Telecommunicator Cardiopulmonary Resuscitation: A Policy Statement From the American Heart Association

How stepwise interventions in pre-hospital emergency care enhance out-of-hospital cardiac arrest management in a Megacity in China

OBJECTIVE

A series of improvements have been formulated and implemented to prompt the inadequate pre-hospital care capacity for out-of-hospital cardiac arrest (OHCA) management in China. The aim of this study is to investigate the combined association of those stepwise interventions with OHCA management in Shenzhen, as a representative city in China.

METHODS

This registry-based retrospective study included emergency medical services (EMS)-treated adult OHCA patients with presumed cardiac etiology in Shenzhen, China, covering the period from January 1, 2011 to December 31, 2022. During this period, three key interventions were implemented sequentially: a public access defibrillation (PAD) program on October 1, 2017, a civilian cardiopulmonary resuscitation (CPR) training program on July 1, 2020, and telecommunicator cardiopulmonary resuscitation (T-CPR) on November 23, 2021. The outcomes of bystander CPR and return of spontaneous circulation (ROSC) were compared with pre-intervention controls.

RESULTS

A total of 6,571 EMS-treated presumed cardiac etiology adult OHCA patients were included, among which were 623 cases with bystander-witnessed OHCA and a shockable rhythm. Across four periods, the rates of both bystander CPR (8.55 vs. 12.60 vs. 18.31 vs. 23.10%) and ROSC (6.01 vs. 5.29 vs. 9.59 vs. 8.33%) showed an increasing trend. For the rate of bystander CPR, the likelihood was significantly increased after implementation of the PAD program (OR 1.64 [95% CI 1.21-2.23]) and civilian CPR training program (OR 2.12 [95% CI: 1.52-2.95]), and after the addition of the T-CPR application (OR 3.06 [95% CI: 2.14-4.39]), compared with the pre-period. Similarly, cumulative interventions were associated with a higher ROSC (OR 0.84 [95% CI: 0.62-1.14], OR 1.52 [95% CI: 1.07-1.89], OR 1.42 [95% CI: 1.07-1.89]) when compared with the pre-period. In subgroup analysis, cumulative interventions significantly improved the rate of bystander CPR in cases where OHCA occurred in public locations, and ROSC in cases where the time from symptom onset to calling 120 was within 10 min.

CONCLUSION

Stepwise interventions in pre-hospital emergency care increased likelihood of bystander CPR and ROSC following pre-hospital resuscitation significantly. This improvement is attributed to the coordination and cumulative effect of multiple positive interventions for OHCA management.

The impact of dispatcher-assisted CPR and prior bystander CPR training on neurologic outcomes in out-of-hospital cardiac arrest: a multicenter study

BACKGROUND

The objective of this study was to evaluate the effectiveness of dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) among laypersons, focusing on its impact on those with and without prior CPR training in out-of-hospital cardiac arrest (OHCA) cases.

METHODS

This prospective multicenter observational study included 42 emergency hospitals participating in the SOS-KANTO 2017 study (September 2019-March 2021). Patients with non-traumatic OHCA witnessed by laypersons were categorized into five groups: no bystander CPR, bystander non-DA-CPR without CPR training, bystander non-DA-CPR with CPR training, bystander DA-CPR without CPR training, and bystander DA-CPR with CPR training. The primary outcome was favorable neurological outcomes at one month.

RESULTS

Among 2,772 patients analyzed, the proportions of favorable neurological outcomes were 3.0%, 7.4%, 7.4%, 15.7%, and 25.6% in the respective groups. In multivariable analyses, the highest odds of favorable neurological outcomes were observed in the non-DA-CPR with CPR training group (OR 9.0, 95% CI 2.8-29.6), followed by the DA-CPR with CPR training group (OR 3.1, 95% CI 1.1-8.5), DA-CPR without CPR training group (OR 2.5, 95% CI 1.3-4.9), and bystander non-DA-CPR without CPR training group (OR 1.6, 95% CI 0.8-3.2), with no bystander CPR as the reference.

CONCLUSION

DA-CPR and prior CPR training play crucial roles in improving favorable neurological outcomes in bystander-witnessed OHCA cases. Additionally, DA-CPR may be particularly effective for untrained bystanders. These findings highlight the importance of integrating widespread CPR training programs and robust DA-CPR protocols into community-based emergency response systems.

Dispatcher-Assisted CPR in Italy: A Nationwide Survey of Current Practices and Future Challenges in Emergency Medical Communication Centers

Background/Objectives: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) is widely recognized as a critical intervention that significantly reduces no-flow time, improving survival rates in out-of-hospital cardiac arrests (OHCAs). This study evaluates current practices and the organization of DA-CPR in Italian emergency medical communication centers (EMCCs) and identifies areas for improvement. Methods: A cross-sectional survey was conducted between April and May 2024 among all Italian EMCCs, achieving a 92.6% response rate (62 out of 67) and covering 95.5% of the population. Data were collected on the availability of DA-CPR, additional medical instructions provided, standardized protocols, integration into dispatch software, availability of video call systems, and follow-up programs. Results: All responding EMCCs provide DA-CPR, with 79.1% (n = 49) initiating these protocols more than five years ago. In adult cardiac arrest, 74.2% (n = 46) provide instructions for chest compressions only. Standardized protocols are used in 69.4% (n = 43) of EMCCs, and 53.2% (n = 33) have these protocols integrated into their dispatch software. Additionally, 93.5% (n = 58) provide dispatcher-assisted instructions for other medical conditions, including pediatric CPR (90.3%, n = 56), neonatal CPR (90.3%, n = 56), foreign body airway obstruction (85.5%, n = 53), labor (56.5%, n = 35), and massive bleeding (41.9%, n = 26). A training path for DA-CPR is available in 48 EMCCs (77.4%), and in most cases, it is included in the basic dispatcher course (56.5%, n = 36), with 50% conducting periodic retraining. Moreover, 33.9% (n = 21) utilize video call systems to support dispatcher-assisted instructions. Data on DA-CPR are collected by 46.8% of EMCCs (n = 29), primarily on relevant cases, but only 25.8% (n = 16) have a follow-up path for patients. Conclusions: This study highlights a widespread implementation of DA-CPR across Italian EMCCs. However, regional disparities, mainly in protocols and technological support, indicate areas requiring urgent attention. Enhancing training programs and standardizing protocols could improve DA-CPR effectiveness and patient outcomes, thus guaranteeing equitable care nationwide. Future initiatives should focus on integrating support tools like video calls, expanding retraining programs, and establishing follow-up and debriefing paths.

Barriers for Responding to Pediatric Out-of-Hospital Cardiac Arrest During Emergency Medical Calls: A Qualitative Study

BACKGROUND

Rapid recognition of pediatric out-of-hospital cardiac arrest (POHCA) is a critical component to prompt initiation of bystander interventions. We aimed to investigate barriers for responding to POHCA during emergency medical calls.

METHODS AND RESULTS

We included all POHCA calls (aged 0-18 years) from the emergency dispatch center in the Capital Region of Denmark between 2018 and 2021 and excluded POHCAs with no resuscitation order, found dead, where trained health professionals were on site, or where there was no possibility for initiation of cardiopulmonary resuscitation. A qualitative analysis was undertaken. POHCA calls were divided according to the speed of telecommunicator-recognition into 3 groups: POHCA recognition within 90 seconds (group 1), POHCAs recognition >90 seconds (group 2), and POHCAs recognized by the emergency medical services at ambulance arrival (group 3). A total of 20 calls were included. We identified 3 major barriers to telecommunicator recognition of POHCA. First, prolonged conversations between callers and telecommunicators focusing on the cause of the child's condition rather than adherence to the assessment of consciousness and breathing. Second, challenges in assessing breathing such as cases where the child had agonal or unregular breathing or gasping breaths. Finally, callers who were unable to communicate or follow instructions from the telecommunicator.

CONCLUSIONS

Telecommunicator recognition of POHCA is challenged by factors such as prolonged conversations focusing on causes rather than initiating bystander interventions, barriers in assessing breathing, as well as callers' abilities to partake in communication with telecommunicators. Efforts to address these barriers in current dispatch protocols may improve recognition of POHCA.

Breaking down barriers: Call-taker strategies to address caller perception of inappropriateness of cardiopulmonary resuscitation during the emergency ambulance call

BACKGROUND

Ambulance call-takers perform the critical role of prompting callers to initiate and continue cardiopulmonary resuscitation (CPR) for patients with suspected out-of-hospital cardiac arrest (OHCA). This study aimed to identify call-taker strategies to address callers' perceptions of CPR 'inappropriateness' (perceiving the patient as dead and beyond help, or as showing signs of life).

METHODS

Using a linguistic approach, we analysed 31 calls previously identified as having an inappropriateness barrier to CPR initiation or continuation. In Phase 1, we listened to call recordings and studied call transcripts to identify the strategies and linguistic features used by call-takers. Phase 2 was a discourse analysis of transcript extracts to describe how certain strategies, identified in Phase 1, were used in the caller-call-taker interactions.

RESULTS

Call-takers used various strategies when responding to callers who considered CPR inappropriate. Call-takers rarely used a single strategy or linguistic feature in isolation, tending to use combinations of minimal tokens of alignment (e.g. caller name or encouragements statements), with deontics (including directives/commands and statements of obligation e.g. "do this for me") and provision of either context (e.g. "the ambulance is on its way") or a rationale ("he's not breathing effectively so we need to perform CPR to help him"). Most call-taker attempts were successful, with callers overcoming 71% of initiation barriers and 88% of continuation barriers.

CONCLUSIONS

Call-takers used a combination of linguistic features (minimal/symbolic tokens, deontics) and strategies (providing unscripted statements about the context or a rationale for CPR) to overcome barriers of perceived inappropriateness to CPR.

Advancements in Public First Responder Programs for Out-of-Hospital Cardiac Arrest: An Updated Literature Review

Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide, with a low survival rate of around 7% globally. Key factors for improving survival include witnessed arrest, bystander cardiopulmonary resuscitation (CPR), and early defibrillation. Despite guidelines advocating for the "chain of survival", bystander CPR and defibrillation rates remain suboptimal. Innovative approaches, such as dispatcher-assisted CPR (DA-CPR) and smartphone-based alerts, have emerged to address these challenges. DA-CPR effectively transforms emergency callers into lay rescuers, and smartphone apps are increasingly being used to alert volunteer first responders to OHCA incidents, enhancing response times and increasing survival rates. Smartphone-based systems offer advantages over traditional text messaging by providing real-time guidance and automated external defibrillator (AED) locations. Studies show improved outcomes with app-based alerts, including higher rates of early CPR, increased survival rates and improved neurological outcomes. Additionally, the potential of unmanned aerial vehicles (drones) to deliver AEDs rapidly to OHCA sites has been demonstrated, particularly in rural areas with extended emergency medical services response times. Despite technological advancements, challenges such as ensuring responder training, effective dispatching, and maintaining responder well-being, particularly during the coronavirus disease 19 (COVID-19) pandemic, remain. During the pandemic, some community first responder programs were suspended or modified due to shortages of personal protective equipment (PPE) and increased risks of infection. However, systems that adapted by using PPE and revising protocols generally maintained responder participation and effectiveness. Moving forward, integrating new technology within robust responder systems and support mechanisms will be essential to improving OHCA outcomes and sustaining effective response networks.

Language barriers in emergency ambulance calls for cardiac arrest: Cases of missing vital information

In medical emergencies, phoning the ambulance service constitutes a high-stakes interaction. Call-takers rely on callers to provide information about the patient so they can promptly recognise the medical problem and take swift action to remedy it. When a language barrier exists between the call-taker and caller, this can add a further challenge, given that third-party interpreters are rarely engaged, especially for time-critical conditions such as cardiac arrest. Research in cardiac arrest calls has found that language barrier calls experience longer delays to critical points such as recognition of cardiac arrest and commencement of resuscitation. This study aimed to understand, in the absence of interpreters, the interactional challenges that emerged in language barrier emergency calls, as parties worked to communicate the nature of the medical problem. Based on a critical conversation analysis approach, we conducted fine-grained analysis of interactions in audio recordings and transcripts of 33 language barrier calls from an Australian ambulance service in 2019. We found that call takers regularly failed to recognise that the patient had a cardiac arrest. Non-fluent-English callers often provided vital information about the patient, which could have led to cardiac arrest recognition by the call-taker, however such information was missed if it was delivered in an unsolicited or atypical way. Opportunities to recognise cardiac arrest were also missed when call-takers did not probe further after such information was provided or did not provide enough interactional space for callers to complete their turns. We found that the main reason for delays in recognising cardiac arrest was a lack of mutual understanding, which most of the time seemed to remain unbeknownst to participants. The study makes recommendations for emergency medical dispatch centres to cater for language barrier calls, with the goal of fostering a more inclusive prehospital care system and addressing health disparities for non-fluent-English speakers.

Navigating cardiac arrest together: A survivor and family-led co-design study of family needs and care touchpoints

Introduction

This study aimed to i) identify the care needs of families experiencing cardiac arrest; and ii) co-identify strategies for meeting the identified care needs. Cardiac arrest survivors and family members (of survivors and non-survivors) were engaged as "experience experts," collaborators and co-researchers in this study.

Methods

A qualitative study using semi-structured interviews of cardiac arrest survivors and family members was conducted. Participants were recruited from the membership of the Family Centred Cardiac Arrest Care Project. Interviews were recorded, transcribed, and analysed using Framework analysis.

Results

Twenty-eight participants described 22 unique cardiac arrest events. We identified five primary care need themes: 1) "Help us help our loved one"; 2) "Work with us as a cohesive team"; 3) "See us: treat us with humanity and dignity"; 4) "Address our family's ongoing emergency"; and 5) "Help us to heal after the cardiac arrest" as well as 29 subordinate care need themes. We performed touchpoint mapping to identify key moments of interaction between patients and families, and the health system to highlight potential areas for improvement, as well as strategies for meeting family care needs.

Conclusion

Our participants identified varied family care needs during and long after cardiac arrest. Fortunately, many proposed strategies are inexpensive and have low barriers to adoption. However, some unmet care needs identified suggest larger systemic issues such as service gaps that leave families feeling abandoned and isolated. Overall, our findings suggest that care during and after cardiac arrest are critical components of a comprehensive cardiac arrest care system.

RAndomized Cluster Evaluation of Cardiac ARrest Systems (RACE-CARS) trial: Study rationale and design

Out-of-hospital cardiac arrest (OHCA) occurs in nearly 350,000 people each year in the United States (US). Despite advances in pre and in-hospital care, OHCA survival remains low and is highly variable across systems and regions. The critical barrier to improving cardiac arrest outcomes is not a lack of knowledge about effective interventions, but rather the widespread lack of systems of care to deliver interventions known to be successful. The RAndomized Cluster Evaluation of Cardiac ARrest Systems (RACE-CARS) trial is a 7-year pragmatic, cluster-randomized trial of 62 counties (57 clusters) in North Carolina using an established registry and is testing whether implementation of a customized set of strategically targeted community-based interventions improves survival to hospital discharge with good neurologic function in OHCA relative to control/standard care. The multifaceted intervention comprises rapid cardiac arrest recognition and systematic bystander CPR instructions by 9-1-1 telecommunicators, comprehensive community CPR training and enhanced early automated external defibrillator (AED) use prior to emergency medical systems (EMS) arrival. Approximately 20,000 patients are expected to be enrolled in the RACE CARS Trial over 4 years of the assessment period. The primary endpoint is survival to hospital discharge with good neurologic outcome defined as a cerebral performance category (CPC) of 1 or 2. Secondary outcomes include the rate of bystander CPR, defibrillation prior to arrival of EMS, and quality of life. We aim to identify successful community- and systems-based strategies to improve outcomes of OHCA using a cluster randomized-controlled trial design that aims to provide a high level of evidence for future application.

The association of out-of-hospital cardiac arrest barriers to cardiopulmonary resuscitation initiation and continuation during the emergency call: A retrospective cohort study

Background

In a previous study, we identified eight types of potential barriers to bystander cardiopulmonary resuscitation (CPR) initiation and continuation until the arrival of emergency medical services (EMS) on scene, in the context of emergency calls for out-of-hospital cardiac arrest (OHCA). Many cases had multiple barriers. In this study, we aimed to estimate the independent effects of these barriers after adjusting for case characteristics.

Methods

We used data for the 295 non-trauma OHCAs from the St John Western Australian (SJ-WA) OHCA Database. Excluded cases were: EMS-witnessed OHCA, callers not with/close to the patient, OHCA not recognised during the emergency call, bystander CPR in progress prior to the call and calls coded as obvious death by SJ-WA. We conducted two multivariable logistic regression models including the eight barriers (callers: 1) perceived inappropriateness of CPR, 2) emotional distress, 3) reluctance to perform CPR, 4) physical limitations, 5) access to the patient, 6) leaving the scene, 7) communication failure, and 8) on-scene distractions) and case characteristics.

Results

The callers perceiving CPR as inappropriate (adjusted odds ratio [AOR] = 0.20, 0.11-0.37) and witnessed arrest (AOR = 2.88, 95% CI 1.48-5.60) were independently associated with CPR initiation. Caller distractions such as performing other tasks or relaying information to other bystanders were negatively significantly associated with callers continuing CPR to EMS arrival (AOR = 0.27, 0.10-0.73).

Conclusions

Perceptions of inappropriateness and caller distractions were independent risk factors for the delivery of bystander CPR. Further research around how call-takers navigate these barriers and encourage callers should be performed.

Barriers to successful dispatcher-assisted cardiopulmonary resuscitation in out-of-hospital cardiac arrest in Korea

Introduction

Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) improves bystander CPR rates and survival outcomes. This study aimed to identify barriers to successful DA-CPR in patients with out-of-hospital cardiac arrest (OHCA).

Methods

This retrospective observational study used data from a nationwide OHCA database from 2017 to 2021. Adult emergency medical services (EMS)-treated patients with OHCA with a presumed cardiac etiology were enrolled. The main exposure variable was compliance with DA-CPR. The primary outcome was good neurological recovery at hospital discharge. Multivariable logistic regression analysis was conducted to identify the major factors associated with unsuccessful DA-CPR with and without multiple imputations. Causal mediation analysis was conducted using witnessed status as a mediator.

Results

In the final analysis, 49,165 patients with OHCA were included. A total of 36,865 (75.0%) patients successfully underwent DA-CPR. A higher proportion of good neurological recovery was observed in the successful DA-CPR group than in the non-successful DA-CPR group (P < 0.001). The following factors were identified as risk factors for unsuccessful DA-CPR: age > 65 years, male sex, OHCA occurring in a non-metropolitan area or private place, unwitnessed status, whether the bystander was a non-family member or non-cohabitant, female sex or had not received CPR training, and primary call dispatchers not receiving any first-aid training. Additional analyses after multiple imputations showed similar results. Mediation effect was significant for most risk factors for unsuccessful DA-CPR.

Conclusions

Bystander characteristics (non-family member or non-cohabitant, female, and uneducated status for CPR) and primary call dispatchers not receiving first-aid training were identified as risk factors for unsuccessful DA-CPR.

Cardiac Arrest and Cardiopulmonary Resuscitation Outcome Reports: 2024 Update of the Utstein Out-of-Hospital Cardiac Arrest Registry Template

The Utstein Out-of-Hospital Cardiac Arrest Resuscitation Registry Template, introduced in 1991 and updated in 2004 and 2015, standardizes data collection to enable research, evaluation, and comparisons of systems of care. The impetus for the current update stemmed from significant advances in the field and insights from registry development and regional comparisons. This 2024 update involved representatives of the International Liaison Committee on Resuscitation and used a modified Delphi process. Every 2015 Utstein data element was reviewed for relevance, priority (core or supplemental), and improvement. New variables were proposed and refined. All changes were voted on for inclusion. The 2015 domains-system, dispatch, patient, process, and outcomes-were retained. Further clarity is provided for the definitions of out-of-hospital cardiac arrest attended resuscitation and attempted resuscitation. Changes reflect advancements in dispatch, early response systems, and resuscitation care, as well as the importance of prehospital outcomes. Time intervals such as emergency medical service response time now emphasize precise reporting of the times used. New flowcharts aid the reporting of system effectiveness for patients with an attempted resuscitation and system efficacy for the Utstein comparator group. Recognizing the varying capacities of emergency systems globally, the writing group provided a minimal dataset for settings with developing emergency medical systems. Supplementary variables are considered useful for research purposes. These revisions aim to elevate data collection and reporting transparency by registries and researchers and to advance international comparisons and collaborations. The overarching objective remains the improvement of outcomes for patients with out-of-hospital cardiac arrest.

Cardiac arrest and cardiopulmonary resuscitation outcome reports: 2024 update of the Utstein Out-of-Hospital Cardiac Arrest Registry template

The Utstein Out-of-Hospital Cardiac Arrest Resuscitation Registry Template, introduced in 1991 and updated in 2004 and 2015, standardizes data collection to enable research, evaluation, and comparisons of systems of care. The impetus for the current update stemmed from significant advances in the field and insights from registry development and regional comparisons. This 2024 update involved representatives of the International Liaison Committee on Resuscitation and used a modified Delphi process. Every 2015 Utstein data element was reviewed for relevance, priority (core or supplemental), and improvement. New variables were proposed and refined. All changes were voted on for inclusion. The 2015 domains-system, dispatch, patient, process, and outcomes-were retained. Further clarity is provided for the definitions of out-of-hospital cardiac arrest attended resuscitation and attempted resuscitation. Changes reflect advancements in dispatch, early response systems, and resuscitation care, as well as the importance of prehospital outcomes. Time intervals such as emergency medical service response time now emphasize precise reporting of the times used. New flowcharts aid the reporting of system effectiveness for patients with an attempted resuscitation and system efficacy for the Utstein comparator group. Recognizing the varying capacities of emergency systems globally, the writing group provided a minimal dataset for settings with developing emergency medical systems. Supplementary variables are considered useful for research purposes. These revisions aim to elevate data collection and reporting transparency by registries and researchers and to advance international comparisons and collaborations. The overarching objective remains the improvement of outcomes for patients with out-of-hospital cardiac arrest.

Combinations of First Responder and Drone Delivery to Achieve 5-Minute AED Deployment in OHCA

Background

Defibrillation in the critical first minutes of out-of-hospital cardiac arrest (OHCA) can significantly improve survival. However, timely access to automated external defibrillators (AEDs) remains a barrier.

Objectives

The authors estimated the impact of a statewide program for drone-delivered AEDs in North Carolina integrated into emergency medical service and first responder (FR) response for OHCA.

Methods

Using Cardiac Arrest Registry to Enhance Survival registry data, we included 28,292 OHCA patients ≥18 years of age between 1 January 2013 and 31 December 2019 in 48 North Carolina counties. We estimated the improvement in response times (time from 9-1-1 call to AED arrival) achieved by 2 sequential interventions: 1) AEDs for all FRs; and 2) optimized placement of drones to maximize 5-minute AED arrival within each county. Interventions were evaluated with logistic regression models to estimate changes in initial shockable rhythm and survival.

Results

Historical county-level median response times were 8.0 minutes (IQR: 7.0-9.0 minutes) with 16.5% of OHCAs having AED arrival times of <5 minutes (IQR: 11.2%-24.3%). Providing all FRs with AEDs improved median response to 7.0 minutes (IQR: 6.2-7.8 minutes) and increased OHCAs with <5-minute AED arrival to 22.3% (IQR: 16.4%-30.9%). Further incorporating optimized drone networks (326 drones across all 48 counties) improved median response to 4.8 minutes (IQR: 4.3-5.2 minutes) and OHCAs with <5-minute AED arrival to 56.3% (IQR: 46.9%-64.2%). Survival rates were estimated to increase by 34% for witnessed OHCAs with estimated drone arrival <5 minutes and ahead of FR and emergency medical service.

Conclusions

Deployment of AEDs by FRs and optimized drone delivery can improve AED arrival times which may lead to improved clinical outcomes. Implementation studies are needed.

Current trends in the management of out of hospital cardiac arrest (OHCA)

Sudden cardiac arrest remains a relevant problem with a significant number of deaths worldwide. Although survival rates have more than tripled over the last 20 years (4% in 2001 vs. 14% in 2020), survival rates with good neurological outcomes remain persistently low, representing a major socioeconomic problem. Every minute of delay from patient collapse to start cardiopulmonary resuscitation (CPR) and early defibrillation reduces the chance of survival by approximately 10-12%. Therefore, the time to treatment is a crucial factor in the prognosis of patients with out-of-hospital cardiac arrest (OHCA). Research teams working in the pre-hospital setting are therefore looking for ways to improve the transmission of information from the site of an emergency event and to make it easier for emergency medical dispatch centres (EMDC) to recognise life-threatening conditions with minimal deviation. For emergency unit procedures already at the scene of the event, methods are being sought to efficiently and temporarily replace a non-functioning cardiopulmonary system. In the case of traumatic cardiac arrest (TCA), the focus is mainly on effective affecting non-compressible haemorrhage.

Bystander cardiopulmonary resuscitation differences by sex - The role of arrest recognition

PURPOSE

To assess whether bystander cardiopulmonary resuscitation (CPR) differed by patient sex among bystander-witnessed out-of-hospital cardiac arrests (OHCA).

METHODS

This study is a retrospective analysis of paramedic-attended OHCA in New South Wales (NSW) between January 2017 to December 2019 (restricted to bystander-witnessed cases). Exclusions included OHCA in aged care, medical facilities, with advance care directives, from non-medical causes. Multivariate logistic regression examined the association of patient sex with bystander CPR. Secondary outcomes were OHCA recognition, bystander AED application, initial shockable rhythm, and survival outcomes.

RESULTS

Of 4,491cases, females were less likely to receive bystander CPR in private residential (Adjusted Odds ratio [AOR]: 0.82, 95%CI: 0.70-0.95) and public locations (AOR: 0.58, 95%CI:0.39-0.88). OHCA recognition during the emergency call was lower for females arresting in public locations (84.6% vs 91.6%, p = 0.002) and this partially explained the association of sex with bystander CPR (∼44%). This difference in recognition was not observed in private residential locations (p = 0.2). Bystander AED use was lower for females (4.8% vs 9.6%, p < 0.001); however, after adjustment for location and other covariates, this relationship was no longer significant (AOR: 0.83, 95%CI: 0.60-1.12). Females were less likely to be in an initial shockable rhythm (AOR: 0.52, 95%CI: 0.44-0.61), but more likely to survive the event (AOR: 1.34, 95%CI: 1.15-1.56). There was no sex difference in survival to hospital discharge (AOR: 0.96, 95%CI: 0.77-1.19).

CONCLUSION

OHCA recognition and bystander CPR differ by patient sex in NSW. Research is needed to understand why this difference occurs and to raise public awareness of this issue.

Challenges and best practices of dispatcher-assisted cardiopulmonary resuscitation: A scoping review protocol

Introduction

Improved survival from out-of-hospital cardiac arrest with good neurological outcome was observed in association with dispatcher-assisted cardiopulmonary resuscitation, increasing the number of bystander-initiated resuscitations and minimizing the no-flow time in the first minutes of cardiac arrest.

Objective

The objective of this scoping review is to map and summarise the existing literature on dispatcher-assisted cardiopulmonary resuscitation, focusing on reported experiences, challenges, and best practices, highlighting strategies that could improve the provision of cardiopulmonary resuscitation instructions to bystanders during out-of-hospital cardiac arrest.

Inclusion criteria

Studies related to dispatcher-assisted cardiopulmonary resuscitation, involving human subjects, with an English abstract. The concept of interest is focused on the methods of provision of dispatcher-assisted cardiopulmonary resuscitation analysing specific experiences of implementation, challenges, and best practices, and can be generalized to any country; cultural factors, geographic features, and specific racial or gender-based differences will be analysed and discussed.

Methods

Four databases (PubMed, Embase, Cumulative Index to Nursing & Allied Health Literature, and the Cochrane Library) will be searched for studies published from 2018 to 2023. All study designs, including experimental and observational studies, will be assessed for inclusion. Titles and abstracts of identified citations will be screened for inclusion; subsequently, full texts of potentially relevant sources will be assessed for inclusion by two reviewers. Any disagreements between the reviewers will be resolved through discussion. Relevant grey literature (conference proceedings, government documents, and theses) will be analysed and included. Data will be extracted in a standardized form, following Joanna Briggs Institute recommendations. Results will be synthesized and reported using a narrative approach, categorising findings into themes related to the effectiveness of dispatcher-assisted cardiopulmonary resuscitation, challenges, and best practices.

Pakistan's Emergency Medical Services (EMS) system & out-of-hospital-cardiac-arrest (OHCA): A narrative review of an EMS system of a low middle income country in context of OHCA

Pakistan's Emergency Medical Services (EMS) are a critical component of its healthcare system, providing pre-hospital emergency care across a nation with over 220 million people. This article explores the evolutionary journey of Pakistan's EMS, highlighting both the challenges it faces and the strides it has made, with a specific emphasis on patients experiencing out-of-hospital cardiac arrest (OHCA). To extract relevant information, we searched MEDLINE & Embase data bases using MeSH terms "Emergency Medical Services" OR "EMS" AND "Out-of-Hospital-Cardiac-Arrest" OR "OHCA" AND "Pakistan". In addition, we also retrieved information from the EMS leadership in Pakistan through e-mails. We delve into the significance of key performance indicators for OHCA, advocate for the establishment of OHCA registries to improve patient outcomes, address regional disparities in pre-hospital care, and acknowledge the gradual progress of the EMS system.

The barriers and facilitators to initiation of telephone-assisted bystander cardiopulmonary resuscitation for patients experiencing out-of-hospital cardiac arrest in a private emergency dispatch centre in South Africa

Background

The incidence of cardiovascular diseases, and with it out-of-hospital cardiac arrest (OHCA), is on the increase in low- to middle-income countries (LMICs), like South Africa. Interventions such as mass public cardiopulmonary resuscitation (CPR) training campaigns and public access defibrillators are expensive and out of reach for many LMICs. Telephone-assisted CPR (tCPR) is a cost-effective, scalable alternative. This study explored the barriers and facilitators to tCPR uptake in OHCA in a private South African emergency dispatch centre.

Methods

This qualitative study applied inductive dominant content analysis to emergency call recordings of OHCA cases into a private emergency dispatch centre. Calls were analysed to the latent level to identify barriers and facilitators. Cases were sampled randomly, until data saturation.

Results

Saturation occurred after the analysis of 25 recordings. A further three recordings were analysed to confirm saturation of the facilitators; yielding a final sample size of 28 calls. Overall, t-CPR was offered in 23 (82.1%) cases, but only initiated in 8 (34.8%) of these calls. Five barriers ("Poor Communication"; "Lack of Support"; "Caller Hesitance or Uncertainty;" "Emotionality"; and "Practical Barriers") and three facilitators ("Caller Willingness"; "Support" and "CPR in Progress") were extracted.

Conclusion

Numerous barriers limit the initiation of tCPR in the South African private sector EMS. It is crucial to address these barriers and leverage the facilitators in order to improve tCPR uptake. This study highlights the importance of using specific language techniques and developing tailored tCPR algorithms to overcome these barriers, which is underpinned by standardised training of call-takers.

Outline and validation of a new dispatcher-assisted cardiopulmonary resuscitation educational bundle using the Delphi method

Aim

Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) is time-dependent. To date, evidence-based training programmes for dispatchers are lacking. This study aimed to reach expert consensus on an educational bundle content for dispatchers to provide DA-CPR using the Delphi method.

Method

An educational bundle was created by the Swedish Resuscitation Council consisting of three parts: e-learning on DA-CPR, basic life support training and audit of emergency out-of-hospital cardiac arrest calls. Thereafter, a two-round modified Delphi study was conducted between November 2022 and March 2023; 37 experts with broad clinical and/or scientific knowledge of DA-CPR were invited. In the first round, the experts participated in the e-learning module and answered a questionnaire with 13 closed and open questions, whereafter the e-learning part of the bundle was revised. In the second round, the revised e-learning part was evaluated using Likert scores (20 items). The predefined consensus level was set at 80%.

Results

Delphi rounds one and two were assessed by 20 and 18 of the invited experts, respectively. In round one, 18 experts (18 of 20, 90%) stated that they did not miss any content in the programme. In round two, the scale-level content validity index based on the average method (S-CVI/AVE, 0.99) and scale-level content validity index based on universal agreement (S-CVI/UA, 0.85) exceeded the threshold level of 80%.

Conclusion

Expert consensus on the educational bundle content was reached using the Delphi method. Further work is required to evaluate its effect in real-world out-of-hospital cardiac arrest calls.

Compression-Only or Standard Cardiopulmonary Resuscitation for Trained Laypersons in Out-of-Hospital Cardiac Arrest: A Nationwide Randomized Trial in Sweden

BACKGROUND

The ongoing TANGO2 (Telephone Assisted CPR. AN evaluation of efficacy amonGst cOmpression only and standard CPR) trial is designed to evaluate whether compression-only cardiopulmonary resuscitation (CPR) by trained laypersons is noninferior to standard CPR in adult out-of-hospital cardiac arrest. This pilot study assesses feasibility, safety, and intermediate clinical outcomes as part of the larger TANGO2 survival trial.

METHODS

Emergency medical dispatch calls of suspected out-of-hospital cardiac arrest were screened for inclusion at 18 dispatch centers in Sweden between January 1, 2017, and March 12, 2020. Inclusion criteria were witnessed event, bystander on the scene with previous CPR training, age above 18 years of age, and no signs of trauma, pregnancy, or intoxication. Cases were randomized 1:1 at the dispatch center to either instructions to perform compression-only CPR (intervention) or instructions to perform standard CPR (control). Feasibility included evaluation of inclusion, randomization, and adherence to protocol. Safety measures were time to emergency medical service dispatch CPR instructions, and to start of CPR, intermediate clinical outcome was defined as 1-day survival.

RESULTS

Of 11 838 calls of suspected out-of-hospital cardiac arrest screened for inclusion, 2168 were randomized and 1250 (57.7%) were out-of-hospital cardiac arrests treated by the emergency medical service. Of these, 640 were assigned to intervention and 610 to control. Crossover from intervention to control occurred in 16.3% and from control to intervention in 18.5%. The median time from emergency call to ambulance dispatch was 1 minute and 36 s (interquartile range, 1.1-2.2) in the intervention group and 1 minute and 30 s (interquartile range, 1.1-2.2) in the control group. Survival to 1 day was 28.6% versus 28.4% (P=0.984) for intervention and control, respectively.

CONCLUSIONS

In this national randomized pilot trial, compression-only CPR versus standard CPR by trained laypersons was feasible. No differences in safety measures or short-term survival were found between the 2 strategies. Efforts to reduce crossover are important and may strengthen the ongoing main trial that will assess differences in long-term survival.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02401633.

Factors influencing support for the implementation of community-based out-of-hospital cardiac arrest interventions in high- and low-performing counties

Aim of the study

Survival to hospital discharge from out-of-hospital cardiac arrest (OHCA) after receiving treatment from emergency medical services (EMS) is less than 10% in the United States. Community-focused interventions improve survival rates, but there is limited information on how to gain support for new interventions or program activities within these populations. Using data from the RAndomized Cluster Evaluation of Cardiac ARrest Systems (RACE-CARS) trial, we aimed to identify the factors influencing emergency response agencies' support in implementing an OHCA intervention.

Methods

North Carolina counties were stratified into high-performing or low-performing counties based on the county's cardiac arrest volume, percent of bystander-cardiopulmonary resuscitation (CPR) performed, patient survival to hospital discharge, cerebral performance in patients after cardiac arrest, and perceived engagement in the RACE-CARS project. We randomly selected 4 high-performing and 3 low-performing counties and conducted semi-structured qualitative interviews with emergency response stakeholders in each county.

Results

From 10/2021 to 02/2022, we completed 29 interviews across the 7 counties (EMS (n = 9), telecommunications (n = 7), fire/first responders (n = 7), and hospital representatives (n = 6)). We identified three themes salient to community support for OHCA intervention: (1) initiating support at emergency response agencies; (2) obtaining support from emergency response agency staff (senior leadership and emergency response teams); and (3) and maintaining support. For each theme, we described similarities and differences by high- and low-performing county.

Conclusions

We identified techniques for supporting effective engagement of emergency response agencies in community-based interventions for OHCA improving survival rates. This work may inform future programs and initiatives around implementation of community-based interventions for OHCA.

Barriers to CPR initiation and continuation during the emergency call relating to out-of-hospital cardiac arrest: A descriptive cohort study

AIM

To describe the barriers to cardiopulmonary resuscitation (CPR) initiation and continuation in emergency calls for out-of-hospital cardiac arrest (OHCA).

METHODS

We analysed 295 consecutive emergency calls relating to OHCA over a four-month period (1 January - 30 April 2021). Calls included were paramedic-confirmed, non-traumatic, non-EMS-witnessed OHCA, where the caller was with the patient. Calls were listened to in full and coded in terms of barriers to CPR initiation and continuation, and patient and caller characteristics.

RESULTS

Overall, CPR was performed in 69% of calls and, in 85% of these, callers continued performing CPR until EMS arrival. Nearly all callers (99%) experienced barriers to CPR initiation and/or continuation during the call. The barriers identified were classified into eight categories: reluctance, appropriateness, emotion, bystander physical ability, patient access, leaving the scene, communication failure, caller actions and call-taker instructions. Of these, bystander physical ability was the most prevalent barrier to both CPR initiation and continuation, occurring in 191 (65%) calls, followed by communication failure which occurred in 160 (54%) calls. Callers stopping or interrupting CPR performance due to being fatigued was lower than expected (n = 54, 26% of callers who performed CPR). Barriers to CPR initiation that related to bystander physical ability, caller actions, communication failure, emotion, leaving the scene, patient access, procedural barriers, and reluctance were mostly overcome by the caller (i.e., CPR was performed).

CONCLUSION

Barriers to CPR initiation and continuation were commonly experienced by callers, however they were frequently overcome. Future research should investigate the strategies that were successful.

Pediatric Out-of-Hospital Cardiac Arrest: The Role of the Telecommunicator in Recognition of Cardiac Arrest and Delivery of Bystander Cardiopulmonary Resuscitation

BACKGROUND

Telecommunicator CPR (T-CPR), whereby emergency dispatch facilitates cardiac arrest recognition and coaches CPR over the telephone, is an important strategy to increase early recognition and bystander CPR in adult out-of-hospital cardiac arrest (OHCA). Little is known about this treatment strategy in the pediatric population. We investigated the role of T-CPR and related performance among pediatric OHCA.

METHODS AND RESULTS

This study was a retrospective cohort investigation of OHCA among individuals <18 years in King County, Washington, from April 1, 2013, to December 31, 2019. We reviewed the 911 audio recordings to determine if and how bystander CPR was delivered (unassisted or T-CPR), key time intervals in recognition of arrest, and key components of T-CPR delivery. Of the 185 eligible pediatric OHCAs, 23% (n=43) had bystander CPR initiated unassisted, 59% (n=109) required T-CPR, and 18% (n=33) did not receive CPR before emergency medical services arrival. Among all cases, cardiac arrest was recognized by the telecommunicator in 89% (n=165). Among those receiving T-CPR, the median (interquartile range) interval from start of call to OHCA recognition was 59 seconds (38-87) and first CPR intervention was 115 seconds (94-162). When stratified by age (≤8 versus >8), the older age group was less likely to receive CPR before emergency medical services arrival (88% versus 69%, P=0.002). For those receiving T-CPR, bystanders spent a median of 207 seconds (133-270) performing CPR. The median compression rate was 93 per minute (82-107) among those receiving T-CPR.

CONCLUSIONS

T-CPR is an important strategy to increase early recognition and early CPR among pediatric OHCA.

Incidence, process of care, and outcomes of out-of-hospital cardiac arrest in China: a prospective study of the BASIC-OHCA registry

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is an important global public health issue, but its epidemiology and outcomes in low-income and middle-income countries remain largely unknown. We aim to comprehensively describe the incidence, process of care, and outcomes of OHCA in China.

METHODS

In the prospective, multicentre, population-based Baseline Investigation of Out-of-hospital Cardiac Arrest (BASIC-OHCA) registry study, participating sites were selected from both urban and rural areas in all seven geographical regions across China. All patients with OHCA assessed by emergency medical service (EMS) staff were consecutively enrolled from Aug 1, 2019, to Dec 31, 2020. Patients with suspected cardiac arrest assessed by bystanders whose return of spontaneous circulation was achieved without the need for defibrillation or EMS personnel cardiopulmonary resuscitation were excluded. Patients with all key variables missing were excluded, including resuscitation attempt, age, sex, witnessed status, cause, all process of care indicators, and all outcome measures. In this analysis, we included data for EMS agencies serving 25 monitoring sites (20 urban and five rural) that included the entire serving population, data for the whole of 2020, and at least 50 OHCA patients in 2020. Data were collected and reported using the Utstein template. We calculated the crude incidence of EMS-assessed OHCA in 2020. We also report data on baseline characteristics (including sex, cause, location of OHCA, and presence of shockable rhythm), process of care (including EMS response time, cardiopulmonary resuscitation, defibrillation, and advanced life support), and outcomes of non-traumatic OHCA between Aug 1, 2019, and Dec 31, 2020, including survival and survival with favourable neurological outcomes at discharge or 30 days, and at 6 and 12 months.

FINDINGS

Of 115·1 million people served by the 25 participating sites, 132 262 EMS-assessed patients with OHCA were enrolled, and resuscitation was attempted for 42 054 (31·8%) patients between Aug 1, 2019, and Dec 31, 2020. The crude incidence of EMS-assessed OHCA was 95·7 per 100 000 population (95% CI 95·6-95·8) in 2020. Among 38 227 individuals with non-traumatic OHCA, 25 958 (67·9%) were male, 30 282 (79·2%) had a cardiac arrest at home, 32 523 (85·1%) had a presumed cardiac cause, and 2297 (6·0%) presented with an initial shockable rhythm. 4049 (11·5%) of 35 090 patients with an unwitnessed or bystander-witnessed OHCA received dispatcher-assisted cardiopulmonary resuscitation and 7121 (20·3%) received bystander cardiopulmonary resuscitation; only 14 (<0·1%) patients were assessed by bystanders with an automated external defibrillator. The median EMS response time was 12 min (IQR 9-16). At hospital discharge or 30 days, 441 (1·2%) of 38 227 survived, 304 (0·8%) survived up to 6 months, and 269 (0·7%) up to 12 months. At hospital discharge or 30 days, 309 (0·8%) survived with favourable neurological outcomes, 257 (0·7%) had favourable neurological outcomes at 6 months, and 236 (0·6%) at 12 months.

INTERPRETATION

Our findings revealed a high burden of EMS-assessed OHCA with a low proportion of resuscitation attempts. The suboptimal implementation of chain of survival and unsatisfactory prognosis call for national efforts to improve the care and outcomes of patients with OHCA in China.

FUNDING

The National Science & Technology Fundamental Resources Investigation Program of China, the State Key Program of the National Natural Science Foundation of China, Taishan Pandeng Scholar Program of Shandong Province, the Key Research & Development Program of Shandong Province, the Interdisciplinary Young Researcher Groups Program of Shandong University, the Clinical Research Center of Shandong University, the ECCM Program of Clinical Research Center of Shandong University, and the Natural Science Foundation of Shandong Province.

The understandability and quality of telephone-guided bystander cardiopulmonary resuscitation in the Western Cape province of South Africa: A manikin-based study

Background

The incidence of cardiovascular disease is on the increase in Africa and with it, an increase in the incidence of out-of-hospital cardiac arrest (OHCA). OHCA carries a high mortality, especially in low-resource settings. Interventions to treat OHCA, such as mass cardiopulmonary resuscitation (CPR) training campaigns are costly. One cost-effective and scalable intervention is telephone-guided bystander CPR (tCPR). Little data exists regarding the quality of tCPR. This study aimed to determine quality of tCPR in untrained members of the public. Participants were also asked to provide their views on the understandability of the tCPR instructions.

Methods

This study followed a prospective, simulation-based observational study design. Adult laypeople who have not had previous CPR training were recruited at public CPR training events and asked to perform CPR on a manikin. Quality was assessed in terms of hand placement, compression rate, compression depth, chest recoil, and chest exposure. tCPR instructions were provided by a trained medical provider, via loudspeaker. Participants were also asked to complete a short questionnaire afterwards, detailing the understandability of the tCPR instructions. Data were analysed descriptively and compared to recommended quality guidance.

Results

Fifty participants were enrolled. Hand placement was accurate in 74 % (n = 37) of participants, while compression depth and chest recoil only had compliance in 20 % (n = 10) and 24 % (n = 12) of participants, respectively. The mean compression rate was within guidelines in just under half (48 %, n = 24) of all participants. Only 20 (40 %) participants exposed the manikin's chest. Only 46 % (n = 23) of participants felt that the overall descriptions offered during the tCPR guidance were understandable, while 80 % (n = 40) and 36 % (n = 18) felt that the instructions on hand placement and compression rate were understandable, respectively. Lastly, 94 % (n = 47) of participants agreed that they would be more likely to perform bystander CPR if they were provided with tCPR.

Conclusion

The quality of CPR performed by laypersons is generally suboptimal and this may affect patient outcomes. There is an urgent need to develop more understandable tCPR algorithms that may encourage bystanders to start CPR and optimise its quality.

Presentation and Outcomes of Adults With Overdose-Related Out-of-Hospital Cardiac Arrest

Importance

Drug overdose (OD) is a public health challenge and an important cause of out-of-hospital cardiac arrest (OHCA). Existing studies evaluating OD-related OHCA (OD-OHCA) either aggregate all drugs or focus on opioids. The epidemiology, presentation, and outcomes of drug-specific OHCA are largely unknown.

Objective

To evaluate the temporal pattern, clinical presentation, care, and outcomes of adult patients with OHCA overall and according to the drug-specific profile.

Design, Setting, and Participants

This cohort study of adults with OHCA in King County Washington was conducted between January 1, 2015, and December 31, 2021. Etiology of OHCA was determined using emergency medical service, hospital, and medical examiner records. Etiology was classified as non-OD OHCA or OD-OHCA, with drug-specific profiles categorized as (1) opioid without stimulant, (2) stimulant without opioid, (3) opioid and stimulant, or (4) all other nonstimulant, nonopioid drugs. Statistical analysis was performed on July 1, 2023.

Exposure

Out-of-hospital cardiac arrest.

Main Outcomes and Measures

The primary outcome was survival to hospital discharge. The secondary outcome was survival with favorable functional status defined by Cerebral Performance Category 1 or 2 based on review of the hospital record.

Results

In this cohort study, there were 6790 adult patients with emergency medical services-treated OHCA from a US metropolitan system. During the 7-year study period, there were 702 patients with OD-OHCA (median age, 41 years [IQR, 29-53 years]; 64% male [n = 450] and 36% female [n = 252]) and 6088 patients with non-OD OHCA (median age, 66 years [IQR, 56-77 years]; 65% male [n = 3944] and 35% female [n = 2144]). The incidence of OD-OHCA increased from 5.2 (95% CI, 3.8-6.6) per 100 000 person-years in 2015 to 13.0 (95% CI, 10.9-15.1) per 100 000 person-years in 2021 (P < .001 for trend), whereas there was no significant temporal change in the incidence of non-OD OHCA (P = .30). OD-OHCA were more likely to be unwitnessed (66% [460 of 702] vs 41% [2515 of 6088]) and less likely to be shockable (8% [56 of 702] vs 25% [1529 of 6088]) compared with non-OD OHCA. Unadjusted survival was not different (20% [138 of 702] for OD vs 18% [1095 of 6088] for non-OD). When stratified by drug profile, combined opioid-stimulant OHCA demonstrated the greatest relative increase in incidence. Presentation and outcomes differed by drug profile. Patients with stimulant-only OHCA were more likely to have a shockable rhythm (24% [31 of 129]) compared with patients with opioid-only OHCA (4% [11 of 295]) or patients with combined stimulant-opioid OHCA 5% [10 of 205]), and they were more likely to have a witnessed arrest (50% [64 of 129]) compared with patients with OHCA due to other drugs (19% [14 of 73]) or patients with combined stimulant-opioid OHCA (23% [48 of 205]). Patients with a combined opioid-stimulant OHCA had the lowest survival to hospital discharge (10% [21 of 205]) compared with patients with stimulant-only OHCA (22% [29 of 129]) or patients with OHCA due to other drugs (26% [19 of 73]), a difference that persisted after multivariable adjustment.

Conclusions and Relevance

In a population-based cohort study, the incidence of OD-OHCA increased significantly from 2015 to 2021, with the greatest increase observed among patients with a combined stimulant-opioid OHCA. Presentation and outcome differed according to the drug-specific profile. The combination of increasing incidence and lower survival among among patients with a opioid-stimulant OHCA supports prevention and treatment initiatives that consider the drug-specific profile.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

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

OBJECTIVE

There are over 300,000 out-of-hospital cardiac arrests (OHCA) annually in the United States (US) and despite many scientific advances in the field, the survival rate remains low. We seek to determine if return of spontaneous circulation (ROSC) is higher when use of emergency medical dispatch (EMD) protocols is documented for OHCA calls compared to when no EMD protocol use is documented. We also seek identify care-related processes that differ in calls that use EMD protocols.

METHODS

This is a retrospective cohort study of U.S. adults with OHCA prior to emergency medical services (EMS) arrival using 2019 National EMS Information System data. The primary exposure was EMD usage during EMS call. The primary outcome was prehospital ROSC, and secondary outcomes included automated external defibrillator (AED) use before EMS arrival, bystander CPR, and end-of-event EMS survival (survival to the end of the EMS care at transport destination). Multivariable logistic regression adjusted for age, sex, race/ethnicity, primary insurance, rurality, initial rhythm, arrest etiology, and witnessed arrest.

RESULTS

Of the 96,269 OHCA cases included, EMD use was documented in 73%. Overall, 26% of subjects achieved ROSC in EMS care. EMD subjects were more likely to achieve ROSC (27.2% vs. 23.5%, uOR 1.22, 95%CI 1.18 - 1.26) even after adjusting for subject and arrest characteristics (aOR 1.13, 95%CI 1.08 - 1.17). EMD subjects also had higher end-of-event survival (19.1% vs. 16.4%, aOR 1.20, 95%CI 1.15 - 1.25). AED use before EMS arrival was more common in the EMD group (28.3% vs. 26.3% %diff 2.0, 95%CI 1.4 to 2.6), as was CPR before EMS arrival (63.8% vs. 55.1%, difference 8.6%, 95%CI 7.9 to 9.3%).

CONCLUSIONS

In this retrospective analysis, the rate of ROSC was higher in adult OHCA patients when EMD protocol use was reported compared to when it was not reported. The group with documented EMD use also experienced higher rates of bystander AED use, bystander CPR, and end-of-event survival.

Swedish emergency medical dispatch centres' ability to answer emergency medical calls and dispatch an ambulance in response to out-of-hospital cardiac arrest calls in accordance with the American Heart Association performance goals: An observational study

AIM

To investigate the ability of Swedish Emergency Medical Dispatch Centres (EMDCs) to answer medical emergency calls and dispatch an ambulance for out-of-hospital cardiac arrest (OHCA) in accordance with the American Heart Association (AHA) performance goals in a 1-step (call connected directly to the EMDC) and a 2-step (call transferred to regional EMDC) procedure over 10 years, and to assess whether delays may be associated with 30-day survival.

METHOD

Observational data from the Swedish Registry for Cardiopulmonary Resuscitation and EMDC.

RESULTS

A total of 9,174,940 medical calls were answered (1-step). The median answer delay was 7.3 s (interquartile range [IQR], 3.6-14.5 s). Furthermore, 594,008 calls (6.1%) were transferred in a 2-step procedure, with a median answer delay of 39 s (IQR, 30-53 s). A total of 45,367 cases (0.5%, 1-step) were registered as OHCA, with a median answer delay of 7.2 s (IQR, 3.6-14.1 s) (AHA high-performance goal, 10 s). For 1-step procedure, no difference in 30-day survival was found regarding answer delay. For OHCA (1-step), an ambulance was dispatched after a median of 111.9 s (IQR, 81.7-159.9 s). Thirty-day survival was 10.8% (n = 664) when an ambulance was dispatched within 70 s (AHA high-performance) versus 9.3% (n = 2174) > 100 s (AHA acceptable) (p = 0.0013). Outcome data in the 2-step procedure was unobtainable.

CONCLUSION

The majority of calls were answered within the AHA performance goals. When an ambulance was dispatched within the AHA high-performance standard in response to OHCA calls, survival was higher compared with calls when dispatch was delayed.

Characterization of non-cardiac arrest PulsePoint activations in public and private settings

BACKGROUND

Geospatial smartphone application alert systems are used in some communities to crowdsource community response for out-of-hospital cardiac arrest (OHCA). Although the clinical focus of this strategy is OHCA, dispatch identification of OHCA is imperfect so that activation may occur for the non-arrest patient. The frequency and clinical profile of such non-arrest patients has not been well-investigated.

METHODS

We undertook a prospective 3-year cohort investigation of patients for whom a smartphone geospatial application was activated for suspected OHCA in four United States communities (total population ~1 million). The current investigation evaluates those patients with an activation for suspected OHCA who did not experience cardiac arrest. The volunteer response cohort included off-duty, volunteer public safety personnel (verified responders) notified regardless of location (public or private) and laypersons notified to public locations. The study linked the smartphone application information with the EMS records to report the frequency, condition type, and EMS treatment for these non-arrest patients.

RESULTS

Of 1779 calls where volunteers were activated, 756 had suffered OHCA, resulting in 1023 non-arrest patients for study evaluation. The most common EMS assessments were syncope (15.9%, n=163), altered mental status (15.5%, n=159), seizure (14.3%, n=146), overdose (13.0%, n=133), and choking (10.5%, n=107). The assessment distribution was similar for private and public locations. Overall, the most common EMS interventions included placement of an intravenous line (43.1%, n=441), 12-Lead ECG(27.9%, n=285), naloxone treatment (9.8%, n=100), airway or ventilation assistance (8.7%, n=89), and oxygen administration (6.6%, n=68).

CONCLUSIONS

More than half of patients activated for suspected OHCA had conditions other than cardiac arrest. A subset of these conditions may benefit from earlier care that could be provided by both layperson and public safety volunteers if they were appropriately trained and equipped.

Association between bystander physical limitations, delays in chest compression during telecommunicator-assisted cardiopulmonary resuscitation, and outcome after out-of-hospital cardiac arrest

BACKGROUND

Promptly initiated bystander cardiopulmonary resuscitation (CPR) improves survival from out-of-hospital cardiac arrest (OHCA). Many OHCA patients require repositioning to a firm surface. We examined the association between repositioning, chest compression (CC) delay, and patient outcomes.

METHODS

We used a quality improvement registry from review of 9-1-1 dispatch audio recordings of OHCA among adults eligible for telecommunicator-assisted CPR (T-CPR) between 2013 and 2021. OHCA was categorized into 3 groups: CC not delayed, CC delayed due to bystander physical limitations to reposition the patient, or CC delayed for other (non-physical) reasons. The primary outcome was the repositioning interval, defined as the interval between the start of positioning instructions and CC onset. We used logistic regression to assess the odds ratio of survival according to CPR group, adjusting for potential confounders.

RESULTS

Of the 3,482 OHCA patients eligible for T-CPR, CPR was not delayed in 1,223 (35%), delayed due to repositioning in 1,413 (41%), and delayed for other reasons in 846 (24%). The repositioning interval was longest for the physical limitation delay group (137 secs, IQR-148) compared to the other delay group (81 secs, IQR-70) and the no delay group (51 secs, IQR-32) (p < 0.001). Unadjusted survival was lowest in the physical limitation delay group (11%) versus the no delay (17%) and other delay (19%) groups and persisted after adjustment (p = 0.009).

CONCLUSION

Bystander physical limitations are a common barrier to repositioning patients to begin CPR and are associated with lower likelihood of receiving CPR, longer times to begin CC, and lower survival.

Effectiveness of Lay Bystander Hands-Only Cardiopulmonary Resuscitation on a Mattress versus the Floor: A Randomized Cross-Over Trial

STUDY OBJECTIVE

Bystander cardiopulmonary resuscitation increases the likelihood of out-of-hospital cardiac arrest survival by more than two-fold. A common barrier to the prompt initiation of compressions is moving victims to the floor, but compression quality on a "floor" versus a "mattress" has not been tested among lay bystanders.

METHODS

We conducted a prospective, randomized, cross-over trial comparing lay bystander compression quality using a manikin on a bed versus the floor. Participants included adults without professional health care training. We randomized participants to the order of manikin placement, either on a mattress or on the floor. For both, participants were instructed to perform 2 minutes of chest compressions on a cardiopulmonary resuscitation Simon manikin Gaumard (Gaumard Scientific, Miami, FL). The primary outcome was mean compression depth (cm) over 2 minutes. We fit a linear regression model adjusted for scenario order, age, sex, and body mass index with robust standard errors to account for repeated measures and reported mean differences with 95% confidence intervals (CIs).

RESULTS

Our sample of 80 adults was 66% female with a mean age of 50.5 years (SD 18.2). The mean compression depth on the mattress was 2.9 cm (SD 2.3) and 3.5 cm (SD 2.2) on the floor, a mean difference of 0.58 cm (95% CI 0.18, 0.98). Compression depth fell below the 5 to 6 cm depth recommended by the American Heart Association on both surfaces. In the adjusted model, the mean depth was greater when the manikin was on the floor than the mattress (adjusted mean difference 0.62 cm; 95% CI 0.23 to 1.01), and mean depth was less for females than males (adjusted mean difference -1.42 cm, 95% CI -2.59, -0.25). In addition, the difference in compression depth was larger for female participants (mean difference 0.94 cm; 95% CI 0.54, 1.34) than for male participants (mean difference -0.01 cm; 95% CI -0.80, 0.78), and the interaction was statistically significant (P = .04).

CONCLUSION

The mean compression depth was significantly smaller on the mattress and with female bystanders. Further research is needed to understand the benefit of moving out-of-hospital cardiac arrest victims to the floor relative to the detrimental effect of delaying chest compressions.

Secondary Public Safety Answering Points Delay the Response to out of Hospital Cardiac Arrest

Background: National guidelines recommend that high-performing systems process 9-1-1 calls within 60 s and deliver the first telecommunicator cardiopulmonary resuscitation compression within 90 s. The inability of systems employing secondary public safety answering points (PSAPs) to capture the call arrival timestamp at the primary PSAP is a challenge in out-of-hospital cardiac arrest response time research.Objective: We sought to measure the interval from call receipt at primary PSAPs to call answer at secondary PSAPs in metropolitan areas.Methods: This was a retrospective observational study evaluating 9-1-1 call transfers between PSAPs serving large urban populations. Call transfer records were extracted from the 9-1-1 telephony systems at the primary and secondary PSAPs covering seven metropolitan EMS systems. For each transferred call, we obtained the call arrival timestamp at both the primary and secondary PSAPs. The primary outcome was the interval between these two times. Results were compared to a national standard of 90% of calls forwarded within 30 s of receipt.Results: Data collected at seven metropolitan EMS agencies from January 1, 2021, through June 30, 2021, yielded 299,679 records for evaluation. The median interval required to transfer a 9-1-1 caller from primary to secondary PSAPs was 41 s (IQR 31, 59), and 86 s at the 90th percentile. The 90th percentile performance level at individual agencies ranged from 63 s to 117 s.Conclusions: The primary to secondary PSAP transfer interval lengths observed in this study preclude these EMS agencies from meeting out-of-hospital cardiac arrest performance recommendations at the 90% percentile performance level.

Factors Impacting Treatment of Out-of-Hospital Cardiac Arrest: A Qualitative Study of Emergency Responders

Background Of the more than 250 000 emergency medical services-treated out-of-hospital cardiac arrests that occur each year in the United States, only about 8% survive to hospital discharge with good neurologic function. Treatment for out-of-hospital cardiac arrest involves a system of care that includes complex interactions among multiple stakeholders. Understanding the factors inhibiting optimal care is fundamental to improving outcomes. Methods and Results We conducted group interviews with emergency responders including 911 telecommunicators, law enforcement officers, firefighters, and transporting emergency medical services personnel (ie, emergency medical technicians and paramedics) who responded to the same out-of-hospital cardiac arrest incident. We used the American Heart Association System of Care as the framework for our analysis to identify themes and their contributory factors from these interviews. We identified 5 themes under the structure domain, which included workload, equipment, prehospital communication structure, education and competency, and patient attitudes. In the process domain, 5 themes were identified focusing on preparedness, field response and access to patient, on-scene logistics, background information acquisition, and clinical interventions. We identified 3 system themes including emergency responder culture; community support, education, and engagement; and stakeholder relationships. Three continuous quality improvement themes were identified, which included feedback provision, change management, and documentation. Conclusions We identified structure, process, system, and continuous quality improvement themes that may be leveraged to improve outcomes for out-of-hospital cardiac arrest. Interventions or programs amenable to rapid implementation include improving prearrival communication between agencies, appointing patient care and logistical leadership on-scene, interstakeholder team training, and providing more standardized feedback to all responder groups.

Potential to enhance telephone cardiopulmonary resuscitation with improved instructions - findings from a simulation-based manikin study with lay rescuers

BACKGROUND

Telephone-Cardiopulmonary Resuscitation (T-CPR) significantly increases rate of bystander resuscitation and improves patient outcomes after out-of-hospital cardiac arrest (OHCA). Nevertheless, securing correct execution of instructions remains a difficulty. ERC Guidelines 2021 recommend standardised instructions with continuous evaluation. Yet, there are no explicit recommendations on a standardised wording of T-CPR in the German language. We investigated, whether a modified wording regarding check for breathing in a German T-CPR protocol improved performance of T-CPR.

METHODS

A simulation study with 48 OHCA scenarios was conducted. In a non-randomised trial study lay rescuers were instructed using the real-life-CPR protocol of the regional dispatch centre and as the intervention a modified T-CPR protocol, including specific check for breathing (head tilt-chin lift instructions). Resuscitation parameters were assessed with a manikin and video recordings.

RESULTS

Check for breathing was performed by 64.3% (n = 14) of the lay rescuers with original wording and by 92.6% (n = 27) in the group with modified wording (p = 0.035). In the original wording group the head tilt-chin manoeuvre was executed by 0.0% of the lay rescuers compared to 70.3% in the group with modified wording (p < 0.001). The average duration of check for breathing was 1 ± 1 s in the original wording group and 4 ± 2 s in the group with modified wording (p < 0.001). Other instructions (e.g. check for consciousness and removal of clothing) were well performed and did not differ significantly between groups. Quality of chest compression did not differ significantly between groups, with the exception of mean chest compression depth, which was slightly deeper in the modified wording group.

CONCLUSION

Correct check for breathing seems to be a problem for lay rescuers, which can be decreased by describing the assessment in more detail. Hence, T-CPR protocols should provide standardised explicit instructions on how to perform airway assessment. Each protocol should be evaluated for practicability.

Barriers to the Initiation of Telecommunicator-CPR during 9-1-1 Out-of-Hospital Cardiac Arrest Calls: A Qualitative Study

INTRODUCTION

Fewer than 10% of individuals who suffer out-of-hospital cardiac arrest (OHCA) survive with good neurologic function. Bystander CPR more than doubles the chance of survival, and telecommunicator-CPR (T-CPR) during a 9-1-1 call substantially improves the frequency of bystander CPR.

OBJECTIVE

We examined the barriers to initiation of T-CPR.

METHODS

We analyzed the 9-1-1 call audio from 65 EMS-treated OHCAs from a single US 9-1-1 dispatch center. We initially conducted a thematic analysis aimed at identifying barriers to the initiation of T-CPR. We then conducted a conversation analysis that examined the interactions between telecommunicators and bystanders during the recognition phase (i.e., consciousness and normal breathing).

RESULTS

We identified six process themes related to barriers, including incomplete or delayed recognition assessment, delayed repositioning, communication gaps, caller emotional distress, nonessential questions and assessments, and caller refusal, hesitation, or inability to act. We identified three suboptimal outcomes related to arrest recognition and delivery of chest compressions, which are missed OHCA identification, delayed OHCA identification and treatment, and compression instructions not provided following OHCA identification. A primary theme observed during missed OHCA calls was incomplete or delayed recognition assessment and included failure to recognize descriptors indicative of agonal breathing (e.g., "snoring", "slow") or to confirm that breathing was effective in an unconscious victim.

CONCLUSIONS

We observed that modifiable barriers identified during 9-1-1 calls where OHCA was missed, or treatment was delayed, were often related to incomplete or delayed recognition assessment. Repositioning delays were a common barrier to the initiation of chest compressions.

Prone Dispatch-Directed CPR in Out-of-Hospital Cardiac Arrest: Two Successful Cases

Historically, dispatch-directed cardiopulmonary resuscitation (CPR) protocols only allow chest compression instructions to be delivered for patients able to be placed in the traditional supine position. For patients who are unable to be positioned supine, the telecommunicator and caller have no option except to continue attempts to position supine, which may result in delayed or no chest compressions being delivered prior to emergency medical services arrival. Any delay or lack of bystander chest compressions may result in worsening clinical outcomes of out-of-hospital cardiac arrest (OHCA) victims. We present the first two cases, to the best of our knowledge, of successfully delivered, bystander-administered, prone CPR instructions by a trained telecommunicator for two OHCA victims unable to be positioned supine.

The impact of COVID-19 pandemic on out-of-hospital cardiac arrest system-of-care: Which survival chain factor contributed the most?

OBJECTIVES

In many communities, out-of-hospital cardiac arrest (OHCA) survival outcomes decreased after the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to identify and compare the impacts of each survival chain factor on the change of survival outcomes after COVID-19.

METHODS

Using a Korean out-of-hospital cardiac arrest registry, we analyzed OHCA patients whose arrest was not witnessed by emergency medical service (EMS) providers between 2017 and 2021. Because lack of hospital and survival information in 2021, the 2021 data were used only to identify the expected trend. We developed a prediction model for survival to discharge using patients from 2017 to 2019 (Pre-COVID-19 set) and validated it using patients from 2020 (post-COVID-19 set). Using Utstein elements, a stepwise logistic regression model was constructed, and discrimination and calibration were evaluated by c-statistics and scaled Brier score. Using the distribution change of predictors from one year before the pandemic (2019) to post-COVDI-19, we calculated the magnitude of survival difference according to each predictor's distribution change using the marginal standardization method.

RESULTS

Among 83,273 patients (mean age 67.2 years and 64.3% males), 61,180 and 22,092 patients belonged to pre-COVOD-19 and post-COVID-19 sets. Survival to discharge was 5019 (8.2%) in pre-COVID-19 set and 1457 (6.6%) in post-COVID-19 set. The proportion of bystander cardiopulmonary resuscitation was 59.0% in the pre-COVID-19 set and 61.0% in the post-COVID-19 set. The median (interquartile range) response time was 7 (5-9) minutes in the pre-COVID-19 set and 8 (6-10) minutes in the post-COVID-19 set. The area under the receiver operating characteristic (AUROC) curve (95% confidence interval) was 0.907 (0.902-0.912) in the pre-COVID-19 set, and 0.924 (0.916-0.931) in the post-COVID-19 set, and scaled Brier score were 0.39 in pre-COVID-19 sets, and 0.40 in the post-COVID-19 set. Among various predictors, EMS factors showed the highest impact. Response time and on-scene management of EMS showed the highest impact on decreased survival. A similar trend was also expected in the 2021.

CONCLUSION

The effort to create a rapid response system for OHCA patients could have priority for the recovery of survival outcomes in OHCA patients in the post-COVID-19 period. Further studies to recover survival outcomes of OHCA are warranted.

Performance of the medical priority dispatch system in correctly classifying out-of-hospital cardiac arrests as appropriate for resuscitation

BACKGROUND

Emergency dispatch centres receive emergency calls and assign resources. Out-of-hospital cardiac arrests (OHCA) can be classified as appropriate (requiring emergent response) or inappropriate (requiring non-emergent response) for resuscitation. We sought to determine system accuracy in emergency medical services (EMS) OHCA response allocation.

METHODS

We analyzed EMS-assessed non-traumatic OHCA records from the British Columbia (BC) Cardiac Arrest registry (January 1, 2019-June 1, 2021), excluding EMS-witnessed cases. In BC the "Medical Priority Dispatch System" is used. We classified EMS dispatch as "emergent" or "non-emergent" and compared to the gold standard of whether EMS personnel decided treatment was appropriate upon scene arrival. We calculated sensitivity, specificity, and positive and negative predictive values (PPV, NPV), with 95% CI's.

RESULTS

Of 15,371 non-traumatic OHCAs, the median age was 65 (inter quartile range 51-78), and 4834 (31%) were women; 7152 (47%) were EMS-treated, of whom 651 (9.1%) survived). Among EMS-treated cases 6923/7152 had an emergent response (sensitivity = 97%, 95% CI 96-97) and among EMS-untreated cases 3951/8219 had a non-emergent response (specificity = 48%, 95% CI, 47 to 49). Among cases with emergent dispatch, 6923/11191 were EMS-treated (PPV = 62%, 95% CI 61-62), and among those with non-emergent dispatch, 3951/4180 were EMS-untreated (NPV = 95%, 95% CI 94-95); 229/4180 (5.5%) with a non-emergent dispatch were treated by EMS.

CONCLUSION

The dispatch system in BC has a high sensitivity and moderate specificity in sending the appropriate responses for OHCAs deemed appropriate for treatment by paramedics. Future research may address strategies to increase system specificity, and decrease the incidence of non-emergent dispatch to EMS-treated cases.

A scoping review to determine the barriers and facilitators to initiation and performance of bystander cardiopulmonary resuscitation during emergency calls

Background

To maximise out-of-hospital cardiac arrest (OHCA) patients' survival, bystanders should perform continuous, good quality cardiopulmonary resuscitation (CPR) until ambulance arrival.

Objectives

To identify published literature describing barriers and facilitators between callers and call-takers, which affect initiation and performance (continuation and quality) of bystander CPR (B-CPR) throughout the OHCA emergency call.

Eligibility criteria

Studies were included if they reported on the population (emergency callers and call-takers), concept (psychological, physical and communication barriers and facilitators impacting the initiation and performance of B-CPR) and context (studies that analysed OHCA emergency calls).

Sources of evidence

Medline, CINAHL, Cochrane CENTRAL, Embase, Scopus and ProQuest were searched from inception to 9 March 2022.

Charting methods

Study characteristics were extracted and presented in a narrative format accompanied by summary tables.

Results

Thirty studies identified factors that impacted B-CPR initiation or performance during the emergency call. Twenty-eight studies described barriers to the provision of CPR instructions and CPR initiation, with prominent themes being caller reluctance (psychological), physical ability (physical), and callers hanging up the phone prior to CPR instructions (communication). There was little evidence examining barriers and facilitators to ongoing CPR performance (2 studies) or CPR quality (2 studies).

Conclusions

This scoping review using emergency calls as the source, described barriers to the provision of B-CPR instructions and B-CPR initiation. Further research is needed to explore facilitators and barriers to B-CPR continuation and quality throughout the emergency call, and to examine the effectiveness of call-taker strategies to motivate callers to perform B-CPR.

Early recognition of a caller's emotion in out-of-hospital cardiac arrest dispatching: An artificial intelligence approach

AIM

This study aimed to develop an AI model for detecting a caller's emotional state during out-of-hospital cardiac arrest calls by processing audio recordings of dispatch communications.

METHODS

Audio recordings of 337 out-of-hospital cardiac arrest calls from March-April 2011 were retrieved. The callers' emotional state was classified based on the emotional content and cooperative scores. Mel-frequency cepstral coefficients extracted essential information from the voice signals. A support vector machine was utilised for the automatic judgement, and repeated random sub-sampling cross validation (RRS-CV) was applied to evaluate robustness. The results from the artificial intelligence classifier were compared with the consensus of expert reviewers.

RESULTS

The audio recordings were classified into five emotional content and cooperative score levels. The proposed model had an average positive predictive value of 72.97%, a negative predictive value of 93.47%, sensitivity of 38.76%, and specificity of 98.29%. If only the first 10 seconds of the recordings were considered, it had an average positive predictive value of 84.62%, a negative predictive value of 93.57%, sensitivity of 52.38%, and specificity of 98.64%. The artificial intelligence model's performance maintained preferable results for emotionally stable cases.

CONCLUSION

Artificial intelligence models can possibly facilitate the judgement of callers' emotional states during dispatch conversations. This model has the potential to be utilised in practice, by pre-screening emotionally stable callers, thus allowing dispatchers to focus on cases that are judged to be emotionally unstable. Further research and validation are required to improve the model's performance and make it suitable for the general population.

Out-of-hospital cardiac arrests in the city of Cape Town, South Africa: a retrospective, descriptive analysis of prehospital patient records

OBJECTIVES

While prospective epidemiological data for out-of-hospital cardiac arrest (OHCA) exists in many high-income settings, there is a dearth of such data for the African continent. The aim of this study was to describe OHCA in the Cape Town metropole, South Africa.

DESIGN

Observational study with a retrospective descriptive design.

SETTING

Cape Town metropole, Western Cape province, South Africa.

PARTICIPANTS

All patients with OHCA for the period 1 January 2018-31 December 2018 were extracted from public and private emergency medical services (EMS) and described.

OUTCOME MEASURES

Description of patients with OHCA in terms of demographics, treatment and short-term outcome.

RESULTS

A total of 929 patients with OHCA received an EMS response in the Cape Town metropole, corresponding to an annual prevalence of 23.2 per 100 000 persons. Most patients were adult (n=885; 96.5%) and male (n=526; 56.6%) with a median (IQR) age of 63 (26) years. The majority of cardiac arrests occurred in private residences (n=740; 79.7%) and presented with asystole (n=322; 34.6%). EMS resuscitation was only attempted in 7.4% (n=69) of cases and return of spontaneous circulation (ROSC) occurred in 1.3% (n=13) of cases. Almost all patients (n=909; 97.8%) were declared dead on the scene.

CONCLUSION

To our knowledge, this was the largest study investigating OHCA ever undertaken in Africa. We found that while the incidence of OHCA in Cape Town was similar to the literature, resuscitation is attempted in very few patients and ROSC-rates are negligible. This may be as a consequence of protracted response times, poor patient prognosis or an underdeveloped and under-resourced Chain of Survival in low- to middle-income countries, like South Africa. The development of contextual guidelines given resources and disease burden is essential.

Out of hospital cardiac arrest: Past, present, and future

Advances in resuscitation following out-of-hospital cardiac arrest (OHCA) provide an opportunity to improve public health. This review reflects on past developments, present status, and future possibilities using the science-education-implementation framework of the Utstein Formula and the clinical framework of the links in the chain of survival. With the discovery of CPR and defibrillation in the mid 20th century, resuscitation developed a scientific construct for progress. Systems of emergency community response provided operational efficiency to treat OHCA. Contemporary resuscitation involves integrated interventions in the chain of survival: early recognition, early CPR, early defibrillation, expert and timely advanced life support and hospital care, and multidimensional rehabilitation. Implementation of scientific advances is especially challenging given the unexpected nature of OHCA, the need for time-sensitive interventions, and the substantial collective of stakeholders involved in the chain of survival. Systematic measurement provides the foundation to evaluate performance and guide implementation initiatives. For many systems, telecommunicator CPR and high-performance CPR by emergency professionals are accessible, near-term programs to improve OHCA outcome. Smart technologies that activate, coordinate, and/or coach community "volunteers" to accelerate early CPR and defibrillation have conceptual promise, though robust implementation has been achieved by only a handful of systems. Longer-term strategies may leverage technology to develop a high-fidelity "life-detector" or engineer and disseminate a specialized consumer defibrillator designed to bridge care until arrival of professional response.