Factors associated with an increased chance of survival among patients suffering from an out-of-hospital cardiac arrest in a national perspective in Sweden

Simultaneous prognostic score validation in patients with out-of-hospital cardiac arrest by a post-hoc analysis based on national multicenter registry

Using a nationwide multicenter prospective registry in Japan's data, we calculated prognostic and predictive scores, including the Out-of-Hospital Cardiac Arrest (OHCA); Cardiac Arrest Hospital Prognosis (CAHP); Nonshockable rhythm, Unwitnessed arrest, Long no-flow or Long low-flow period, blood PH < 7.2, Lactate > 7.0 mmol/L, End-stage chronic kidney disease on dialysis, Age ≥ 85 years, Still resuscitation, and Extracardiac cause (NULL-PLEASE); revised post-Cardiac Arrest Syndrome for Therapeutic hypothermia (rCAST); and MIRACLE2 scores, for adult patients with cardiac arrest. The MIRACLE2 score was validated with the modified MIRACLE2 score, which excludes information of pupillary reflexes. Each score was calculated only for the cases with no missing data for the variables used. These scores' accuracies were compared using neurological outcomes 30 days after out-of-hospital cardiac arrest (OOHCA). Patients with a cerebral performance category scale of 1 or 2 were designated as having favorable neurological outcomes. Each score's discrimination ability was evaluated by the receiver operating characteristic curve's area under the curve (AUC). To assess in detail in areas of high specificity and high sensitivity, which are areas of interest to clinicians, partial AUCs were also used. The analysis included 11,924 hospitalized adult patients. The AUCs of the OHCA, MIRACLE2, CAHP, rCAST, and NULL-PLEASE scores for favorable neurological outcomes were 0.713, 0.727, 0.785, 0.761, and 0.831, respectively. The CAHP and NULL-PLEASE scores were significantly more accurate than the rest. Accuracies did not differ significantly between the CAHP and NULL-PLEASE scores. The NULL-PLEASE score was significantly better at discriminating favorable neurological prognoses at 30 days in patients with OOHCA compared to other scoring systems.

Effects of pre-existing type 1 diabetes mellitus on survival outcome following out-of-hospital cardiac arrest: a registry-based observational study in Sweden

BACKGROUND

It has been estimated that 80% of cases of out-of-hospital cardiac arrest (OHCA) are due to cardiac causes. It is well-documented that diabetes is a risk factor for conditions associated with sudden cardiac arrest. Type 1 diabetes (T1D) displays a threefold to fivefold increased risk of cardiovascular disease and death compared with the general population.

OBJECTIVE

This study aims to assess the characteristics and survival outcomes of individuals with and without T1D who experienced an OHCA. Design: A registry-based nationwide observational study with two cohorts, patients with T1D and patients without T1D. Setting: All emergency medical services and hospitals in Sweden were included in the study.

PARTICIPANTS

Using the Swedish Cardiopulmonary Resuscitation Registry, we enrolled 54 568 cases of OHCA where cardiopulmonary resuscitation was attempted between 2010 and 2020. Among them, 448 patients with T1D were identified using International Classification of Diseases-code: E10.

METHODS

Survival analysis was performed using Kaplan-Meier and logistic regression. Multiple regression was adjusted for age, sex, cause of arrest, prevalence of T1D and time to cardiopulmonary resuscitation.

MAIN OUTCOME MEASURES

The outcomes were discharge status (alive vs dead), 30 days survival and neurological outcome at discharge.

RESULTS

There were no significant differences in patients discharged alive with T1D 37.3% versus, 46% among cases without T1D. There was also no difference in neurological outcome. Kaplan-Meier curves yielded no significant difference in long-term survival. Multiple regression showed no significant association with survival after accounting for covariates, OR 0.99 (95% CI 0.96 to 1.02), p value=0.7. Baseline characteristics indicate that patients with T1D were 5 years younger at OHCA occurrence and had proportionally fewer cases of heart disease as the cause of arrest (57.6% vs 62.7%).

CONCLUSION

We conclude, with the current sample size, that there is no statistically significant difference in long-term or short-term survival between patients with and without T1D following OHCA.

Rat model of asphyxia-induced cardiac arrest and resuscitation

Neurologic injury after cardiopulmonary resuscitation is the main cause of the low survival rate and poor quality of life among patients who have experienced cardiac arrest. In the United States, as the American Heart Association reported, emergency medical services respond to more than 347,000 adults and more than 7,000 children with out-of-hospital cardiac arrest each year. In-hospital cardiac arrest is estimated to occur in 9.7 per 1,000 adult cardiac arrests and 2.7 pediatric events per 1,000 hospitalizations. Yet the pathophysiological mechanisms of this injury remain unclear. Experimental animal models are valuable for exploring the etiologies and mechanisms of diseases and their interventions. In this review, we summarize how to establish a standardized rat model of asphyxia-induced cardiac arrest. There are four key focal areas: (1) selection of animal species; (2) factors to consider during modeling; (3) intervention management after return of spontaneous circulation; and (4) evaluation of neurologic function. The aim was to simplify a complex animal model, toward clarifying cardiac arrest pathophysiological processes. It also aimed to help standardize model establishment, toward facilitating experiment homogenization, convenient interexperimental comparisons, and translation of experimental results to clinical application.

Identification and Validation of Novel Potential Pathogenesis and Biomarkers to Predict the Neurological Outcome after Cardiac Arrest

Predicting neurological outcomes after cardiac arrest remains a major issue. This study aimed to identify novel biomarkers capable of predicting neurological prognosis after cardiac arrest. Expression profiles of GSE29540 and GSE92696 were downloaded from the Gene Expression Omnibus (GEO) database to obtain differentially expressed genes (DEGs) between high and low brain performance category (CPC) scoring subgroups. Weighted gene co-expression network analysis (WGCNA) was used to screen key gene modules and crossover genes in these datasets. The protein-protein interaction (PPI) network of crossover genes was constructed from the STRING database. Based on the PPI network, the most important hub genes were identified by the cytoHubba plugin of Cytoscape software. Eight hub genes (RPL27, EEF1B2, PFDN5, RBX1, PSMD14, HINT1, SNRPD2, and RPL26) were finally screened and validated, which were downregulated in the group with poor neurological prognosis. In addition, GSEA identified critical pathways associated with these genes. Finally, a Pearson correlation analysis showed that the mRNA expression of hub genes EEF1B2, PSMD14, RPFDN5, RBX1, and SNRPD2 were significantly and positively correlated with NDS scores in rats. Our work could provide comprehensive insights into understanding pathogenesis and potential new biomarkers for predicting neurological outcomes after cardiac arrest.

Continuous versus routine EEG in patients after cardiac arrest-Analysis of a randomized controlled trial (CERTA) - RESUS-D-22-00369

BACKGROUND

Electroencephalography (EEG) is essential to assess prognosis in patients after cardiac arrest (CA). Use of continuous EEG (cEEG) is increasing in critically-ill patients, but it is more resource-consuming than routine EEG (rEEG). Observational studies did not show a major impact of cEEG versus rEEG on outcome, but randomized studies are lacking.

METHODS

We analyzed data of the CERTA trial (NCT03129438), including comatose adults after CA undergoing cEEG (30-48 hours) or two rEEG (20-30 minutes each). We explored correlations between recording EEG type and mortality (primary outcome), or Cerebral Performance Categories (CPC, secondary outcome), assessed blindly at 6 months, using uni- and multivariable analyses (adjusting for other prognostic variables showing some imbalance across groups).

RESULTS

We analyzed 112 adults (52 underwent rEEG, 60 cEEG,); 31 (27.7%) were women; 68 (60.7%) patients died. In univariate analysis, mortality (rEEG 59%, cEEG 65%, p=0.318) and good outcome (CPC 1-2; rEEG 33%, cEEG 27%, p=0.247) were comparable across EEG groups. This did not change after multiple logistic regressions, adjusting for shockable rhythm, time to return of spontaneous circulation, serum neuron-specific enolase, EEG background reactivity, regarding mortality (rEEG vs cEEG: OR 1.60, 95% CI 0.43 - 5.83, p=0.477), and good outcome (OR 0.51, 95% CI 0.14 - 1.90, p=0.318).

CONCLUSION

This analysis suggests that cEEG or repeated rEEG are related to comparable outcomes of comatose patients after CA. Pending a prospective, large randomized trial, this finding does not support the routine use of cEEG for prognostication in this setting. Trial registration Continuous EEG Randomized Trial in Adults (CERTA); NCT03129438; July 25, 2019.

Early or late booster for basic life support skill for laypeople: a simulation-based randomized controlled trial

PURPOSE

Retention of skills and knowledge has been shown to be poor after resuscitation training. The effect of a "booster" is controversial and may depend on its timing. We compared the effectiveness of an early versus late booster session after Basic Life Support (BLS) training for skill retention at 4 months.

METHODS

We performed a single-blind randomized controlled trial in a simulation environment. Eligible participants were adult laypeople with no BLS training or practice in the 6 months prior to the study. We provided participants with formal BLS training followed by an immediate BLS skills post-test. We then randomized participants to one of three groups: control, early booster, or late booster. Based on their group allocation, participants attended a brief BLS refresher at either 3 weeks after training (early booster), at 2 months after training (late booster), or not at all (control). All participants underwent a BLS skills retention test at 4 months. We measured BLS skill performance according to the Heart and Stroke Foundation's skills testing checklist for adult CPR and the use of an automated external defibrillator.

RESULTS

A total of 80 laypeople were included in the analysis (control group, n = 28; early booster group, n = 23; late booster group, n = 29). The late booster group achieved better skill retention (mean difference in checklist score at retention compared to the immediate post-test = - 0.8 points out of 15, [95% CI - 1.7, 0.2], P = 0.10) compared to the early booster (- 1.3, [- 2.6, 0.0], P = 0.046) and control group (- 3.2, [- 4.7, - 1.8], P < 0.001).

CONCLUSION

A late booster session improves BLS skill retention at 4 months in laypeople.

TRIAL REGISTRATION NUMBER

NCT02998723.

Survival and Factors Associated with Survival with Extracorporeal Life Support During Cardiac Arrest: A Systematic Review and Meta-Analysis

The survival rate after cardiac arrest (CA) remains low. The utilization of extracorporeal life support is proposed to improve management. However, this resource-intensive tool is associated with complications and must be used in selected patients. We performed a meta-analysis to determine predictive factors of survival. Among the 81 studies included, involving 9256 patients, survival was 26.2% at discharge and 20.4% with a good neurologic outcome. Meta-regressions identified an association between survival at discharge and lower lactate values, intrahospital CA, and lower cardio pulmonary resuscitation (CPR) duration. After adjustment for age, intrahospital CA, and mean CPR duration, an initial shockable rhythm was the only remaining factor associated with survival to discharge (β = 0.02, 95% CI: 0.007-0.02; p = 0.0004).

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

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

The effect of content knowledge and repeated teaching on teaching and learning basic life support: a cluster randomised controlled trial

BACKGROUND

Experimental research on the training of BLS instructors and how their performance evolves is scarce. This study investigated the role of content knowledge and repeated teaching trials for improving teaching and learning Basic Life Support (BLS).

METHODS

A cluster randomised controlled trial. Six secondary school teachers were assigned to either a common content knowledge (CCK) or specialised content knowledge (SCK) training. In the CCK group, teachers were taught to perform BLS technically correct. In the SCK group, teachers were additionally taught to detect and correct common errors students would make. Following the training, teachers taught two BLS lessons to two different classes of secondary school students (n = 216, age 12-14). Teachers' lesson organisation in terms of cognitive (e.g. task presentations), motor (e.g. practice time), and general (e.g. getting organised) activities was assessed. Students' BLS and CPR performance was assessed as the primary outcomes.

RESULTS

BLS performance was significantly higher in the second lesson for students taught by SCK versus CCK teachers (73% vs 63%). No significant difference was detected between lesson one and two across conditions and teachers. For cardiopulmonary resuscitation (CPR) variables, significant differences in favour of the SCK condition were found for chest compression depth after lesson one, and the amount and volume of ventilations after lesson two.

CONCLUSION

Students' BLS and CPR performance was positively impacted by the SCK training. BLS performance varied greatly by teachers with averages ranging from 53% to 83% across conditions. Results suggest teaching experience alone is not sufficient to improve teaching effectiveness.

Simultaneous external validation of various cardiac arrest prognostic scores: a single-center retrospective study

Background

This study aimed to compare and validate the out-of-hospital cardiac arrest (OHCA); cardiac arrest hospital prognosis (CAHP); non-shockable rhythm, unwitnessed arrest, long no-flow or long low-flow period, blood pH < 7.2, lactate > 7.0 mmol/L, end-stage chronic kidney disease, age ≥ 85 years, still resuscitation, and extracardiac cause (NULL-PLEASE) clinical; post-cardiac arrest syndrome for therapeutic hypothermia (CAST); and revised CAST (rCAST) scores in OHCA patients treated with recent cardiopulmonary resuscitation strategies.

Methods

We retrospectively collected data on adult OHCA patients admitted to our emergency department between February 2015 and July 2018. OHCA, CAHP, NULL-PLEASE clinical, CAST, and rCAST scores were calculated based on the data collected. The predictive abilities of each score were tested using the area under the curve (AUC) of the receiver operating characteristic (ROC) curve.

Results

We identified 236 OHCA patients from computer-based medical records and analyzed 189 without missing data. In OHCA patients without bystander witnesses, CAHP and OHCA scores were not calculated. Although the predictive abilities of the scores were not significantly different, the NULL-PLEASE score had a large AUC of ROC curve in various OHCA patients. Furthermore, in patients with bystander-witnessed OHCA, the NULL-PLEASE score had large partial AUCs of ROC from sensitivity 0.8–1.0 and specificity 0.8–1.0.

Conclusions

The NULL-PLEASE score had a high, comprehensive predictive ability in various OHCA patients. Furthermore, the NULL-PLEASE score had a high predictive ability for good and poor neurological outcomes in patients with bystander-witnessed OHCA.

Interaction Effect Between Prehospital Mechanical Chest Compression Device Use and Post-Cardiac Arrest Care on Clinical Outcomes After Out-Of-Hospital Cardiac Arrest

BACKGROUND

Prehospital application of a mechanical chest compression device (MCD) and post-cardiac arrest (PCA) care including coronary reperfusion therapy (CRT) or targeted temperature management (TTM) could affect the clinical outcome in out-of-hospital cardiac arrest (OHCA).

OBJECTIVES

This study aimed to assess whether the effect of PCA care including CRT or TTM differs according to prehospital MCD use in patients with OHCA.

METHODS

Adult OHCA cases with a presumed cardiac etiology and with survival to admission from 2016 to 2017 were enrolled from the Korean nationwide OHCA registry. The main exposures were CRT and TTM during PCA care. The primary outcome was good neurologic recovery defined by a cerebral performance category score of 1 or 2 at hospital discharge. We conducted interaction analyses between MCD use and PCA care including CRT or TTM.

RESULTS

Four thousand three hundred sixty-six OHCA cases were enrolled and 7.9% underwent MCD application. TTM and CRT were performed in 11.2% and 17.9% of the study population. In the interaction analysis, the adjusted odds ratios of TTM and CRT for good neurologic recovery were 2.41 (1.90-3.06) and 3.40 (2.79-4.14) in patients without MCD use and 1.89 (0.97-3.68), and 1.54 (0.79-3.01) in patients with MCD use.

CONCLUSIONS

The effect of PCA care on neurologic outcomes was different according to MCD use in OHCA. The association of good neurologic outcome and PCA care was not observed in the prehospital MCD use group compared with that in the MCD nonuse group.

Cardiac arrest in older adult patients

PURPOSE OF REVIEW

To describe the epidemiology, prognostication, and treatment of out- and in-hospital cardiac arrest (OHCA and IHCA) in elderly patients.

RECENT FINDINGS

Elderly patients undergoing cardiac arrest (CA) challenge the appropriateness of attempting cardiopulmonary resuscitation (CPR). Current literature suggests that factors traditionally associated with survival to hospital discharge and neurologically intact survival after CA cardiac arrest in general (e.g. presenting ryhthm, bystander CPR, targeted temperature management) may not be similarly favorable in elderly patients. Alternative factors meaningful for outcome in this special population include prearrest functional status, comorbidity load, the specific age subset within the elderly population, and CA location (i.e., nursing versus private home). Age should therefore not be a standalone criterion for withholding CPR. Attempts to perform CPR in an elderly patient should instead stem from a shared decision-making process.

SUMMARY

An appropriate CPR attempt is an attempt resulting in neurologically intact survival. Appropriate CPR in elderly patients requires better risk classification. Future research should therefore focus on the associations of specific within-elderly age subgroups, comorbidities, and functional status with neurologically intact survival. Reporting must be standardized to enable such evaluation.

Comparison of Mortality Risk Models in Patients with Postcardiac Arrest Cardiogenic Shock and Percutaneous Mechanical Circulatory Support

Background

Although scoring systems are widely used to predict outcomes in postcardiac arrest cardiogenic shock (CS) after out-of-hospital cardiac arrest (OHCA) complicating acute myocardial infarction (AMI), data concerning the accuracy of these scores to predict mortality of patients treated with Impella in this setting are lacking. Thus, we aimed to evaluate as well as to compare the prognostic accuracy of acute physiology and chronic health II (APACHE II), simplified acute physiology score II (SAPS II), sepsis-related organ failure assessment (SOFA), the intra-aortic balloon pump (IABP), CardShock, the prediction of cardiogenic shock outcome for AMI patients salvaged by VA-ECMO (ENCOURAGE), and the survival after venoarterial extracorporeal membrane oxygenation (SAVE) score in patients with OHCA refractory CS due to an AMI treated with Impella 2.5 or CP.

Methods

Retrospective study of 65 consecutive Impella 2.5 and 32 CP patients treated in our cardiac arrest center from September 2015 until June 2020.

Results

Overall survival to discharge was 44.3%. The expected mortality according to scores was SOFA 70%, SAPS II 90%, IABP shock 55%, CardShock 80%, APACHE II 85%, ENCOURAGE 50%, and SAVE score 70% in the 2.5 group; SOFA 70%, SAPS II 85%, IABP shock 55%, CardShock 80%, APACHE II 85%, ENCOURAGE 75%, and SAVE score 70% in the CP group. The ENCOURAGE score was the most effective predictive model of mortality outcome presenting a moderate area under the curve (AUC) of 0.79, followed by the CardShock, APACHE II, IABP, and SAPS score. These derived an AUC between 0.71 and 0.78. The SOFA and the SAVE scores failed to predict the outcome in this particular setting of refractory CS after OHCA due to an AMI.

Conclusion

The available intensive care and newly developed CS scores offered only a moderate prognostic accuracy for outcomes in OHCA patients with refractory CS due to an AMI treated with Impella. A new score is needed in order to guide the therapy in these patients.

Evolution of Bystander Intention to Perform Resuscitation Since Last Training: Web-Based Survey

BACKGROUND

Victims of out-of-hospital cardiac arrest (OHCA) have higher survival rates and more favorable neurological outcomes when basic life support (BLS) maneuvers are initiated quickly after collapse. Although more than half of OHCAs are witnessed, BLS is infrequently provided, thereby worsening the survival and neurological prognoses of OHCA victims. According to the theory of planned behavior, the probability of executing an action is strongly linked to the intention of performing it. This intention is determined by three distinct dimensions: attitude, subjective normative beliefs, and control beliefs. We hypothesized that there could be a decrease in one or more of these dimensions even shortly after the last BLS training session.

OBJECTIVE

The aim of this study was to measure the variation of the three dimensions of the intention to perform resuscitation according to the time elapsed since the last first-aid course.

METHODS

Between January and April 2019, the two largest companies delivering first-aid courses in the region of Geneva, Switzerland sent invitation emails on our behalf to people who had followed a first-aid course between January 2014 and December 2018. Participants were asked to answer a set of 17 psychometric questions based on a 4-point Likert scale ("I don't agree," "I partially agree," "I agree," and "I totally agree") designed to assess the three dimensions of the intention to perform resuscitation. The primary outcome was the difference in each of these dimensions between participants who had followed a first-aid course less than 6 months before taking the questionnaire and those who took the questionnaire more than 6 months and up to 5 years after following such a course. Secondary outcomes were the change in each dimension using cutoffs at 1 year and 2 years, and the change regarding each individual question using cutoffs at 6 months, 1 year, and 2 years. Univariate and multivariable linear regression were used for analyses.

RESULTS

A total of 204 surveys (76%) were analyzed. After adjustment, control beliefs was the only dimension that was significantly lower in participants who took the questionnaire more than 6 months after their last BLS course (P<.001). Resisting diffusion of responsibility, a key element of subjective normative beliefs, was also less likely in this group (P=.001). By contrast, members of this group were less afraid of disease transmission (P=.03). However, fear of legal action was higher in this group (P=.02).

CONCLUSIONS

Control beliefs already show a significant decrease 6 months after the last first-aid course. Short interventions should be designed to restore this dimension to its immediate postcourse state. This could enhance the provision of BLS maneuvers in cases of OHCA.

[Advanced Resuscitation Measures: Extracorporeal Cardiopulmonary Resuscitation]

An extracorporeal cardiopulmonary resuscitation (eCPR) is considered as a therapy option for cardiovascular failure that is refractory to therapy. It can significantly improve the survival rate with favourable neurological results in highly selected patients. The initially defibrillatable heart rhythm and the short low-flow time < 60 minutes are of particular prognostic value. An essential prerequisite for deciding on eCPR is the existence of a reversible cause for cardiac arrest. Whether an eCPR directly at the emergency site (out-of-hospital variant) or in the clinic, e.g. in the cardiac catheterization laboratory (in-hospital variant) can be recommended must be clarified in further randomized-controlled, multicentre studies. Both variants have advantages and disadvantages. With the out-of-hospital eCPR, the "collapse-to-start-eCPR-time" can be significantly reduced under certain conditions. With the in-hospital eCPR external negative influences can be greatly minimized.

Successful Use of Early Therapeutic Hypothermia in an MDMA and Amphetamine Intoxication-Induced Out-of-Hospital Cardiac Arrest: A Case Report

BACKGROUND

Deaths caused by recreational drug abuse have increased considerably in recent years. Therapeutic hypothermia offers the potential to improve neurological outcomes in post-resuscitation patients.

CASE REPORT

A 19-year-old man was brought to our emergency department after suffering out-of-hospital ventricular fibrillation (VF) cardiac arrest. He was resuscitated at our emergency department again due to VF. Urine analysis showed high levels of amphetamine and 3,4 methylenedioxymethamphetamine (MDMA) (ecstasy). The patient was intubated, sedated, and ventilated. Within 1 h after the return of spontaneous circulation and hemodynamic stabilization, therapeutic hypothermia was initiated for neurologic protection. An external-cooling device was used for cooling. He was maintained at 33^oC for 72 h. The patient was weaned from the ventilator and extubated on day 5. He was discharged from the hospital on the day 10 with good cerebral performance. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Initiation of early therapeutic hypothermia within 1 h after return of spontaneous circulation might contribute to better neurologic outcome in patients who suffer VF cardiac arrest. We suggest that early therapeutic hypothermia may be considered in patients who suffer out-of-hospital cardiac arrest due to MDMA and amphetamine intoxications.

N-terminal pro-B-type natriuretic peptide as a prognostic indicator for 30-day mortality following out-of-hospital cardiac arrest: a prospective observational study

BACKGROUND

Early risk stratification applying cardiac biomarkers may prove useful in sudden cardiac arrest patients. We investigated the prognostic utility of early-on levels of high sensitivity cardiac troponin-T (hs-cTnT), copeptin and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with out-of-hospital cardiac arrest (OHCA).

METHODS

We conducted a prospective observational unicenter study, including patients with OHCA of assumed cardiac origin from the southwestern part of Norway from 2007 until 2010. Blood samples for later measurements were drawn during cardiopulmonary resuscitation or at hospital admission.

RESULTS

A total of 114 patients were included, 37 patients with asystole and 77 patients with VF as first recorded heart rhythm. Forty-four patients (38.6%) survived 30-day follow-up. Neither hs-cTnT (p = 0.49), nor copeptin (p = 0.39) differed between non-survivors and survivors, whereas NT-proBNP was higher in non-survivors (p <  0.001) and significantly associated with 30-days all-cause mortality in univariate analysis, with a hazard ratio (HR) for patients in the highest compared to the lowest quartile of 4.6 (95% confidence interval (CI), 2.1-10.1), p <  0.001. This association was no longer significant in multivariable analysis applying continuous values, [HR 0.96, (95% CI, 0.64-1.43), p = 0.84]. Similar results were obtained by dividing the population by survival at hospital admission, excluding non-return of spontaneous circulation (ROSC) patients on scene [HR 0.93 (95% CI, 0.50-1.73), P = 0.83]. We also noted that NT-proBNP was significantly higher in asystole- as compared to VF-patients, p <  0.001.

CONCLUSIONS

Early-on levels of hs-cTnT, copeptin and NT-proBNP did not provide independent prognostic information following OHCA. Prediction was unaffected by excluding on-scene non-ROSC patients in the multivariable analysis.

TRIAL REGISTRATION

ClinicalTrials. gov, NCT02886273 .

Artificial neural networks improve early outcome prediction and risk classification in out-of-hospital cardiac arrest patients admitted to intensive care

Background

Pre-hospital circumstances, cardiac arrest characteristics, comorbidities and clinical status on admission are strongly associated with outcome after out-of-hospital cardiac arrest (OHCA). Early prediction of outcome may inform prognosis, tailor therapy and help in interpreting the intervention effect in heterogenous clinical trials. This study aimed to create a model for early prediction of outcome by artificial neural networks (ANN) and use this model to investigate intervention effects on classes of illness severity in cardiac arrest patients treated with targeted temperature management (TTM).

Methods

Using the cohort of the TTM trial, we performed a post hoc analysis of 932 unconscious patients from 36 centres with OHCA of a presumed cardiac cause. The patient outcome was the functional outcome, including survival at 180 days follow-up using a dichotomised Cerebral Performance Category (CPC) scale with good functional outcome defined as CPC 1–2 and poor functional outcome defined as CPC 3–5. Outcome prediction and severity class assignment were performed using a supervised machine learning model based on ANN.

Results

The outcome was predicted with an area under the receiver operating characteristic curve (AUC) of 0.891 using 54 clinical variables available on admission to hospital, categorised as background, pre-hospital and admission data. Corresponding models using background, pre-hospital or admission variables separately had inferior prediction performance. When comparing the ANN model with a logistic regression-based model on the same cohort, the ANN model performed significantly better (p = 0.029). A simplified ANN model showed promising performance with an AUC above 0.852 when using three variables only: age, time to ROSC and first monitored rhythm. The ANN-stratified analyses showed similar intervention effect of TTM to 33 °C or 36 °C in predefined classes with different risk of a poor outcome.

Conclusion

A supervised machine learning model using ANN predicted neurological recovery, including survival excellently, and outperformed a conventional model based on logistic regression. Among the data available at the time of hospitalisation, factors related to the pre-hospital setting carried most information. ANN may be used to stratify a heterogenous trial population in risk classes and help determine intervention effects across subgroups.

Identifying the relative importance of predictors of survival in out of hospital cardiac arrest: a machine learning study

Introduction

Studies examining the factors linked to survival after out of hospital cardiac arrest (OHCA) have either aimed to describe the characteristics and outcomes of OHCA in different parts of the world, or focused on certain factors and whether they were associated with survival. Unfortunately, this approach does not measure how strong each factor is in predicting survival after OHCA.

Aim

To investigate the relative importance of 16 well-recognized factors in OHCA at the time point of ambulance arrival, and before any interventions or medications were given, by using a machine learning approach that implies building models directly from the data, and arranging those factors in order of importance in predicting survival.

Methods

Using a data-driven approach with a machine learning algorithm, we studied the relative importance of 16 factors assessed during the pre-hospital phase of OHCA. We examined 45,000 cases of OHCA between 2008 and 2016.

Results

Overall, the top five factors to predict survival in order of importance were: initial rhythm, age, early Cardiopulmonary Resuscitation (CPR, time to CPR and CPR before arrival of EMS), time from EMS dispatch until EMS arrival, and place of cardiac arrest. The largest difference in importance was noted between initial rhythm and the remaining predictors. A number of factors, including time of arrest and sex were of little importance.

Conclusion

Using machine learning, we confirm that the most important predictor of survival in OHCA is initial rhythm, followed by age, time to start of CPR, EMS response time and place of OHCA. Several factors traditionally viewed as important, e.g. sex, were of little importance.

Handling of Ventricular Fibrillation in the Emergency Setting

Ventricular fibrillation (VF) and sudden cardiac death (SCD) are predominantly caused by channelopathies and cardiomyopathies in youngsters and coronary heart disease in the elderly. Temporary factors, e.g., electrolyte imbalance, drug interactions, and substance abuses may play an additive role in arrhythmogenesis. Ectopic automaticity, triggered activity, and reentry mechanisms are known as important electrophysiological substrates for VF determining the antiarrhythmic therapies at the same time. Emergency need for electrical cardioversion is supported by the fact that every minute without defibrillation decreases survival rates by approximately 7%–10%. Thus, early defibrillation is an essential part of antiarrhythmic emergency management. Drug therapy has its relevance rather in the prevention of sudden cardiac death, where early recognition and treatment of the underlying disease has significant importance. Cardioprotective and antiarrhythmic effects of beta blockers in patients predisposed to sudden cardiac death were highlighted in numerous studies, hence nowadays these drugs are considered to be the cornerstones of the prevention and treatment of life-threatening ventricular arrhythmias. Nevertheless, other medical therapies have not been proven to be useful in the prevention of VF. Although amiodarone has shown positive results occasionally, this was not demonstrated to be consistent. Furthermore, the potential proarrhythmic effects of drugs may also limit their applicability. Based on these unfavorable observations we highlight the importance of arrhythmia prevention, where echocardiography, electrocardiography and laboratory testing play a significant role even in the emergency setting. In the following we provide a summary on the latest developments on cardiopulmonary resuscitation, and the evaluation and preventive treatment possibilities of patients with increased susceptibility to VF and SCD.

Lone and lonely in a double ambivalence situation as experienced by callers while waiting for the ambulance in a rural environment

BACKGROUND

In a rural environment where distances and access to ambulance resources in people's immediate area are limited, other responders like firefighters dispatched to perform a first aid before ambulance arrives in areas where a longer response time exists; an assignment called 'While Waiting for the Ambulance' (WWFA). Knowledge is limited about the experience from a caller's perspective when a person has a life-threatening condition needing emergency help and both firefighters in a WWFA assignment and ambulance staff are involved.

AIM

The aim of the study is to describe the emergency situation involving a WWFA assignment in a rural environment from the caller's perspective.

METHOD

A descriptive design using qualitative methodology with a reflective lifeworld research (RLR) approach was used for this study, including in-depth interviews with eight callers.

RESULTS

An emergency situation involving WWFA assignment in a rural environment mean a sense of being lone and lonely with a vulnerability in while waiting to hand over responsibility for the affected person. Ambivalence in several dimensions arises with simultaneous and conflicting emotions. A tension between powerlessness and power of action where the throw between doubt and hope are abrupt with a simultaneous pendulum between being in a chaos and in a calm.

CONCLUSION

A double ambivalence emerges between, on one hand feeling alone in the situation and having full control, on the other hand, with trust handing over the responsibility, thereby losing control. Contact with the emergency medical dispatcher becomes a saving lifeline to hold onto, and access to emergency help in the immediate area of WWFA is valuable and important. Trust and confidence are experienced when callers are met with empathy, regardless of personal acquaintance with arriving responders.

A systematic literature review and meta-analysis of the effectiveness of extracorporeal-CPR versus conventional-CPR for adult patients in cardiac arrest

Introduction

The probability of surviving a cardiac arrest remains low. International resuscitation guidelines state that extracorporeal cardiopulmonary resuscitation (ECPR) may have a role in selected patients suffering refractory cardiac arrest. Identifying these patients is challenging. This project systematically reviewed the evidence comparing the outcomes of ECPR over conventional-CPR (CCPR), before examining resuscitation-specific parameters to assess which patients might benefit from ECPR.

Method

Literature searches of studies comparing ECPR to CCPR and the clinical parameters of survivors of ECPR were performed. The primary outcome examined was survival at hospital discharge or 30 days. A secondary analysis examined the resuscitation parameters that may be associated with survival in patients who receive ECPR (no-flow and low-flow intervals, bystander-CPR, initial shockable cardiac rhythm, and witnessed cardiac arrest).

Results

Seventeen of 948 examined studies were included. ECPR demonstrated improved survival (OR 0.40 (0.27-0.60)) and a better neurological outcome (OR 0.10 (0.04-0.27)) over CCPR during literature review and meta-analysis. Characteristics that were associated with improved survival in patients receiving ECPR included an initial shockable rhythm and a shorter low-flow time. Shorter no-flow, the presence of bystander-CPR and witnessed arrests were not characteristics that were associated with improved survival following meta-analysis, although the quality of input data was low. All data were non-randomised, and hence the potential for bias is high.

Conclusion

ECPR is a sophisticated treatment option which may improve outcomes in a selected patient population in refractory cardiac arrest. Further comparative research is needed clarify the role of this potential resuscitative therapy.

Cardiovascular risk factors differently affect the survival of patients undergoing manual or mechanical resuscitation

Background

Chest compression is a decisive element of cardio-pulmonary resuscitation (CPR). By applying a mechanical CPR device, compression interruptions can be minimised. We examined the efficiency of manual and device-assisted resuscitation as well as the effects of cardiovascular risk factors on the outcome of resuscitation.

Methods

In our retrospective, randomised 3-year study the data of adult patients suffering non-traumatic, out-of-hospital, sudden cardiac death (SCD) were analysed (n = 287). The data were retrieved by processing case reports, Utstein sheets and acute coronary syndrome sheets. We compared the data of patients undergoing manual (n = 232) and device-assisted resuscitation (LUCAS-2, n = 55). The primary endpoint was the on-site restoration of spontaneous circulation (ROSC).

Results and conclusion

In 37% of the cases ROSC happened. With respect to ROSC an insignificantly more favourable tendency was demonstrated in the case of device-assisted resuscitation (p = 0.072). In the Lucas group, a higher success rate occurred even in the case of prolonged resuscitation. We found a better outcome in the Lucas group in the case of CPR started a longer time after the SCD (p < 0.05). A positive correlation was established between age and unsuccessful resuscitation (p = < 0.017; r = 0.125). An unfavourable correlation was observed between hypertension and the outcome of resuscitation (p = 0.018; r = 0.143). According to our results the presence of left ventricular hypertrophy poses 5.1-fold risk of unsuccessful CPR (CI: 4.97–5.29).

Advanced age and structural heart diseases can play a role in the genesis of SCD. Importantly, left ventricular hypertrophy and hypertension negatively affect survival.

Development of an online, universal, Utstein registry-based, care practice report card to improve out-of-hospital resuscitation practices

RATIONALE, AIMS AND OBJECTIVES

Care quality is a primary concern in health field. In France, the care practice report card (CPRC) is compulsory for practitioners. It is the first step towards the culture of excellence. In this context, practitioners have to assess and improve their practices. Competent authorities define registries as reliable sources for CPRC. The first aim of this work is to describe how we designed and built a universally transposable CPRC model based on an Utstein-style cardiac arrest registry. The second aim is to measure the adherence of practitioners to this approach and to show how such a tool can be used in real situation.

METHODS

Our report card is adapted from in-hospital CA care quality and safety indicators. We built a 2-section grid. The first part described the quality and completeness of the analysed data. The second part distinguished medical and traumatic CA and assesses care practices. We analysed the practitioners' adherence thanks to a satisfaction survey. Finally, we presented a CPRC case study.

RESULTS

This tool was tested in 92 centres gathering 8433 patients. The satisfaction survey showed that this CPRC was well accepted by emergency professionals. We presented an implementation example of this tool in a centre in real-life situation.

CONCLUSIONS

We designed and implemented a fully automated CPRC tool routinely usable for Utstein-style CA registries. This CPRC is easily transferable in all other Utstein CA registries. The debriefing report source codes are freely distributed upon request. This tool enables the care assessment and improvement.

Knowledge and attitudes of Singapore schoolchildren learning cardiopulmonary resuscitation and automated external defibrillator skills

INTRODUCTION

Victims of out-of-hospital cardiac arrests require timely cardiopulmonary resuscitation (CPR) and early defibrillation. Callers to emergency medical services are asked to provide dispatcher-guided responses until an ambulance arrives. Knowing what to expect in such circumstances should reduce both delay and confusion.

METHODS

This study was conducted among schoolchildren aged 11-17 years using ten-item pre- and post-training surveys. We aimed to observe any knowledge and attitude shifts regarding CPR and automated external defibrillator (AED) use subsequent to the training.

RESULTS

A total of 1,196 students across five schools completed the pre- and post-training surveys. Survey questions tested basic CPR knowledge and attitudes towards CPR and AED use. The overall response rate was 80.8% and 81.5% in the pre- and post-training surveys, respectively. There was a statistically significant improvement in the students' CPR knowledge. The number of students who selected all the correct answers for the knowledge-based questions in the post-training survey increased by 64.7% (95% confidence interval 61.9%-67.5%; p < 0.001). There was also an improvement in their willingness to administer CPR (likely/very likely to administer CPR pre-training vs. post-training: 13.0% vs. 71.0%; p < 0.001) and use AED (likely/very likely to administer AED pre-training vs. post-training: 11.7% vs. 78.0%; p < 0.001) after training.

CONCLUSION

The training programme imparted new information and skills, and improved attitudes towards providing CPR and using AED. However, some concerns persisted about hurting the victim while performing CPR.

Dispatcher-Assisted Telephone Cardiopulmonary Resuscitation Using a French-Language Compression-Ventilation Pediatric Protocol

OBJECTIVE

Out-of-hospital cardiac arrest (OHCA) in pediatrics is a devastating event associated with poor survival rates. Although telephone dispatcher-assisted cardiopulmonary resuscitation (CPR; T-CPR) instructions improve the frequency and quality of bystander CPR for OHCA in adults, this support remains undeveloped in children. Our objective was to assess the effectiveness of a pediatric T-CPR protocol in untrained and trained bystanders. Secondarily, we sought to determine the feasibility and the effectiveness of ventilation in such a protocol.

METHODS

Eligible adults with no CPR experience were recruited in a movie theater in Liege, as well as bachelor nursing students in Liege. All volunteers were randomly assigned either to T-CPR or to no-T-CPR using randomization. The volunteers were exposed to a pediatric manikin model cardiac arrest. On the basis of Cardiff evaluation test, data were collected to evaluate CPR performance.

RESULTS

A total of 115 volunteers were assigned to 4 groups: untrained nonguided group (n = 27), untrained guided group (n = 32), trained nonguided group (n = 26), and trained guided group (n = 30). We found an improvement in CPR performance in the guided groups. Most volunteers (81.2%) in untrained guided group and 83.3% in the trained guided group were able to give 2 ventilations after each compressions cycle.

CONCLUSIONS

In a pediatric manikin model of OHCA, T-CPR instructions including mouth-to-mouth ventilations and chest compressions produced a significant increase in resuscitation performance not only among previously untrained but also among trained volunteers.

Antiarrhythmic Drugs for Nonshockable-Turned-Shockable Out-of-Hospital Cardiac Arrest: The ALPS Study (Amiodarone, Lidocaine, or Placebo)

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) commonly presents with nonshockable rhythms (asystole and pulseless electric activity). It is unknown whether antiarrhythmic drugs are safe and effective when nonshockable rhythms evolve to shockable rhythms (ventricular fibrillation/pulseless ventricular tachycardia [VF/VT]) during resuscitation.

METHODS

Adults with nontraumatic OHCA, vascular access, and VF/VT anytime after ≥1 shock(s) were prospectively randomized, double-blind, to receive amiodarone, lidocaine, or placebo by paramedics. Patients presenting with initial shock-refractory VF/VT were previously reported. The current study was a prespecified analysis in a separate cohort that initially presented with nonshockable OHCA and was randomized on subsequently developing shock-refractory VF/VT. The primary outcome was survival to hospital discharge. Secondary outcomes included discharge functional status and adverse drug-related effects.

RESULTS

Of 37 889 patients with OHCA, 3026 with initial VF/VT and 1063 with initial nonshockable-turned-shockable rhythms were treatment-eligible, were randomized, and received their assigned drug. Baseline characteristics among patients with nonshockable-turned-shockable rhythms were balanced across treatment arms, except that recipients of a placebo included fewer men and were less likely to receive bystander cardiopulmonary resuscitation. Active-drug recipients in this cohort required fewer shocks, supplemental doses of their assigned drug, and ancillary antiarrhythmic drugs than recipients of a placebo (P<0.05). In all, 16 (4.1%) amiodarone, 11 (3.1%) lidocaine, and 6 (1.9%) placebo-treated patients survived to hospital discharge (P=0.24). No significant interaction between treatment assignment and discharge survival occurred with the initiating OHCA rhythm (asystole, pulseless electric activity, or VF/VT). Survival in each of these categories was consistently higher with active drugs, although the trends were not statistically significant. Adjusted absolute differences (95% confidence interval) in survival from nonshockable-turned-shockable arrhythmias with amiodarone versus placebo were 2.3% (-0.3, 4.8), P=0.08, and for lidocaine versus placebo 1.2% (-1.1, 3.6), P=0.30. More than 50% of these survivors were functionally independent or required minimal assistance. Drug-related adverse effects were infrequent.

CONCLUSIONS

Outcome from nonshockable-turned-shockable OHCA is poor but not invariably fatal. Although not statistically significant, point estimates for survival were greater after amiodarone or lidocaine than placebo, without increased risk of adverse effects or disability and consistent with previously observed favorable trends from treatment of initial shock-refractory VF/VT with these drugs. Together the findings may signal a clinical benefit that invites further investigation.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01401647.

Identification of novel biomarkers for prediction of neurological prognosis following cardiac arrest

Background

Early prognostication of neurological outcome in comatose patients after cardiac arrest (CA) is important for devising patient treatment strategies. However, there is still a lack of sensitive and specific biomarkers for easy identification of these patients. We evaluated whether molecular signatures from blood of CA patients might help to improve the prediction of neurological outcome.

Methods

We examined 22 comatose patients resuscitated after CA and obtained peripheral blood samples 48 hours after CA. To identify novel blood biomarkers, we aimed to measure neurological outcomes according to the Cerebral Performance Category (CPC) score at 6 months after CA and to determine blood transcriptome-based molecular signature of poor neurological outcome group.

Results

According to the CPC score, 10 patients exhibited a CPC score of one and 12 patients, a CPC score four to five. Blood transcriptomics revealed differently expressed profiles between the good outcome group and poor outcome group. A total of 150 genes were down-regulated and 237 genes were up-regulated in the poor neurological outcome group compared with good outcome group. From the blood transcriptome-based signatures, we identified that MAPK3, BCL2 and AKT1 were more specific and sensitive diagnostic biomarkers in poor neurological outcome with an area under the curve of 0.867 (p<0.0001), 0.800 (p=0.003), and 0.767 (p=0.016) respectively.

Conclusions

We identify three biomarkers as potential predictors of neurological outcome following CA. Further assessment of the prognostic value of transcriptomic analysis in larger cohorts of CA patients is needed.

Senior citizens as rescuers: Is reduced knowledge the reason for omitted lay-resuscitation-attempts? Results from a representative survey with 2004 interviews

Objective

Resuscitation (CPR) provided by a bystander prior to the arrival of the emergency services is a beneficial factor for surviving a cardiac arrest (CA). Our registry-based data show, that older patients receive bystander-CPR less frequently. Little is known on possible reasons for this finding. We sought to investigate the hypothesis that awareness of CPR measures is lower in older laypersons being a possible reason for less CPR-attempts in senior citizens.

Methods

1206 datasets on bystander resuscitations actually carried out were analyzed for age-dependent differences. Subsequently, we investigated whether the knowledge required carrying out bystander-CPR and the self-confidence to do so differ between younger and older citizens using computer-assisted telephone interviewing. 2004 interviews were performed and statistically analyzed.

Results

A lower level of knowledge to carry out bystander-CPR was seen in older individuals. For example, 82.4% of interviewees under 65 years of age, knew the correct emergency number. In this group, 66.6% named CPR as the relevant procedure in CA. Among older individuals these responses were only given by 75.1% and 49.5% (V = 0.082; P < 0.001 and V = 0.0157; P < 0.001). Additionally, a difference concerning participants’ confidence in their own abilities was detectable. 58.0% of the persons younger than 65 years were confident that they would detect a CA in comparison to 44.6% of the participants older than 65 years (V = 0.120; P < 0.001). Similarly, 62.7% of the interviewees younger than 65 were certain to know what to do during CPR compared to 51.3% of the other group (V = 0.103; P < 0.001).

Conclusions

Lower levels of older bystanders' knowledge and self-confidence might provide an explanation for why older patients receive bystander-CPR less frequently. Further investigation is necessary to identify causal connections and optimum ways to empower bystander resuscitation.

Early predictors of poor outcome after out-of-hospital cardiac arrest

Background

Early identification of predictors for a poor long-term outcome in patients who survive the initial phase of out-of-hospital cardiac arrest (OHCA) may facilitate future clinical research, the process of care and information provided to relatives. The aim of this study was to determine the association between variables available from the patient’s history and status at intensive care admission with outcome in unconscious survivors of OHCA.

Methods

Using the cohort of the Target Temperature Management trial, we performed a post hoc analysis of 933 unconscious patients with OHCA of presumed cardiac cause who had a complete 6-month follow-up. Outcomes were survival and neurological function as defined by the Cerebral Performance Category (CPC) scale at 6 months after OHCA. After multiple imputations to compensate for missing data, backward stepwise multivariable logistic regression was applied to identify factors independently predictive of a poor outcome (CPC 3–5). On the basis of these factors, a risk score for poor outcome was constructed.

Results

We identified ten independent predictors of a poor outcome: older age, cardiac arrest occurring at home, initial rhythm other than ventricular fibrillation/tachycardia, longer duration of no flow, longer duration of low flow, administration of adrenaline, bilateral absence of corneal and pupillary reflexes, Glasgow Coma Scale motor response 1, lower pH and a partial pressure of carbon dioxide in arterial blood value lower than 4.5 kPa at hospital admission. A risk score based on the impact of each of these variables in the model yielded a median (range) AUC of 0.842 (0.840–0.845) and good calibration. Internal validation of the score using bootstrapping yielded a median (range) AUC corrected for optimism of 0.818 (0.816–0.821).

Conclusions

Among variables available at admission to intensive care, we identified ten independent predictors of a poor outcome at 6 months for initial survivors of OHCA. They reflected pre-hospital circumstances (six variables) and patient status on hospital admission (four variables). By using a simple and easy-to-use risk scoring system based on these variables, patients at high risk for a poor outcome after OHCA may be identified early.

Features of hospital and emergency medical service in out-of-hospital cardiac arrest patients with shockable rhythm

OBJECTIVE

Predicting the outcome of out-of-hospital cardiac arrest (OHCA) patients is crucial. We examined hospital characteristics and parameters of emergency medical service (including scene time interval and direct ambulance delivery to intensive heart hospitals) as survival or outcome predictors.

STUDY DESIGN

Data from 546 consecutive OHCA shockable patients treated between January 2012 and December 2015 in Taoyuan City (Taiwan, ROC) were collected. In addition to demographic data, location of arrest, initial rhythm, availability of a hospital with or without 24/7 percutaneous coronary intervention (PCI), emergency medical service (EMS) time, provision of cardiopulmonary resuscitation by a bystander, presence of a witness at collapse, and level of life support were analysed.

RESULTS

Multivariate analysis showed that hospitalisation with immediate PCI availability was an independent predictor (OR: 4.32; 95% CI: 1.27-14.70) solely for the outcome of survival until discharge. The presence of a witness while collapsing (OR: 3.52; 95% CI: 1.03-11.98), EMS response time (OR: 0.83; 95% CI: 0.70-0.98), and scene time interval (STI; OR: 0.89; 95% CI: 0.81-0.99) were valuable for predicting the neurological outcome.

CONCLUSIONS

Direct ambulance delivery to intensive heart hospitals that had 24/7 PCI availability was associated with a higher probability of surviving until discharge in OHCA patients with shockable rhythms. Similarly, a witnessed collapse was correlated with being discharged alive from hospital and recovering with good cerebral performance. In addition, longer response time and scene time interval indicated poorer survival and neurological outcome.

Extracorporeal membrane oxygenation for refractory cardiac arrest

Extracorporeal cardiopulmonary resuscitation (ECPR) is the use of rapid deployment venoarterial (VA) extracorporeal membrane oxygenation to support systemic circulation and vital organ perfusion in patients in refractory cardiac arrest not responding to conventional cardiopulmonary resuscitation (CPR). Although prospective controlled studies are lacking, observational studies suggest improved outcomes compared with conventional CPR when ECPR is instituted within 30–60 min following cardiac arrest. Adult and pediatric patients with witnessed in-hospital and out-of-hospital cardiac arrest and good quality CPR, failure of at least 15 min of conventional resuscitation, and a potentially reversible cause for arrest are candidates. Percutaneous cannulation where feasible is rapid and can be performed by nonsurgeons (emergency physicians, intensivists, cardiologists, and interventional radiologists). Modern extracorporeal systems are easy to prime and manage and are technically easy to manage with proper training and experience. ECPR can be deployed in the emergency department for out-of-hospital arrest or in various inpatient units for in-hospital arrest. ECPR should be considered for patients with refractory cardiac arrest in hospitals with an existing extracorporeal life support program, able to provide rapid deployment of support, and with resources to provide postresuscitation evaluation and management.

Implementing Cardiopulmonary Resuscitation Training Programs in High Schools: Iowa's Experience

OBJECTIVE

To understand perceived barriers to providing cardiopulmonary resuscitation (CPR) education, implementation processes, and practices in high schools.

STUDY DESIGN

Iowa has required CPR as a graduation requirement since 2011 as an unfunded mandate. A cross-sectional study was performed through multiple choice surveys sent to Iowa high schools to collect data about school demographics, details of CPR programs, cost, logistics, and barriers to implementation, as well as automated external defibrillator training and availability.

RESULTS

Eighty-four schools responded (26%), with the most frequently reported school size of 100-500 students and faculty size of 25-50. When the law took effect, 51% of schools had training programs already in place; at the time of the study, 96% had successfully implemented CPR training. Perceived barriers to implementation were staffing, time commitment, equipment availability, and cost. The average estimated startup cost was <$1000 US, and the yearly maintenance cost was <$500 with funds typically allocated from existing school resources. The facilitator was a school official or volunteer for 81% of schools. Average estimated training time commitment per student was <2 hours. Automated external defibrillators are available in 98% of schools, and 61% include automated external defibrillator training in their curriculum.

CONCLUSIONS

Despite perceived barriers, school CPR training programs can be implemented with reasonable resource and time allocations.

Retention of Basic Life Support in Laypeople: Mastery Learning vs. Time-based Education

OBJECTIVE

To compare the effectiveness of a mastery learning (ML) versus a time-based (TB) BLS course for the acquisition and retention of BLS knowledge and skills in laypeople.

METHODS

After ethics approval, laypeople were randomized to a ML or TB BLS course based on the American Heart Association (AHA) Heartsaver course. In the ML group, subjects practiced and received feedback at six BLS stations until they reached a pre-determined level of performance. The TB group received a standard AHA six-station BLS course. All participants took the standard in-course BLS skills test at the end of their course. BLS skills and knowledge were tested using a high-fidelity scenario and knowledge questionnaire upon course completion (immediate post-test) and after four months (retention test). Video recorded scenarios were assessed by two blinded, independent raters using the AHA skills checklist.

RESULTS

Forty-three subjects were included in analysis (23ML;20TB). For primary outcome, subjects' performance did not change after four months, regardless of the teaching modality (TB from (median[IQR]) 8.0[6.125;8.375] to 8.5[5.625;9.0] vs. ML from 8.0[7.0;9.0] to 7.0[6.0;8.0], p = 0.12 for test phase, p = 0.21 for interaction between effect of teaching modality and test phase). For secondary outcomes, subjects acquired knowledge between pre- and immediate post-tests (p < 0.005), and partially retained the acquired knowledge up to four months (p < 0.005) despite a decrease between immediate post-test and retention test (p = 0.009), irrespectively of the group (p = 0.59) (TB from 63.3[48.3;73.3] to 93.3[81.7;100.0] and then 93.3[81.7;93.3] vs. ML from 60.0[46.7;66.7] to 93.3[80.0;100.0] and then 80.0[73.3;93.3]). Regardless of the group after 4 months, chest compression depth improved (TB from 39.0[35.0;46.0] to 48.5[40.25;58.0] vs. ML from 40.0[37.0;47.0] to 45.0[37.0;52.0]; p = 0.012), but not the rate (TB from 118.0[114.0;125.0] to 120.5[113.0;129.5] vs. ML from 119.0[113.0;130.0] to 123.0[102.0;132.0]; p = 0.70). All subjects passed the in-course BLS skills test. Pass/fail rates were poor in both groups at both the simulated immediate post-test (ML = 1/22;TB = 0/20; p = 0.35) and retention test (ML pass/fail = 1/22, TB pass/fail = 0/20; p = 0.35). The ML course was slightly longer than the TB course (108[94;117] min vs. 95[89;102] min; p = 0.003).

CONCLUSIONS

There was no major benefit of a ML compared to a TB BLS course for the acquisition and four-month retention of knowledge or skills among laypeople.

Epidemiology of traumatic cardiac arrest in patients presenting to emergency department at a level 1 trauma center

Introduction:

There is a paucity of literature on prehospital care and epidemiology of traumatic cardiac arrest (TCA) in India. This study highlights the profile and characteristics of TCA.

Methods:

A retrospective cohort study was conducted to study epidemiological profile of TCA patients ≥1 year presenting to a level 1 trauma center of India.

Results:

One thousand sixty-one patients were recruited in the study. The median age (interquartile range) was 32 (23–45) years (male:female ratio of 5.9:1). Asystole (253), pulseless electrical activity (11), ventricular fibrillation (six), and ventricular tachycardia (five) were initial arrest rhythm. Road traffic crash (RTC) (57.16%), fall from height (18.52%), and assault (10.51%) were modes of injury. Prehospital care was provided by police (36.59%), ambulance (10.54%), relatives (45.40%), and bystanders (7.47% cases). Return of spontaneous circulation was seen in 69 patients, of which only three survived to hospital discharge.

Conclusion:

RTC in young males was a major cause of TCA. Asystole was the most common arrest rhythm. Police personnel were major prehospital service provider. Prehospital care needs improvement including the development of robust TCA registry.

Layperson mouth-to-mask ventilation using a modified I-gel laryngeal mask after brief onsite instruction: a manikin-based feasibility trial

OBJECTIVE

The intention of this manikin-based trial was to evaluate whether laypersons are able to operate an I-gel laryngeal mask (I-gel) modified for mouth-to-mask ventilation after receiving brief on-site instruction.

SETTING

Entrance hall of a university hospital and the city campus of a public technical university, using a protected manikin scenario.

METHODS

Laypersons were handed a labelled, mouthpiece-integrated I-gel laryngeal mask and a corresponding instruction chart and were asked to follow the printed instructions.

OUTCOME MEASURES

The overall process was analysed and evaluated according to quality and duration.

RESULTS

Data from 100 participants were analysed. Overall, 79% of participants were able to effectively ventilate the manikin, 90% placed the laryngeal mask with the correct turn and direction, 19% did not position the mask deep enough and 85% believed that their inhibition threshold for performing resuscitation was lowered. A significant reduction in reluctance before and after the trial was found (p<0.0001). A total of 35% of participants had concerns about applying first aid in an emergency. Former basic life support (BLS) training significantly reduced the time of insertion (19.6 s, 95% CI 17.8 to 21.5, p=0.0004) and increased overall success (p=0.0096).

CONCLUSIONS

Laypersons were able to manage mouth-to-mask ventilation in the manikin with a reasonable success rate after receiving brief chart-based on-site instructions using a labelled I-gel mask. Positioning the mask deep enough and identifying whether the manikin was successfully ventilated were the main problems observed. A significant reduction in reluctance towards initialising BLS by using a modified supraglottic airway device (SAD) may lead to better acceptance of bystander resuscitation in laypersons, supporting the introduction of SADs into BLS courses and the stocking of SADs in units with public automatic external defibrillators.

Effect of mobile application-based versus DVD-based CPR training on students' practical CPR skills and willingness to act: a cluster randomised study

OBJECTIVES

The aim was to compare students' practical cardiopulmonary resuscitation (CPR) skills and willingness to perform bystander CPR, after a 30 min mobile application (app)-based versus a 50 min DVD-based training.

SETTINGS

Seventh grade students in two Swedish municipalities.

DESIGN

A cluster randomised trial. The classes were randomised to receive app-based or DVD-based training. Willingness to act and practical CPR skills were assessed, directly after training and at 6 months, by using a questionnaire and a PC Skill Reporting System. Data on CPR skills were registered in a modified version of the Cardiff test, where scores were given in 12 different categories, adding up to a total score of 12-48 points. Training and measurements were performed from December 2013 to October 2014.

PARTICIPANTS

63 classes or 1232 seventh grade students (13-year-old) were included in the study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary end point was the total score of the modified Cardiff test. The individual variables of the test and self-reported willingness to make a life-saving intervention were secondary end points.

RESULTS

The DVD-based group was superior to the app-based group in CPR skills; a total score of 36 (33-38) vs 33 (30-36) directly after training (p<0.001) and 33 (30-36) and 31 (28-34) at 6 months (p<0.001), respectively. At 6 months, the DVD group performed significantly better in 8 out of 12 CPR skill components. Both groups improved compression depth from baseline to follow-up. If a friend suffered cardiac arrest, 78% (DVD) versus 75% (app) would do compressions and ventilations, whereas only 31% (DVD) versus 32% (app) would perform standard CPR if the victim was a stranger.

CONCLUSIONS

At 6 months follow-up, the 50 min DVD-based group showed superior CPR skills compared with the 30 min app-based group. The groups did not differ in regard to willingness to make a life-saving effort.

Regional Variation in Out-of-Hospital Cardiac Arrest Survival in the United States

BACKGROUND

Although previous studies have shown marked variation in out-of-hospital cardiac arrest survival across US regions, factors underlying this survival variation remain incompletely explained.

METHODS AND RESULTS

Using data from the Cardiac Arrest Registry to Enhance Survival, we identified 96 662 adult patients with out-of-hospital cardiac arrest in 132 US counties. We used hierarchical regression models to examine county-level variation in rates of survival and survival with functional recovery (defined as Cerebral Performance Category score of 1 or 2) and examined the contribution of demographics, cardiac arrest characteristics, bystander cardiopulmonary resuscitation, automated external defibrillator use, and county-level sociodemographic factors in survival variation across counties. A total of 9317 (9.6%) patients survived to discharge, and 7176 (7.4%) achieved functional recovery. At a county level, there was marked variation in rates of survival to discharge (range, 3.4%-22.0%; median odds ratio, 1.40; 95% confidence interval, 1.32-1.46) and survival with functional recovery (range, 0.8%-21.0%; median odds ratio, 1.53; 95% confidence interval, 1.43-1.62). County-level rates of bystander cardiopulmonary resuscitation and automated external defibrillator use were positively correlated with both outcomes (P<0.0001 for all). Patient demographic and cardiac arrest characteristics explained 4.8% and 27.7% of the county-level variation in survival, respectively. Additional adjustment of bystander cardiopulmonary resuscitation and automated external defibrillator explained 41% of the survival variation, and this increased to 50.4% after adjustment of county-level sociodemographic factors. Similar findings were noted in analyses of survival with functional recovery.

CONCLUSIONS

Although out-of-hospital cardiac arrest survival varies significantly across US counties, a substantial proportion of the variation is attributable to differences in bystander response across communities.

Prognostic factors associated with hospital survival in comatose survivors of cardiac arrest

AIM: To identify patient, cardiac arrest and management factors associated with hospital survival in comatose survivors of cardiac arrest.

METHODS: A retrospective, single centre study of comatose patients admitted to our intensive care unit (ICU) following cardiac arrest during the twenty year period between 1993 and 2012. This study was deemed by the Human Research Ethics Committee (HREC) of Monash Health to be a quality assurance exercise, and thus did not require submission to the Monash Health HREC (Research Project Application, No. 13290Q). The study population included all patients admitted to our ICU between 1993 and 2012, with a discharge diagnosis including “cardiac arrest”. Patients were excluded if they did not have a cardiac arrest prior to ICU admission (i.e., if their primary arrest was during their admission to ICU), or were not comatose on arrival to ICU. Our primary outcome measure was survival to hospital discharge. Secondary outcome measures were ICU and hospital length of stay (LOS), and factors associated with survival to hospital discharge.

RESULTS: Five hundred and eighty-two comatose patients were admitted to our ICU following cardiac arrest, with 35% surviving to hospital discharge. The median ICU and hospital LOS was 3 and 5 d respectively. There was no survival difference between in-hospital and out-of-hospital cardiac arrests. Males made up 62% of our cardiac arrest population, were more likely to have a shockable rhythm (56% vs 37%, P < 0.001), and were more likely to survive to hospital discharge (40% vs 28%, P = 0.006). On univariate analysis, therapeutic hypothermia, regardless of method used (e.g., rapid infusion of ice cold fluids, topical ice, “Arctic Sun”, passive rewarming, “Bair Hugger”) and location initiated (e.g., pre-hospital, emergency department, intensive care) was associated with increased survival. There was however no difference in survival associated with target temperature, time at target temperature, location of initial cooling, method of initiating cooling, method of maintaining cooling or method of rewarming. Patients that survived were more likely to have a shockable rhythm (P < 0.001), shorter time to return of spontaneous circulation (P < 0.001), receive therapeutic hypothermia (P = 0.03), be of male gender (P = 0.006) and have a lower APACHE II score (P < 0.001). After multivariate analysis, only a shockable initial rhythm (OR = 6.4, 95%CI: 3.95-10.4; P < 0.01) and a shorter time to return of spontaneous circulation (OR = 0.95, 95%CI: 0.93-0.97; P < 0.01) was found to be independently associated with survival to hospital discharge.

CONCLUSION: In comatose survivors of cardiac arrest, shockable rhythm and shorter time to return of spontaneous circulation were independently associated with increased survival to hospital discharge.

Neuroprotective strategies and neuroprognostication after cardiac arrest

Neurocognitive disturbances are common among survivors of cardiac arrest (CA). Although initial management of CA, including bystander cardiopulmonary resuscitation, optimal chest compression, and early defibrillation, has been implemented continuously over the last years, few therapeutic interventions are available to minimize or attenuate the extent of brain injury occurring after the return of spontaneous circulation. In this review, we discuss several promising drugs that could provide some potential benefits for neurological recovery after CA. Most of these drugs have been investigated exclusively in experimental CA models and only limited clinical data are available. Further research, which also considers combined neuroprotective strategies that target multiple pathways involved in the pathophysiology of postanoxic brain injury, is certainly needed to demonstrate the effectiveness of these interventions in this setting. Moreover, the evaluation of neurological prognosis of comatose patients after CA remains an important challenge that requires the accurate use of several tools. As most patients with CA are currently treated with targeted temperature management (TTM), combined with sedative drug therapy, especially during the hypothermic phase, the reliability of neurological examination in evaluating these patients is delayed to 72-96 h after admission. Thus, additional tests, including electrophysiological examinations, brain imaging and biomarkers, have been largely implemented to evaluate earlier the extent of brain damage in these patients.

The pathophysiologies of asphyxial vs dysrhythmic cardiac arrest: implications for resuscitation and post-event management

BACKGROUND

Cardiac arrest is not a uniform condition and significant heterogeneity exists within all victims with regard to the cause of cardiac arrest. Primary cardiac (dysrhythmic) and asphyxial causes together are responsible for most cases of cardiac arrest at all age groups. The purpose of this article is to review the pathophysiologic differences between dysrhythmic and asphyxial cardiac arrest in the prearrest period, during the no-flow state, and after successful cardiopulmonary resuscitation.

METHODS

The electronic databases of PubMed/Medline, Scopus, and Cochrane were searched for relevant literature and studies.

RESULTS/DISCUSSION

Significant differences exist between dysrhythmic and asphyxial cardiac arrest regarding their pathophysiologic pathways and affect consequently the postresuscitation period. Laboratory data indicate that asphyxial cardiac arrest leads to more widespread postresuscitation brain damage compared with dysrhythmic cardiac arrest. Regarding postresuscitation myocardial dysfunction, few studies have addressed a comparison of the 2 conditions with controversial results.

CONCLUSIONS

Asphyxial cardiac arrest differs significantly from dysrhythmic cardiac arrest with regard to pathophysiologic mechanisms, neuropathologic damage, postresuscitation organ dysfunction, and response to therapy. Both conditions should be considered and treated in a different manner.