The use of trained volunteers in the response to out-of-hospital cardiac arrest - the GoodSAM experience

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

Background

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

Methods

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

Results

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

Conclusion

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

Volunteer Responder Interventions in Out-of-Hospital Cardiac Arrest in Urban, Suburban, and Rural Areas

BACKGROUND

Patients with out-of-hospital cardiac arrest (OHCA) in rural areas experience longer emergency response times and have lower survival rates compared with patients in urban areas. Volunteer responders might improve care and outcomes for patients with OHCA specifically in rural areas. Therefore, we investigated volunteer responder interventions based on the degree of urbanization.

METHODS AND RESULTS

We included 1310 OHCAs from 3 different regions in Denmark where volunteer responders had arrived at the OHCA location. The location was classified as urban, suburban, or rural according to the Eurostat Degree of Urbanization Tool. A logistic regression model was used to examine associations between the degree of urbanization and volunteer responder arrival before emergency medical services, cardiopulmonary resuscitation, or defibrillation. We found the odds for volunteer responder arrival before emergency medical services more than doubled in rural areas (odds ratio [OR], 2.60 [95% CI, 1.91-3.53]) and suburban areas (OR, 2.05 [95% CI, 1.56-2.69]) compared with urban areas. In OHCA cases where volunteer responders arrived first, odds for bystander cardiopulmonary resuscitation was tripled in rural areas (OR, 3.83 [95% CI, 1.64-8.93]) and doubled in suburban areas (OR, 2.27 [95% CI, 1.17-4.41]) compared with urban areas. Bystander defibrillation was more common in suburban areas (OR, 1.53 [95% CI, 1.02-2.31]), where almost 1 out of 4 patients received bystander defibrillation, compared with urban areas.

CONCLUSIONS

Volunteer responders are significantly more likely to arrive before emergency medical services in rural and suburban areas than in urban areas. Patients with OHCA received more cardiopulmonary resuscitation in rural and suburban areas and more defibrillation in suburban areas than in urban areas.

Automated and app-based activation of first responders for prehospital cardiac arrest: an analysis of 16.500 activations of the KATRETTER system in Berlin

BACKGROUND

Bystander CPR is one of the main independent factors contributing to better survival after out-of-hospital cardiac arrest. Simultaneously, the rate of bystander CPR in Germany is below the European average. First responder applications (apps) contribute to reducing the time period without CPR (no-flow time) until professional help can arrive on-scene.

METHODS

The KATRETTER app was introduced in Berlin as one of the first apps in Europe which do not require any medical qualifications to register as a first responder. The activation of volunteer first responders for suspected cardiac arrest cases through the Berlin Emergency Medical Services integrated control center was evaluated based on data collected between 16 Oct 2020 and 16 Oct 2022. Our descriptive analysis includes the number of registered first responders, number of activations, the number and percentages of accepted activations, as well as all reports where first responders arrived at the scene.

RESULTS

As of 15 Oct 2022, a total of 10,102 first responders were registered in the state of Berlin. During this specified period, there were 16.505 activations of the system for suspected out-of-hospital cardiac arrest. In 38.4% of the accepted cases, first responders documented patient contact, and in 34.6% of cases with patient contact, CPR was performed. Only 2% of registered first responders did not have any medical qualifications.

CONCLUSIONS

Smartphone-based first responder applications should not be understood as a means of alerting professional help, but rather like a digitally amplified "call for help" in the vicinity of an emergency location. A large number of first responders can be recruited within 24 months, without large-scale public relations work necessary. No qualifications were required to become a first responder, contributing to a low-threshold registration process with the effect of a more widespread distribution of the app and cost reduction during implementation.

A study protocol for a cluster-randomised controlled trial of smartphone-activated first responders with ultraportable defibrillators in out-of-hospital cardiac arrest: The First Responder Shock Trial (FIRST)

Objective

To describe the First Responder Shock Trial (FIRST), which aims to determine whether equipping frequently responding, smartphone-activated (GoodSAM) first responders with an ultraportable AED can increase 30-day survival rates in OHCA.

Methods

The FIRST trial is an investigator-initiated, bi-national (Victoria, Australia and New Zealand), registry-nested cluster-randomised controlled trial where the unit of randomisation is the smartphone-activated (GoodSAM) first responder. High-frequency GoodSAM responders are randomised 1:1 to receive an ultraportable, single-use AED or standard alert procedures using the GoodSAM app.The primary outcome is survival to 30 days. The secondary outcome measures (shockable rhythm, return of spontaneous circulation, event survival, and time to first shock delivery) are routinely collected by OHCA registries in both regions. The trial was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR) (Registration: ACTRN12622000448741) on 22 March 2022.

Results

The trial started in November 2022 and the last patient is expected to be enrolled in November 2024. We aim to detect a 7% increase in the proportion of 30-day survivors, from 9% in patients attended by control responders to 16% in patients attended by responders randomised to the ultraportable AED intervention arm. With 80% power, an alpha of 0.05, a cluster size of 1.5 and a coefficient of variation for cluster sizes of 1, the sample size required to detect this difference is 714 (357 per arm).

Conclusion

The FIRST study will increase our understanding of the potential role of portable AED use by smartphone-activated community responders and their impact on survival outcomes.

Predictive Dispatch of Volunteer First Responders: Algorithm Development and Validation

BACKGROUND

Smartphone-based emergency response apps are increasingly being used to identify and dispatch volunteer first responders (VFRs) to medical emergencies to provide faster first aid, which is associated with better prognoses. Volunteers' availability and willingness to respond are uncertain, leading in recent studies to response rates of 17% to 47%. Dispatch algorithms that select volunteers based on their estimated time of arrival (ETA) without considering the likelihood of response may be suboptimal due to a large percentage of alerts wasted on VFRs with shorter ETA but a low likelihood of response, resulting in delays until a volunteer who will actually respond can be dispatched.

OBJECTIVE

This study aims to improve the decision-making process of human emergency medical services dispatchers and autonomous dispatch algorithms by presenting a novel approach for predicting whether a VFR will respond to or ignore a given alert.

METHODS

We developed and compared 4 analytical models to predict VFRs' response behaviors based on emergency event characteristics, volunteers' demographic data and previous experience, and condition-specific parameters. We tested these 4 models using 4 different algorithms applied on actual demographic and response data from a 12-month study of 112 VFRs who received 993 alerts to respond to 188 opioid overdose emergencies. Model 4 used an additional dynamically updated synthetic dichotomous variable, frequent responder, which reflects the responder's previous behavior.

RESULTS

The highest accuracy (260/329, 79.1%) of prediction that a VFR will ignore an alert was achieved by 2 models that used events data, VFRs' demographic data, and their previous response experience, with slightly better overall accuracy (248/329, 75.4%) for model 4, which used the frequent responder indicator. Another model that used events data and VFRs' previous experience but did not use demographic data provided a high-accuracy prediction (277/329, 84.2%) of ignored alerts but a low-accuracy prediction (153/329, 46.5%) of responded alerts. The accuracy of the model that used events data only was unacceptably low. The J48 decision tree algorithm provided the best accuracy.

CONCLUSIONS

VFR dispatch has evolved in the last decades, thanks to technological advances and a better understanding of VFR management. The dispatch of substitute responders is a common approach in VFR systems. Predicting the response behavior of candidate responders in advance of dispatch can allow any VFR system to choose the best possible response candidates based not only on ETA but also on the probability of actual response. The integration of the probability to respond into the dispatch algorithm constitutes a new generation of individual dispatch, making this one of the first studies to harness the power of predictive analytics for VFR dispatch. Our findings can help VFR network administrators in their continual efforts to improve the response times of their networks and to save lives.

One-year quality-of-life outcomes of cardiac arrest survivors by initial defibrillation provider

OBJECTIVE

To assess the long-term functional and health-related quality-of-life (HRQoL) outcomes for out-of-hospital cardiac arrest (OHCA) survivors stratified by initial defibrillation provider.

METHODS

This retrospective study included adult non-traumatic OHCA with initial shockable rhythms between 2010 and 2019. Survivors at 12 months after arrest were invited to participate in structured telephone interviews. Outcomes were identified using the Glasgow Outcome Scale-Extended (GOS-E), EuroQol-5 Dimension (EQ-5D), 12-Item Short Form Health Survey and living and work status-related questions.

RESULTS

6050 patients had initial shockable rhythms, 3211 (53.1%) had a pulse on hospital arrival, while 1879 (31.1%) were discharged alive. Bystander defibrillation using the closest automated external defibrillator had the highest survival rate (52.8%), followed by dispatched first responders (36.7%) and paramedics (27.9%). 1802 (29.8%) patients survived to 12-month postarrest; of these 1520 (84.4%) were interviewed. 1088 (71.6%) were initially shocked by paramedics, 271 (17.8%) by first responders and 161 (10.6%) by bystanders. Bystander-shocked survivors reported higher rates of living at home without care (87.5%, 75.2%, 77.0%, p<0.001), upper good recovery (GOS-E=8) (41.7%, 30.4%, 30.6%, p=0.002) and EQ-5D visual analogue scale (VAS) ≥80 (64.9%, 55.9%, 52.9%, p=0.003) compared with first responder and paramedics, respectively. After adjustment, initial bystander defibrillation was associated with higher odds of EQ-5D VAS ≥80 (adjusted OR (AOR) 1.56, 95% CI 1.15-2.10; p=0.004), good functional recovery (GOS-E ≥7) (AOR 1.53, 95% CI 1.12-2.11; p=0.009), living at home without care (AOR 1.77, 95% CI 1.16-2.71; p=0.009) and returning to work (AOR 1.72, 95% CI 1.05-2.81; p=0.031) compared with paramedic defibrillation.

CONCLUSION

Survivors receiving initial bystander defibrillation reported better functional and HRQoL outcomes at 12 months after arrest compared with those initially defibrillated by paramedics.

Content validation of the HeartRunner questionnaire to volunteer responders dispatched to out-of-hospital cardiac arrests: A qualitative study

Aim

To increase survival after out-of-hospital cardiac arrest (OHCA) in Denmark, volunteer responders are activated through a smartphone application (HeartRunner app) to quickly locate an automated external defibrillator (AED) and assist with cardiopulmonary resuscitation (CPR). All dispatched volunteer responders who have been activated by the app receive a follow-up questionnaire to evaluate their participation in the programme. The content of the questionnaire has never been thoroughly evaluated. We therefore aimed to validate the content of the questionnaire.

Methods

Content validity was evaluated qualitatively. It was based on individual interviews with three experts, along with three focus group interviews and five individual interviews using cognitive interview technique, with a total of 19 volunteer responders. The interviews were also used to inform refinements of the questionnaire to reach improvements in content validity.

Results

The initial questionnaire consisted of 23 items. After the content validation process, the questionnaire consisted of 32 items; with the addition of 9 new items. Specifically, some original items were merged into one item or divided into separate items. Moreover, we revised the order of items, some sentences were rephrased or reworded, an introduction and headlines to different sections were added, and skip logic were incorporated to hide non-relevant items.

Conclusion

Our findings support the importance of validating questionnaires to ensure accuracy of survey instruments. Validation led to modifications of the questionnaire, and we propose a new version of the HeartRunner questionnaire. Our findings support the content validity of the final HeartRunner questionnaire. The questionnaire may allow the collection of quality data to evaluate and improve volunteer responder programmes.

Racial and Ethnic Disparities in the Treatment and Outcomes for Witnessed Out-of-Hospital Cardiac Arrest in Connecticut

BACKGROUND

Racial 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.

METHODS

We 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.

RESULTS

2,809 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).

CONCLUSIONS

Black 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.

The association between the experience of lay responders and response interval to medical emergencies in a rural area: an observational study

AIM

The aim of this retrospective observational study was to determine how response intervals correlated to the experience of the community first responders (CFRs) using data collected from the Danish Island of Langeland via a global positioning system (GPS)-based system.

METHODS

All medical emergency calls involving CFRs in the time period from 21st of April 2012 to 31st of December 2017 were included. Each emergency call activated 3 CFRs. Response intervals were calculated using the time from when the system alerted the CFRs to CFR time of arrival at the emergency site measured by GPS. CFRs response intervals were grouped depending on their level of experience according to ≤ 10, 11-24, 25-49, 50-99, ≥ 100 calls accepted and arrived on-site.

RESULTS

A total of 7273 CFR activations were included. Median response interval for the CFR arriving first on-site (n = 3004) was 4:05 min (IQR 2:42-6:01) and median response interval for the arrival of the CFR with an automated external defibrillator (n = 2594) was 5:46 min (IQR 3:59-8:05). Median response intervals were 5:53 min (3:43-8:29) for ≤ 10 calls (n = 1657), 5:39 min (3:49-8:01) for 11-24 calls (n = 1396), 5:45 min (3:49-8:00) for 25-49 calls (n = 1586), 5:07 min (3:38-7:26) for 50-99 calls (n = 1548) and 4:46 min (3:14-7:32) for ≥ 100 calls (n = 1086) (p < 0.001). There was a significant negative correlation between experience and response intervals (p < 0.001, Spearman's rho = -0.0914).

CONCLUSION

This study found an inverse correlation between CFR experience and response intervals, which could lead to increased survival after a time-critical incident.

Association Between Number of Volunteer Responders and Interventions Before Ambulance Arrival for Cardiac Arrest

BACKGROUND

Volunteer responder (VR) programs for activation of laypersons in out-of-hospital cardiac arrest (OHCA) have been deployed worldwide, but the optimal number of VRs to dispatch is unknown.

OBJECTIVES

The purpose of this study was to investigate the association between the number of VRs arriving before Emergency Medical Services (EMS) and the proportion of bystander cardiopulmonary resuscitation (CPR) and defibrillation.

METHODS

We included OHCAs not witnessed by EMS with VR activation from the Capital Region (September 2, 2017, to May 14, 2019) and the Central Region of Denmark (November 5, 2018, to December 31, 2019). We created 4 groups according to the number of VRs arriving before EMS: 0, 1, 2, and 3 or more. Using a logistic regression model adjusted for EMS response time, we examined associations between the number of VRs arriving before EMS and bystander CPR and defibrillation.

RESULTS

We included 906 OHCAs. The adjusted ORs for bystander CPR were 2.40 (95% CI: 1.42-4.05), 3.18 (95% CI: 1.39-7.26), and 2.70 (95% CI: 1.32-5.52) when 1, 2, or 3 or more VRs arrived before EMS (reference), respectively. The adjusted OR for bystander defibrillation increased when 1 (1.97 [95% CI: 1.12-3.52]), 2 (2.88 [95% CI: 1.48-5.58]), or 3 or more (3.85 [95% CI: 2.11-7.01]) VRs arrived before EMS (reference). The adjusted OR of bystander defibrillation increased to 1.95 (95% CI: 1.18-3.22) when ≥3 VRs arrived first compared with 1 VR arriving first (reference).

CONCLUSIONS

We found an association of increased bystander CPR and defibrillation when 1 or more VRs arrived before the EMS with a trend toward increased bystander defibrillation with increasing number of VRs arriving first.

Factors associated with the arrival of smartphone-activated first responders before the emergency medical services in Out-of-Hospital cardiac arrest dispatch

BACKGROUND

First responder programs were developed to speed up access to cardiopulmonary resuscitation and defibrillation for out-of-hospital cardiac arrest (OHCA) victims. Little is known about the factors influencing the efficiency of the first responders arriving before the EMS and, therefore, effectively contributing to the chain of survival.

OBJECTIVES

The primary objective of this retrospective observational study was to identify the factors associated with first responders' arrival before EMS in the context of a regional first responder program arranged to deliver automated external defibrillators on suspected OHCA scenes.

METHODS

Eight hundred ninety-six dispatches where FRs intervened were collected from 2018 to 2022. A robust Poisson regression was performed to estimate the role of the time of day, the immediate availability of a defibrillator, the type of first responder, distances between the responder, the event and the dispatched vehicle, and the nearest available defibrillator on the probability of responder arriving before EMS. Moreover, a geospatial logistic regression model was built.

RESULTS

Responders arrived before EMS in 13.4% of dispatches and delivered a shock in 0.9%. The immediate availability of a defibrillator for the responder (OR = 3.24) and special categories such as taxi drivers and police (OR = 1.74) were factors significantly associated with the responder arriving before EMS. Moreover, a geospatial effect suggested that first responder programs may have a greater impact in rural areas.

CONCLUSIONS

When dispatched to OHCA scenes, responders already carrying defibrillators could more probably reach the scene before EMS. Special first responder categories are more competitive and should be further investigated.

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.

More people survived a cardiac arrest when first aiders received an app alert

The studySmith CM, Lall R, Fothergill RT, Spaight R, Perkins GD. The effect of the GoodSAM volunteer first-responder app on survival to hospital discharge following out-of-hospital cardiac arrest. Eur Heart J Acute Cardiovasc Care 2022;11:20-31.To read the full NIHR Alert, go to: https://evidence.nihr.ac.uk/alert/more-people-survived-cardiac-arrest-first-aiders-goodsam-alert/.

Contributions of event rates, pre-hospital deaths, and deaths following hospitalisation to variations in myocardial infarction mortality in 326 districts in England: a spatial analysis of linked hospitalisation and mortality data

BACKGROUND

Myocardial infarction mortality varies substantially within high-income countries. There is limited guidance on what interventions-including primary and secondary prevention, or improvement of care pathways and quality-can reduce myocardial infarction mortality. Our aim was to understand the contributions of incidence (event rate), pre-hospital deaths, and hospital case fatality to the variations in myocardial infarction mortality within England.

METHODS

We used linked data from national databases on hospitalisations and deaths with acute myocardial infarction (ICD-10 codes I21 and I22) as a primary hospital diagnosis or underlying cause of death, from Jan 1, 2015, to Dec 31, 2018. We used geographical identifiers to estimate myocardial infarction event rate (number of events per 100 000 population), death rate (number of deaths per 100 000 population), total case fatality (proportion of events that resulted in death), pre-hospital fatality (proportion of events that resulted in pre-hospital death), and hospital case fatality (proportion of admissions due to myocardial infarction that resulted in death within 28 days of admission) for men and women aged 45 years and older across 326 districts in England. Data were analysed in a Bayesian spatial model that accounted for similarities and differences in spatial patterns of fatal and non-fatal myocardial infarction. Age-standardised rates were calculated by weighting age-specific rates by the corresponding national share of the appropriate denominator for each measure.

FINDINGS

From 2015 to 2018, national age-standardised death rates were 63 per 100 000 population in women and 126 per 100 000 in men, and event rates were 233 per 100 000 in women and 512 per 100 000 in men. After age-standardisation, 15·0% of events in women and 16·9% in men resulted in death before hospitalisation, and hospital case fatality was 10·8% in women and 10·6% in men. Across districts, the 99th-to-1st percentile ratio of age-standardised myocardial infarction death rates was 2·63 (95% credible interval 2·45-2·83) in women and 2·56 (2·37-2·76) in men, with death rates highest in parts of northern England. The main contributor to this variation was myocardial infarction event rate, with a 99th-to-1st percentile ratio of 2·55 (2·39-2·72) in women and 2·17 (2·08-2·27) in men across districts. Pre-hospital fatality was greater than hospital case fatality in every district. Pre-hospital fatality had a 99th-to-1st percentile ratio of 1·60 (1·50-1·70) in women and 1·75 (1·66-1·86) in men across districts, and made a greater contribution to variation in total case fatality than did hospital case fatality (99th-to-1st percentile ratio 1·39 [1·29-1·49] and 1·49 [1·39-1·60]). The contribution of case fatality to variation in deaths across districts was largest in women aged 55-64 and 65-74 years and in men aged 55-64, 65-74, and 75-84 years. Pre-hospital fatality was slightly higher in men than in women in most districts and age groups, whereas hospital case fatality was higher in women in virtually all districts at ages up to and including 65-74 years.

INTERPRETATION

Most of the variation in myocardial infarction mortality in England is due to variation in myocardial infarction event rate, with a smaller role for case fatality. Most variation in case fatality occurs before rather than after hospital admission. Reducing subnational variations in myocardial infarction mortality requires interventions that reduce event rate and pre-hospital deaths.

FUNDING

Wellcome Trust, British Heart Foundation, Medical Research Council (UK Research and Innovation), and National Institute for Health Research (UK).

Dispatching citizens as first responders to out-of-hospital cardiac arrests: a systematic review and meta-analysis

Mobile phone technologies to alert citizen first responders to out-of-hospital cardiac arrests (OHCAs) were implemented in numerous countries. This systematic review and meta-analysis aim to investigate whether activating citizen first responders increases bystanders' interventions and improves outcomes. We searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to 24 November 2021, for studies comparing citizen first responders' activation versus standard emergency response in the case of OHCA. The primary outcome was survival at hospital discharge or 30 days. Secondary outcomes were discharge with favourable neurological outcome, bystander-initiated cardiopulmonary resuscitation (CPR), and the use of automated external defibrillators (AEDs) before ambulance arrival. Evidence certainty was evaluated with GRADE. Our search strategy yielded 1215 articles. After screening, we included 10 studies for a total of 23 351 patients. OHCAs for which citizen first responders were activated had higher rates of survival at hospital discharge or 30 days compared with standard emergency response [nine studies; 903/9978 (9.1%) vs. 1104/13 247 (8.3%); odds ratio (OR), 1.45; 95% confidence interval (CI), 1.21-1.74; P < 0.001], return of spontaneous circulation [nine studies; 2575/9169 (28%) vs. 3445/12 607 (27%); OR, 1.40; 95% CI, 1.07-1.81; P = 0.01], bystander-initiated CPR [eight studies; 5876/9074 (65%) vs. 6384/11 970 (53%); OR, 1.75; 95% CI, 1.43-2.15; P < 0.001], and AED use [eight studies; 654/9132 (7.2%) vs. 624/14 848 (4.2%); OR, 1.82; 95% CI, 1.31-2.53; P < 0.001], but similar rates of neurological intact discharge [three studies; 316/2685 (12%) vs. 276/2972 (9.3%); OR, 1.37; 95% CI, 0.81-2.33; P = 0.24]. Alerting citizen first responders to OHCA patients is associated with higher rates of bystander-initiated CPR, use of AED before ambulance arrival, and survival at hospital discharge or 30 days.

Characteristics and motivational factors for joining a lay responder system dispatch to out-of-hospital cardiac arrests

BACKGROUND

There has been in increase in the use of systems for organizing lay responders for suspected out-of-hospital cardiac arrests (OHCAs) dispatch using smartphone-based technology. The purpose is to increase survival rates; however, such systems are dependent on people's commitment to becoming a lay responder. Knowledge about the characteristics of such volunteers and their motivational factors is lacking. Therefore, we explored characteristics and quantified the underlying motivational factors for joining a smartphone-based cardiopulmonary resuscitation (CPR) lay responder system.

METHODS

In this descriptive cross-sectional study, 800 consecutively recruited lay responders in a smartphone-based mobile positioning first-responder system (SMS-lifesavers) were surveyed. Data on characteristics and motivational factors were collected, the latter through a modified version of the validated survey "Volunteer Motivation Inventory" (VMI). The statements in the VMI, ranked on a Likert scale (1-5), corresponded to(a) intrinsic (an inner belief of doing good for others) or (b) extrinsic (earning some kind of reward from the act) motivational factors.

RESULTS

A total of 461 participants were included in the final analysis. Among respondents, 59% were women, 48% between 25 and 39 years of age, 37% worked within health care, and 66% had undergone post-secondary school. The most common way (44%) to learn about the lay responder system was from a CPR instructor. A majority (77%) had undergone CPR training at their workplace. In terms of motivation, where higher scores reflect greater importance to the participant, intrinsic factors scored highest, represented by the category values (mean 3.97) followed by extrinsic categories reciprocity (mean 3.88) and self-esteem (mean 3.22).

CONCLUSION

This study indicates that motivation to join a first responder system mainly depends on intrinsic factors, i.e. an inner belief of doing good, but there are also extrinsic factors, such as earning some kind of reward from the act, to consider. Focusing information campaigns on intrinsic factors may be the most important factor for successful recruitment. When implementing a smartphone-based lay responder system, CPR instructors, as a main information source to potential lay responders, as well as the workplace, are crucial for successful recruitment.

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

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

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

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

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

INTRODUCTION

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

The effect of the GoodSAM volunteer first-responder app on survival to hospital discharge following out-of-hospital cardiac arrest

AIMS

Bystander cardiopulmonary resuscitation and defibrillation can double survival to hospital discharge in out-of-hospital cardiac arrest. Mobile phone applications, such as GoodSAM, alerting nearby volunteer first-responders about out-of-hospital cardiac arrest could potentially improve bystander cardiopulmonary resuscitation and defibrillation, leading to better patient outcomes. The aim of this study was to determine GoodSAM's effect on survival to hospital discharge following out-of-hospital cardiac arrest.

METHODS AND RESULTS

We collected data from the Out-of-Hospital Cardiac Arrest Outcomes Registry (University of Warwick, UK) submitted by the London Ambulance Service (1 April 2016 to 31 March 2017) and East Midlands Ambulance Service (1 January 2018 to 17 June 2018) and matched out-of-hospital cardiac arrests to GoodSAM alerts. We constructed logistic regression models to determine if there was an association between a GoodSAM first-responder accepting an alert and survival to hospital discharge, adjusting for location type, presenting rhythm, age, gender, ambulance service response time, cardiac arrest witnessed status, and bystander actions. Survival to hospital discharge was 9.6% (393/4196) in London and 7.2% (72/1001) in East Midlands. A GoodSAM first-responder accepted an alert for out-of-hospital cardiac arrest in 1.3% (53/4196) cases in London and 5.4% (51/1001) cases in East Midlands. When a responder accepted an alert, the adjusted odds ratio for survival to hospital discharge was 3.15 (95% CI: 1.19-8.36, P = 0.021) in London and 3.19 (95% CI: 1.17-8.73, P = 0.024) in East Midlands.

CONCLUSION

Alert acceptance was associated with improved survival in both ambulance services. Alert acceptance rates were low, and challenges remain to maximize the potential benefit of GoodSAM.

Responding to Cardiac Arrest in the Community in the Digital Age

Sudden cardiac arrest (SCA) is a common event, affecting almost 400,000 individuals annually in North America. Initiation of cardiopulmonary resuscitation (CPR) and early defibrillation using an automated external defibrillator (AED) are critical for survival, yet many bystanders are reluctant to intervene. Digital technologies, including mobile devices, social media and crowdsourcing may help play a role to improve survival from SCA. In this article we review the current digital tools and strategies available to increase rates of bystander recognition of SCA, prompt immediate activation of Emergency Medical Services (EMS), initiate high quality CPR and to locate, retrieve and operate AEDs. Smartphones can help to both educate and connect bystanders with EMS dispatchers, through text messaging or video-calling, to encourage the initiation of CPR and retrieval of the closest AED. Wearable devices and household smartspeakers could play a future role in continuous vital signs monitoring in individuals at-risk of lethal arrhythmias and send an alert to either chosen contacts or EMS. Machine learning algorithms and mathematical modeling may aid EMS dispatchers with better recognition of SCA as well as policymakers with where to best place AEDs for optimal accessibility. There are challenges with the use of digital tech, including the need for government regulation and issues with data ownership, accessibility and interoperability. Future research will include smart cities, e-linkages, new technologies and using social media for mass education. Together or in combination, these emerging digital technologies may represent the next leap forward in SCA survival.

Calculating real-world travel routes instead of straight-line distance in the community response to out-of-hospital cardiac arrest

•

In out-of-hospital cardiac arrest, straight-line distance estimates substantially underestimated actual travel distance for bystanders retrieving a nearby public-access AED and for volunteer first-responders travelling to the scene.

•

Using real-world travel estimates changed the identity of the nearest public-access AED in more than a quarter of out-of-hospital cardiac arrests.

Background

Using straight-line distance to estimate the proximity of public-access Automated External Defibrillators (AEDs) or volunteer first-responders to potential out-of-hospital cardiac arrests (OHCAs) does not reflect real-world travel distance. The difference between estimates may be an important consideration for bystanders and first-responders responding to OHCAs and may potentially impact patient outcome.

Objectives

To explore how calculating real-world travel routes instead of using straight-line distance estimates might impact the community response to OHCA.

Methods

We mapped 4355 OHCA (01/04/2016-31/03/2017) and 2677 AEDs in London (UK), and 1263 OHCA (18/06/2017-17/06/2018) and 4704 AEDs in East Midlands (UK) using ArcGIS mapping software. We determined the distance from OHCAs to the nearest AED using straight-line estimates and real-world travel routes. We mapped locations of potential OHCAs (London: n = 9065, 20/09/2019-22/03/2020; East Midlands: n = 7637, 20/09/2019-17/03/2020) for which volunteer first-responders were alerted by the GoodSAM mobile-phone app, and calculated response distance using straight-line estimates and real-world travel routes. We created Receiver Operating Characteristic (ROC) curves and calculated the Area Under the Curve (AUC) to determine if travel distance predicted whether or not a responder accepted an alert.

Results

Real-world travel routes to the nearest AED were (median) 219 m longer (623 m vs 406 m) than straight-line estimates in London, and 211 m longer (568 m vs 357 m) in East Midlands. The identity of the nearest AED changed on 26% occasions in both areas when calculating real-world travel routes. GoodSAM responders’ real-world travel routes were (median) 222 m longer (601 m vs 379 m) in London, and 291 m longer (814 m vs 523 m) in East Midlands. AUC statistics for both areas demonstrated that neither straight-line nor real-world travel distance predicted whether or not a responder accepted an alert.

Conclusions

Calculating real-world travel routes increases the estimated travel distance and time for those responding to OHCAs. Calculating straight-line distance may overestimate the benefit of the community response to OHCA.

Wellbeing, emotional response and stress among lay responders dispatched to suspected out-of-hospital cardiac arrests

BACKGROUND

Systems for smartphone dispatch of lay responders to perform cardio-pulmonary resuscitation (CPR) and bring automated external defibrillators to out-of-hospital cardiac arrests (OHCAs) are advocated by recent international guidelines and emerging worldwide.

OBJECTIVES

This study aimed to investigate the emotional responses, posttraumatic stress reactions and levels of wellbeing among smartphone-alerted lay responders dispatched to suspected OHCAs.

METHODS

Lay responders were stratified by level of exposure: unexposed (Exp-0), tried to reach (Exp-1), and reached the suspected OHCA (Exp-2). Participants rated their emotional responses online, at 90 minutes and at 4-6 weeks after an incident. Level of emotional response was measured in two dimensions of core affect: "alertness" - from deactivation to activation, and "pleasantness" - from unpleasant to pleasant. At 4-6 weeks, WHO wellbeing index and level of posttraumatic stress (PTSD) were also rated.

RESULTS

Altogether, 915 (28%) unexposed and 1471 (64%) exposed responders completed the survey. Alertness was elevated in the exposed groups: Exp-0: 6.7 vs. Exp-1: 7.3 and Exp-2: 7.5, (p < 0.001) and pleasantness was highest in the unexposed group: 6.5, vs. Exp-1: 6.3, and Exp-2: 6.1, (p < 0.001). Mean scores for PTSD at follow-up was below clinical cut-off, Exp-0: 9.9, Exp-1: 8.9 and Exp-2: 8.8 (p = 0.065). Wellbeing index showed no differences, Exp-0: 78.0, Exp-1: 78.5 and Exp-2: 79.9 (p = 0.596).

CONCLUSION

Smartphone dispatched lay responders rated the experience as high-energy and mainly positive. No harm to the lay responders was seen. The exposed groups had low posttraumatic stress scores and high-level general wellbeing at follow-up.

A binational survey of smartphone activated volunteer responders for out-of-hospital cardiac arrest: Availability, interventions, and post-traumatic stress

BACKGROUND

Responder smartphone apps use global positioning data to enable emergency medical services to alert volunteer responders of nearby potential out-of-hospital cardiac arrests (OHCA).

AIM

To assess volunteer availability, interventions provided and frequency of probable post traumatic stress disorder (PTSD) experienced by responders receiving a smartphone alert.

METHODS

A web-based survey was emailed to alerted responders at week-two post-alert and a PTSD screening survey at week-six, in Victoria, Australia (1/08/2019-8/11/2020), and in New Zealand (18/02/2020-28/10/2020).

RESULTS

We received 1,985 responses to the week-two survey and 1,443 responses to the week-six survey. Of the 1,985 responders, 1,744 (87.9%) had completed cardiopulmonary resuscitation (CPR) training in the last twelve months, and 1,514 (76.3%) had performed CPR at least once. The alert was seen by 1,501 (75.6%) responders, 749 (37.7%) accepted the alert, 538 (27.1%) arrived on scene, and 283 (14.3%) provided care to the patient. In the multivariable analysis, CPR training within twelve months was associated with increased odds of responders accepting alerts (AOR 1.41, 95%CI: 1.02-1.96; p=0.040). Responders who had performed CPR before, were more than twice as likely to provide patient care compared to responders who had not (AOR 2.54, 95%CI: 1.56-4.12; p<0.001). One responder screened positive for probable PTSD.

CONCLUSION

Acceptance rates in Australia and New Zealand were consistent with other smartphone apps. Responder recruitment should be targeted at those with medical backgrounds who have prior CPR experience, as they are more likely to provide care. The very low risk of PTSD is reassuring information when recruiting volunteers.

Cardiac Arrest Occurring in High-Rise Buildings: A Scoping Review

Out-of-hospital cardiac arrests (OHCAs) occurring in high-rise buildings are a challenge to Emergency Medical Services (EMS). Contemporary EMS guidelines lack specific recommendations for systems and practitioners regarding the approach to these patients. This scoping review aimed to map the body of literature pertaining to OHCAs in high-rise settings in order to clarify concepts and understanding and to identify knowledge gaps. Databases were searched from inception through to 6 May 2021 including OVID Medline, PubMed, Embase, CINAHL, and Scopus. Twenty-three articles were reviewed, comprising 8 manikin trials, 14 observational studies, and 1 mathematical modelling study. High-rise settings commonly have lower availability of bystanders and automatic external defibrillators (AEDs), while height constraints often lead to delays in EMS interventions and suboptimal cardiopulmonary resuscitation (CPR), scene access, and extrication. Four studies found return of spontaneous circulation (ROSC) rates to be significantly poorer, while seven studies found rates of survival-to-hospital discharge (n = 3) and neurologically favourable survival (n = 4) to be significantly lower in multistorey settings. Mechanical chest compression devices, transfer sheets, and strategic defibrillator placement were suggested as approaches to high-rise OHCA management. A shift to maximising on-scene treatment time, along with bundling novel prehospital interventions, could ameliorate some of these difficulties and improve clinical outcomes for patients.

Fifth Generation Cellular Networks and Neurosurgery: A Narrative Review

Connectivity is a driving force for productivity across a wide variety of sectors in the 21st century, with health care being no exception. Fifth generation cellular technology (5G) is frequently alluded to in the mainstream media but understanding of the technology and its potential impact is not widespread in clinical communities. It promises unprecedented improvement in speed, bandwidth, reliability, and latency, all of which have significant implications for the way we use wireless data. 5G can be subdivided into 3 parallel technological architectures: extended mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), and massive machine type communication (mMTC). These domains each present different and exciting prospects for the future of health care. This narrative review aims to elucidate the nature of 5G, its context within the development of telecommunications, and describe some of the notable opportunities it presents to the neurosurgical community. In many cases the requisite hardware has already been developed, but use has been limited by the requirements of a fast, reliable, and omnipresent network connection. Examples include telesurgical robots, remote supervision of procedures, integrated smart operating rooms, and clinician telepresence. The events of 2020 and the COVID-19 pandemic have brought the world's attention to digital transformation. The mechanics of 5G connectivity creates the capacity for these changes to be applied practically. An understanding of this technology is essential to appreciate the development and opportunities which will be part of our professional future.

A review on initiatives for the management of daily medical emergencies prior to the arrival of emergency medical services

Emergency services worldwide face increasing cost pressure that potentially limits their existing resources. In many countries, emergency services also face the issues of staff shortage-creating extra challenges and constraints, especially during crisis times such as the COVID-19 pandemic-as well as long distances to sparsely populated areas resulting in longer response times. To overcome these issues and potentially reduce consequences of daily (medical) emergencies, several countries, such as Sweden, Germany, and the Netherlands, have started initiatives using new types of human resources as well as equipment, which have not been part of the existing emergency systems before. These resources are employed in response to medical emergency cases if they can arrive earlier than emergency medical services (EMS). A good number of studies have investigated the use of these new types of resources in EMS systems, from medical, technical, and logistical perspectives as their study domains. Several review papers in the literature exist that focus on one or several of these new types of resources. However, to the best of our knowledge, no review paper that comprehensively considers all new types of resources in emergency medical response systems exists. We try to fill this gap by presenting a broad literature review of the studies focused on the different new types of resources, which are used prior to the arrival of EMS. Our objective is to present an application-based and methodological overview of these papers, to provide insights to this important field and to bring it to the attention of researchers as well as emergency managers and administrators.

Live video from bystanders' smartphones to improve cardiopulmonary resuscitation

AIM

To investigate whether live video streaming from the bystander's smartphone to a medical dispatcher can improve the quality of bystander cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest (OHCA).

METHODS

After CPR was initiated, live video was added to the communication by the medical dispatcher using smartphone technology. From the video recordings, we subjectively evaluated changes in CPR quality after themedical dispatcher had used live video to dispatcher-assisted CPR (DA-CPR). CPR quality was registered for each bystander and compared with CPR quality after video-instructed DA-CPR. Data were analysed using logistic regression adjusted for bystander's relation to the patient and whether the arrest was witnessed.

RESULTS

CPR was provided with live video streaming in 52 OHCA calls, with 90 bystanders who performed chest compressions. Hand position was incorrect for 38 bystanders (42.2%) and improved for 23 bystanders (60.5%) after video-instructed DA-CPR. The compression rate was incorrect for 36 bystanders (40.0%) and improved for 27 bystanders (75.0%). Compression depth was incorrect for 57 bystanders (63.3%) and improved for 33 bystanders (57.9%). The adjusted odds ratios for improved CPR after video-instructed DA-CPR were; hand position 5.8 (95% CI: 2.8-12.1), compression rate 7.7 (95% CI: 3.4-17.3), and compression depth 7.1 (95% CI: 3.9-12.9). Hands-off time was reduced for 34 (37.8%) bystanders.

CONCLUSIONS

Live video streaming from the scene of a cardiac arrest to medical dispatchers is feasible. It allowed an opportunity for dispatchers to coach those providing CPR which was associated with a subjectively evaluated improvement in CPR performance.

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.

[Ethics of resuscitation and end of life decisions]

These European Resuscitation Council Ethics guidelines provide evidence-based recommendations for the ethical, routine practice of resuscitation and end-of-life care of adults and children. The guideline primarily focus on major ethical practice interventions (i.e. advance directives, advance care planning, and shared decision making), decision making regarding resuscitation, education, and research. These areas are tightly related to the application of the principles of bioethics in the practice of resuscitation and end-of-life care.

European Resuscitation Council Guidelines 2021: Ethics of resuscitation and end of life decisions

These European Resuscitation Council Ethics guidelines provide evidence-based recommendations for the ethical, routine practice of resuscitation and end-of-life care of adults and children. The guideline primarily focus on major ethical practice interventions (i.e. advance directives, advance care planning, and shared decision making), decision making regarding resuscitation, education, and research. These areas are tightly related to the application of the principles of bioethics in the practice of resuscitation and end-of-life care.

Use of Public Automated External Defibrillators in Out-of-Hospital Cardiac Arrest in Poland

Background and objectives: National medical records indicate that approximately 350,000–700,000 people die each year from sudden cardiac arrest. The guidelines of the European Resuscitation Council (ERC) and the International Liaison Committee on Resuscitation (ILCOR) indicate that in addition to resuscitation, it is important—in the case of so-called defibrillation rhythms—to perform defibrillation as quickly as possible. The aim of this study was to assess the use of public automated external defibrillators in out of hospital cardiac arrest in Poland between 2008 and 2018. Materials and Methods: One hundred and twenty cases of use of an automated external defibrillator placed in a public space between 2008 and 2018 were analyzed. The study material consisted of data on cases of use of an automated external defibrillator in adults (over 18 years of age). Only cases of automated external defibrillators (AED) use in a public place other than a medical facility were analysed, additionally excluding emergency services, i.e., the State Fire Service and the Volunteer Fire Service, which have an AED as part of their emergency equipment. The survey questionnaire was sent electronically to 1165 sites with AEDs and AED manufacturers. A total of 298 relevant feedback responses were received. Results: The analysis yielded data on 120 cases of AED use in a public place. Conclusions: Since 2016, there has been a noticeable increase in the frequency of use of AEDs located in public spaces. This is most likely related to the spread of public access to defibrillation and increased public awareness.

Smartphone-based dispatch of community first responders to out-of-hospital cardiac arrest - statements from an international consensus conference

Background

Over the past decade Smartphone-based activation (SBA) of Community First Responders (CFR) to out-of-hospital cardiac arrests (OHCA) has gained much attention and popularity throughout Europe. Various programmes have been established, and interestingly there are considerable differences in technology, responder spectrum and the degree of integration into the prehospital emergency services. It is unclear whether these dissimilarities affect outcome. This paper reviews the current state in five European countries, reveals similarities and controversies, and presents consensus statements generated in an international conference with the intention to support public decision making on future strategies for SBA of CFR.

Methods

In a consensus conference a three-step approach was used: (i) presentation of current research from five European countries; (ii) workshops discussing evidence amongst the audience to generate consensus statements; (iii) anonymous real-time voting applying the modified RAND-UCLA Appropriateness method to adopt or reject the statements. The consensus panel aimed to represent all stakeholders involved in this topic.

Results

While 21 of 25 generated statements gained approval, consensus was only found for 5 of them. One statement was rejected but without consensus. Members of the consensus conference confirmed that CFR save lives. They further acknowledged the crucial role of emergency medical control centres and called for nationwide strategies.

Conclusions

Members of the consensus conference acknowledged that smartphone-based activation of CFR to OHCA saves lives. The statements generated by the consensus conference may assist the public, healthcare services and governments to utilise these systems to their full potential, and direct the research community towards fields that still need to be addressed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-021-00841-1.

Smartphone Activation of Citizen Responders to Facilitate Defibrillation in Out-of-Hospital Cardiac Arrest

BACKGROUND

Dispatching citizen responders through a smartphone application (app) holds the potential to increase bystander cardiopulmonary resuscitation (CPR) and defibrillation in out-of-hospital cardiac arrest (OHCA).

OBJECTIVES

This study investigated arrival at the OHCA location of app-dispatched citizen responders before the Emergency Medical Services (EMS) and the association with bystander CPR and bystander defibrillation.

METHODS

Suspected OHCAs with alerted citizen responders from September 1, 2017, to August 31, 2018, were included. Citizen responders located 1.8 km (1.1 miles) from the OHCA were dispatched to start CPR or retrieve an automated external defibrillator. OHCAs where at least 1 citizen responder arrived before EMS were compared with OHCAs where EMS arrived first. In both groups, random bystanders could be present before the arrival of citizen responders and the EMS. Primary outcomes were bystander CPR and bystander defibrillation, which included CPR and defibrillation by citizen responders and random bystanders.

RESULTS

Citizen responders were alerted in 819 suspected OHCAs, of which 438 (53.5%) were confirmed cardiac arrests eligible for inclusion. At least 1 citizen responder arrived before EMS in 42.0% (n = 184) of all included OHCAs. When citizen responders arrived before EMS, the odds for bystander CPR increased (odds ratio: 1.76; 95% confidence interval: 1.07 to 2.91; p = 0.027) and the odds for bystander defibrillation more than tripled (odds ratio: 3.73; 95% confidence interval: 2.04 to 6.84; p < 0.001) compared with OHCAs in which citizen responders arrived after EMS.

CONCLUSIONS

Arrival of app-dispatched citizen responders before EMS was associated with increased odds for bystander CPR and a more than 3-fold increase in odds for bystander defibrillation. (The HeartRunner Trial; NCT03835403).

Out-of-Hospital Cardiac Arrest in London during the COVID-19 pandemic

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We compared OHCA presentations in London during March and April 2019 and 2020

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There was an 81% increase in OHCAs during the first peak of the COVID-19 pandemic

•

This increase was closely related to SARS-CoV-2 infection rates in London

•

We report an increase in the rate of bystander CPR in London during the pandemic

•

Outcomes following OHCA were significantly poorer during the COVID-19 pandemic

Aim

There is an emerging potential link between the COVID-19 pandemic and incidence and outcomes from out-of-hospital cardiac arrest (OHCA). We aimed to describe the incidence, characteristics and outcomes from OHCA in London, UK during the first wave of the pandemic.

Methods

We examined data for all OHCA patients attended by the London Ambulance Service from 1st March to 30th April 2020 and compared our findings to the previous year. We also compared OHCA characteristics and short-term outcomes for those suspected or confirmed to have COVID-19 with those who were not. Additionally, we investigated the relationship between daily COVID-19 cases and OHCA incidents.

Results

We observed an 81% increase in OHCAs during the pandemic, and a strong correlation between the daily number of COVID-19 cases and OHCA incidents (r = 0.828, p < 0.001). We report an increase in OHCA occurring in a private location (92.9% vs 85.5%, p < 0.001) and an increased bystander CPR (63.3% vs 52.6%, p < 0.001) during the pandemic, as well as fewer resuscitation attempts (36.4% vs 39.6%, p = 0.03) and longer EMS response times (9.3 vs 7.2 min, p < 0.001). Survival at 30 days post-arrest was poorer during the pandemic (4.4% vs 10.6%, p < 0.001) and amongst patients where COVID-19 was considered likely (1.0% vs 6.3%, p < 0.001).

Conclusions

During the first wave of the COVID-19 pandemic in London, we saw a dramatic rise in the incidence of OHCA, accompanied by a significant reduction in survival. The pattern of increased incidence and mortality closely reflected the rise in confirmed COVID-19 infections in the city.

Crowdsourcing to save lives: A scoping review of bystander alert technologies for out-of-hospital cardiac arrest

AIM

Out-of-hospital cardiac arrest (OHCA) constitutes a significant global health burden, with a survival rate of only 10-12%. Mobile phone technologies have been developed that crowdsource citizen volunteers to nearby OHCAs in order to initiate resuscitation prior to ambulance arrival. We performed a scoping review to map the available literature on these crowdsourcing technologies and compared their technical specifications.

METHODS

A search strategy was developed for five online databases. Two reviewers independently assessed all articles for inclusion and extracted relevant study information. Subsequently, we performed a supplementary internet search and consulted experts to identify all available bystander alert technologies and their specifications.

RESULTS

We included 65 articles examining bystander alerting technologies from more than 15 countries. We also identified 25 unique technologies, of which 18 were described in the included literature. Technologies were text message-based systems (n = 3) or mobile phone applications (n = 22). Most (21/25) used global positioning systems to direct bystanders to victims and nearby AEDs. Response radii for alerts varied widely from 200 m to 10 km. Some technologies incorporated advanced features such as video-conferencing with ambulance dispatch and detailed alert settings. Not all systems required volunteers to have training in cardiopulmonary resuscitation. Only ten studies assessed impact on clinical outcomes. Key barriers discussed included false positive alerts, legal liability, and potential psychological impact on volunteers.

CONCLUSION

Our review provides a comprehensive overview of crowdsourcing technologies for bystander intervention in out-of-hospital cardiac arrest. Future work should focus on clinical outcomes and methods of addressing barriers to implementation.

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.

Mobile Smartphone Technology Is Associated With Out-of-hospital Cardiac Arrest Survival Improvement: The First Year "Greater Paris Fire Brigade" Experience

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) remains associated with very high mortality. Accelerating the initiation of efficient cardiopulmonary resuscitation (CPR) is widely perceived as key to improving outcomes. The main goal was to determine whether identification and activation of nearby first responders through a smartphone application named Staying Alive (SA) can improve survival following OHCA in a large urban area (Paris).

METHODS

We conducted a nonrandomized cohort study of all adults with OHCA managed by the Greater Paris Fire Brigade during 2018, irrespective of mobile application usage. We compared survival data in cases where SA did or did not lead to the activation of nearby first responders. During dispatch, calls for OHCA were managed with or without SA. The intervention group included all cases where nearby first responders were successfully identified by SA and actively contributed to CPR. The control group included all other cases. We compared survival at hospital discharge between the intervention and control groups. We analyzed patient data, CPR metrics, and first responders' characteristics.

RESULTS

Approximately 4,107 OHCA cases were recorded in 2018. Among those, 320 patients were in the control group, whereas 46 patients, in the intervention group, received first responder-initiated CPR. After adjustment for confounders, survival at hospital discharge was significantly improved for patients in the intervention group (35% vs. 16%, adjusted odds ratio = 5.9, 95% confidence interval = 2.1 to 16.5, p < 0.001). All CPR metrics were improved in the intervention group.

CONCLUSIONS

We report that mobile smartphone technology was associated with OHCA survival through accelerated initiation of efficient CPR by first responders in a large urban area.

Effect of Optimized Versus Guidelines-Based Automated External Defibrillator Placement on Out-of-Hospital Cardiac Arrest Coverage: An In Silico Trial

Background

Mathematical optimization of automated external defibrillator (AED) placement may improve AED accessibility and out‐of‐hospital cardiac arrest (OHCA) outcomes compared with American Heart Association (AHA) and European Resuscitation Council (ERC) placement guidelines. We conducted an in silico trial (simulated prospective cohort study) comparing mathematically optimized placements with placements derived from current AHA and ERC guidelines, which recommend placement in locations where OHCAs are usually witnessed.

Methods and Results

We identified all public OHCAs of presumed cardiac cause from 2008 to 2016 in Copenhagen, Denmark. For the control, we computationally simulated placing 24/7‐accessible AEDs at every unique, public, witnessed OHCA location at monthly intervals over the study period. The intervention consisted of an equal number of simulated AEDs placements, deployed monthly, at mathematically optimized locations, using a model that analyzed historical OHCAs before that month. For each approach, we calculated the number of OHCAs in the study period that occurred within a 100‐m route distance based on Copenhagen’s road network of an available AED after it was placed (“OHCA coverage”). Estimated impact on bystander defibrillation and 30‐day survival was calculated by multivariate logistic regression. The control scenario involved 393 AEDs at historical, public, witnessed OHCA locations, covering 15.8% of the 653 public OHCAs from 2008 to 2016. The optimized locations provided significantly higher coverage (24.2%; P<0.001). Estimated bystander defibrillation and 30‐day survival rates increased from 15.6% to 18.2% (P<0.05) and from 32.6% to 34.0% (P<0.05), respectively. As a baseline, the 1573 real AEDs in Copenhagen covered 14.4% of the OHCAs.

Conclusions

Mathematical optimization can significantly improve OHCA coverage and estimated clinical outcomes compared with a guidelines‐based approach to AED placement.

Development of a Novel Framework to Propose New Strategies for Automated External Defibrillators Deployment Targeting Residential Out-Of-Hospital Cardiac Arrests: Application to the City of Milan

Public Access Defibrillation (PAD) is the leading strategy in reducing time to first defibrillation in cases of Out-Of-Hospital Cardiac Arrest (OHCA), but PAD programs are underperforming considering their potentiality. Our aim was to develop an analysis and optimization framework, exploiting georeferenced information processed with Geographic Information Systems (GISs), specifically targeting residential OHCAs. The framework, based on an historical database of OHCAs, location of Automated External Defibrillators (AEDs), topographic and demographic information, proposes new strategies for AED deployment focusing on residential OHCAs, where performance assessment was evaluated using AEDs “catchment area” (area that can be reached within 6 min walk along streets). The proposed framework was applied to the city of Milan, Lombardy (Italy), considering the OHCA database of four years (2015–2018), including 8152 OHCA, of which 7179 (88.06%) occurred in residential locations. The proposed strategy for AEDs deployment resulted more effective compared to the existing distribution, with a significant improvement (from 41.77% to 73.33%) in OHCAs’ spatial coverage. Further improvements were simulated with different cost scenarios, resulting in more cost-efficient solutions. Results suggest that PAD programs, either in brand-new territories or in further improvements, could significantly benefit from a comprehensive planning, based on mathematical models for risk mapping and on geographical tools.

myResponder Smartphone Application to Crowdsource Basic Life Support for Out-of-Hospital Cardiac Arrest: The Singapore Experience

OBJECTIVE

The Singapore myResponder is a novel smartphone application developed by the Singapore Civil Defence Force (SCDF) that notifies volunteer first responders of a suspected out-of-hospital cardiac arrest (OHCA) case and locations of Automated External Defibrillators (AED) in the vicinity so that they can assist with resuscitation. We aimed to examine the performance of this application, challenges encountered, and future directions. Methods: We analyzed data from the myResponder app since its launch from April 2015 to July 2019. The number of installations, registered community first responders, suspected OHCA cases, notifications sent by the app, percentage of responders who accepted activation and arrived at scene were reviewed. A subgroup of taxi driving responders (within a 1.5-kilometer response radius) carrying an AED under a subsequent pilot program was also analyzed. Results: By July 2019, 46,689 responders were registered in the myResponder app. There were a total of 19,189 cases created for suspected OHCA, with a median of 358 cases per month (IQR 330-430), in which 10,073 responders accepted activation from myResponder and 4,955 arrived on-scene. A total of 135,599 notifications were sent for these cases, with a median of 7.1 notifications per case (IQR 4.3-8.7). In 2019, the percentages of responders who accepted notification and arrived on scene were 45.8% and 24.1%, respectively. 43% (1110/2581) of responders arrived before EMS crew. Conclusion: The myResponder mobile application is a feasible smart technology solution to improve community response to OHCA, and to increase bystander CPR and AED use. Future directions include increasing the number of active responders, improving response rates, app performance, and better data capture for quality improvement.

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.

Championing survival: connecting the unknown network of responders to address out-of-hospital cardiac arrest

Early intervention for out-of-hospital cardiac arrest (OHCA) presents a challenge for Emergency Medical Services (EMS) across Europe. Strategies designed to address this include education and training initiatives for citizens and building CPR skills capacity and awareness amongst health care professionals. However, there is a need to improve access to volunteer first responders who can commence CPR and defibrillate before the arrival of EMS. In the UK, initiatives such GoodSAM have integrated crowdsourcing technology with ambulance services to allow them autonomy in alerting responders to OHCAs which is parallel to an EMS dispatch. These services are building capacity to improve the initial 'call for help' and time to commence CPR and defibrillation if indicated. The next step is to identify and implement appropriate methods for public engagement, involvement and eventual networking of resources with statutory bodies such as local EMS. As crowdsourcing volunteer responders is at an early stage, there is a need to determine whether crowdsourcing is associated with patient outcomes, what its impact is on those responding to OHCA, whether it facilitates or impedes current services, and whether it is a safe and cost effective way to involve citizens to intervene in the community during cardiac arrest or other medical emergencies? Addressing such issues is likely to provide further insight into the role and effectiveness of new technologies and their potential impact on the wider community.

Motivation of emergency medical services volunteers: a study of organized Good Samaritans

BACKGROUND

Early professional care in emergencies is beneficial in general and its utility has been proven in many studies, particularly in regard to out-of-hospital cardiopulmonary arrest. A person in distress can expect help from two sources: bystanders, including family members, community members, and complete strangers; and professionals, including emergency medical services, first responders, firefighters, and police officers. Emergency Medical Services try to achieve faster first response times through various approaches. Recent technological and social developments have enabled a new form of Emergency Medical Services volunteering, called Organized Good Samaritans, which represents a new layer between occasional volunteers and time-donation volunteers. Organized Good Samaritans are people with a medical background, particularly off-duty medical professionals who are willing and able to provide first aid in emergencies in their vicinity.

METHODS

A qualitative formalization of technology-enabled Organized Good Samaritans is presented. One thousand eight hundred Israeli National Emergency Medical Services volunteers were surveyed using Clary and Snyder's Volunteer Functions Inventory instrument. Demographics, professional backgrounds, and volunteering functions of Time-Donation Volunteers and Organized Good Samaritans are compared.

RESULTS

Significant differences between Organized Good Samaritans and Time Donation Volunteers were found. Demographically, Organized Good Samaritans are older and the percentage of males is higher. Professionally, the percentage of physicians and nurses among Organized Good Samaritans is higher. Motivation measures find that the motivation of Organized Good Samaritans is higher and the order of importance of the volunteering functions differs.

CONCLUSION

A clearly identifiable and differently motivated class of emergency services volunteers has emerged. An appropriate information technology infrastructure enables Emergency Medical Services organizations to integrate Organized Good Samaritans into core business processes to shorten response times to emergencies. Organized Good Samaritans provide a volunteering opportunity for highly skilled people unable to be Time-Donation Volunteers. Our findings provide an empirical basis for further research on Organized Good Samaritans integration into Emergency Medical Services operations. Emergency Medical Services administrators can use these findings to establish an Organized Good Samaritans infrastructure and adjust recruitment and retention. This study is limited to one national Emergency Medical Services organization in Israel. Cultural differences can impact results in other countries. Organized Good Samaritans effectiveness should also be studied in terms of response times and medical outcomes.

Place-provider-matrix of bystander cardiopulmonary resuscitation and outcomes of out-of-hospital cardiac arrest: A nationwide observational cross-sectional analysis

AIMS

This study aims to test the association between the place-provider-matrix (PPM) of bystander cardiopulmonary resuscitation (CPR) and outcomes of out-of-hospital cardiac arrest (OHCA).

METHODS

Adult patients with OHCA with a cardiac etiology from 2012 to 2017 in Korea were analyzed, excluding patients who had unknown information on place, type of bystander, or outcome. The PPM was categorized into six groups by two types of places (public versus home) and three types of providers (trained responder (TR), family bystander, and layperson bystander). Outcomes were survival to discharge and good cerebral performance category (CPC) of 1 or 2. Multivariable logistic regression analysis was performed to test the association between PPM group and outcomes with adjustment for potential confounders to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs) (reference = Public-TR).

RESULTS

A total of 73,057 patients were analyzed and were categorized into Public-TR (0.6%), Home-TR (0.3%), Public-Family (1.8%), Home-Family (79.8%), Public-Layperson (9.9%), and Home-Layperson (7.6%) groups. Compared with the Public-TR group, the AORs (95% CIs) for survival to discharge were 0.61 (0.35-1.05) in the Home-TR group, 0.85 (0.62-1.17) in the Public-Family group, 0.38 (0.29-0.50) in the Home-Family group, 1.12 (0.85-1.49) in the Public-Layperson group, and 0.42 (0.31-0.57) in the Home-Layperson group. The AORs (95% CIs) for good CPC were 0.58 (0.27-1.25) in the Home-TR group, 0.88 (0.61-1.27) in the Public-Family group, 0.38 (0.28-0.52) in the Home-Family group, 1.20 (0.87-1.65) in the Public-Layperson group, and 0.42 (0.30-0.59) in the Home-Layperson group.

CONCLUSION

The OHCA outcomes of the Home-Family and Home-Layperson groups were worse than those of the Public-TR group. This finding suggests that OHCA occurring in private places with family or layperson bystanders requires a new strategy, such as dispatching trained responders to the scene to improve CPR outcomes.

Enhancing citizens response to out-of-hospital cardiac arrest: A systematic review of mobile-phone systems to alert citizens as first responders

Introduction

Involving laypersons in response to out-of-hospital cardiac arrest through mobile-phone technology is becoming widespread in numerous countries, and different solutions were developed. We performed a systematic review on the impact of alerting citizens as first responders and to provide an overview of different strategies and technologies used.

Methods

We searched electronic databases up to October 2019. Eligible studies described systems to alert citizens first responders to out-of-hospital cardiac arrest through text messages or apps. We analyzed the implementation and performance of these systems and their impact on patients’ outcomes.

Results

We included 28 manuscripts describing 12 different systems. The first text message system was implemented in 2006 and the first app in 2010. First responders accepted to intervene in median (interquartile) 28.7% (27–29%) of alerts and reached the scene after 4.6 (4.4–5.5) minutes for performing CPR. First responders arrived before ambulance, started CPR and attached a defibrillator in 47% (34–58%), 24% (23–27%) and 9% (6–14%) of cases, respectively. Pooled analysis showed that first responders activation increased layperson-CPR rates (1463/2292 [63.8%] in the intervention group vs. 1094/1989 [55.0%] in the control group; OR = 1.70; 95% CI, 1.11–2.60; p = 0.01) and survival to hospital discharge or at 30 days (327/2273 [14.4%] vs. 184/1955 [9.4%]; OR = 1.51; 95% CI, 1.24–1.84; p < 0.001).

Conclusions

Alerting citizens as first responders in case of out-of-hospital cardiac arrest may reduce the intervention-free time and improve patients’ outcomes.

The impact of bystander relation and medical training on out-of-hospital cardiac arrest outcomes

AIM

In this study, we investigate the impact of bystander relation and medical training on survival to hospital discharge in out-of-hospital cardiac arrest (OHCA) patients receiving bystander cardiopulmonary resuscitation (CPR).

METHODS

A retrospective analysis was performed on non-traumatic OHCA patients receiving bystander CPR and Emergency Medical Service (EMS) attempted resuscitation from 2015 through 2017. Adjusted logistic regression was used to assess the association between related versus unrelated and layperson versus medically trained bystander CPR providers and survival to hospital discharge.

RESULTS

A total of 4464 OHCA were eligible for inclusion, of which 2385 (53.4%) received CPR from a relative, 468 (10.5%) from a work colleague or friend and 1611 (36.1%) from a stranger. Layperson's provided CPR in 3703 (83.0%) OHCA and medically trained professionals in 761 (17.0%). After adjustment for arrest characteristics, there was no difference in survival to hospital discharge between related versus unrelated CPR (adjusted odds ratio [AOR] 0.92, 95% confidence interval [CI]: 0.68-1.23, p = 0.555). However, bystander CPR by a medically trained provider rather than a layperson, was associated with an increase in the odds of survival by 47% (AOR 1.47, 95% CI: 1.09-2.00, p = 0.012) in the overall population and 73% (AOR 1.73, 95% CI: 1.21-2.49; p = 0.003) in patients with an initial shockable arrest. Adjusting for public access defibrillation significantly attenuated the effect of medically trained bystander CPR in initial shockable arrests (AOR 1.42, 95% CI: 0.97-2.07; p = 0.073).

CONCLUSION

This study supports ongoing efforts to crowdsource a larger number of first responders with medical training to OHCA patients to assist with the provision of CPR and early defibrillation.