The increased mortality from witnessed out-of-hospital cardiac arrest in the home

Robust prognostic prediction model developed with integrated biological markers for acute myocardial infarction

Commonly used prediction methods for acute myocardial infarction (AMI) were created before contemporary percutaneous coronary intervention was recognized as the primary therapy. Although several studies have used machine learning techniques for prognostic prediction of patients with AMI, its clinical application has not been achieved. Here, we developed an online application tool using a machine learning model to predict in-hospital mortality in patients with AMI. A total of 2,553 cases of ST-elevation AMI were assigned to 80% training subset for cross validation and 20% test subset for model performance evaluation. We implemented random forest classifier for the binary classification of in-hospital mortality. The selected best feature set consisted of ten clinical and biological markers including max creatine phosphokinase, hemoglobin, heart rate, creatinine, systolic blood pressure, blood sugar, age, Killip class, white blood cells, and c-reactive protein. Our model achieved high performance: the area under the curve of the receiver operating characteristic curve for the test subset, 0.95: sensitivity, 0.89: specificity, 0.91: precision, 0.43: accuracy, 0.91 respectively, which outperformed common scoring methods. The freely available application tool for prognostic prediction can contribute to risk triage and decision-making in patient-centered modern clinical practice for AMI.

Association between sex and survival after non-traumatic out of hospital cardiac arrest: A systematic review and meta-analysis

BACKGROUND

Existing studies have shown conflicting results regarding the relationship of sex with survival after out of hospital cardiac arrest (OHCA). This systematic review evaluates the association of female sex with survival to discharge and survival to 30 days after non-traumatic OHCA.

METHODS

We searched Medline, Embase, CINAHL, Web of Science, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews from inception through June 2021 for studies evaluating female sex as a predictor of survival in adult patients with non-traumatic cardiac arrest. Random-effects inverse variance meta-analyses were performed to calculate pooled odds ratios (ORs) with 95% confidence intervals (CI). The GRADE approach was used to assess evidence quality.

RESULTS

Thirty studies including 1,068,788 patients had female proportion of 41%. There was no association for female sex with survival to discharge (OR 1.03, 95% CI 0.95-1.12; I²=89%). Subgroup analysis of low risk of bias studies demonstrated increased survival to discharge for female sex (OR 1.20, 95% CI 1.18-1.23; I²=0%) and with high certainty, the absolute increase in survival was 2.2% (95% CI 0.1%-3.6%). Female sex was not associated with survival to 30 days post-OHCA (OR 1.02, 95% CI 0.92-1.14; I²=79%).

CONCLUSIONS

In adult patients experiencing OHCA, with high certainty in the evidence from studies with low risk of bias, female sex had a small absolute difference for the outcome survival to discharge and no difference in survival at 30 days. Future models that aim to stratify risk of survival post-OHCA should focus on sex-specific factors as opposed to sex as an isolated prognostic factor.

Targeting relatives: Impact of a cardiac rehabilitation programme including basic life support training on their skills and attitudes

Background

Training families of patients at risk for sudden cardiac death in basic life support (BLS) has been recommended, but remains challenging. This research aimed to determine the impact of embedding resuscitation training for patients in a cardiac rehabilitation programme on relatives' BLS skill retention at six months.

Design

Intervention community study.

Methods

Relatives of patients suffering acute coronary syndrome or revascularization enrolled on an exercise-based cardiac rehabilitation programme were included. BLS skills of relatives linked to patients in a resuscitation-retraining programme (G-CPR) were compared with those of relatives of patients in a standard programme (G-Stan) at baseline, following brief instruction and six months after. Differences in skill performance and deterioration and self-perceived preparation between groups over time were assessed.

Results

Seventy-nine relatives were included and complete data from 66 (G-Stan=33, G-CPR=33) was analysed. Baseline BLS skills were equally poor, improved irregularly following brief instruction and decayed afterwards. G-CPR displayed six-month better performance and lessened skill deterioration over time compared with G-Stan, including enhanced compliance with the BLS sequence ( p = 0.006 for group*time interaction) and global resuscitation quality ( p = 0.007 for group*time interaction). Self-perceived preparation was higher in G-CPR ( p = 0.002).

Conclusions

Relatives of patients suffering acute coronary syndrome or revascularization enrolled on a cardiac rehabilitation programme showed poor BLS skills. A resuscitation-retraining cardiac rehabilitation programme resulted in relatives' higher BLS awareness, skill retention and confidence at six months compared with the standard programme. This may suggest a significant impact of this formula on the family setting and support the active role of patients to enhance health education in their environment.

Determining the motivations of family members to undertake cardiopulmonary resuscitation training through grounded theory

AIMS

To explore the motivation of family members of patients at high risk for sudden cardiac death for undertaking cardiopulmonary resuscitation (CPR) training.

BACKGROUND

Home cardiac arrests are associated with poor outcomes because few family members learn CPR. Little is known about factors that motivate family members to participate in CPR training.

DESIGN

We used grounded theory to establish a theoretical framework to explore the motivational factors for learning CPR among family members.

METHODS

Twelve participant observations and 42 semi-structured interviews with family members of different behaviours towards CPR training were conducted from December 2013 - November 2016. Data were analysed using constant-comparisons, situational analysis, and encoding.

FINDINGS

A motivation-behaviour theoretical framework for learning CPR was constructed. We identified meeting inner needs as the core category to demonstrate motivation. Security motivation and responsibility motivation emerged as main categories, which demonstrate that seeking a sense of security and shouldering family responsibility were important considerations for family members to learn CPR. These two motivations produced high-engagement behaviours of family members to learn CPR.

CONCLUSIONS

The motivations we identified-deriving from a sense of security and family responsibility-are the main reasons family members would learn CPR and, therefore, should be understood by medical professionals. Understanding these motivations may help in the formulation of customized CPR training that further meets the needs of family members. For example, motivational interventions that are integrated with a family-based CPR course can be designed to improve the participation of family members and the sustainability of the course.

Out-of-hospital cardiac arrest in the home: Can area characteristics identify at-risk communities in the Republic of Ireland?

Background

Internationally, the majority of out-of-hospital cardiac arrests where resuscitation is attempted (OHCAs) occur in private residential locations i.e. at home. The prospect of survival for this patient group is universally dismal. Understanding of the area-level factors that affect the incidence of OHCA at home may help national health planners when implementing community resuscitation training and services.

Methods

We performed spatial smoothing using Bayesian conditional autoregression on case data from the Irish OHCA register. We further corrected for correlated findings using area level variables extracted and constructed for national census data.

Results

We found that increasing deprivation was associated with increased case incidence. The methodology used also enabled us to identify specific areas with higher than expected case incidence.

Conclusions

Our study demonstrates novel use of Bayesian conditional autoregression in quantifying area level risk of a health event with high mortality across an entire country with a diverse settlement pattern. It adds to the evidence that the likelihood of OHCA resuscitation events is associated with greater deprivation and suggests that area deprivation should be considered when planning resuscitation services. Finally, our study demonstrates the utility of Bayesian conditional autoregression as a methodological approach that could be applied in any country using registry data and area level census data.

Electronic supplementary material

The online version of this article (10.1186/s12942-018-0126-z) contains supplementary material, which is available to authorized users.

Mortality after out-of-hospital cardiac arrest in a Spanish Region

AIMS

To determine out-of-hospital cardiac arrest mortality in the province of Alicante (Spain) and its associated factors.

METHODS

Cross-sectional observational study of all patients who received cardiopulmonary resuscitation (CPR) by the Emergency Medical Services (EMS) (n = 422) in the province of Alicante in 2013. To determine associated factors, a binary logistic regression model was constructed. Primary outcome: death before arriving at the hospital. Predictive variables: gender, age, artificial respiration, prior functional status, asystole, cardiogenic aetiology, bystander CPR, time from the cardiac arrest to the arrival of the EMS and location of cardiac arrest.

RESULTS

There were 337 deaths (79.9%; 95% CI: 76.0-83.7%). Factors independently associated (p<0.05) with death were: male gender (OR = 2.11; 95% CI: 1.20-3.72; p = 0.010), asystole (OR = 1.99, 95% CI: 1.17-3.39; p = 0.012), cardiac arrest at home (OR = 2.44; 95% CI: 1.42-4.18; p = 0.001) and an increased time between arrest and EMS arrival (OR = 1.05, 95% CI: 1.01-1.09, p = 0.009). Having a worse prior functional status had a tendency towards significance (OR = 0.56, 95% CI: 0.31-1.02, p = 0.059).

CONCLUSIONS

Mortality was high. The associated factors were: male gender, asystole, worse prior functional status, longer time from the cardiac arrest to the arrival of the EMS and having the cardiac arrest at home. The clearly negative impact of experiencing a cardiac arrest at home necessitates modifying training policies in Spain. These policies should be focused on providing information about CPR in schools in order to decrease the mortality of these events.

A Simple Risk Stratification Model for ST-Elevation Myocardial Infarction (STEMI) from the Combination of Blood Examination Variables: Acute Myocardial Infarction-Kyoto Multi-Center Risk Study Group

Background

Many mortality risk scoring tools exist among patients with ST-elevation Myocardial Infarction (STEMI). A risk stratification model that evaluates STEMI prognosis more simply and rapidly is preferred in clinical practice.

Methods and Findings

We developed a simple stratification model for blood examination by using the STEMI data of AMI-Kyoto registry in the derivation set (n = 1,060) and assessed its utility for mortality prediction in the validation set (n = 521). We selected five variables that significantly worsen in-hospital mortality: white blood cell count, hemoglobin, C-reactive protein, creatinine, and blood sugar levels at >10,000/μL, <10 g/dL, >1.0 mg/dL, >1.0 mg/dL, and >200 mg/dL, respectively. In the derivation set, each of the five variables significantly worsened in-hospital mortality (p < 0.01). We developed the risk stratification model by combining laboratory variables that were scored based on each beta coefficient obtained using multivariate analysis and divided three laboratory groups. We also found a significant trend in the in-hospital mortality rate for three laboratory groups. Therefore, we assessed the utility of this model in the validation set. The prognostic discriminatory capacity of our laboratory stratification model was comparable to that of the full multivariable model (c-statistic: derivation set vs validation set, 0.81 vs 0.74). In addition, we divided all cases (n = 1,581) into three thrombolysis in myocardial infarction (TIMI) risk index groups based on an In TIME II substudy; the cases were further subdivided based on this laboratory model. The high laboratory group had significantly high in-hospital mortality rate in each TIMI risk index group (trend of in-hospital mortality; p < 0.01).

Conclusions

This laboratory stratification model can predict in-hospital mortality of STEMI simply and rapidly and might be useful for predicting in-hospital mortality of STEMI by further subdividing the TIMI risk index.

Video-Only Cardiopulmonary Resuscitation Education for High-Risk Families Before Hospital Discharge: A Multicenter Pragmatic Trial

BACKGROUND

Cardiopulmonary resuscitation (CPR) training rates in the United States are low, highlighting the need to develop CPR educational approaches that are simpler, with broader dissemination potential. The minimum training required to ensure long-term skill retention remains poorly characterized. We compared CPR skill retention among laypersons randomized to training with video-only (VO; no manikin) with those trained with a video self-instruction kit (VSI; with manikin). We hypothesized that VO training would be noninferior to the VSI approach with respect to chest compression (CC) rate.

METHODS AND RESULTS

We performed a prospective, cluster randomized trial of CPR education for family members of patients with high-risk cardiac conditions on hospital cardiac units, using a multicenter pragmatic design. Eight hospitals were randomized to offer either VO or VSI training before discharge using volunteer trainers. CPR skills were assessed 6 months post training. Mean CC rate among those trained with VO compared with those trained with VSI was assessed with a noninferiority margin set at 8 CC per min; as a secondary outcome, mean differences in CC depth were assessed. From February 2012 to May 2015, 1464 subjects were enrolled and 522 subjects completed a skills assessment. The mean CC rates were 87.7 (VO) CC per min and 89.3 (VSI) CC per min; we concluded noninferiority for VO based on a mean difference of -1.6 (90% confidence interval, -5.2 to 2.1). The mean CC depth was 40.2 mm (VO) and 45.8 mm (VSI) with a mean difference of -5.6 (95% confidence interval, -7.6 to -3.7). Results were similar after multivariate regression adjustment.

CONCLUSIONS

In this large, prospective trial of CPR skill retention, VO training yielded a noninferior difference in CC rate compared with VSI training. CC depth was greater in the VSI group. These findings suggest a potential trade-off in efforts for broad dissemination of basic CPR skills; VO training might allow for greater scalability and dissemination, but with a potential reduction in CC depth.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01514656.

[Epidemiological characteristics of out-of-hospital cardiorespiratory arrest recorded by the 061 emergencies system (SAMU) in the Balearic Islands (Spain), 2009-2012]

OBJECTIVE

To describe the epidemiology of out-of-hospital cardiorespiratory arrest (OHCA) and identify factors associated with recovery of spontaneous circulation (ROSC).

DESIGN

Observational study of OHCA registered on a continuous basis in the Emergency Medical Services (EMS) database during 2009-2012.

SETTING

The islands of Mallorca, Ibiza, Menorca and Formentera (Balearic Islands, Spain).

PATIENTS

OHCA in patients ≥ 18 years of age. The main variables were: Patient sex, age, probable cause, place of arrest, bystander, witnessed, basic life support (BLS), shockable rhythm, intervention time, semi-automatic defibrillator (AED), duration of cardiopulmonary arrest (CA), and ROSC. Independent variables were defined according to the Utstein protocol, and the dependent variable was defined as ROSC.

RESULTS

The EMS treated 1170 OHCAs (28/100,000 persons-year). We included 1130 CA. The mean age was 61.4 years (73.4% males). Most CA (72.3%) were of cardiac etiology, and 84.7% were witnessed. A total of 840 (74.3%) received BLS and 400 (47.6%) did so before arrival of the EMS (45 by bystander relatives). AED was available in 330 cases CA (29.2%) (96 with shockable rhythm). The interval between emergency call and BLS and between emergency call and advanced life support was 8.4 and 15.8min, respectively. Shockable rhythm was monitored in 257 CAs (22.7%). ROSC occurred in 261 (23.1%). Factors associated with ROSC were age, shockable rhythm, BLS before EMS arrival, and CA duration less than 30min.

CONCLUSION

The incidence rate of the OHCA is low. The proportion of patients receiving BLS from relatives was low. Age, shockable rhythm and BSL before EMS arrival were associated with ROSC.

Cardiac arrest management in general practice in Ireland: a 5-year cross-sectional study

OBJECTIVE

To document the involvement of general practitioners (GPs) in cardiac arrests with resuscitation attempts (CARAs) and to describe the outcomes.

DESIGN

A 5-year prospective cross-sectional study of GPs in Ireland equipped with automated external defibrillators (AEDs) and immediate care training by the MERIT Project, with data collection every 3 months over the 5-year period. Practices reported CARAs by quarterly survey with an 89% mean response rate (81-97% for the period).

SETTING

General practices throughout Ireland.

PARTICIPANTS

495 GP participated: 168 (33.9%) urban, 163 (32.9%) rural and 164 (33.1%) mixed.

INTERVENTIONS

All participating practices received a standard AED and basic life support kit. Training in immediate care was provided for at least one GP in the practice.

MAIN OUTCOME MEASURES

Incidence of CARA in participating practices. Return of spontaneous circulation (ROSC) and discharge alive from hospital.

RESULTS

36% of practices were involved in a CARA during the 5-year period and 13% were involved in more than one CARA. Of the 272 CARAs reported, ROSC occurred in 32% (87/272) and discharge from hospital in 18.7% (49/262). In 45% of cases, the first AED was brought by the GP and in 65%, the GP arrived before the ambulance service. More cases occurred in rural and mixed settings than urban ones, but the survival rates did not differ between areas. In 65% of cases, the GP was on duty at the time of the incident and 47% of cases occurred in the patient's home.

CONCLUSIONS

These outcomes are comparable with more highly structured components of the emergency response system and indicate that GPs have an important role to play in the care of patients in their own communities. GPs experience cardiac arrest cases during the course of their daily work and provide prompt care which results in successful outcomes in urban, mixed and rural settings.

Factors associated with mortality in out-of-hospital cardiac arrests attended in basic life support units in the Basque Country (Spain)

INTRODUCTION AND OBJECTIVES

To describe the epidemiological characteristics of cardiac arrests attended in basic life support units in the Basque Country (Spain) and look for factors associated with failure of cardiopulmonary resuscitation.

METHODS

We conducted an observational study during 18 months, including all out-of-hospital cardiopulmonary resuscitation provided by basic life support units. The variables defined in the Utstein-style were considered as independent and mortality as the dependent variable. We applied descriptive and analytical statistics and evaluated the magnitude of the association using a logistic regression model, which included variables with P<.05 in the bivariate analysis.

RESULTS

Of 1050 cardiac arrests attended, 15.7% of patients were revived in situ. The presumed etiology was cardiac in 55.3% of cases and 71.4% occurred at home. Cardiopulmonary resuscitation was started before the arrival of the ambulance in 22.9% of cases and in 18.2% the rhythm of presentation was shockable. Variables associated with lower mortality were: shockable rhythms (relative risk=0.44; P=.003), patient aged<65 years (relative risk=0.44; P=.002), time to cardiopulmonary resuscitation<8 min (relative risk=0.56; P=.039), and out-of-home events (relative risk=0.55; P=.031).

CONCLUSIONS

Cardiac arrest survival was low. Cardiopulmonary resuscitation before the arrival of the ambulance was rare. A shockable rhythm, age younger than 65 years, early cardiopulmonary resuscitation efforts, and a location away from home were associated with longer survival. It is necessary to develop strategies designed to reduce ambulance response time and educate the public in basic resuscitation.

Elderly out-of-hospital cardiac arrest has worse outcomes with a family bystander than a non-family bystander

BACKGROUND

A growing elderly population along with advances in equipment and approaches for pre-hospital resuscitation necessitates up-to-date information when developing policies to improve elderly out-of-hospital cardiac arrest (OHCA) outcomes. We examined the effects of bystander type (family or non-family) intervention on 1-month outcomes of witnessed elderly OHCA patients.

METHODS

Data from a total of 85,588 witnessed OHCA events in patients aged ≥65 years, which occurred from 2005 to 2008, were obtained from a nationwide population-based database. Patients were stratified into three age categories (65-74, 75-84, ≥85 years), and the effects of bystander type (family or non-family) on initial cardiac rhythm, rate of bystander cardiopulmonary resuscitation (CPR), and 1-month outcomes were assessed.

RESULTS

The overall survival rate was 6.9% (65-74 years: 9.8%, 75-84 years: 6.9%, ≥85 years: 4.6%). Initial VF/VT was recorded in 11.1% of cases with a family bystander and 12.9% of cases with a non-family bystander. The rate of bystander CPR was constant across the age categories in patients with a family bystander and increased with advancing age categories in patients with a non-family bystander. Patients having a non-family bystander were associated with significantly higher 1-month rates of survival (OR: 1.26; 95% CI: 1.19-1.33) and favorable neurological status (OR: 1.47; 95% CI: 1.34-1.60).

CONCLUSIONS

Elderly patient OHCA events witnessed by a family bystander were associated with worse 1-month outcomes than those witnessed by a non-family bystander. Healthcare providers should consider targeting potential family bystanders for CPR education to increase the rate and quality of bystander CPR.

Comparison of emergency medical services systems across Pan-Asian countries: a Web-based survey

BACKGROUND

There are great variations in out-of-hospital cardiac arrest (OHCA) survival outcomes among different countries and different emergency medical services (EMS) systems. The impact of different systems and their contribution to enhanced survival are poorly understood. This paper compares the EMS systems of several Asian sites making up the Pan-Asian Resuscitation Outcomes Study (PAROS) network. Some preliminary cardiac arrest outcomes are also reported.

METHODS

This is a cross-sectional descriptive survey study addressing population demographics, service levels, provider characteristics, system operations, budget and finance, medical direction (leadership), and oversight.

RESULTS

Most of the systems are single-tiered. Fire-based EMS systems are predominant. Bangkok and Kuala Lumpur have hospital-based systems. Service level is relatively low, from basic to intermediate in most of the communities. Korea, Japan, Singapore, and Bangkok have intermediate emergency medical technician (EMT) service levels, while Taiwan and Dubai have paramedic service levels. Medical direction and oversight have not been systemically established, except in some communities. Systems are mostly dependent on public funding. We found variations in available resources in terms of ambulances and providers. The number of ambulances is 0.3 to 3.2 per 100,000 population, and most ambulances are basic life support (BLS) vehicles. The number of human resources ranges from 4.0 per 100,000 population in Singapore to 55.7 per 100,000 population in Taipei. Average response times vary between 5.1 minutes (Tainan) and 22.5 minutes (Kuala Lumpur).

CONCLUSION

We found substantial variation in 11 communities across the PAROS EMS systems. This study will provide the foundation for understanding subsequent studies arising from the PAROS effort.