Bystander Automated External Defibrillator Research Articles

Out-of-hospital cardiac arrest outcomes when law enforcement arrives before emergency medical services

BackgroundLaw enforcement (LE) professionals are often dispatched to out-of-hospital cardiac arrests (OHCA) to provide early cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) application with mixed evidence of a survival benefit. Our objective was to comprehensively evaluate LE care in OHCA. MethodsThis is a secondary analysis of adults with non-traumatic OHCA not witnessed by EMS and without bystander AED use from 2018-2021. Our primary outcome was survival with Cerebral Perfusion Category score ≤ 2 (functional survival). Our exposures included: LE On-scene Only (without providing care); LE CPR Only (without applying an AED); LE Ideal Care (ensuring CPR and AED application). Our control group had no LE arrival before EMS. We performed multivariable logistic regression analyses adjusting for confounders and stratified our analyses by patients with and without bystander CPR. ResultsThere were 2569 adult, non-traumatic OHCAs from 2018-2021 meeting inclusion criteria. There were no differences in the odds of functional survival for LE On-scene Only (adjusted odds ratio [95% CI]: 1.28 [0.47–3.45]), LE CPR Only (1.26 [0.80–1.99]), or LE Ideal Care (1.36 [0.79–2.33]). In patients without bystander CPR, LE Ideal Care had significantly higher odds of functional survival (2.01 [1.06–3.81]) compared to no LE on-scene, with no significant associations for LE On-scene Only or LE CPR Only. There were no significant differences by LE care in patients already receiving bystander CPR. ConclusionsLE arrival before EMS and ensuring both CPR and AED application is associated with significantly improved functional survival in OHCA patients not already receiving bystander CPR.

Abstract 337: Bystander Defibrillation in High Risk Neighborhoods

Background: Whether public health efforts successfully prioritize bystander automated external defibrillator (AED) application in areas with highest of hospital cardiac arrest (OHCA) burden is unknown. Methods: Within the Cardiac Arrest Registry to Enhance Survival, we identified all adult, public OHCAs linked to a census tract between 2013- 2021. We ranked all census tracts by annual public OHCA volume to ascertain relative burden, then assessed the association of census tract OHCA burden and bystander AED application rate (application prior to emergency personnel arrival), using a hierarchical modified poisson regression model, to account for clustering within tracts, and arrest characteristics. Results: Among 25,787 tracts with 90,898 public OHCAs, the mean (SD) age was 57.1 (16.0) years, with 70,900 (78.0%) male and 45,388 (49.9%) White victims. Overall, bystander AED application rates were low (10.9%). There was a modest association between neighborhood OHCA burden and bystander AED application rates (ρ=0.243). After adjustment, neighborhoods with the highest OHCA burden (>2/ year) had a higher relative risk of bystander AED application than those with lowest burden (<1/ every other year) (RR 2.07; 95% CI 1.95, 2.20, p<.0001). However, this was due to a small proportion of high performing communities, as 700/1145 (61.1%) of highest OHCA burden communities had a bystander AED application rate less than the overall mean, 10.9%. Conclusion: High OHCA burdened areas have increased odds of bystander AED application, however this is driven by a few high performing neighborhoods. Targeted, context informed strategies are necessary to improve application rates and survival for the majority of high-risk neighborhoods.

Abstract 18326: The Association of s Shockable Rhythm and Automated External Defibrillator Use With Outcomes in Infants With Out of Hospital Cardiac Arrest: A Study From the Cardiac Arrest Registry to Enhance Survival

Introduction: Defibrillation with an automated external defibrillator (AED) is critical in the chain of survival following a cardiac arrest caused by pulseless ventricular tachycardia and ventricular fibrillation. However, in 2022 the International Liaison Committee on Resuscitation could not make a recommendation for or against the use of AEDs in infants. Hypothesis: We aimed to describe the association of a shockable rhythm with outcomes in infants with out of hospital cardiac arrest (OHCA) and test the hypothesis that a shockable rhythm and AED use with defibrillation would be associated with improved neurologically favorable survival at hospital discharge by analyzing data from a large cardiac arrest registry in the United States Methods: We conducted an analysis of the Cardiac Arrest Registry to Enhance Survival database. Inclusion criteria were age < 1 year of age and non-traumatic OHCA from January 1, 2013 through December 31, 2021. The primary outcome was neurologically favorable survival defined as a Cerebral Performance Category Scale of 1 or 2. Results: A total of 10,108 infants with OHCA were evaluated of which 308 (3%) had a shockable rhythm and 9,800 (97%) had a non-shockable rhythm. Compared to infants with non-shockable rhythms infants with shockable rhythms were more likely to be white (37.7% white, 25.6% black, 7.5% Hispanic), have a witnessed arrest (44.5% vs. 16%), a non-home/public arrest (16.9% vs. 6.7%), and bystander AED application with defibrillation (19.4% vs. 0.18%) (p<0.05 for all). Neurologically favorable survival (19.2% shockable vs. 4.2% non-shockable was higher in arrests with a shockable rhythm compared to non-shockable arrests, p<0.001). AEDs were applied by bystanders in 1479 (14.5%) arrests and were associated with neurologically favorable survival (11% AED with defibrillation vs. 3.5% AED without defibrillation, p=0.002) Conclusions: Although infants infrequently had an OHCA with a shockable rhythm survival outcomes were superior in arrests with a shockable rhythm and in arrests where there was bystander AED use with defibrillation. These results emphasize the importance of AED use in infants with shockable rhythms following an OHCA.

Characteristics and Treatment Outcomes of Out-of-Hospital Cardiac Arrests Occurring in Public Places: A National Population-Based Observational Study.

Sudden cardiac arrest, particularly out-of-hospital cardiac arrest (OHCA), is a global public health concern. However, limited research exists on the epidemiology of OHCAs occurring in public places, trends and impact of bystander intervention, and influence of extraordinary circumstances. This study investigated the epidemiological factors, bystander characteristics, and outcomes of OHCAs that occurred in public places in South Korea from 2016 to 2021 and analyzed the impact of the coronavirus disease 2019 (COVID-19) pandemic. A retrospective analysis was conducted using an Out-of-Hospital Cardiac Arrest Surveillance database, including 33,206 cases of OHCA that occurred in public places. Cases with do-not-resuscitate orders or insufficient data were excluded. A steady increase in bystander-performed cardiopulmonary resuscitation over the years and a constant decrease in bystander automated external defibrillator (AED) use were observed. Survival-to-discharge rates for OHCAs remained relatively steady until a marginal decrease was observed during the pandemic (pandemic, 13.1%; pre-pandemic, 14.4%). Factors affecting survival included the presence of a shockable rhythm, witnessed arrest, cardiac arrest due to disease, use of bystander AED, and period relative to the COVID-19 pandemic. These findings emphasize the critical role of bystanders in outcomes of OHCAs and inform public health strategies on better management of OHCAs in public places.

Documented Use of Emergency Medical Dispatch Protocols is Associated with Improved Survival in Out of Hospital Cardiac Arrest

Objective There are over 300,000 out-of-hospital cardiac arrests (OHCA) annually in the United States (US) and despite many scientific advances in the field, the survival rate remains low. We seek to determine if return of spontaneous circulation (ROSC) is higher when use of emergency medical dispatch (EMD) protocols is documented for OHCA calls compared to when no EMD protocol use is documented. We also seek identify care-related processes that differ in calls that use EMD protocols. Methods This is a retrospective cohort study of U.S. adults with OHCA prior to emergency medical services (EMS) arrival using 2019 National EMS Information System data. The primary exposure was EMD usage during EMS call. The primary outcome was prehospital ROSC, and secondary outcomes included automated external defibrillator (AED) use before EMS arrival, bystander CPR, and end-of-event EMS survival (survival to the end of the EMS care at transport destination). Multivariable logistic regression adjusted for age, sex, race/ethnicity, primary insurance, rurality, initial rhythm, arrest etiology, and witnessed arrest. Results Of the 96,269 OHCA cases included, EMD use was documented in 73%. Overall, 26% of subjects achieved ROSC in EMS care. EMD subjects were more likely to achieve ROSC (27.2% vs. 23.5%, uOR 1.22, 95%CI 1.18 − 1.26) even after adjusting for subject and arrest characteristics (aOR 1.13, 95%CI 1.08 − 1.17). EMD subjects also had higher end-of-event survival (19.1% vs. 16.4%, aOR 1.20, 95%CI 1.15 − 1.25). AED use before EMS arrival was more common in the EMD group (28.3% vs. 26.3% %diff 2.0, 95%CI 1.4 to 2.6), as was CPR before EMS arrival (63.8% vs. 55.1%, difference 8.6%, 95%CI 7.9 to 9.3%). Conclusions In this retrospective analysis, the rate of ROSC was higher in adult OHCA patients when EMD protocol use was reported compared to when it was not reported. The group with documented EMD use also experienced higher rates of bystander AED use, bystander CPR, and end-of-event survival.

Racial and ethnic disparities in the treatment and outcomes for witnessed out-of-hospital cardiac arrest in Connecticut

BackgroundRacial and ethnic disparities in the treatment and outcomes for witnessed out-of-hospital cardiac arrest (OHCA) in the United States have been previously described. We sought to characterize disparities in pre-hospital care, overall survival, and survival with favorable neurological outcomes following witnessed OHCA in the state of Connecticut. MethodsWe performed a cross-sectional study to compare pre-hospital treatment and outcomes for White versus Black and Hispanic (Minority) OHCA patients submitted from Connecticut to the Cardiac Arrest Registry to Enhance Survival (CARES) between 2013 and 2021. Primary outcomes included bystander CPR use, bystander automated external defibrillator (AED) use with attempted defibrillation, overall survival, and survival with favorable cerebral function. Results2,809 patients with witnessed OHCA were analyzed (924 Black or Hispanic; 1885 White). Minorities had lower rates of bystander CPR (31.4% vs 39.1%, P = 0.002) and bystander AED placement with attempted defibrillation (10.5% vs 14.4%, P = 0.004), with lower rates of survival to hospital discharge (10.3% vs 14.8%, P = 0.001) and survival with favorable cerebral function (65.3% vs 80.2%, P = 0.003). Minorities were less likely to receive bystander CPR in communities with median annual household income >$80, 000 (OR, 0.56; 95% CI, 0.33–0.95; P = 0.030) and in integrated neighborhoods (OR, 0.70; 95% CI, 0.52–0.95; P = 0.020). ConclusionsBlack and Hispanic Connecticut patients with witnessed OHCA have lower rates of bystander CPR, attempted AED defibrillation, overall survival, and survival with favorable neurological outcomes compared to White patients. Minorities were less likely to receive bystander CPR in affluent and integrated communities.

Impact of defibrillation with automated external defibrillator by bystander before defibrillation by emergency medical system personnel on neurological outcome of out-of-hospital cardiac arrest with non-cardiac etiology

Aim of the studyAlthough defibrillation using automated external defibrillator (AED) by bystander prior to emergency medical system (EMS) arrival was associated with favorable outcomes in out-of-hospital cardiac arrest (OHCA) of cardiac cause, whether it improves outcomes of OHCA due to non-cardiac cause is not clear. We aimed to investigate the impact of defibrillation with AED by bystander before defibrillation by EMS personnel on the outcomes of OHCA of presumed non-cardiac cause. MethodsThis was a retrospective cohort study using the All-Japan Utstein registry (reference period: 2013 to 2017). We included adult patients with OHCA of presumed non-cardiac cause, who had initial shockable rhythm, and who received witnessed arrest bystander cardiopulmonary resuscitation (CPR). Exposure variable was defibrillation with AED by bystander in comparison with initial defibrillation by EMS. Logistic regression analyses were conducted to assess the association between bystander AED shock and favorable neurological outcome (Cerebral Performance Category scale 1 or 2) at one month. ResultsAmong the 1,053 patients included for analysis, 57 (5.4%) received bystander AED shock. There was no statistically significant difference in the rate of favorable neurological outcome at one month between groups [9 (15.8%) vs 109 (10.9%), p = 0.26]. Logistic regression analysis adjusted for characteristics, intervention, and time course of CPR showed no association between bystander AED shock and favorable neurological outcome [OR (95% CI): 1.63 (0.70–3.77), p = 0.25]. ConclusionIn this study, defibrillation with AED by bystander before defibrillation by EMS personnel was not associated with the favorable outcomes of OHCA of presumed non-cardiac cause.

Bystander cardiopulmonary resuscitation, automated external defibrillator use, and survival after out-of-hospital cardiac arrest

IntroductionWe aimed to investigate the association between bystander cardiopulmonary resuscitation (CPR) with and without automated external defibrillator (AED) use and neurological outcomes after out-of-hospital cardiac arrest (OHCA) in Korea. MethodsThis cross-sectional study used a nationwide Korean OHCA registry between 2015 and 2019. Patients were categorised into no bystander CPR and bystander CPR with and without AED use groups. The primary outcome was good neurological recovery at discharge. We also analysed the interaction effects of place of arrest, response time, and whether the OHCA was witnessed. ResultsIn total, 93,623 patients were included. Among them, 35,486 (37.9%) were in the no bystander CPR group, 56,187 (60.0%) were in the bystander CPR without AED use group, and 1950 (2.1%) were in the bystander CPR with AED use group. Good neurological recovery was demonstrated in 1286 (3.6%), 3877 (6.9%), and 208 (10.7%) patients in the no CPR, bystander CPR without AED use, and bystander CPR with AED use groups, respectively. Compared to the no bystander CPR group, the adjusted odds ratio (95% confidence intervals) for good neurological recovery was 1.54 (1.45–1.65) and 1.37 (1.15–1.63) in the bystander CPR without and with AED use groups, respectively. The effect of bystander CPR with AED use was more apparent in OHCAs with witnessed arrest and prolonged response time (≥8 min). ConclusionBystander CPR was associated with better neurological recovery compared to no bystander CPR; however, the benefits of AED use were not significant. Efforts to disseminate bystander AED availability and ensure proper utilisation are warranted.

Effect of Smartphone Dispatch of Volunteer Responders on Automated External Defibrillators and Out-of-Hospital Cardiac Arrests

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). 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). 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. 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. Overall bystander AED attachment, including those attached by volunteer responders and lay volunteers who did not use the smartphone application. 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. 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. ClinicalTrials.gov Identifier: NCT02992873.

Pediatric and adult Out-of-Hospital cardiac arrest incidence within and near public schools in British Columbia: Missed opportunities for Systematic AED deployment strategies

BackgroundSystematic automated external defibrillator(AED) placement in schools may improve pediatric out-of-hospital cardiac arrest(OHCA) survival. To estimate their utility, we identified school-located pediatric and adult OHCAs to estimate the potential utilization of school-located AEDs. Further, we identified all OHCAs within an AED-retrievable distance of the school by walking, biking, and driving. MethodsWe used prospectively collected data from the British Columbia(BC) Cardiac Arrest Registry(2013–2020), and geo-plotted all OHCAs and schools(n = 824) in BC. We identified adult and pediatric(age < 18 years) OHCAs occurring in schools, as well as nearby OHCAs for which a school-based externally-placed AED could be retrieved by a bystander prior to emergency medical system(EMS) arrival. ResultsOf 16,409 OHCAs overall in the study period, 28.6 % occurred during school hours. There were 301 pediatric OHCAs. 5(1.7 %) occurred in schools, of whom 2(40 %) survived to hospital discharge. Among both children and adults, 28(0.17 %) occurred in schools(0.0042/school/year), of whom 21(75 %) received bystander resuscitation, 4(14 %) had a bystander AED applied, and 14(50 %) survived to hospital discharge. For each AED, an average of 0.29 OHCAs/year(95 % CI 0.21–0.37), 0.93 OHCAs/year(95 % CI 0.69–1.56) and 1.69 OHCAs/year(95 % CI 1.21–2.89) would be within the potential retrieval distance of a school-located AED by pedestrian, cyclist and automobile retrieval, respectively, using the median EMS response times. ConclusionWhile school-located OHCAs were uncommon, outcomes were favourable. 11.1% to 60.9% of all OHCAs occur within an AED-retrievable distance to a school, depending on retrieval method. Accessible external school-located AEDs may improve OHCA outcomes of school children and in the surrounding community.

Bystander-initiated cardiopulmonary resuscitation and automated external defibrillator use after out-of-hospital cardiac arrest: Uncovering disparities in care and survival across the urban–rural spectrum

AimTo evaluate the association between bystander cardiopulmonary resuscitation (CPR), automated external defibrillator (AED) use, and survival after out-of-hospital cardiac arrest (OHCA) across the urban–rural spectrum. MethodsThis was a retrospective cohort study of 325,477 adult OHCAs within the Cardiac Arrest Registry to Enhance Survival from 2013 to 2019. Bystander interventions were categorized into no bystander intervention, bystander CPR alone, and bystander AED use (with or without CPR). The primary outcome was survival to hospital discharge with good neurological outcome. Multivariable logistic regression was used to evaluate the association between bystander interventions and survival by geographical status (urban, suburban, large rural, small town, or rural). ResultsBystander CPR alone occurred most often in rural areas (50.8%), and least often in urban areas (35.4%). Bystander AED use in public settings was similar across the urban–rural spectrum (10.5–13.1%). Survival with good neurological outcome varied for urban (8.1%), suburban (7.7%), large rural (9.1%), small town (7.1%), and rural areas (6.1%). In comparison to no bystander intervention, the adjusted odds ratios (95% confidence intervals) for bystander AED use and survival were 2.57 (2.37–2.79) in urban areas, 2.58 (1.81–3.67) in suburban areas, 1.99 (1.44–2.76) in large rural areas, 1.90 (1.27–2.86) in small towns, and 3.05 (1.99–4.68) in rural areas. Bystander CPR alone was also associated with survival in all areas (adjusted odds ratio range: 1.29–1.45). There was no strong evidence of interaction between bystander interventions and geographical status on the primary outcome (p = 0.63). ConclusionBystander CPR and AED use are associated with positive clinical outcomes after OHCA in all areas along the urban–rural spectrum.

Inverse Association Between Bystander Use of Audiovisual Feedback From an Automated External Defibrillator and Return of Spontaneous Circulation.

BackgroundTreatment with an automated external defibrillator (AED) improves outcome in out‐of‐hospital cardiac arrest (OHCA). Audiovisual feedback from an AED may assist bystanders achieve higher quality cardiopulmonary resuscitation. However, the association between audiovisual feedback and clinical outcomes is not well assessed in real‐life OHCA. The aim of this study was to assess the association between audiovisual feedback from an AED used in bystander resuscitation with rates of return of spontaneous circulation (ROSC) and 30‐day survival in a real‐life cohort of patients with OHCA.Methods and ResultsWe included 325 patients treated with bystander AED use before arrival of emergency medical services during 2016 to 2019 from the Capital Region of Denmark. Patients were divided into a “feedback” and a “nonfeedback” group, depending on presence of audiovisual feedback from the AED. Audiovisual feedback was defined as voice prompts with continuous feedback to ongoing resuscitation. Rates of ROSC upon hospital admission and 30‐day survival were assessed, and univariate and multivariable models were applied to decide the association to audiovisual feedback. Multivariable models were adjusted for sex, age, primary heart rhythm, and location of OHCA. A total of 155 (48%) patients had a bystander AED applied with audiovisual feedback and 170 (52%) without audiovisual feedback. A lower rate of ROSC was found in the feedback group compared with the nonfeedback group (33% [n=51] versus 45% [n=76]; P=0.03). No association was observed between AV feedback and 30‐day survival (feedback=27% [n=42] and nonfeedback=31% [n=53]; P=0.49). In the unadjusted logistic regression model, audiovisual feedback was associated with a decreased chance of ROSC (odds ratio, 0.61; 95% CI, 0.38–0.95; P=0.03), which remained significant after adjusted analysis (odds ratio, 0.53; 95% CI, 0.29–0.97; P=0.04), whereas we found no significant association between audiovisual feedback and 30‐day survival in the unadjusted and adjusted analyses.ConclusionsAudiovisual feedback from an AED used by bystanders was associated with a lower chance of ROSC at hospital admission, but we found no significant difference in 30‐day survival. Focus on early and correct bystander cardiopulmonary resuscitation and AED use remain key for OHCA survival.

Bystander cardiopulmonary resuscitation and automated external defibrillator use after out-of-hospital cardiac arrest: uncovering differences in care and survival across the urban-rural spectrum

Abstract Background Despite regional variation in survival following out-of-hospital cardiac arrest (OHCA), few studies have investigated urban-rural differences in the provision of care and outcomes after OHCA. To better understand the role of pre-hospital care across the urban-rural spectrum, we compared the effects of bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use on survival after OHCA between geographical settings. Methods This retrospective study (2013–2019) used all adult, non-traumatic, and treated OHCAs registered in the Cardiac Arrest Registry to Enhance Survival. The urban/rural status of arrest locations were classified at the census tract level as urban, suburban, large rural, small town, or rural, using the Rural-Urban Commuting Area classification system (Figure). Bystander interventions were grouped into three categories, including no bystander intervention, bystander CPR alone, and bystander AED use (with CPR). The primary outcome of interest was survival to hospital discharge with good neurological outcome. Multivariable logistic regression models were developed to assess the association between bystander interventions and survival with good neurological outcome by urban/rural status, adjusting for relevant covariates. Results A total of 325,281 patients were included. Bystander CPR alone occurred most often in rural areas (50.8%), and least often in urban areas (35.4%). Bystander AED use varied by urban/rural status (1.7%-2.9%), with large rural (2.9%) and rural areas (2.4%) reporting the highest rates. Survival to hospital discharge with good neurological outcome differed for urban (8.1%), suburban (7.7%), large rural (9.1%), small town (7.1%), and rural areas (6.1%). In all areas, patients who received bystander AED use or bystander CPR alone were more likely to achieve survival with good neurological outcome than patients who received no bystander intervention. The effect of bystander AED use on survival was stronger than bystander CPR alone in urban, suburban, and rural areas (no overlap of confidence bands), whereas no significant differences between these two bystander intervention groups were observed in large rural areas or small towns (overlap of confidence bands) (Table). Conclusions Bystander CPR and AED use are critical components of the response to OHCA across the urban-rural spectrum. The relative impact of bystander interventions on survival varied based on the geographical location of arrests, despite adjusting for numerous potential confounding variables, such as response time. It is possible that unmeasured factors, such as time from collapse to bystander intervention, patient factors, AED accessibility, and CPR quality are contributing to these observed differences. Future research is needed to better understand the response to OHCA across the urban-rural spectrum, which may inform policies for community-specific emergency protocols and planning. Funding Acknowledgement Type of funding sources: None.

The role of bystander-initiated basic life support in exercise-related sudden cardiac arrest: a systematic review

Abstract Background Sudden cardiac arrest (SCA) is the leading cause of death amongst athletes and a common cause of death during exercise. Although the provision of cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use by bystanders improves outcomes after SCA, the impact of these interventions within exertional settings requires further investigation. Purpose The purpose of this systematic review was to evaluate the role of bystander CPR and AED use on survival after exercise-related SCA. Methods Literature searches in MEDLINE, EMBASE, PubMed, CINAHL, SPORTDiscus, and Cochrane Library were queried from inception until November 2020 using a comprehensive search strategy. Grey literature searches of Google Scholar and CADTH Grey Matters were also performed. Abstract screening, full-text review, and data extraction of eligible studies was conducted independently by two reviewers, with any conflicts discussed until consensus reached. Eligible studies included observational research studies assessing a population of exercise-related SCAs (defined as an out-of-hospital cardiac arrest which occurred during exercise or within 1-hour of cessation of activity), where the rate of bystander CPR and/or AED use was provided, and survival outcomes were reported. Abstracts, studies with overlapping patient data, and/or studies of n≤10 were excluded. Among studies with similar populations, the overall rates (median, range) of bystander CPR, AED use, and survival outcomes were calculated. Results A total of 3,718 records were identified from literature searches, and after removal of duplicates, 2,850 were screened. Among those screened, 176 articles were selected for full-text review, of which 29 studies were included in this review. Majority of included studies were cohort studies (2 case series and 2 cross-sectional), with a median sample size of 91. Most patients who suffered from an exercise-related SCA were male, middle-aged, and presented with a shockable arrest rhythm. The median rate of bystander CPR reported amongst 22 studies was 71% (31%-100%), whereas the median rate of bystander AED use reported amongst 16 studies was 31% (2%-100%) (Table). Among the 19 studies which reported the rate of survival to hospital discharge, survival ranged from 11% to 77%, with a median rate of 32% (Table). Patients who survived to hospital discharge more frequently received bystander CPR and had an AED applied than patients who died (Figure). Conclusions Survival rates after exercise-related SCA were higher than previously reported in other settings not related to exercise. These outcomes are likely related to a higher rate of bystander interventions in exertional or sport-specific settings. The findings of this review encourage layperson education in basic life support, the availability of AEDs in exercise facilities, and the development of emergency action plans to provide point-of-performance cardiac care in exertional settings. Funding Acknowledgement Type of funding sources: None.

Out-of-Hospital Cardiac Arrest Bystander Defibrillator Search Time and Experience With and Without Directional Assistance: A Randomized Simulation Trial in a Community Setting.

Probability of survival after out-of-hospital cardiac arrest (OHCA) doubles when a bystander initiates cardiopulmonary resuscitation and uses an automated external defibrillator (AED) rapidly. National, state, and community efforts have increased placement of AEDs in public spaces; however, bystander AED use remains less than 2% in the United States. Little is known about the effect of giving bystanders directional assistance to the closest public access AED. We conducted 35 OHCA simulations using a life-sized manikin with participants aged 18 through 65 years who searched for public access AEDs in 5 zones on a university campus. Zones varied by challenges to pedestrian AED acquisition and number of fixed AEDs. Participants completed 2 searches-first unassisted and then with verbal direction to the closest AED-and we compared AED delivery times. We conducted pretest and posttest surveys. In all 5 zones, the median time from simulated OHCA onset to AED delivery was lower when the bystander received directional assistance. Time savings (minutes:seconds) varied by zone, ranging from a median of 0:53 (P = 0.14) to 3:42 (P = 0.02). Only 3 participants immediately located the closest AED without directional assistance; more than half reported difficulty locating an AED. These findings may inform strategies to ensure that AEDs are consistently marked and placed in visible, accessible locations. Continued emphasis on developing strategies to improve lay bystanders' ability to locate and use AEDs may improve AED retrieval times and OHCA outcomes.

Barriers to bystanders defibrillation: A national survey on public awareness and willingness of bystanders defibrillation☆

After years of setting up public automated external defibrillators (AEDs), the rate of bystander AED use remains low all over the world. This study aimed to assess the public awareness and willingness of bystanders to use AEDs and to investigate the awareness on the Good Samaritan Law (GSL) and the factors associated with the low rate of bystander AED use. Using stratified random sampling, national telephone interviews were conducted using an author-designed structured questionnaire. The results were weighted to match the census data in Taiwan. The factors associated with public awareness and willingness of bystanders to use AEDs were analysed by logistic regression. Of the 1073 respondents, only 15.2% had the confidence to recognise public AEDs, and 5.3% of them had the confidence to use the AED. Concerns on immature technique and legal issues remain the most common barriers to AED use by bystanders. Moreover, only 30.8% thought that the public should use AEDs at the scene. Few respondents (9.6%) ever heard of the GSL in Taiwan, and less than 3% understood the meaning of GSL. Positive awareness on AEDs was associated with high willingness of bystanders to use AEDs. Respondents who were less likely to use AEDs as bystanders were healthcare personnel and women. The importance of active awareness and the barriers to the use of AEDs among bystanders seemed to have been underestimated in the past years. The relatively low willingness to use AEDs among bystander healthcare providers and women needs further investigation.

Abstract 233: Characterizing Impact of State Legislation on Cardiac Arrest Outcomes at K-12 Schools

Background: Cardiac arrests that occur in schools are infrequent, but high-profile events. Many states have enacted school specific legislation regarding automated external defibrillators (AEDs) placement, CPR training and emergency response plans (EAP). Objective/Aim: To characterize out-of-hospital cardiac arrests (OHCA) that occur in K-12 schools; and, assess the relationship of U.S. state AED and CPR laws to outcomes of in school cardiac arrests. Methods: A retrospective review of in school OHCA was completed with data from the National EMS Information System (NEMSIS) 3.4 database, calendar years 2017-2018. Study subjects were non-traumatic OHCA occurring prior to EMS arrival on K-12 school grounds. Additionally, we conducted a search of Westlaw (Thomson Reuters) to identify current school specific AED, CPR and EAP laws for all 50 states, and created a structured taxonomy for these laws. Datasets were linked by an honest broker and the K-12 school CPR and AED provisions were compared to state legislation. Results: During the study period, there were 454 cases of in school cardiac arrest out of the 25.3 million incidents submitted to NEMSIS. We excluded 140, thus leaving 314 arrests for analysis. The average age was 46.7 (SD=24.1), most were over 18 years old (79.4%), and male 221 (70.4%). Bystander CPR (BCPR) was performed in 240 (76.4%) of cases, bystander AEDs were used in 160 (51.0%) cases, and 107 (34.1%) patients received an AED shock. State AED and CPR laws required student CPR training in 78%, school AED placement in 46%, teacher CPR certification in 14%, and school specific cardiac emergency response plans in 32%. We found no increase in BCPR or AED placement in states with school CPR, AED or EAP legislation. These findings persisted regardless of patient age, school type, or legislative mandate (all P &gt; 0.05). Conclusion: Despite the perceived benefit of legislation supporting CPR and AED use in schools, we identified no improved provision of BCPR or AED use in schools in states with such legislation. Given the high proportions of BCPR and AED in states with and without statutes, we believe this data suggests that non-legislative initiatives, which exist in many states, may be an important driver of emergency cardiac care in K-12 schools.

P066: A quality improvement project to improve access to automated external defibrillators in the Niagara region community

Background: Over 35,000 Canadians lose their lives to cardiac arrest each year. CPR and automated external defibrillator (AED) use are modifiable factors. Survival rates drop by 7-10% each minute that defibrillation is delayed, and survival rates are less than 5% after 12 minutes of ventricular fibrillation which stresses the need for bystander AED use in out-of-hospital arrests. Niagara Region lacks a publicly accessible registry of AEDs. AED access is a major focus in King County, Washington which has higher survival rates and has all AEDs registered with Emergency Medical Services. Aim Statement: This project aims to log 100 or more AEDs within a year into a publicly accessible registry and to connect the registry information to medical trainees in the Niagara region and all employees of the Niagara Health System involved in patient care. Measures &amp; Design: PulsePoint is an application used to register AEDs within the Niagara region. PulsePoint allows users to geotag AEDs while tracking data entries. Over 16 weeks, 4 PDSA cycles tested the effectiveness of logging methods for AEDs including opportunistic logging, daily emailed reminders, and contacting organizations with high likelihood of having an AED. Information about the project and registry was shared with residents and medical students in Niagara. A second phase of cycles involves relaying information to Niagara Health system employees and the medical community. A final cycle will target a broader group of local organizations with intermediate probability of having AEDs. Primary outcome measures include the numbers of regional AEDs logged and members reached by knowledge sharing cycles. Evaluation/Results: PulsePoint was found to be an effective, free, publicly accessible resource to log AEDs within the Niagara region. The initial round of 4 PDSA cycles added a total of 56 new AEDs within the region, which were logged into PulsePoint app and the Excel spreadsheet. Through the fourth PDSA cycle, 136 businesses were contacted and made aware of the project and the AED application. In addition,138 health-related colleagues and medical students were contacted to raise awareness. PDSA cycles five through eight are currently ongoing or in the planning stages. Discussion/Impact: Raising awareness among emergency services and sharing information about the registry to local CPR training providers will be paramount. Creating awareness of PulsePoint and installing AEDs in locations that currently lack such devices could ultimately improve cardiac arrest survival rates within Niagara Region.

Abstract 53: Aerial Drone versus Ground Search for Delivery of an Automated External Defibrillator (AED) for Out-of-hospital Cardiac Arrest: A Comparison of Elapsed Time and Bystander Experience in a Community Setting

Background: An estimated 350,000 individuals experience out-of-hospital cardiac arrest (OHCA) in the United States (US) annually; only approximately 10% survive. The probability of survival after OHCA doubles when a bystander uses an automated external defibrillator (AED) before emergency management services arrives; however, bystander AED use is less than 2% in the US. We conducted a series of randomized trials in a community setting comparing the delivery of an AED by aerial drone to that of a bystander searching for and retrieving an AED from fixed locations in the area. Methods: We conducted 35 simulation trials of an OHCA using a life-sized manikin accompanied by two participants, paired by gender and age (18-34, 35-49, 50-65 years), in a community setting, with seven trials per zone in five distinct zones. Zones represented different environmental challenges to drone navigation and pedestrian acquisition of an AED and varied in number of fixed AEDs in the area (range 1-8 AEDs in a 600 ft radius from the OHCA site). We used a DJI Matrice 600 Pro drone, modified to carry a standard AED, flying autonomously from a preprogrammed flight path to the OHCA site. Drone launch sites varied by zone and ranged from 800 to 1300 ft from the OHCA site. We randomized participants either to call a mock 9-1-1 telecommunicator who would initiate the drone’s flight sequence, or to conduct a ground search to locate and retrieve an AED from a fixed location. We compared the delivery time of an AED by drone to that of an AED acquired by ground search. We conducted pre- and post-trial interviews with each participant to query perceptions. Results: We conducted 18 trials with women and 17 with men. These included 15, 11, and 9 trials across the three age strata, respectively. The average time (minutes: seconds) from onset of the simulated OHCA to AED delivery was 1:21 faster by drone (4:45, standard deviation (SD) = 0.34) compared to ground search (6:06, SD = 3:21). In 71% of trials (n=25 of 35), the drone delivered the AED to the event site within 5 minutes, compared to 51% (n=18 of 35) of ground searches (p=0.09). Median AED delivery time was faster by drone than by ground search in four of the five zones (range 0:17 to 2:56). Ground search was faster than the drone in one zone with 7 AEDs within 600 ft of the simulated OHCA event site and the shortest average distance to an AED (254 ft) of all the five zones. Among participants randomized to call for the drone, 89% reported that they felt comfortable as the drone approached, and 72% reported having no safety concerns. Nearly half of participants randomized to conduct a ground search reported difficulty finding an AED. Conclusion: Our study suggests that drone delivery of an AED to the site of an OHCA is feasible and acceptable in a community setting. Drones may provide more timely access to early defibrillation compared to bystander search and acquisition of an AED from the surrounding area.

Effectiveness of a community based out-of-hospital cardiac arrest (OHCA) interventional bundle: Results of a pilot study

Background70% of Out-of-hospital cardiac arrests (OHCA) in Singapore occur in residential areas, and are associated with poorer outcomes. We hypothesized that an interventional bundle consisting of Save-A-life (SAL) initiative (cardiopulmonary resuscitation (CPR)/automated external defibrillator (AED) training and public-housing AED installation), dispatcher-assisted CPR (DA-CPR) program and myResponder (mobile application) will improve OHCA survival. MethodsThis is pilot data from initial implementation of a stepped-wedge, before-after, real-world interventional bundle in six selected regions. Under the SAL initiative, 30,000 individuals were CPR/AED trained, with 360 AEDs installed. Data was obtained from Singapore’s national OHCA Registry. We included all adult patients who experienced OHCA in Singapore from 2011 to 2016 within study regions, excluding EMS-witnessed cases and cases due to trauma/drowning/ electrocution. Cases occurring before and after intervention were allocated as control and intervention groups respectively. Survival was assessed via multivariable logistic regression. Results1241 patients were included for analysis (Intervention: 361; Control: 880). The intervention group had higher mean age (70 vs 67 years), survival (3.3% [12/361] vs. 2.2% [19/880]), pre-hospital return of spontaneous circulation (ROSC) (9.1% [33/361] vs 5.1% [45/880]), bystander CPR (63.7% [230/361] vs 44.8% [394/880]) and bystander AED application (2.8% [10/361] vs 1.1% [10/880]). After adjusting for age, gender, race and significant covariates, the intervention was associated with increased odds ratio (OR) for survival (OR 2.39 [1.02–5.62]), pre-hospital ROSC (OR 1.94 [1.15–3.25]) and bystander CPR (OR 2.29 [1.77–2.96]). ConclusionThe OHCA interventional bundle (SAL initiative, DA-CPR, myResponder) significantly improved survival and is being scaled up as a national program.