND

Bystander CPR before the arrival of EMS is a major factor in out of hospital cardiac arrest (OHCA) survival. To recruit trained bystanders, mobile phone-based alert systems have been developed, but their limitations are not well understood.

OBJECTIVE

We investigated the effects of landscape features on the capabilities of the PulsePoint CPR dispatch platform in Allegheny County, Pennsylvania. We hypothesized that landscape features would reduce walkable area within dispatch zones and that larger alert radii could mitigate these effects.

METHODS

CPR alert location data were obtained from the Allegheny County 911 PulsePoint deployment from July 2016-2019 (n = 1100). PulsePoint, a smartphone-based citizen CPR dispatch platform, alerts volunteers to public OHCAs within 400 m. Digital maps of alerts were generated for walkability analysis using the image Labeler MATLAB polygon tool. Unwalkable areas were labeled, classified into five categories, and quantified.

RESULTS

Of the 1100 events analyzed, encompassing 212 mi², 357 (32.45%) had no impediments to walkability. Within a 400 m radius of partially impeded events, the median proportion of obstructed area was 0.2250 (Min: 0.0005, Max: 0.8338, IQR: 0.3004, S_x: 0.1923). When the alert radius was expanded to 468 m, the median increased to 0.2336 (Min: 0.0016, Max: 0.8597, IQR: 0.3064, S_x: 0.1950). The percentages of total unwalkable area by each category were: terrain (54.286%), water (24.674%), road w/o crosswalk (11.3197%), railroad (7.4100%), private property (2.3102%).

CONCLUSIONS

In this region, most PulsePoint alerts had unwalkable areas, mostly from terrain and water. Contrary to our initial hypotheses, moderately increasing dispatch radius did not improve walkability.

A nationwide overview of 1-year mortality in cardiac arrest patients admitted to intensive care units in the Netherlands between 2010 and 2016

AIM

Worldwide, cardiac arrest (CA) remains a major cause of death. Most post-CA patients are admitted to the intensive care unit (ICU). The aim of this study is to describe mortality rates and possible changes in mortality rates in patients with CA admitted to the ICU in the Netherlands between 2010 and 2016.

METHODS

In this study, we included all adult CA patients registered in the National Intensive Care Evaluation (NICE) registry who were admitted to ICUs in the Netherlands between 2010 and 2016. The primary outcome was 1-year mortality which was analysed by Cox regression. The secondary outcomes were ICU mortality and hospital mortality. Hospital mortality was analysed by binary logistic regression analysis. Patients were stratified by whether they experienced in-hospital cardiac arrest (IHCA) or out-of-hospital cardiac arrest (OHCA). Finally, the outcome over calendar time was assessed for both groups.

RESULTS

We included 26,056 CA patients: 10,618 (40.8%) IHCA patients and 14,482 (55.6%) OHCA patients. The 1-year mortality rate was 57.5%: 59% for IHCA and 56.4% for OHCA, p < 0.01. This mortality rate remained stable between 2010 and 2016 for IHCA (p = 0.31) and declined for OHCA patients (p = 0.01). The hospital mortality rate was 50.3%: 50.5% for IHCA and 50.2% for OHCA, p = 0.66. This mortality rate remained stable between 2010-2016 for IHCA (p = 0.21) and decreased for OHCA patients (p < 0.01). An additional analysis with calendar year as a continuous variable showed a mortality decline of 1.56% per calendar year for 1-year mortality.

CONCLUSION

This nationwide registry cohort study reported a 57.5% 1-year mortality rate for CA patients admitted to the ICU between 2010 and 2016. We reported a decline in 1-year mortality for OHCA patients in these years.

Sudden Cardiac Death in Famous Athletes, Lessons Learned, Heterogeneity in Expert Recommendations and Pitfalls of Contemporary Screening Strategies

Sudden cardiac death (SCD) in competitive athletes, though relatively uncommon, invariably leads to controversy. Specific limitations of an extensive screening process include lack of robust evidence to support prevention of SCD, poor cost-effectiveness and uncertain downstream implications of a positive screening test. An emerging body of evidence points to enhanced neurologically intact survival to hospital discharge when automated external defibrillators (AEDs) are used in a timely manner following sudden cardiac arrest (SCA). A viable alternative to an expansive screening process could be a robust secondary prevention system comprising of improvements in AED availability, stringent enforcement of CPR training in athletes and trainers to provide timely and effective resuscitation to reduce death following SCA. This strategy could widen the window to diagnose and treat the underlying etiology and prevent recurrence of SCA while also offering financial feasibility. Restricting athletes from competitive sports is a difficult decision for physicians owing to a lack of well-defined cutoffs for acceptable and prohibitive risk from pathology predisposing to SCD, especially in the absence of a protective medico-legal framework. In this review, we highlight a few cases that generated intense scrutiny by the public, media and medical professionals about the efficacy, feasibility and pitfalls of the existing screening process to diagnose cardiovascular pathology predisposing to SCD. Furthermore, contrasting approaches to screening, diagnosis and downstream workup protocols between the European Society of Cardiology and the American Heart Association are analyzed.

Heart defibrillation: relationship between pacing threshold and defibrillation probability

BACKGROUND

Considering the clinical importance of the ventricular fibrillation and that the most used therapy to reverse it has a critical side effect on the cardiac tissue, it is desirable to optimize defibrillation parameters to increase its efficiency. In this study, we investigated the influence of stimuli duration on the relationship between pacing threshold and defibrillation probability.

RESULTS

We found out that 0.5-ms-long pulses had a lower ratio of defibrillation probability to the pacing threshold, although the higher the pulse duration the lower is the electric field intensity required to defibrillate the hearts.

CONCLUSION

The appropriate choice of defibrillatory shock parameters is able to increase the efficiency of the defibrillation improving the survival chances after the occurrence of a severe arrhythmia. The relationship between pulse duration and the probability of reversal of fibrillation shows that this parameter cannot be underestimated in defibrillator design since different pulse durations have different levels of safety.

The effect of automatic external defibrillator with a real-time feedback on quality of bystander cardiopulmonary resuscitation: A before-and-after simulation study

High-quality bystander cardiopulmonary resuscitation (CPR) and early defibrillation in the community are important for survival in out-of hospital-cardiac-arrest, but maintaining the quality of CPR in bystanders is difficult. We aimed to determine the effect of an automated external defibrillator (AED) with real-time feedback on the quality of bystander CPR in a community setting. A before-and-after simulation study was designed. Trainees of basic life support education were recruited for the simulation experiment. Each team consisted of two bystanders with different roles (initial witness and CPR supporter). 82 teams performed simulation scenarios with the real-time feedback function of AED disabled initially, and then repeated it with feedback function enabled. Quality measures of chest compression depth and no-flow fraction were compared between each of the two simulation scenarios. CPR quality data from 82 teams were analysed. The mean percentage of chest compressions with adequate depth was significantly higher in simulations with real-time feedback (78.1% vs. 89.3%, p < 0.01). Similarly, no-flow fractions were lower in simulation scenarios with real-time feedback (32.0% vs. 30.3% p = 0.05). In a subgroup with the lowest percentage of adequate depth performance in the initial simulation without real-time feedback, a mean increase of 47.7% (95% CI 31.3-64.0) in the fraction of chest compressions with adequate depth was seen with real-time feedback. Use of an AED with real-time feedback improves the quality of bystander CPR in a simulated community setting. The positive effect of real-time feedback is greatest among people with a low level of CPR skill.

Final-year medical students' knowledge of cardiac arrest and CPR: We must do more!

BACKGROUND

Students are an important part of the community response to an out-of-hospital cardiac arrest (OHCA). If even schoolchildren now know cardio-pulmonary resuscitation (CPR), even more the reason a young doctor should know how to treat an OHCA. The aim of our study was to assess medical students' knowledge of CPR and OHCA throughout Europe.

METHODS

An online survey was given to final-year students by the Medical Student Associations of different countries.

RESULTS

1012 medical students from 99 different universities and 14 different countries completed the questionnaire. A total of 82.2% attended a BLS or BLS/AED course, provided by the University in only 69.7% of cases. In 84.3% it was a mandatory part of their degree. A total of 78.6% felt able to rescue a person in OHCA. Only 49.3% knew that 'unresponsiveness' and 'absence of normal breathing' are sufficient for lay people to identify an OHCA, and less than half of those interviewed knew the incidence of OHCA in Europe and the decrease in chance of survival if CPR is not performed. The correct compression:ventilation ratio was known by 90.2%, the correct compression depth by 69.7%, whilst only 57.8% knew the right compression rate. In total, 69.7% knew that an AED must be used immediately when available, and only 57.2% recognized the AED symbol.

CONCLUSIONS

Medical students' knowledge of cardiac arrest and CPR needs to be improved throughout Europe and we believe that BLS/AED training should be mandatory in all European Universities.

Bystander Defibrillation for Out-of-Hospital Cardiac Arrest in Public vs Residential Locations

Importance

Bystander-delivered defibrillation (hereinafter referred to as bystander defibrillation) of patients with out-of-hospital cardiac arrests (OHCAs) remains limited despite the widespread dissemination of automated external defibrillators (AEDs).

Objective

To examine calendar changes in bystander defibrillation and subsequent survival according to a public or a residential location of the cardiac arrest after nationwide initiatives in Denmark to facilitate bystander-mediated resuscitative efforts, including bystander defibrillation.

Design, Setting, and Participants

This nationwide study identified 18 688 patients in Denmark with first-time OHCA from June 1, 2001, to December 31, 2012, using the Danish Cardiac Arrest Registry. Patients had a presumed cardiac cause of arrest that was not witnessed by emergency medical services personnel. Data were analyzed from April 1, 2015, to December 10, 2016.

Exposures

Nationwide initiatives to facilitate bystander resuscitative efforts, including bystander defibrillation, consisted of resuscitation training of Danish citizens, dissemination of on-site AEDs, foundation of an AED registry linked to emergency medical dispatch centers, and dispatcher-assisted guidance of bystander resuscitation efforts.

Main Outcomes and Measures

The proportion of patients who received bystander defibrillation according to the location of the cardiac arrest and their subsequent 30-day survival.

Results

Of the 18 688 patients with OHCAs (67.8% men and 32.2% women; median [interquartile range] age, 72 [62-80] years), 4783 (25.6%) had a cardiac arrest in a public location and 13 905 (74.4%) in a residential location. The number of registered AEDs increased from 141 in 2007 to 7800 in 2012. The distribution of AED location was consistently skewed in favor of public locations. Bystander defibrillation increased in public locations from 3 of 245 (1.2%; 95% CI, 0.4%-3.5%) in 2001 to 78 of 510 (15.3%; 95% CI, 12.4%-18.7%) in 2012 (P < .001) but remained unchanged in residential locations from 7 of 542 (1.3%; 95% CI, 0.6%-2.6%) in 2001 to 21 of 1669 (1.3%; 95% CI, 0.8%-1.9%) in 2012 (P = .17). Thirty-day survival after bystander defibrillation increased in public locations from 8.3% (95% CI, 1.5%-35.4%) in 2001/2002 to 57.5% (95% CI, 48.6%-66.0%) in 2011/2012 (P < .001) in residential locations, from 0.0% (95% CI, 0.0%-19.4%) in 2001/2002 to 25.6% (95% CI, 14.6%-41.1%) in 2011/2012 (P < .001).

Conclusions and Relevance

Initiatives to facilitate bystander defibrillation were associated with a marked increase in bystander defibrillation in public locations, whereas bystander defibrillation remained limited in residential locations. Concomitantly, survival increased after bystander defibrillation in residential and public locations.

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.

Drone delivery of an automated external defibrillator - a mixed method simulation study of bystander experience

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) affects some 275,000 individuals in Europe each year. Time from collapse to defibrillation is essential for survival. As emergency medical services (EMS) response times in Sweden have increased, novel methods are needed to facilitate early treatment. Unmanned aerial vehicles (i.e. drones) have potential to deliver automated external defibrillators (AED). The aim of this simulation study was to explore bystanders' experience of a simulated OHCA-situation where a drone delivers an AED and how the situation is affected by having one or two bystanders onsite.

METHODS

This explorative simulation study used a mixed methodology describing bystanders' experiences of retrieving an AED delivered by a drone in simulated OHCA situations. Totally eight participants were divided in two groups of bystanders a) alone or b) in pairs and performed CPR on a manikin for 5 minutes after which an AED was delivered by a drone at 50 m from the location. Qualitative data from observations, interviews of participants and video recordings were analysed using content analysis alongside descriptive data on time delays during bystander interaction.

RESULTS

Three categories of bystander experiences emerged: 1) technique and preparedness, 2) support through conversation with the dispatcher, and 3) aid and decision-making. The main finding was that retrieval of an AED as delivered by a drone was experienced as safe and feasible for bystanders. None of the participants hesitated to retrieve the AED; instead they experienced it positive, helpful and felt relief upon AED-drone arrival and were able to retrieve and attach the AED to a manikin. Interacting with the AED-drone was perceived as less difficult than performing CPR or handling their own mobile phone during T-CPR. Single bystander simulation introduced a significant hands-off interval when retrieving the AED, a period lasting 94 s (range 75 s-110 s) with one participant compared to 0 s with two participants.

CONCLUSION

The study shows that it made good sense for bystanders to interact with a drone in this simulated suspected OHCA. Bystanders experienced delivery of AED as safe and feasible. This has potential implications, and further studies on bystanders' experiences in real cases of OHCA in which a drone delivers an AED are therefore necessary.

Self-learning training versus instructor-led training for basic life support: A cluster randomised trial

AIM

To compare the effectiveness of two basic life support (BLS) training interventions.

METHODS

This experimental trial enrolled 1301 lay people in BLS training. The participants were cluster randomised to either self-learning training or to traditional instructor-led training. Both groups used the Mini-Anne Kit (Laerdal Medical, Stavanger, Norway) and standardised film instructions. After training, the participants practical skills were measured on a Resusci Anne manikin and an AED trainer with the PC SkillReporting system (Laerdal Medical, Stavanger, Norway). The primary outcome was the total score from the modified Cardiff Test of basic life support with automated external defibrillation (19-70 points), six months after training. The secondary outcomes were total score directly after training and quality of individual variables, self-assessed knowledge, confidence and willingness to act, directly and six months after training.

RESULTS

For primary outcome six months after training there was no statistically significant difference (p = 0.44) between the total score for the self-learning group (n = 670; median 59, IQR 55-62) compared with the instructor-led group (n = 561; median 59, IQR 55-63). The instructor-led training resulted in a statistically significant higher total score (median 61 versus 59, p < 0.0001), self-assessed knowledge and willingness to act, directly after training (secondary outcomes) compared with the self-learning training.

CONCLUSIONS

There was no statistically significant difference in practical skills or willingness to act when comparing self-learning training with instructor-led training six months after training in BLS. However, directly after the intervention, practical skills were better when the training was led by an instructor.

Targeting relatives: Impact of a cardiac rehabilitation programme including basic life support training on their skills and attitudes

Background

Training families of patients at risk for sudden cardiac death in basic life support (BLS) has been recommended, but remains challenging. This research aimed to determine the impact of embedding resuscitation training for patients in a cardiac rehabilitation programme on relatives' BLS skill retention at six months.

Design

Intervention community study.

Methods

Relatives of patients suffering acute coronary syndrome or revascularization enrolled on an exercise-based cardiac rehabilitation programme were included. BLS skills of relatives linked to patients in a resuscitation-retraining programme (G-CPR) were compared with those of relatives of patients in a standard programme (G-Stan) at baseline, following brief instruction and six months after. Differences in skill performance and deterioration and self-perceived preparation between groups over time were assessed.

Results

Seventy-nine relatives were included and complete data from 66 (G-Stan=33, G-CPR=33) was analysed. Baseline BLS skills were equally poor, improved irregularly following brief instruction and decayed afterwards. G-CPR displayed six-month better performance and lessened skill deterioration over time compared with G-Stan, including enhanced compliance with the BLS sequence ( p = 0.006 for group*time interaction) and global resuscitation quality ( p = 0.007 for group*time interaction). Self-perceived preparation was higher in G-CPR ( p = 0.002).

Conclusions

Relatives of patients suffering acute coronary syndrome or revascularization enrolled on a cardiac rehabilitation programme showed poor BLS skills. A resuscitation-retraining cardiac rehabilitation programme resulted in relatives' higher BLS awareness, skill retention and confidence at six months compared with the standard programme. This may suggest a significant impact of this formula on the family setting and support the active role of patients to enhance health education in their environment.

Outcome of exercise-related out-of-hospital cardiac arrest is dependent on location: Sports arenas vs outside of arenas

Background

The chance of surviving an out-of-hospital cardiac arrest (OHCA) seems to be increased if the cardiac arrests occurs in relation to exercise. Hypothetically, an exercise-related OHCA at a sports arena would have an even better prognosis, because of an increased likelihood of bystander cardiopulmonary resuscitation (CPR) and higher availability of automated external defibrillators (AEDs). The purpose of the study was to compare survival rates between exercise-related OHCA at sports arenas versus outside of sports arenas.

Methods

Data from all treated exercise-related OHCA outside home reported to the Swedish Register of Cardiopulmonary Resuscitation (SRCR) from 2011 to 2014 in 10 counties of Sweden was analyzed (population 6 million). The registry has in those counties a coverage of almost 100% of all OHCAs.

Results

3714 cases of OHCA outside of home were found. Amongst them, 268(7%) were exercise-related and 164 (61.2%) of those occurred at sports arenas. The 30-day survival rate was higher for exercise-related OHCA at sports arenas compared to outside (55.7% vs 30.0%, p<0.0001). OHCA-victims at sports arenas were younger (mean age±SD 57.6±16.3 years compared to 60.9±17.0 years, p = 0.05), less likely female (4.3% vs 12.2%, p = 0.02) and had a higher frequency of shockable rhythm (73.0% vs 54.3%, p = 0.004). OHCAs at arenas were more often witnessed (83.9% vs 68.9%, p = 0.007), received bystander CPR to a higher extent (90.0% vs 56.8%, p<0.0001) and the AED-use before EMS-arrival was also higher in this group (29.8% vs 11.1%, p = 0.009).

Conclusion

The prognosis is markedly better for exercise-related OHCA occurring at sports arenas compared to outside. Victims of exercise-related OHCA at sports arenas are more likely to receive bystander CPR and to be connected to a public AED. These findings support an increased use of public AEDs and implementation of Medical Action Plans (MAP), to possibly increase survival of exercise-related OHCA even further.