Out-of-hospital cardiac arrest: prehospital management

Negotiating grey areas: an interview-based analysis of paramedic uncertainty and decision-making in cardiac arrest events

BACKGROUND

Paramedics are responsible for critical resuscitation decisions when attending Out of Hospital Cardiac Arrests (OHCA). Existing research indicates that a range of clinical and non-clinical factors moderate their decision-making. Within the United Kingdom (UK), there is little evidence on how and why paramedics make their decisions at actual OHCA events.

METHODS

We explored the experiences of UK paramedics using individually recalled OHCA events as catalysts for discussion. Pen portraits developed from semi-structured interviews with 31 paramedics across two UK ambulance services were thematically analysed, enabling cross-participant comparisons whilst retaining depth and context.

RESULTS

We identified four themes: uncertainties encountered in resuscitation guidelines, influences on decision-making, holistic perspectives, and indirect moderators. We found that paramedics experienced uncertainty at all stages of the resuscitation process. Uncertainties arose from indeterminate, ambiguous or complex information and were described as having both clinical and ethical dimensions. Whilst guidelines drove paramedics' decisions, non-clinical personal, practical and relational factors moderated their assessments of survivability and decision-making, with attitudes to interactions between patient age, frailty and quality of life playing a substantial role. Coping strategies such as uncertainty reduction, assumption-based reasoning and weighing pros and cons were evident from interviews.

CONCLUSIONS

The complexity of interactions between clinical and non-clinical factors points to an element of variability in paramedics' responses to uncertainty. Exploring UK paramedics' uncertainties and decision-making during specific OHCA events can help acknowledge and address uncertainties in resuscitation guidelines and paramedic training, providing paramedics with the tools to manage uncertainty in a consistent and transparent way.

Should basic life support-defibrillator training be compulsory for newly licensed Italian physicians? An observational study

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is a relevant event with a fatal outcome in most cases. Basic life support-defibrillator (BLSD) training is central to rescuing a patient in arrest and ensuring that the patient has a better chance of returning to spontaneous circulation. Despite this, BLSD training is not mandatory for newly licensed physicians. Our study aims to evaluate the preparedness of newly qualified doctors to manage an OHCA and the impact of BLSD training.

MATERIALS AND METHODS

We tested 120 newly qualified doctors, members of the 'Italian Society of Medicine and Scientific Divulgation' network, evaluating their practical and theoretical knowledge in managing an OHCA before and after a BLSD training course conducted according to the American Heart Association guidelines.

RESULTS

Fifty-nine physicians (49.2%) had an adequate background of the theoretical basis of cardiopulmonary resuscitation (CPR); 37 (30.8%) were able to perform effective CPR on a mannequin, but only 19 (15.8%) were able to perform effective CPR with adequate depth and frequency of compressions. After the BLSD training course, 111 physicians (92.5%) were able to perform effective and quality CPR on a mannequin with feedback.

CONCLUSION

In Italy, BLSD training for physicians is not mandatory, and newly licensed physicians showed good knowledge of the theoretical basis of CPR, but few of them performed compressions of adequate depth and frequency. These results should guide future educational policy decisions in Italian academies.

Refining ambulance clinical response models: The impact on ambulance response and emergency department presentations

OBJECTIVE

The ambulance service in Victoria, Australia implemented a revised clinical response model (CRM) in 2016 which was designed to increase the diversion of low-acuity Triple Zero (000) calls to secondary telephone triage and reduce emergency ambulance dispatches. The present study evaluates the influence of the revised CRM on emergency ambulance response times and ED presentations.

METHODS

A retrospective study of emergency calls for ambulance between 1 January 2015 and 31 December 2018. Ambulance data were linked with ED presentations occurring up to 48 h after contact. Interrupted time series analyses were used to evaluate the impact of the revised CRM.

RESULTS

A total of 2 365 529 calls were included. The proportion allocated a Code 1 (time-critical, lights/sirens) dispatch decreased from 56.6 to 41.0% after implementation of the revised CRM. The proportion of calls not receiving an emergency ambulance increased from 10.4 to 19.6%. Interrupted time series analyses demonstrated an improvement in Code 1 cases attended within 15 min (Key Performance Indicator). However, for patients with out-of-hospital cardiac arrest or requiring lights and sirens transport to hospital, there was no improvement in response time performance. By the end of the study period, there was also no difference in the proportion of callers presenting to ED when compared with the estimated proportion assuming the revised CRM had not been implemented.

CONCLUSION

The revised CRM was associated with improved Code 1 response time performance. However, there was no improvement in response times for high acuity patients, and no change in the proportion of callers presenting to ED.

Comparison of pre-hospital management of out-of-hospital cardiac arrest and its outcomes between the COVID-19 and pre-COVID-19 periods

Out-of-hospital cardiac arrest (OHCA) is a time-sensitive medical emergency that needs immediate interventions. COVID-19 affected the performance of the emergency medical service (EMS) system in pre-hospital care, including the management of cardiac arrest. This study aimed to identify the impact of the COVID-19 pandemic on pre-hospital management of out-of-hospital cardiac arrest and its outcome in Qom City, Iran. In this descriptive-analytical study, the data were collected from the electronic registration system of the EMS center in Qom, Iran. All OHCA patients who received resuscitation during COVID-19 and before COVID-19 were enrolled in the study. Data consisted of the characteristics of OHCA patients, EMS interventions and response times, and the outcome of OHCA. A P-value of <0.05 was deemed statistically significant. 630 OHCA patients in the COVID-19 period and 524 OHCA patients in the pre-COVID-19 period were included in the study. Endotracheal intubation and defibrillation were done more in the COVID-19 period than in the pre-COVID-19 period (50.2 % vs. 17 %, p<0.001 %, and 40.1 % vs. 22.5 %, p < 0.001, respectively). The EMS response time was longer during the COVID-19 pandemic (9.1 ± 3.9 min vs. 7.6 ± 1.4 min, p < 0.001). The rate of pre-hospital return of spontaneous circulation (ROSC) was lower in the COVID-19 period (15.6 % vs. 8.4 %, p < 0.001). According to univariate analysis, ROSC was predicted by COVID-19 (p < 0.001). However, COVID-19 was not the statistically significant independent predictor after multivariate analysis (p < 0.67). The COVID-19 pandemic period influenced OHCA and ROSC. Also, it affected pre-hospital management in the OHCA situation. The negative impact of COVID-19 on the EMS response reflected the need to know and remove barriers to managing crises such as COVID-19.

Implementation of basic life support education for the lay public in China: barriers, enablers, and possible solutions

Background

Education for the lay public in basic life support (BLS) is critical for increasing bystander cardiopulmonary resuscitation (CPR) rates and improving survival from out-of-hospital cardiac arrest (OHCA). Despite years of implementation, the BLS training rate in China has remained modest. The aim of this study was to investigate the factors influencing the implementation of BLS training programs in emergency medical service (EMS) centers in China and to identify specific barriers and enablers.

Methods

Qualitative interviews were conducted with key informants from 40 EMS centers in Chinese cities. The participants included 11 directors/deputy directors, 24 training department leaders, and 5 senior trainers. The interview guide was based on the Exploration, Preparation, Implementation, Sustainment (EPIS) framework. Thematic content analysis was used to identify themes and patterns across the interviews.

Results

We identified 16 factors influencing the implementation of BLS training programs encompassing the outer content, inner context, innovation and bridging factors. Some factors acted as either barriers or enablers at different EPIS stages. The main implementation barriers included limited external leadership, insufficient government investment, low public awareness, a shortage of trainers, an absence of incentives, an absence of authoritative courses and guidelines, a lack of qualification to issue certificates, limited academic involvement, and insufficient publicity. The main enablers were found to be supportive government leaders, strong public demand, adequate resources, program champions, available high-quality courses of high fitness within the local context, the involvement of diverse institutions, and effective publicity and promotion.

Conclusion

Our findings emphasize the diversity of stakeholders, the complexity of implementation, and the need for localization and co-construction when conducting BLS training for lay public in city EMS centers. Improvements can be made at the national level, city level, and EMS institutional level to boost priority and awareness, promote legislation and policies, raise sustainable resources, and enhance the technology of BLS courses.

Association of socioeconomic status with 30-day survival following out-of-hospital cardiac arrest in Scotland, 2011-2020

BACKGROUND AND AIMS

The aim of this study was to investigate the crude and adjusted association of socioeconomic status with 30-day survival after out-of-hospital cardiac arrest (OHCA) in Scotland and to assess whether the effect of this association differs by sex or age.

METHODS

This is a population-based, retrospective cohort study, including non-traumatic, non-Emergency Medical Services witnessed patients with OHCA where resuscitation was attempted by the Scottish Ambulance Service, between 1 April 2011 and 1 March 2020. Socioeconomic status was defined using the Scottish Index of Multiple Deprivation (SIMD). The primary outcome was 30-day survival after OHCA. Crude and adjusted associations of SIMD quintile with 30-day survival after OHCA were estimated using logistic regression. Effect modification by age and sex was assessed by stratification.

RESULTS

Crude analysis showed lower odds of 30-day survival in the most deprived quintile relative to least deprived [odds ratio (OR) 0.74, 95% confidence interval (CI) 0.63-0.88]. Adjustment for age, sex, and urban/rural residency decreased the relative odds of survival further (OR 0.56, 95% CI 0.47-0.67). The strongest association was observed in males <45 years old. Across quintiles of increasing deprivation, evidence of decreasing trends in the proportion of those presenting with shockable initial cardiac rhythm, those receiving bystander cardiopulmonary resuscitation, and 30-day survival after OHCA were found.

CONCLUSIONS

Socioeconomic status is associated with 30-day survival after OHCA in Scotland, favouring people living in the least deprived areas. This was not explained by confounding due to age, sex, or urban/rural residency. The strongest association was observed in males <45 years old.

Socioeconomic disadvantage and long-term survival duration in out-of-hospital cardiac arrest patients: A population-based cohort study

Background

Socioeconomic status (SES) is a well-established determinant of cardiovascular health. However, the relationship between SES and clinical outcomes in long-term out-of-hospital cardiac arrest (OHCA) is less well-understood. The Singapore Housing Index (SHI) is a validated building-level SES indicator. We investigated whether SES as measured by SHI is associated with long-term OHCA survival in Singapore.

Methods

We conducted an open cohort study with linked data from the Singapore Pan-Asian Resuscitation Outcomes Study (PAROS), and the Singapore Registry of Births and Deaths (SRBD) from 2010 to 2020. We fitted generalized structural equation models, calculating hazard ratios (HRs) using a Weibull model. We constructed Kaplan-Meier survival curves and calculated the predicted marginal probability for each SHI category.

Results

We included 659 cases. In both univariable and multivariable analyses, SHI did not have a significant association with survival. Indirect pathways of SHI mediated through covariates such as Emergency Medical Services (EMS) response time (HR of low-medium, high-medium and high SHI when compared to low SHI: 0.98 (0.88-1.10), 1.01 (0.93-1.11), 1.02 (0.93-1.12) respectively), and age of arrest (HR of low-medium, high-medium and high SHI when compared to low SHI: 1.02 (0.75-1.38), 1.08 (0.84-1.38), 1.18 (0.91-1.54) respectively) had no significant association with OHCA survival. There was no clear trend in the predicted marginal probability of survival among the different SHI categories.

Conclusions

We did not find a significant association between SES and OHCA survival outcomes in residential areas in Singapore. Among other reasons, this could be due to affordable healthcare across different socioeconomic classes.

Emergent Management of Hypoxic-Ischemic Brain Injury

OBJECTIVE

This article outlines interventions used to improve outcomes for patients with hypoxic-ischemic brain injury after cardiac arrest.

LATEST DEVELOPMENTS

Emergent management of patients after cardiac arrest requires prevention and treatment of primary and secondary brain injury. Primary brain injury is minimized by excellent initial resuscitative efforts. Secondary brain injury prevention requires the detection and correction of many pathophysiologic processes that may develop in the hours to days after the initial arrest. Key physiologic parameters important to secondary brain injury prevention include optimization of mean arterial pressure, cerebral perfusion, oxygenation and ventilation, intracranial pressure, temperature, and cortical hyperexcitability. This article outlines recent data regarding the treatment and prevention of secondary brain injury. Different patients likely benefit from different treatment strategies, so an individualized approach to treatment and prevention of secondary brain injury is advisable. Clinicians must use multimodal sources of data to prognosticate outcomes after cardiac arrest while recognizing that all prognostic tools have shortcomings.

ESSENTIAL POINTS

Neurologists should be involved in the postarrest care of patients with hypoxic-ischemic brain injury to improve their outcomes. Postarrest care requires nuanced and patient-centered approaches to the prevention and treatment of primary and secondary brain injury and neuroprognostication.

Mortality, morbidity & clinical outcome with different types of vasopressors in out of hospital cardiac arrest patients- a systematic review and meta-analysis

BACKGROUND & OBJECTIVE

Despite their continued use, the effectiveness and safety of vasopressors in post-cardiac arrest patients remain controversial. This study examined the efficacy of various vasopressors in cardiac arrest patients in terms of clinical, morbidity, and mortality outcomes.

METHODS

A comprehensive literature search was performed using online databases (MeSH terms: MEDLINE (Ovid), CENTRAL (Cochrane Library), Embase (Ovid), CINAHL, Scopus, and Google Scholar) from 1997 to 2023 for relevant English language studies. The primary outcomes of interest for this study included short-term survival leading to death, return of spontaneous circulation (ROSC), survival to hospital discharge, neurological outcomes, survival to hospital admission, myocardial infarction, and incidence of arrhythmias.

RESULTS

In this meta-analysis, 26 studies, including 16 RCTs and ten non-RCTs, were evaluated. The focus was on the efficacy of epinephrine, vasopressin, methylprednisolone, dopamine, and their combinations in medical emergencies. Epinephrine treatment was associated with better odds of survival to hospital discharge (OR = 1.52, 95%CI [1.20, 1.94]; p < 0.001) and achieving ROSC (OR = 3.60, 95% CI [3.45, 3.76], P < 0.00001)) over placebo but not in other outcomes of interest such as short-term survival/ death at 28-30 days, survival to hospital admission, or neurological function. In addition, our analysis indicates non-superiority of vasopressin or epinephrine vasopressin-plus-epinephrine therapy over epinephrine monotherapy except for survival to hospital admission where the combinatorial therapy was associated with better outcome (0.76, 95%CI [0.64, 0.92]; p = 0.004). Similarly, we noted the non-superiority of vasopressin-plus-methylprednisolone versus placebo. Finally, while higher odds of survival to hospital discharge (OR = 3.35, 95%CI [1.81, 6.2]; p < 0.001) and ROSC (OR = 2.87, 95%CI [1.97, 4.19]; p < 0.001) favoring placebo over VSE therapy were observed, the risk of lethal arrhythmia was not statistically significant. There was insufficient literature to assess the effects of dopamine versus other treatment modalities meta-analytically.

CONCLUSION

This meta-analysis indicated that only epinephrine yielded superior outcomes among vasopressors than placebo, albeit limited to survival to hospital discharge and ROSC. Additionally, we demonstrate the non-superiority of vasopressin over epinephrine, although vasopressin could not be compared to placebo due to the paucity of data. The addition of vasopressin to epinephrine treatment only improved survival to hospital admission.

Development of a Predictive Model for Survival Over Time in Patients With Out-of-Hospital Cardiac Arrest Using Ensemble-Based Machine Learning

As of now, a model for predicting the survival of patients with out-of-hospital cardiac arrest has not been established. This study aimed to develop a model for identifying predictors of survival over time in patients with out-of-hospital cardiac arrest during their stay in the emergency department, using ensemble-based machine learning. A total of 26 013 patients from the Korean nationwide out-of-hospital cardiac arrest registry were enrolled between January 1 and December 31, 2019. Our model, comprising 38 variables, was developed using the Survival Quilts model to improve predictive performance. We found that changes in important variables of patients with out-of-hospital cardiac arrest were observed 10 minutes after arrival at the emergency department. The important score of the predictors showed that the influence of patient age decreased, moving from the highest rank to the fifth. In contrast, the significance of reperfusion attempts increased, moving from the fourth to the highest rank. Our research suggests that the ensemble-based machine learning model, particularly the Survival Quilts, offers a promising approach for predicting survival in patients with out-of-hospital cardiac arrest. The Survival Quilts model may potentially assist emergency department staff in making informed decisions quickly, reducing preventable deaths.

Overview and future prospects of out-of-hospital cardiac arrest registries in Japan

Aim

Out-of-hospital cardiac arrest (OHCA) is a life-threatening emergency with high mortality. The "chain of survival" is critical to improving patient outcomes. To develop and enhance this chain of survival, measuring and monitoring the resuscitation processes and outcomes are essential for quality assurance. In Japan, several OHCA registries have successfully been implemented at both local and national levels. We aimed to review and summarise the conception, strengths, and challenges of OHCA registries in Japan.

Method and results

The following representing registries in Japan were reviewed: the All-Japan Utstein registry, the Utstein Osaka Project/the Osaka-CRITICAL study, the SOS-KANTO study, the JAAM-OHCA study, and the SAVE-J II study. The All-Japan Utstein registry, operated by the Fire and Disaster Management Agency of Japan and one of the largest nationwide population-based registries in the world, collects data concerning all patients with OHCA in Japan, excluding in-hospital data. Other research- and hospital-based registries collect detailed out-of-hospital and in-hospital data. The Osaka-CRITICAL study and the SOS-KANTO study are organized at regional levels, and hospitals in the Osaka prefecture and in the Kanto area participate in these registries. The JAAM-OHCA study is managed by the Japanese Association of Acute Medicine and includes 107 hospitals throughout Japan. The Save-J II study focuses on patients with OHCA treated with extracorporeal cardiopulmonary resuscitation.

Conclusion

Each OHCA registry has its own philosophy, strengths, perspectives, and challenges; however, all have been successful in contributing to the improvement of emergency medical service (EMS) systems through the quality improvement process. These registries are expected to be further utilized to enhance EMS systems and improve outcomes for patients with OHCA, while also contributing to the field of resuscitation science.

Association between prehospital time and in-hospital outcomes in out-of-hospital cardiac arrests according to resuscitation outcomes consortium epidemiologic registry

INTRODUCTION

For out-of-hospital cardiac arrests (OHCAs), time is of the essence. While the relationship between EMS response time (ERT) and OHCA outcomes is well studied, a more comprehensive assessment of the effects of other intervention time is needed, which is essential to guide clinical practice.

OBJECTIVES

Evaluating how a longer total pre-hospital time (TPT), ERT, advance life support response time (ART) and EMS cardiopulmonary resuscitation time (ECT) increase the mortality rates, unfavorable neurological outcomes, and severe complications at discharge of OHCAs.

METHODS

31,926 OHCAs from the USA and Canada were identified in Resuscitation Outcomes Consortium Epidemiologic Registry. Twelve adjusted models were used to analyze the relationship between the prehospital time (TPT, ERT, ART and ECT) and three outcomes (in hospital mortality, unfavorable neurological outcomes, and severe complications for surviving OHCAs).

RESULTS

Every 10-min increase in TPT was associated with a 0.14-fold increase in the risk of death (adjusted odds ratio [OR] = 1.14, 95 % confidence interval [CI] = 1.10-1.17) and a 0.13-fold increase of adverse neurological outcomes (OR = 1.13, CI =1.08-1.18). The risk of patient mortality markedly increased with every 5 min increase in ERT (OR = 1.36, CI = 1.26-1.47), ART (OR =1.10, CI = 1.06-1.15), and ECT (OR = 1.46, CI = 1.37-1.56). Adverse neurological outcome was associated with ERT and ECT, and severe complications with ERT and ART.

CONCLUSION

Prolonged prehospital time, particularly ERT and ECT, are closely associated with in-hospital mortality, unfavorable neurological functions, and severe complications at discharge in OHCAs.

Changes Over 7 Years in Temperature Control Treatment and Outcomes After Out-of-Hospital Cardiac Arrest: A Japanese, Multicenter Cohort Study

Temperature control is the only neuroprotective intervention suggested in current international guidelines for patients with return of spontaneous circulation after cardiac arrest, but the prevalence of temperature control therapy, temperature settings, and outcomes have not been clearly reported. We aimed to investigate changes over 7 years in provision of temperature control treatment among out-of-hospital cardiac arrest (OHCA) patients in Kanto region, Japan. Data of all adult OHCA patients who survived for more than 24 hours in the prospective cohort studies, SOS-KANTO 2012 (conducted from 2012 to 2013) and SOS-KANTO 2017 (conducted from 2019 to 2021), in Japan were included. We compared the prevalence of temperature control and the proportion of mild (≥35°C) and moderate (from 32°C to 34.9°C) hypothermia between the two study groups. We also performed a Cox regression analysis to evaluate 30-day mortality adjusted by temperature control therapy (none, moderate hypothermia, or mild hypothermia), age, sex, past medical history, witnessed status, bystander cardiopulmonary resuscitation, initial rhythm, location of arrest, and dataset (SOS-KANTO 2012 or 2017). We analyzed data from 2936 patients (n = 1710, SOS-KANTO 2012; n = 1226, SOS-KANTO 2017). Use of temperature control was lower (45.3% vs. 41.4%, p = 0.04), moderate hypothermia was lower (p < 0.01), and mild hypothermia was higher (p < 0.01) in SOS-KANTO 2017 compared with SOS-KANTO 2012. The survival rate was significantly higher for patients with mild (p < 0.01) and moderate (p < 0.01) hypothermia compared with those who did not receive temperature control therapy. Overall, the incidence of moderate hypothermia decreased and that of mild hypothermia increased and the use of temperature control decreased between the two studies conducted 7 years apart in the Kanto area, Japan. Temperature control management might improve survival of patients with OHCA.

Online platform for cardiopulmonary resuscitation and automated external defibrillator training in a rural area: a community clinical trial protocol

INTRODUCTION

Sudden death resulting from cardiorespiratory arrest carries a high mortality rate and frequently occurs out of hospital. Immediate initiation of cardiopulmonary resuscitation (CPR) by witnesses, combined with automated external defibrillator (AED) use, has proven to double survival rates. Recognising the challenges of timely emergency services in rural areas, the implementation of basic CPR training programmes can improve survival outcomes. This study aims to evaluate the effectiveness of online CPR-AED training among residents in a rural area of Tarragona, Spain.

METHODS

Quasi-experimental design, comprising two phases. Phase 1 involves assessing the effectiveness of online CPR-AED training in terms of knowledge acquisition. Phase 2 focuses on evaluating participant proficiency in CPR-AED simulation manoeuvres at 1 and 6 months post training. The main variables include the score difference between pre-training and post-training test (phase 1) and the outcomes of the simulated test (pass/fail; phase 2). Continuous variables will be compared using Student's t-test or Mann-Whitney U test, depending on normality. Pearson's χ2 test will be applied for categorical variables. A multivariate analysis will be conducted to identify independent factors influencing the main variable.

ETHICS AND DISSEMINATION

This study adheres to the tenets outlined in the Declaration of Helsinki and of Good Clinical Practice. It operated within the Smartwatch project, approved by the Clinical Research Ethics Committee of the Primary Care Research Institute IDIAP Jordi Gol i Gurina Foundation, code 23/081-P. Data confidentiality aligns with Spanish and European Commission laws for the protection of personal data. The study's findings will be published in peer-reviewed journals and presented at scientific meetings.

TRIAL REGISTRATION NUMBER

NCT05747495.

Lower versus higher oxygen targets after resuscitation from out-of-hospital cardiac arrest: A systematic review and meta-analysis of randomized controlled trials

PURPOSE

To update the existing evidence and gain further insight into effects of lower versus higher oxygen targets on the outcomes in patients resuscitated from out-of-hospital cardiac arrest (OHCA).

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing lower versus higher oxygen targets on the outcomes among adults resuscitated from OHCA. The primary outcome was short-term survival (in hospital or within 30 days). Subgroup analyses were performed according to timing of study interventions.

RESULTS

Seven RCTs with 1454 patients were finally included. The short-term survival did not differ between the two groups with a relative risk (RR) of 0.98 (95% CI, 0.86 to 1.11). There were no significant differences in survival at longest follow-up (RR, 1.01; 95% CI, 0.91 to 1.14), favorable neurological outcome (RR, 1.00; 95% CI, 0.91 to 1.11), length of intensive care unit stay (mean difference, -4.94 h; 95% CI, -14.83 to 4.96 h), or risk of re-arrest (RR, 0.68; 95% CI, 0.21 to 2.19). The quality of evidence ranged from moderate to very low.

CONCLUSION

Current evidence suggests that targeting a lower or higher oxygen therapy in patients after resuscitation from OHCA results in similar short-term survival and other clinical outcomes.

Temporal elevation of blood pressure is associated with increased risk of sudden cardiac arrest

Hypertension is a known risk factor for sudden cardiac arrest (SCA). However, the role of temporal changes in blood pressure on the risk of SCA is not fully understood. This study was conducted to determine whether a temporal increase or decrease in blood pressure is associated with the risk of SCA. This study was based on nationwide healthcare insurance data. Individuals who underwent nationwide health check-ups in 2009 and 2011 were analyzed. A total of 2,801,153 individuals were evaluated for 8100 SCA events during the 17, 740, 420 person-years of follow-up. In a multivariate analysis, there were linear association between the degree of temporal elevation of systolic blood pressure (SBP) and the risk of SCA: (i) adjusted-hazard ratio (HR) 1.11 (p = 0.001) in 10 ≤ ΔSBP < 20 (mmHg) group; (ii) adjusted-HR 1.40 (p < 0.001) in 20 ≤ ΔSBP < 40 group; and (iii) adjusted-HR 1.88 (p < 0.001) in 40 ≤ ΔSBP group as compared with the reference group (- 10 ≤ ΔSBP < 10). Temporal increase in diastolic blood pressure (DBP) also a showed significant association with SCA risk with the highest risk observed in ∆DBP ≥ 25 group (adjusted-HR 1.61; p < 0.001) as compared with the reference group (- 5 ≤ ΔDBP < 5). The association between SBP and SCA was not affected by age, sex, presence of diabetes mellitus, or baseline SBP. In conclusion, a temporal increase in blood pressure was significantly associated with the occurrence of SCA, and this association was consistent across all subgroups. However, a temporary decrease in blood pressure does not reduce the risk of SCA. Prevention of elevated blood pressure may play an important role in preventing SCA.

A locally optimised machine learning approach to early prognostication of long-term neurological outcomes after out-of-hospital cardiac arrest

Background

Out-of-hospital cardiac arrest (OHCA) represents a major burden for society and health care, with an average incidence in adults of 67 to 170 cases per 100,000 person-years in Europe and in-hospital survival rates of less than 10%. Patients and practitioners would benefit from a prognostication tool for long-term good neurological outcomes.

Objective

We aim to develop a machine learning (ML) pipeline on a local database to classify patients according to their neurological outcomes and identify prognostic features.

Methods

We collected clinical and biological data consecutively from 595 patients who presented OHCA and were routed to a single regional cardiac arrest centre in the south of France. We applied recursive feature elimination and ML analyses to identify the main features associated with a good neurological outcome, defined as a Cerebral Performance Category score less than or equal to 2 at six months post-OHCA.

Results

We identified 12 variables 24 h after admission, capable of predicting a six-month good neurological outcome. The best model (extreme gradient boosting) achieved an AUC of 0.96 and an accuracy of 0.92 in the test cohort.

Conclusion

We demonstrated that it is possible to build accurate, locally optimised prediction and prognostication scores using datasets of limited size and breadth. We proposed and shared a generic machine-learning pipeline which allows external teams to replicate the approach locally.

Impact of the COVID-19 pandemic on Canadian emergency medical system management of out-of-hospital cardiac arrest: A retrospective cohort study

AIM

We sought to describe the impact of the COVID-19 pandemic on the care provided by Canadian emergency medical system (EMS) clinicians to patients suffering out of hospital cardiac arrest (OHCA), and whether any observed changes persisted beyond the initial phase of the pandemic.

METHODS

We analysed cases of adult, non-traumatic, OHCA from the Canadian Resuscitation Outcome Consortium (CanROC) registry who were treated between January 27th, 2018, and December 31st, 2021. We used adjusted regression models and interrupted time series analysis to examine the impact of the COVID-19 pandemic (January 27th, 2020 - December 31st, 2021)on the care provided to patients with OHCA by EMS clinicians.

RESULTS

There were 12,947 cases of OHCA recorded in the CanROC registry in the pre-COVID-19 period and 17,488 during the COVID-19 period. We observed a reduction in the cumulative number of defibrillations provided by EMS (aRR 0.91, 95% CI 0.89 - 0.93, p < 0.01), a reduction in the odds of attempts at intubation (aOR 0.33, 95% CI 0.31 - 0.34, p < 0.01), higher rates of supraglottic airway use (aOR 1.23, 95% CI 1.16-1.30, p < 0.01), a reduction in vascular access (aOR for intravenous access 0.84, 95% CI 0.79 - 0.89, p < 0.01; aOR for intraosseous access 0.89, 95% CI 0.82 - 0.96, p < 0.01), a reduction in the odds of epinephrine administration (aOR 0.89, 95% CI 0.85 - 0.94, p < 0.01), and higher odds of resuscitation termination on scene (aOR 1.38, 95% CI 1.31 - 1.46, p < 0.01). Delays to initiation of chest compressions (2 min. vs. 3 min., p < 0.01), intubation (16 min. vs. 19 min., p = 0.01), and epinephrine administration (11 min. vs. 13 min., p < 0.01) were observed, whilst supraglottic airways were inserted earlier (11 min. vs. 10 min., p < 0.01).

CONCLUSION

The COVID-19 pandemic was associated with substantial changes in EMS management of OHCA. EMS leaders should consider these findings to optimise current OHCA management and prepare for future pandemics.

Implementation and use of a supraglottic airway device in the management of out-of-hospital cardiac arrest by firefighter first responders - A prospective feasibility study

Aim

We wanted to assess the implementation and use of a supraglottic airway (SGA) for on-call firefighter first responders in out-of-hospital cardiac arrest.

Methods

We trained 502 firefighter first responders, located at 35 fire stations in the South-East of Norway, in the use of SGA during cardiopulmonary resuscitation in adult out-of-hospital cardiac arrest. Training consisted of 45 minutes of theoretical and practical training in small groups.Primary outcome was successful ventilation with SGA assessed by both firefighter first responders and first paramedic arriving on-scene. Secondary outcomes included time expenditure and complications related to the procedure, evaluation of the training, and descriptive characteristics of the out-of-hospital cardiac arrest cases.

Results

An SGA was used by firefighter first responders in 23 out-of-hospital cardiac arrests, and successful ventilation was achieved in 20 (87%) cases. Air-leak was described in the three unsuccessful cases. The median procedural time was 30 seconds (IQR = 15-40), with no observed procedural complications. Firefighter first responders arrived in median time 9 minutes (IQR = 6-10 min) before the ambulance. They performed chest compressions on all patients and 6 (26%) of the patients received shock with semi-automatic external defibrillator. After training, all participants were able to successfully ventilate a manikin with the SGA. The cost of the SGA equipment for all fire stations was 3955 GBP.

Conclusion

Implementation of an SGA for firefighter first responders in out-of-hospital cardiac arrest management seems feasible, safe and can be introduced with limited amount of training and limited use of resources.

Assessment of Basic Life Support Knowledge Among Medical Students in Jordan: Implications for Improving Out-of-Hospital Cardiac Arrest and Road Traffic Accident Survival Rates

This study aimed to assess the level of basic life support (BLS) knowledge among fifth- and sixth-year medical students in Jordan, identify differences in knowledge levels between male and female students and between different universities, and provide insights into the current status of BLS training in medical education in Jordan. The study had 570 respondents, with females constituting 61.1% of the sample. The total average score for medical students was 12.24/17 (72%), and there was a considerable variation in the response rate between universities. The study found that students whose source of knowledge was previous college courses had the highest mean score, and only 24.9% knew the proper position of both hands while doing chest compressions. The study underscores the importance of adequate BLS training for healthcare providers to improve survival rates and reduce mortality and morbidity associated with out-of-hospital cardiac arrest and road traffic accidents. The findings of this study could inform future interventions aimed at improving BLS knowledge and skills.

Wolf Creek XVII Part 5: Mobile AEDs

Introduction

Millions of out-of-hospital cardiac arrests (OHCA) occur globally each year. Survival after OHCA can be improved with the use of automated external defibrillators (AED). The main strategy for facilitating bystander defibrillation has been fixed-location public access defibrillators (PADs). New strategies of mobile AEDs depart from the model of static PADs and have the potential to address known barriers to early defibrillation and improve outcomes.

Methods

Mobile AEDs was one of six focus topics for the Wolf Creek XVII Conference held on June 14-17, 2023, in Ann Arbor, Michigan, USA. Conference invitees included international thought leaders and scientists in the field of cardiac arrest resuscitation from academia and industry. Participants submitted via online survey knowledge gaps, barriers to translation and research priorities for each focus topic. Expert panels used the survey results and their own perspectives and insights to create and present a preliminary unranked list for each category that was debated, revised, and ranked by all attendees to identify the top 5 for each category.

Results

Top knowledge gaps center around understanding the impact of mobile AEDs on OHCA outcomes in various settings and the impact of novel AED technologies. Top barriers to translation include questionable public comfort/acceptance, financial/regulatory constraints, and a lack of centralized accountability. Top research priorities focus on understanding the impact of the mobile AED strategies and technologies on time to defibrillation and OHCA outcomes.

Conclusion

This work informs research agendas, funding priorities and policy decisions around using mobile AEDs to optimize prehospital response to OHCA.

Machine learning pre-hospital real-time cardiac arrest outcome prediction (PReCAP) using time-adaptive cohort model based on the Pan-Asian Resuscitation Outcome Study

To save time during transport, where resuscitation quality can degrade in a moving ambulance, it would be prudent to continue the resuscitation on scene if there is a high likelihood of ROSC occurring at the scene. We developed the pre-hospital real-time cardiac arrest outcome prediction (PReCAP) model to predict ROSC at the scene using prehospital input variables with time-adaptive cohort. The patient survival at discharge from the emergency department (ED), the 30-day survival rate, and the final Cerebral Performance Category (CPC) were secondary prediction outcomes in this study. The Pan-Asian Resuscitation Outcome Study (PAROS) database, which includes out-of-hospital cardiac arrest (OHCA) patients transferred by emergency medical service in Asia between 2009 and 2018, was utilized for this study. From the variables available in the PAROS database, we selected relevant variables to predict OHCA outcomes. Light gradient-boosting machine (LightGBM) was used to build the PReCAP model. Between 2009 and 2018, 157,654 patients in the PAROS database were enrolled in our study. In terms of prediction of ROSC on scene, the PReCAP had an AUROC score between 0.85 and 0.87. The PReCAP had an AUROC score between 0.91 and 0.93 for predicting survived to discharge from ED, and an AUROC score between 0.80 and 0.86 for predicting the 30-day survival. The PReCAP predicted CPC with an AUROC score ranging from 0.84 to 0.91. The feature importance differed with time in the PReCAP model prediction of ROSC on scene. Using the PAROS database, PReCAP predicted ROSC on scene, survival to discharge from ED, 30-day survival, and CPC for each minute with an AUROC score ranging from 0.8 to 0.93. As this model used a multi-national database, it might be applicable for a variety of environments and populations.

Outcomes of out-of-hospital cardiac arrest in Ireland 2012-2020: Protocol for an observational study

Background

Out-of-hospital cardiac arrest (OHCA) is a leading cause of preventable mortality that now affects almost 3,000 people each year in Ireland. Survival is low at 6-7%, compared to a European average of 8%. The Irish Out-of-Hospital Cardiac Registry (OHCAR) prospectively gathers data on all OHCA in Ireland where emergency medical services attempted resuscitation.The Irish health system has undergone several developments that are relevant to OHCA care in the period 2012-2020. OHCAR data provides a means of exploring temporal trends in OHCA incidence, care, and outcomes over time. It also provides a means of exploring whether system developments were associated with a change in key outcomes.This research aims to summarise key trends in available OHCAR data from the period 2012 - 2020, to explore and model predictors of bystander CPR, bystander defibrillation, and survival, and to explore the hypothesis that significant system level temporal developments were associated with improvements in these outcomes.

Methods

The following protocol sets out the relevant background and research approach for an observational study that will address the above aims. Key trends in available OHCAR data (2012 - 2020) will be described and evaluated using descriptive summaries and graphical displays. Multivariable logistic regression will be used to model predictors of 'bystander CPR', 'bystander defibrillation' and 'survival to hospital discharge' and to explore the effects (if any) of system level developments in 2015/2016 and the COVID-19 pandemic (2020) on these outcomes.

Discussion

The findings of this research will be used to understand temporal trends in the care processes and outcomes for OHCA in Ireland over the period 2012-2020. The results can further be used to optimise future health system developments for OHCA in both Ireland and internationally.

Outcome assessment for out-of-hospital cardiac arrest patients in Singapore and Japan with initial shockable rhythm

BACKGROUND

Singapore and Osaka in Japan have comparable population sizes and prehospital management; however, the frequency of ECPR differs greatly for out-of-hospital cardiac arrest (OHCA) patients with initial shockable rhythm. Given this disparity, we hypothesized that the outcomes among the OHCA patients with initial shockable rhythm in Singapore were different from those in Osaka. The aim of this study was to evaluate the outcomes of OHCA patients with initial shockable rhythm in Singapore compared to the expected outcomes derived from Osaka data using machine learning-based prediction models.

METHODS

This was a secondary analysis of two OHCA databases: the Singapore PAROS database (SG-PAROS) and the Osaka-CRITICAL database from Osaka, Japan. This study included adult (18-74 years) OHCA patients with initial shockable rhythm. A machine learning-based prediction model was derived and validated using data from the Osaka-CRITICAL database (derivation data 2012-2017, validation data 2018-2019), and applied to the SG-PAROS database (2010-2016 data), to predict the risk-adjusted probability of favorable neurological outcomes. The observed and expected outcomes were compared using the observed-expected ratio (OE ratio) with 95% confidence intervals (CI).

RESULTS

From the SG-PAROS database, 1,789 patients were included in the analysis. For OHCA patients who achieved return of spontaneous circulation (ROSC) on hospital arrival, the observed favorable neurological outcome was at the same level as expected (OE ratio: 0.905 [95%CI: 0.784-1.036]). On the other hand, for those who had continued cardiac arrest on hospital arrival, the outcomes were lower than expected (shockable rhythm on hospital arrival, OE ratio: 0.369 [95%CI: 0.258-0.499], and nonshockable rhythm, OE ratio: 0.137 [95%CI: 0.065-0.235]).

CONCLUSION

This observational study found that the outcomes for patients with initial shockable rhythm but who did not obtain ROSC on hospital arrival in Singapore were lower than expected from Osaka. We hypothesize this is mainly due to differences in the use of ECPR.

Impact of pre-hospital handling and initial time to cranial computed tomography on outcome in aneurysmal subarachnoid hemorrhage patients with out-of-hospital sudden cardiac arrest-a retrospective bi-centric study

Background

Aneurysmal subarachnoid hemorrhage (SAH) presents occasionally with cardiac arrest (CA). The impact of pre-hospital and emergency room (ER) treatment on outcome remains unclear. Therefore, we investigated the impact of pre-hospital treatment, focusing on lay cardiopulmonary resuscitation (CPR), and ER handling on the outcome of SAH patients with out-of-hospital CA (OHCA).

Methods

In this bi-centric retrospective analysis, we reviewed SAH databases for OHCA and CPR from January 2011 to June 2021. Patients were analyzed for general clinical and epidemiological parameters. CPR data were obtained from ambulance reports and information on ER handling from the medical records. Data were correlated with patient survival at hospital discharge as a predefined outcome parameter.

Results

Of 1,120 patients with SAH, 45 (4.0%) were identified with OHCA and CPR, 38 of whom provided all required information and were included in this study. Time to resuscitation was significantly shorter with lay resuscitation (5.3 ± 5.2 min vs. 0.3 ± 1.2 min, p = 0.003). Nineteen patients were not initially scheduled for cranial computed tomography (CCT), resulting in a significantly longer time interval to first CCT (mean ± SD: 154 ± 217 min vs. 40 ± 23 min; p < 0.001). Overall survival to discharge was 31.6%. Pre-hospital lay CPR was not associated with higher survival (p = 0.632). However, we observed a shorter time to first CCT in surviving patients (p = 0.065).

Conclusions

OHCA in SAH patients is not uncommon. Besides high-quality CPR, time to diagnosis of SAH appears to play an important role. We therefore recommend considering CCT diagnostics as part of the diagnostic algorithm in patients with OHCA.

Out-of-hospital cardiac arrest: A data-driven visualization of collaboration, frontier identification, and future trends

One of the main causes of death is out-of-hospital cardiac arrest (OHCA), which has a poor prognosis and poor neurological outcomes. This phenomenon has attracted increasing attention. However, there is still no published bibliometric analysis of OHCA. This bibliometric analysis of publications on OHCA aimed to visualize the current status of research, determine the frontiers of research, and identify future trends. Publications on OHCA were downloaded from the web of science database. The data elements included year, countries/territories, institutions, authors, journals, research areas, citations of publications, etc. Joinpoint regression and exponential models were used to identify and predict the trend of publications, respectively. Knowledge domain maps were applied to conduct contribution and collaboration, cooccurrence, cocitation, and coupled analyses. Timeline and burst detection analysis were used to identify the frontiers in the field. A total of 3 219 publications on OHCA were found from 1998 to 2022 (average annual percentage change = 16.7; 95% CI 14.4, 19.1). It was estimated that 859 articles and reviews would be published in 2025. The following research hotpots were identified: statement, epidemiology, clinical care, factors influencing prognosis and emergency medical services. The research frontier identification revealed that 7 categories were classified, including therapeutic hypothermia, emergency medical services, airway management, myocardial infarction, extracorporeal cardiopulmonary resuscitation, stroke foundation and trial. The burst detection analysis revealed that percutaneous coronary intervention, neurologic outcome, COVID-19 and extracorporeal cardiopulmonary resuscitation are issues that should be given continual attention in the future. This bibliometric analysis may reflect the current status and future frontiers of OHCA research.

Epinephrine in Out-of-Hospital Cardiac Arrest: A Network Meta-analysis and Subgroup Analyses of Shockable and Nonshockable Rhythms

BACKGROUND

Epinephrine is the most commonly used drug in out-of-hospital cardiac arrest (OHCA) resuscitation, but evidence supporting its efficacy is mixed.

RESEARCH QUESTION

What are the comparative efficacy and safety of standard dose epinephrine, high-dose epinephrine, epinephrine plus vasopressin, and placebo or no treatment in improving outcomes after OHCA?

STUDY DESIGN AND METHODS

In this systematic review and network meta-analysis of randomized controlled trials, we searched six databases from inception through June 2022 for randomized controlled trials evaluating epinephrine use during OHCA resuscitation. We performed frequentist random-effects network meta-analysis and present ORs and 95% CIs. We used the the Grading of Recommendations, Assessment, Development, and Evaluation approach to rate the certainty of evidence. Outcomes included return of spontaneous circulation (ROSC), survival to hospital admission, survival to discharge, and survival with good functional outcome.

RESULTS

We included 18 trials (21,594 patients). Compared with placebo or no treatment, high-dose epinephrine (OR, 4.27; 95% CI, 3.68-4.97), standard-dose epinephrine (OR, 3.69; 95% CI, 3.32-4.10), and epinephrine plus vasopressin (OR, 3.54; 95% CI, 2.94-4.26) all increased ROSC. High-dose epinephrine (OR, 3.53; 95% CI, 2.97-4.20), standard-dose epinephrine (OR, 3.00; 95% CI, 2.66-3.38), and epinephrine plus vasopressin (OR, 2.79; 95% CI, 2.27-3.44) all increased survival to hospital admission as compared with placebo or no treatment. However, none of these agents may increase survival to discharge or survival with good functional outcome as compared with placebo or no treatment. Compared with placebo or no treatment, standard-dose epinephrine improved survival to discharge among patients with nonshockable rhythm (OR, 2.10; 95% CI, 1.21-3.63), but not in those with shockable rhythm (OR, 0.85; 95% CI, 0.39-1.85).

INTERPRETATION

Use of standard-dose epinephrine, high-dose epinephrine, and epinephrine plus vasopressin increases ROSC and survival to hospital admission, but may not improve survival to discharge or functional outcome. Standard-dose epinephrine improved survival to discharge among patients with nonshockable rhythm, but not those with shockable rhythm.

TRIAL REGISTRY

Center for Open Science: https://osf.io/arxwq.

Tele-Instruction Tool for Multiple Lay Responders Providing Cardiopulmonary Resuscitation in Telehealth Emergency Dispatch Services: Mixed Methods Study

BACKGROUND

Telephone-assisted cardiopulmonary resuscitation (T-CPR) has proven to be a crucial intervention in enhancing the ability of lay responders to perform cardiopulmonary resuscitation (CPR) during telehealth emergency services. While the majority of established T-CPR protocols primarily focus on guiding individual rescuers, there is a lack of emphasis on instructing and coordinating multiple lay responders to perform resuscitation collaboratively.

OBJECTIVE

This study aimed to develop an innovative team-based tele-instruction tool to efficiently organize and instruct multiple lay responders on the CPR process and to evaluate the effectiveness and feasibility of the tool.

METHODS

We used a mixed methods design in this study. We conducted a randomized controlled simulation trial to conduct the quantitative analysis. The intervention groups used the team-based tele-instruction tool for team resuscitation, while the control groups did not have access to the tool. Baseline resuscitation was performed during the initial phase (phase I test). Subsequently, all teams watched a team-based CPR education training video and finished a 3-person practice session with teaching followed by a posttraining test (phase II test). In the qualitative analysis, we randomly selected an individual from each team and 4 experts in emergency medical services to conduct semistructured interviews. The purpose of these interviews was to evaluate the effectiveness and feasibility of this tool.

RESULTS

The team-based tele-instruction tool significantly improved the quality of chest compression in both phase I and phase II tests. The average compression rates were more appropriate in the intervention groups compared to the control groups (median 104.5, IQR 98.8-111.8 min-1 vs median 112, IQR 106-120.8 min-1; P=.04 in phase I and median 117.5, IQR 112.3-125 min-1 vs median 111, IQR 105.3-119 min-1; P=.03 in phase II). In the intervention group, there was a delay in the emergency response time compared to that in the control group (time to first chest compression: median 20, IQR 15-24.8 seconds vs median 25, IQR 20.5-40.3 seconds; P=.03; time to open the airway: median 48, IQR 36.3-62 seconds vs median 73.5, IQR 54.5-227.8 seconds; P=.01). However, this delay was partially mitigated after the phase II test. The qualitative results confirmed the compatibility and generalizability of the team-based tele-instruction tool, demonstrating its ability to effectively guide multiple lay responders through teamwork and effective communication with telecommunicators.

CONCLUSIONS

The use of the team-based tele-instruction tool offers an effective solution to enhance the quality of chest compression among multiple lay responders. This tool facilitated the organization of resuscitation teams by dispatchers and enabled efficient cooperation. Further assessment of the widespread adoption and practical application of the team-based tele-instruction tools in real-life rescue scenarios within the telehealth emergency services system is warranted.

More than 302 million people reached and over 2,200,000 trained in cardiopulmonary resuscitation worldwide: The 2021 ILCOR World Restart a Heart initiative

Immediate bystander CPR after an out-of-hospital-cardiac arrest is likely to save hundreds of thousands of lives worldwide each year. International Liaison Committee on Resuscitation launched the World Restart a Heart initiative on October 16, 2018. In 2021 more than 2,200,000 persons were trained and at least 302,000,000 people were reached by WRAH global collaboration through print and digital media making it the highest-impact year since its inception. We strive for real success when CPR training and awareness become a year-round activity in all countries and all the citizens of the world realize that "Two Hands Can Save a Life!"

The development of a risk-adjustment strategy to benchmark emergency medical service (EMS) performance in relation to out-of-hospital cardiac arrest in Australia and New Zealand

INTRODUCTION

The aim of this study was to develop a risk adjustment strategy, including effect modifiers, for benchmarking emergency medical service (EMS) performance for out-of-hospital cardiac arrest (OHCA) in Australia and New Zealand.

METHOD

Using 2017-2019 data from the Australasian Resuscitation Outcomes Consortium (Aus-ROC) OHCA Epistry, we included adults who received an EMS attempted resuscitation for a presumed medical OHCA. Logistic regression was applied to develop risk adjustment models for event survival (return of spontaneous circulation at hospital handover) and survival to hospital discharge/30 days. We examined potential effect modifiers, and assessed model discrimination and validity.

RESULTS

Both OHCA survival outcome models included EMS agency and the Utstein variables (age, sex, location of arrest, witnessed arrest, initial rhythm, bystander cardiopulmonary resuscitation, defibrillation prior to EMS arrival, and EMS response time). The model for event survival had good discrimination according to the concordance statistic (0.77) and explained 28% of the variation in survival. The corresponding figures for survival to hospital discharge/30 days were 0.87 and 49%. The addition of effect modifiers did little to improve the performance of either model.

CONCLUSION

The development of risk adjustment models with good discrimination is an important step in benchmarking EMS performance for OHCA. The Utstein variables are important in risk-adjustment, but only explain a small proportion of the variation in survival. Further research is required to understand what factors contribute to the variation in survival between EMS.

Comparison of out-of-hospital cardiac arrests during the COVID-19 pandemic with those before the pandemic: an updated systematic review and meta-analysis

The coronavirus disease of 2019 (COVID-19) pandemic, directly and indirectly, affected the emergency medical care system and resulted in worse out-of-hospital cardiac arrest (OHCA) outcomes and epidemiological features compared with those before the pandemic. This review compares the regional and temporal features of OHCA prognosis and epidemiological characteristics. Various databases were searched to compare the OHCA outcomes and epidemiological characteristics during the COVID-19 pandemic with before the pandemic. During the COVID-19 pandemic, survival and favorable neurological outcome rates were significantly lower than before. Survival to hospitalization, return of spontaneous circulation, endotracheal intubation, and use of an automated external defibrillator (AED) decreased significantly, whereas the use of a supraglottic airway device, the incidence of cardiac arrest at home, and response time of emergency medical service (EMS) increased significantly. Bystander CPR, unwitnessed cardiac arrest, EMS transfer time, use of mechanical CPR, and in-hospital target temperature management did not differ significantly. A subgroup analysis of the studies that included only the first wave with those that included the subsequent waves revealed the overall outcomes in which the epidemiological features of OHCA exhibited similar patterns. No significant regional differences between the OHCA survival rates in Asia before and during the pandemic were observed, although other variables varied by region. The COVID-19 pandemic altered the epidemiologic characteristics, survival rates, and neurological prognosis of OHCA patients. Review registration: PROSPERO (CRD42022339435).

Association of Prehospital Physician Presence During Pediatric Out-of-Hospital Cardiac Arrest With Neurologic Outcomes

OBJECTIVES

To examine the association of prehospital physician presence with neurologic outcomes of pediatric patients with out-of-hospital cardiac arrest (OHCA).

DESIGN

Retrospective cohort study.

SETTING

Data from the Japanese Association for Acute Medicine-OHCA Registry.

INTERVENTIONS

None.

PATIENTS

Pediatric patients (age 17 yr old or younger) registered in the database between June 2014 and December 2019.

MEASUREMENT AND MAIN RESULTS

We used logistic regression models with stabilized inverse probability of treatment weighting (IPTW) to estimate the associated treatment effect of a prehospital physician with 1-month neurologically intact survival. Secondary outcomes included in-hospital return of spontaneous circulation (ROSC) and 1-month survival after OHCA. A total of 1,187 patients (276 in the physician presence group and 911 in the physician absence group) were included (median age 3 yr [interquartile range 0-14 yr]; 723 [61%] male). Comparison of the physician presence group, versus the physician absence, showed 1-month favorable neurologic outcomes of 8.3% (23/276) versus 3.6% (33/911). Physician presence was associated with greater odds of 1-month neurologically intact survival after stabilized IPTW adjustment (adjusted odds ratio [aOR] 1.98, 95% CI 1.08-3.66). We also found an association in the secondary outcome between physician presence, opposed to absence, and in-hospital ROSC (aOR 1.48, 95% CI 1.08-2.04). However, we failed to identify an association with 1-month survival (aOR 1.49, 95% CI 0.97-2.88).

CONCLUSIONS

Among pediatric patients with OHCA, prehospital physician presence, compared with absence, was associated almost two-fold greater odds of 1-month favorable neurologic outcomes.

Obesity Is Indirectly Associated with Sudden Cardiac Arrest through Various Risk Factors

Although obesity is a well-established risk factor of cardiovascular event, the linkage between obesity and sudden cardiac arrest (SCA) is not fully understood. Based on a nationwide health insurance database, this study investigated the impact of body weight status, measured by body-mass index (BMI) and waist circumference, on the SCA risk. A total of 4,234,341 participants who underwent medical check-ups in 2009 were included, and the influence of risk factors (age, sex, social habits, and metabolic disorders) was analyzed. For 33,345,378 person-years follow-up, SCA occurred in 16,352 cases. The BMI resulted in a J-shaped association with SCA risk, in which the obese group (BMI ≥ 30) had a 20.8% increased risk of SCA compared with the normal body weight group (18.5 ≤ BMI < 23.0) (p < 0.001). Waist circumference showed a linear association with the risk of SCA, with a 2.69-fold increased risk of SCA in the highest waist circumference group compared with the lowest waist circumference group (p < 0.001). However, after adjustment of risk factors, neither BMI nor waist circumference was associated with the SCA risk. In conclusion, obesity is not independently associated with SCA risk based on the consideration of various confounders. Rather than confining the findings to obesity itself, comprehensive consideration of metabolic disorders as well as demographics and social habits might provide better understanding and prevention of SCA.

Improving vasopressor use in cardiac arrest

The Chain of Survival highlights the effectiveness of early recognition of cardiac arrest and call for help, early cardiopulmonary resuscitation and early defibrillation. Most patients, however, remain in cardiac arrest despite these interventions. Drug treatments, particularly the use of vasopressors, have been included in resuscitation algorithms since their inception. This narrative review describes the current evidence base for vasopressors and reports that adrenaline (1 mg) is highly effective at achieving return of spontaneous circulation (number needed to treat 4) but is less effective on long-term outcomes (survival to 30 days, number needed to treat 111) with uncertain effects on survival with a favourable neurological outcome. Randomised trials evaluating vasopressin, either as an alternative to or in addition to adrenaline, and high-dose adrenaline have failed to find evidence of improved long-term outcomes. There is a need for future trials to evaluate the interaction between steroids and vasopressin. Evidence for other vasopressors (e.g. noradrenaline, phenylephedrine) is insufficient to support or refute their use. The use of intravenous calcium chloride as a routine intervention in out of hospital cardiac arrest is not associated with benefit and may cause harm. The optimal route for vascular access between peripheral intravenous versus intraosseous routes is currently the subject of two large randomised trials. Intracardiac, endobronchial, and intramuscular routes are not recommended. Central venous administration should be limited to patients where an existing central venous catheter is in situ and patent.

Long-term increase in fasting blood glucose is associated with increased risk of sudden cardiac arrest

BACKGROUND

Diabetes mellitus (DM) is associated with various cardiovascular complications, including sudden cardiac arrest (SCA). Furthermore, the severity of DM, as assessed by fasting blood glucose (FBG), is associated with the risk of SCA. However, whether long-term changes in FBG influence on SCA risk remains to be determined.

METHODS

This study used sequential nationwide health screening data from 2009 and 2011. FBG was measured at each health screening, and ΔFBG was calculated as FBG in 2011-FBG in 2009.

RESULTS

Overall, 2,801,153 people were analyzed, and the mean follow-up duration was 6.33 years. Compared with the euglycemic group (- 20 ≤ ΔFBG < 20), the 20 ≤ ΔFBG < 40, 40 ≤ ΔFBG < 100, and ΔFBG ≥ 100 groups had increased SCA risks of 25% (adjusted hazard ratio [HR] = 1.25; 95% confidence interval [CI] 1.16-1.35; p < 0.001), 66% (adjusted HR = 1.66; 95% CI 1.49-1.86; p < 0.001), and 2.9-fold (adjusted HR = 2.85; 95% CI 2.37-3.44; p < 0.001), respectively. The association between ΔFBG and SCA was maintained in people with DM but not in people without DM. However, sex, age, blood pressure, and presence of heart failure did not affect the association between ΔFBG and SCA. A decrease in ΔFBG over time was not associated with reduced risk of SCA: the adjusted HR was 1.11 (95% CI 0.98-1.27; p = 0.113) for the ΔFBG < -40 group and 1.12 (95% CI 1.03-1.22; p = 0.009) for the - 40 ≤ ∆FBG < - 20 group.

CONCLUSIONS

A long-term increase in ΔFBG can be associated with increased risk of SCA in people with DM. However, a long-term decrease in ΔFBG was not associated with reduced risk of SCA. Actions to prevent increase in FBG can have significant effects on public health in terms of SCA prevention.

The Effect of Building-Level Socioeconomic Status on Bystander Cardiopulmonary Resuscitation: A Retrospective Cohort Study

OBJECTIVE

Understanding the social determinants of bystander cardiopulmonary resuscitation (CPR) receipt can inform the design of public health interventions to increase bystander CPR. The association of socioeconomic status with bystander CPR is generally poorly understood. We evaluated the relationship between socioeconomic status and bystander CPR in cases of out-of-hospital cardiac arrest (OHCA).

METHODS

This was a retrospective cohort study based on the Singapore cohort of the Pan-Asian Resuscitation Outcomes Study registry between 2010 and 2018. We categorized patients into low, medium, and high Singapore Housing Index (SHI) levels-a building-level index of socioeconomic status. The primary outcome was receipt of bystander CPR. The secondary outcomes were prehospital return of spontaneous circulation and survival to discharge.

RESULTS

A total of 12,730 OHCA cases were included, the median age was 71 years, and 58.9% were male. The bystander CPR rate was 56.7%. Compared to patients in the low SHI category, those in the medium and high SHI categories were more likely to receive bystander CPR (medium SHI: adjusted odds ratio [aOR] 1.48, 95% CI 1.30-1.69; high SHI: aOR 1.93, 95% CI 1.67-2.24). High SHI patients had higher survival compared to low SHI patients on unadjusted analysis (OR 1.79, 95% CI 1.08-2.96), but not adjusted analysis (adjusted for age, sex, race, witness status, arrest time, past medical history of cancer, and first arrest rhythm). When comparing high with low SHI, females had larger increases in bystander CPR rates than males.

CONCLUSIONS

Lower building-level socioeconomic status was independently associated with lower rate of bystander CPR, and females were more susceptible to the effect of low socioeconomic status on lower rate of bystander CPR.

Out-of-Hospital Cardiac Arrest during the COVID-19 Pandemic: A Systematic Review

Objective: Out-of-hospital cardiac arrest (OHCA) is a prominent cause of death worldwide. As indicated by the high proportion of COVID-19 suspicion or diagnosis among patients who had OHCA, this issue could have resulted in multiple fatalities from coronavirus disease 2019 (COVID-19) occurring at home and being counted as OHCA. Methods: We used the MeSH term "heart arrest" as well as non-MeSH terms "out-of-hospital cardiac arrest, sudden cardiac death, OHCA, cardiac arrest, coronavirus pandemic, COVID-19, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)." We conducted a literature search using these search keywords in the Science Direct and PubMed databases and Google Scholar until 25 April 2022. Results: A systematic review of observational studies revealed OHCA and mortality rates increased considerably during the COVID-19 pandemic compared to the same period of the previous year. A temporary two-fold rise in OHCA incidence was detected along with a drop in survival. During the pandemic, the community's response to OHCA changed, with fewer bystander cardiopulmonary resuscitations (CPRs), longer emergency medical service (EMS) response times, and worse OHCA survival rates. Conclusions: This study's limitations include a lack of a centralised data-gathering method and OHCA registry system. If the chain of survival is maintained and effective emergency ambulance services with a qualified emergency medical team are given, the outcome for OHCA survivors can be improved even more.

"Needed but lacked": Exploring demand- and supply-side determinants of access to cardiopulmonary resuscitation training for the lay public in China

Background

Despite years of public cardiopulmonary resuscitation (CPR) training efforts, the training rate and survival following out-of-hospital cardiac arrest (OHCA) have increased modestly in China. Access is imperative to increase the public CPR training rate, which is determined by both demand- (e.g., the lay public) and supply-side (e.g., CPR trainers) factors. We aimed to explore the demand and supply determinants of access to CPR training for the lay public in China.

Methods

Qualitative semi-structured interviews were conducted with 77 laypeople (demand side) and eight key stakeholders from CPR training institutions (supply side) in Shanghai, China. The interview guide was informed by Levesque et al. healthcare access framework. Data were transcribed, quantified, described, and analyzed through thematic content analysis.

Results

On the demand side, the laypeople's ability to perceive their need and willingness for CPR training was strong. However, they failed to access CPR training mainly due to the lack of information on where to get trained. Overestimation of skills, optimism bias, and misconceptions impeded laypeople from attending training. On the supply side, trainers were able to meet the needs of the trainees with existing resources, but they relied on participants who actively sought out and registered for training and lacked an understanding of the needs of the public for marketing and encouraging participation in the training.

Conclusion

Insufficient information and lack of initiative on the demand side, lack of motivation, and understanding of public needs on the supply side all contributed to the persistently low CPR training rate in China. Suppliers should integrate resources, take the initiative to increase the CPR training rate, innovate training modes, expand correct publicity, and establish whole-process management of training programs.

Effect of a Targeted Ambulance Treatment Quality Improvement Programme on Outcomes from Out-of-Hospital Cardiac Arrest: A Metropolitan Citywide Intervention Study

The performance of ambulance crew affects the quality of pre-hospital treatment, which is vital to the survival for out-of-hospital cardiac arrest (OHCA) patients, yet remains suboptimal in China. In this retrospective analysis study, we aimed to examine the effect of a citywide quality improvement programme on provision of prehospital advanced life support (ALS) by emergency medical service (EMS) system. EMS-treated adult OHCA patients after the implementation of the programme (1 January 2021 to 30 June 2022) were compared with historical controls (1 June 2019 to 31 August 2020) in Suzhou. Multivariable logistic regression analysis and propensity score matching procedures were applied to compare the outcomes between two periods for total OHCA cases and subgroup of cases treated by fixed or non-fixed ambulance crews. A total of 1465 patients (pre-period/post-period: 610/855) were included. In the 1:1 matched analysis of 591 cases for each period, significant improvement (p < 0.05) was observed for the proportion of intravenous (IV) access (23.4% vs. 68.2%), advanced airway management (49.2% vs. 57.0%), and return of spontaneous circulation (ROSC) at handover (5.4% vs. 9.0%). The fixed ambulance crews performed better than non-fixed group in IV access and advanced airway management for both periods. There were significant increases in IV access (AOR 12.66, 95%CI 9.02−18.10, p < 0.001), advanced airway management (AOR 1.67, 95% CI 1.30−2.16, p < 0.001) and ROSC at handover (AOR 2.37, 95%CI 1.38−4.23, p = 0.002) after intervention in unfixed group, while no significant improvement was observed in fixed group except for IV access (AOR 7.65, 95%CI 9.02−18.10, p < 0.001). In conclusion, the quality improvement program was positively associated with the provision of prehospital ALS interventions and prehospital ROSC following OHCA. The fixed ambulance crews performed better in critical care provision and prehospital outcome, yet increased protocol adherence and targeted training could fill the underperformance of non-fixed crews efficaciously.

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.

An epidemiological assessment of choking-induced out-of-hospital cardiac arrest: A post hoc analysis of the SOS-KANTO 2012 study

OBJECTIVES

The aim of this study was to reveal the neurological outcomes of choking-induced out-of-hospital cardiac arrest (OHCA) and evaluate the presence of witnesses, cardiopulmonary resuscitation (CPR) performed by a witness (bystander-witnessed CPR), and the proportion of patients with favourable neurological outcomes by the time from CPR by emergency medical services (EMS) to the return of spontaneous circulation (ROSC) (CPR-ROSC time).

METHODS

We retrospectively analysed the SOS-KANTO 2012 database, which included data of 16,452 OHCAs in Japan. We selected choking-induced OHCA patients aged ≥ 20 years. We evaluated the neurological outcomes at 1 month with the Cerebral Performance Category (CPC). We defined favourable neurological outcomes (CPCs: 1-2) and present the outcomes with descriptive statistics.

RESULTS

Of 1,045 choking-induced OHCA patients, 18 (1.7%) had a favourable neurological outcome. Of 1,045 OHCAs, 757 (72.6%) were witnessed, and 375 (36.0%) underwent bystander-witnessed CPR. Of the 18 OHCAs with favourable outcomes, 17 (94.4%) were witnessed, and 11 (61.1%) underwent bystander-witnessed CPR. With a CPR-ROSC time of 0-5 minutes, the proportion of patients with favourable neurological outcomes was 29.7%, ranging from 0% to 6% in the following time groups.

CONCLUSIONS

The neurological outcome of choking-induced OHCA was poor. The neurological outcomes deteriorated rapidly from 5 minutes after the initiation of CPR by EMS. The presence of witnesses and bystander-witnessed CPR may be factors that contribute to improved outcomes, but the effects were not remarkable. As another approach to reduce deaths due to choking, citizen education for the prevention of choking may be effective.

Improved neurologically favorable survival after OHCA is associated with increased pre-hospital advanced airway management at the prefecture level in Japan

Out-of-hospital cardiac arrest (OHCA) has high incidence and mortality. The survival benefit of pre-hospital advanced airway management (AAM) for OHCA remains controversial. In Japan, pre-hospital AAM are performed for OHCA by emergency medical services (EMS), however the relationship between resuscitation outcomes and AAM at the prefecture level has not been evaluated. The purpose of this study was to describe the association between AAM and neurologically favorable survival (cerebral performance category (CPC) ≦2) at prefecture level. This was a retrospective, population-based study of adult OHCA patients (≧ 18) from January 1, 2014 to December 31, 2017 in Japan. We excluded patients with EMS witnessed arrests. We also only included patients that had care provided by an ELST with the ability to provided AAM and excluded cases that involved prehospital care delivered by a physician. We categorized OHCA into four quartiles (four group: G1-G4) based on frequency of pre-hospital AAM approach rate by prefecture, which is the smallest geographical classification unit, and evaluated the relationship between frequency of pre-hospital AAM approach rates and CPC ≦ 2 for each quartile. Multivariable logistic regression was used to assess effectiveness of AAM on neurologically favorable survival. Among 493,577 OHCA cases, 403,707 matched our inclusion criteria. The number of CPC ≦ 2 survivors increased from G1 to G4 (p for trend < 0.001). In the adjusted multivariable regression, higher frequency of pre-hospital AAM approach was associated with CPC ≦ 2 (p < 0.001). High prefecture frequency of pre-hospital AAM approach was associated with neurologically favorable survival (CPC ≦ 2) in OHCA.

Analysis of Emergency Medical Response Team Performance during the International Winter Championships in Emergency Medicine

Background and Objectives: Conducting advanced life support (ALS) according to the guidelines of the European Resuscitation Council (ERC) requires medical personnel to implement the appropriate emergency actions. In particular, these actions include chest compressions, airway management, artificial ventilation, defibrillation and the administering of medicines. An appropriate training system enables members of medical response teams (MRT) to acquire the essential knowledge and skills necessary to correctly conduct cardiopulmonary resuscitation (CPR). One way to improve the quality of interventions by MRT personnel is participation in emergency medicine championships. Materials and Methods: The research analysed assessment cards for tasks carried out during the International Winter Championships in Emergency Medicine in the years 2013–2020. The assessed tasks were prepared and led by European Resuscitation Council instructors of advanced life support. During ten-minute scenarios of simulated sudden cardiac arrest (SCA) in adults, the judges assessed the compliance of procedures with current ERC guidelines. This research analysed the performance of 309 teams from Poland made up of paramedics from medical response units from all over the country. Results: In most cases, the study showed significant differences in the percentage of correctly performed procedures between years. Most often, the highest percentage of correctly performed procedures was recorded in 2019 and 2020. The lowest percentage of correctly performed procedures was most often recorded in 2013. In subsequent years, the percentage of use of tracheal intubation decreased (from 54.76% to 31.25%) in favour of an increase in the use of supraglottic airway device SAD (from 35.71% to 59.38%). Conclusions: The research has shown that in subsequent years of the Championships, the quality of the majority of assessed procedures carried out by members of MRT gradually improved. The research authors also observed that in subsequent years, the percentage of intubations decreased in favour of SAD.

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).

Emotions in telephone calls to emergency medical services involving out-of-hospital cardiac arrest: A scoping review

Aims

The purpose of this scoping review was to identify and synthesise existing research evidence on emotions in the context of emergency phone calls to emergency medical services (EMS) involving out-of-hospital cardiac arrest (OHCA). The specific objectives were to identify studies that (1) described emotions during emergency OHCA calls; (2) specified an instrument or method for measuring/assessing emotions; and (3) examined the relationship between emotions and call outcomes or patient outcomes.

Methods/Data sources

Five databases were searched on 18 November 2021: Medline, Embase, PsycInfo, CINAHL, and the Cochrane Review Database. Included studies required the following three concepts to be addressed: emotions in the context of EMS calls that involved OHCA. Calls also needed to be made by a 'second-party' caller; and each study needed to address at least one of the three specific objectives, as outlined above.The review was conducted in accordance with the Joanna Briggs Institute guidelines for evidence synthesis for scoping reviews.

Results

Thirteen eligible studies were included for synthesis. All studies met Objective 1; six studies met Objective 2; and seven met Objective 3. One study reported patient fatality due to heightened emotions and ensuing ineffective communications between callers and call-takers.

Conclusion

The review highlights a significant gap in the evidence base of emotions in emergency OHCA-related calls, and the need for a more comprehensive and effective method in assessing and measuring emotions in this context. Relationships between emotions (their expressions and perceptions) and call outcomes (including patient outcomes) also need more rigorous investigation.

The impact of COVID-19 on emergency medical service-led out-of-hospital cardiac arrest resuscitation: a qualitative study

Background

Following the emergence of COVID-19, there have been local and national changes in the way emergency medical service (EMS) staff respond to and treat patients in out-of-hospital cardiac arrest (OHCA). The views of EMS staff on the impact of COVID-19 and management of OHCA have not previously been explored. This study aimed to explore the views of staff, with a specific focus on communication during resuscitation, resuscitation procedures and the perception of risk.

Methods

A qualitative phenomenological enquiry was conducted. A purposive sample of n = 20 participants of various clinical grades was selected from NHS EMS providers in the United Kingdom. Data were collected using semi-structured interviews, transcribed verbatim and inductive thematic analysis was applied.

Results

Three main themes emerged which varied according to clinical grade, location and guidelines.Decision making: Staff generally felt supported to make best-interest termination of resuscitation decisions. Staff made informed decisions to compromise on recommended levels of personal protective equipment (PPE), since it felt impractical in the pre-hospital context, to improve communication or to reduce delays to care.Service pressures: Availability of operational staff and in-hospital capacity were reduced. Staff felt pressure and disconnect from the continuous updates to clinical guidelines which resulted in organisational change fatigue.Moral injury: The emotional impacts of prolonged and frequent exposure to failed resuscitation attempts and patient death caused many staff to take time away from work to recover.

Conclusion

This qualitative study is the first known to explore staff views on the impacts of COVID-19 on OHCA resuscitation, which found positive outcomes but also negative impacts important to inform EMS systems. Staff felt that COVID-19 created delays to the delivery of resuscitation, which were multi-faceted. Staff developed new ways of working to overcome the barriers of impractical PPE. There was little impact on resuscitation procedures. Moving forwards, EMS should consider how to limit organisational change and better support the ongoing emotional impacts on staff.