Differential survival for men and women from out-of-hospital cardiac arrest varies by age: results from the OPALS study

Gender Disparities in Out-of-hospital Cardiac Arrests

Background

Despite advances in resuscitation science and public health, out-of-hospital cardiac arrest (OOHCA) has an average survival rate of only 12% nationwide, compared to 24.8% of patients who suffer from cardiac arrest while in hospital. Additionally, gender is an important element of human health, and there is a clear pattern for gender-specific survivability in cardiac arrest. This study examined differences in presentations, treatment, management, and outcomes.

Aim

The primary focus of this study was to shed light on differences in presentations, treatments, and outcomes between men and women suffering from an out-of-hospital cardiac arrest and the accompanying contributing factors.

Methods

All emergency medical services-related data, including age, date, initial rhythm, chemical interventions (i.e., epinephrine, dextrose), blood glucose levels, defibrillations, endotracheal tube (ETT) attempts, final airway management, achievement of return of spontaneous circulation (ROSC), and the conclusion of the case up to the emergency department, were recorded using a standardized emergency medical services (EMS) charting record by the highest-ranking EMS provider on the ambulance. The reports were retrospectively collected and analyzed.

Conclusion

The study examined demographics, treatments rendered, and outcomes in OOHCA cases that occurred in a major United States (US) city in 2016. Several significant differences in care were noted between men and women. In general, women received less respiratory, chemical, and electrical interventions than men; however, statistically significant differences were only observed in the number of attempts of endotracheal intubations, number of doses of epinephrine per encounter, and number of defibrillations per encounter. In spite of generally receiving less care, women appeared to respond more favorably to cardiac arrest interventions, as demonstrated by higher rates of ROSC. Despite this, women were also found to be eight years older at the time of arrest. Future studies are needed to determine causality in discrepancies between the genders in addition to investigating differences in treatment in other areas of the United States.

Assessment of the 11-year nationwide trend of out-of-hospital cardiac arrest cases among elderly patients in Japan (2005-2015)

OBJECTIVE

Japan has one of the most rapidly aging societies worldwide. This study aimed to assess the long-term nationwide trend of out-of-hospital cardiac arrest (OHCA) cases among elderly patients in Japan.

METHODS

This prospective, nationwide observational study in Japan included elderly patients aged ≥65 years who experienced OHCA from January 1, 2005 to December 31, 2015. The patients were classified into three groups: young-old, aged 65-74 years; old-old, aged 75-84 years; and oldest-old, aged ≥85 years. The primary outcome of this study was one-month survival with a favorable neurological outcome, which was defined as a cerebral performance category scale score of 1 or 2.

RESULTS

A total of 877,009 patients were included in our analysis. The number of elderly patients with OHCA increased from 65,968 in 2005 to 87,339 in 2015, and each age category showed a significantly increasing trend (p value <0.001 for each trend). The proportions of favorable neurological outcomes also increased from 1.2% in 2005 to 2.8% in 2015 in the young-old group; from 0.6% in 2005 to 1.1% in 2015 in the old-old group; and from 0.2% in 2005 to 0.5% in 2014 in the oldest-old group. Furthermore, this improving trend was notable for those with a shockable first documented rhythm.

CONCLUSIONS

Based on this long-term nationwide observational study in Japan, the number of elderly patients with OHCA increased annually, and a significant improvement in the patients' neurological outcomes was noted regardless of age category, particularly among those with an initially shockable rhythm.

Gender and survival from out-of-hospital cardiac arrest: a New Zealand registry study

Objective

To determine the relationships between survival from all-cause out-of-hospital cardiac arrest (OHCA) and gender in New Zealand.

Methods

A retrospective observational study was conducted using data compliant with the Utstein guidelines from the St John New Zealand OHCA Registry for adult patients who were treated for an OHCA between 1 October 2013 and 30 September 2015. Univariate logistic regression was used to investigate factors associated with return of spontaneous circulation sustained to handover at hospital and survival to 30 days. Multivariate logistic regression models were used to investigate outcome differences in survival according to gender at 30 days postevent.

Results

Women survived to hospital handover in 29% of cases, which was not significantly different from men (31%). When adjusted for age, location, aetiology, initial rhythm and witnessed status, there was no significant difference in 30-day survival between men (16%) and women (13%) (adjusted OR 1.22, 95% CI (0.96 to 1.55), p=0.11).

Conclusion

No statistical differences were found in 30-day survival between genders when adjustments for unfavourable Utstein variables were accounted for.

The impact of sex and age on neurological outcomes in out-of-hospital cardiac arrest patients with targeted temperature management

Background

There are conflicting data regarding sex-based differences in the outcomes of out-of-hospital cardiac arrest (OHCA) patients, and whether the specific sex advantage is age-specific remains unclear. We assessed the impact of the interactions between sex and age on the neurological outcomes of OHCA patients receiving targeted temperature management (TTM).

Methods

Data collected from 2007 to 2012 for a multicenter, registry-based study of the Korean Hypothermia Network were analyzed. We used a multivariate logistic regression model with an interaction term (age × sex) as the final model for the outcomes. To evaluate the association between sex and outcome in specific age groups, all patients were divided into specific age subgroups, and the adjusted ORs and 95% CIs of good neurological outcomes for males were calculated for each age group. Finally, the ORs of a good neurological outcome for the specific age groups compared with the 50- to 59-year-old group were calculated for both sexes.

Results

In the interaction analysis, age was a negative prognostic factor (OR, 0.95 [95% CI, 0.93-0.98]), whereas sex was not associated with neurological outcomes (OR, 3.74 [95% CI, 0.85–16.35]), and reproductive age in females (age, < 50 years) was also not associated with good neurological outcomes. After the patients were divided into five age groups, sex was not an independent predictor of neurological outcomes across all age groups. Patients of both sexes aged < 40 years had significantly better outcomes than patients in the 50- to 59-year-old group (males, OR, 4.03 [95% CI, 1.86–8.73]; females, OR, 10.34 [95% CI, 1.99–53.85]). Males aged ≥ 70 years had significantly poorer neurological outcomes than those in the 50- to 59-year-old group (OR, 0.15 [95% CI, 0.07–0.32]), but this outcome was not observed for females (OR, 0.78 [95% CI, 0.20–3.14]).

Conclusions

Sex did not influence the neurological outcomes of TTM-treated OHCA patients. In contrast to the outcomes in males, the neurological outcomes of females worsened from 18 to 59 years of age and then remained constant.

Intravenous Fluid Administration and the Survival of Pre hospital Resuscitated out of Hospital Cardiac Arrest Patients in Thailand

Introduction

Out of Hospital Cardiac Arrest (OHCA) is a leading cause of death worldwide. The Emergency Medical Service (EMS) provides early care to critical OHCA patients. Pre hospital intervention has been improving OHCA survival rate, however it is still unclear for the recommendation of routine infusion of Intravenous (IV) fluids during cardiac arrest resuscitation.

Aim

This study aimed to determine whether IV fluid administration was associated with increasing survival of resuscitated OHCA patients and to assess the survival rate of resuscitated OHCA patients.

Materials and Methods

This cross-sectional analytical study was conducted among 33,006 resuscitated OHCA patients who received emergency medical service in Thailand. Data set from the EMS Registry of the OHCA patients who received Advanced Life Support (ALS) and Cardiopulmonary Resuscitation (CPR) during January 2011 to December 2015 was enrolled as per inclusion criteria. Data were analysed by using both descriptive statistic and multiple logistic regression.

Results

The result indicated that 27,270 OHCA patients (82.62%:95%CI=82.121-83.030%) survived until they reached hospital. In addition, after adjusting for effect modifiers and covariates, it was found that adult (≥18 years) with IV fluid administration were more likely to survive (adjusted OR=4.389; 95% CI: 3.911-4.744) when compared to children (<18 years) with IV fluid administration (adjusted OR =2.952; 95% CI: 2.040-4.273). Other factors associated with OHCA patients' survival were female gender (adjusted OR =1.151; 95% CI: 1.067-1.241), response time per minutes (adjusted OR =0.993; 95% CI: 0.989-0.997), scene time per minutes (adjusted OR=0.948; 95% CI: 0.944-0.952) and transport time per minutes (adjusted OR=0.973, 95%CI: 0.968-0.978).

Conclusion

This study revealed that IV fluid administration was significantly associated with survival of OHCA patients while controlled other covariates including female gender, response time, scene time and transport time. Therefore, it is recommended that the IV fluid administration should be medicated for resuscitated OHCA patients.

Age × Gender Interaction Effect on Resuscitation Outcomes in Patients With Out-of-Hospital Cardiac Arrest

Although an interaction between gender and age has been shown to influence resuscitation outcomes in patients with out-of-hospital cardiac arrest (OHCA), this interaction has not been investigated in Asian populations. In this prospective, observational study, data from all cases of OHCA in Japan between 2005 and 2012 were obtained from the Japanese National Registry. We determined the relative excess risk due to interaction and the ratio of odds ratios (ORs) to assess the interaction effect of gender and age on the incidence of return of spontaneous circulation (ROSC) before hospital arrival, 1-month survival, and neurologically intact survival 1 month after OHCA. Male gender was associated with decreased ROSC and lower 1-month survival rates in patients with OHCA of presumed cardiac origin. Older age was associated with lower 1-month and neurologically intact survival rates in male patients with OHCA of presumed cardiac and noncardiac origin and with increased ROSC in male patients with OHCA of presumed cardiac origin. The relative excess risk due to interaction for ROSC in patients with OHCA of presumed cardiac origin was statistically significant (OR 0.19, 95% confidence interval [CI] 0.06 to 0.32). The ratio of ORs for ROSC was statistically significant in patients with OHCA of presumed cardiac origin (OR 1.25, 95% CI 1.05 to 1.47) and of noncardiac origin (OR 0.40, 95% CI 0.17 to 0.92). In conclusion, the interaction effect between age and gender on ROSC was positive in OHCA cases of presumed cardiac origin and negative in those of noncardiac origin.

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.

Atrial Fibrillation and Ventricular Arrhythmias: Sex Differences in Electrophysiology, Epidemiology, Clinical Presentation, and Clinical Outcomes

Sex-specific differences in the epidemiology, pathophysiology, clinical presentation, clinical treatment, and clinical outcomes of atrial fibrillation (AF), sustained ventricular arrhythmias, and sudden cardiac death are recognized. Sex hormones cause differences in cardiac electrophysiological parameters between men and women that may affect the risk for arrhythmias. The incidence and prevalence of AF is lower in women than in men. However, because women live longer and AF prevalence increases with age, the absolute number of women with AF exceeds that of men. Women with AF are more symptomatic, present with more atypical symptoms, and report worse quality of life in comparison with men. Female sex is an independent risk factor for death or stroke attributable to AF. Oral anticoagulation therapy for stroke prevention has similar efficacy for men and women, but older women treated with warfarin have a higher residual risk of stroke in comparison with men. Women with AF are less likely to receive rhythm control antiarrhythmic drug therapy, electric cardioversion, or catheter ablation in comparison with men. The incidence and prevalence of sustained ventricular arrhythmias and sudden cardiac death are lower in women than in men. Women receiving implantable cardioverter defibrillators for primary prevention of sudden cardiac death are less likely to experience sustained ventricular arrhythmias in comparison with men. In contrast, women receiving a cardiac resynchronization therapy implantable cardioverter defibrillator for the treatment of heart failure are more likely to benefit than men. Women are less likely to be referred for implantable cardioverter defibrillator therapy despite current guideline recommendations. Women are more likely to experience a significant complication related to implantable cardioverter defibrillator implantation in comparison with men. Whether sex differences in treatment decisions reflect patient preferences or treatment biases requires further study.

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.

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.

New Developments in the Treatment of Acute Myocardial Infarction Associated with Out-of-Hospital Cardiac Arrest. A Review

Out-of-hospital cardiac arrest (OHCA) occurring as the first manifestation of an acute myocardial infarction is associated with very high mortality rates. As in comatose patients the etiology of cardiac arrest may be unclear, especially in cases without ST-segment elevation on the surface electrocardiogram, the decision to perform or not to perform urgent coronary angiography can have a significant impact on the prognosis of these patients. This review summarises the current knowledge and recommendations for treating patients with acute myocardial infarction presenting with OHCA. New therapeutic measures for the post-resuscitation phase are presented, such as hypothermia or extracardiac life support, together with strategies aiming to restore the coronary flow in the resuscitation phase using intra-arrest percutaneous revascularization performed during resuscitation. The role of regional networks in providing rapid access to the hospital facilities and to a catheterization laboratory for these critical cardiovascular emergencies is described.

A Clinical Trial Simulation Evaluating Epinephrine Pharmacokinetics at various Dosing Frequencies during Cardiopulmonary Resuscitation

OBJECTIVE

This article seeks to test the hypothesis that repeated 1mg intravenous epinephrine dosing intervals of 3-minutes and 5-minutes results in differences in the total drug exposure and the maximum epinephrine concentration using simulated cardiopulmonary resuscitation (CPR) dosing.

METHODS

Published population pharmacokinetic parameters were identified in the literature and pharmacokinetic dosing simulations were conducted according to the 2015 American Heart Association guidelines for CPR in adults. The stochastic pharmacokinetic simulations were conducted in MATLAB and R for statistical programming.

RESULTS

A total of 5000 simulations were conducted in MATLAB while 90,000 data points for the 3-minute dosing interval and 150,000 data points for the 5-minute epinephrine dosing interval resulted from pharmacokinetic simulations in R. The difference between the 3-minute and 5-minute dosing intervals for patients with a SAP score of 30, were found to be: Male ΔAUC=2416 and ΔCmax=71, Female ΔAUC=1422 and ΔCmax=41, and for a 70kg patient ΔAUC=2968 and ΔCmax=90. While in virtual healthy participants, the differences were calculated to be ΔAUC=2658 and ΔCmax=81 for 3-minute and 5-minute dosing frequencies.

CONCLUSIONS

Epinephrine plasma levels during a simulated CPR scenario in a virtual patient population are dependent upon intravenous dosing intervals of either 3-minutes or 5-minutes. Based on the results of this clinical trial simulation, implications may exist that may require clinical studies investigating the influence of the 1mg epinephrine dosing frequency on the return of spontaneous circulation.

Sex and Age Aspects in Patients Suffering From Out-Of-Hospital Cardiac Arrest: A Retrospective Analysis of 760 Consecutive Patients

Cardiopulmonary resuscitation (CPR) is indicated in patients suffering from out-of-hospital cardiac arrest. Several studies suggest a sex- and age-based bias in the treatment of these patients. This particular bias may have a significant impact on the patient's outcome. However, the reasons for these findings are still unclear and discussed controversially. Therefore, the aim of this study was to retrospectively analyze treatment and out-of-hospital survival rates for potential sex- and age-based differences in patients requiring out-of-hospital CPR provided by an emergency physician in the city of Zurich, Switzerland.A total of 3961 consecutive patients (2003-2009) were included in this retrospective analysis to determine the frequency of out-of-hospital CPR and prehospital survival rate, and to identify potential sex- and age-based differences regarding survival and treatment of the patients.Seven hundred fifty-seven patients required CPR during the study period. Seventeen patients had to be excluded because of incomplete or inconclusive documentation, resulting in 743 patients (511 males, 229 females) undergoing further statistical analysis. Female patients were significantly older, compared with male patients (68 ± 18 [mean ± SD] vs 64 ± 18 years, P = .012). Men were resuscitated slightly more often than women (86.4% vs 82.1%). Overall out-of-hospital mortality rate was found to be 81.2% (492/632 patients) with no differences between sexes (82.1% for males vs 79% for females, odds ratio 1.039, 95% confidence interval 0.961-1.123). No sex differences were detected in out-of-hospital treatment, as assessed by the different medications administered, initial prehospital Glasgow Coma Scale, and prehospital suspected leading diagnosis.The data of our study demonstrate that there was no sex-based bias in treating patients requiring CPR in the prehospital setting in our physician-led emergency ambulance service.

The UK Out of Hospital Cardiac Arrest Outcome (OHCAO) project

INTRODUCTION

Reducing premature death is a key priority for the UK National Health Service (NHS). NHS Ambulance services treat approximately 30 000 cases of suspected cardiac arrest each year but survival rates vary. The British Heart Foundation and Resuscitation Council (UK) have funded a structured research programme--the Out of Hospital Cardiac Arrest Outcomes (OHCAO) programme. The aim of the project is to establish the epidemiology and outcome of OHCA, explore sources of variation in outcome and establish the feasibility of setting up a national OHCA registry.

METHODS AND ANALYSIS

This is a prospective observational study set in UK NHS Ambulance Services. The target population will be adults and children sustaining an OHCA who are attended by an NHS ambulance emergency response and where resuscitation is attempted. The data collected will be characterised broadly as system characteristics, emergency medical services (EMS) dispatch characteristics, patient characteristics and EMS process variables. The main outcome variables of interest will be return of spontaneous circulation and medium-long-term survival (30 days to 10-year survival).

ETHICS AND DISSEMINATION

Ethics committee permissions were gained and the study also has received approval from the Confidentiality Advisory Group Ethics and Confidentiality committee which provides authorisation to lawfully hold identifiable data on patients without their consent. To identify the key characteristics contributing to better outcomes in some ambulance services, reliable and reproducible systems need to be established for collecting data on OHCA in the UK. Reports generated from the registry will focus on data completeness, timeliness and quality. Subsequent reports will summarise demographic, patient, process and outcome variables with aim of improving patient care through focus quality improvement initiatives.

Mechanical chest compression does not seem to improve outcome after out-of hospital cardiac arrest. A single center observational trial

AIM

Recently three large post product placement studies, comparing mechanical chest compression (cc) devices to those who received manual cc, found equivalent outcome results for both groups. Thus the question arises whether those results could be replicated using the devices on a daily routine.

METHODS

We prospectively enrolled 948 patients over a 12 months period. Chi-Square test and Mann-Whitney-U test were used to assess differences between "manual" and "mechanical" cc subgroups. Uni- and multivariate Cox regression hazard analysis were used to assess the influence of cc type on survival.

RESULTS

A mechanical cc device was used in 30.1% (n=283) cases. Patients who received mechanical cc had a significantly worse neurological outcome - measured in cerebral performance category (CPC) - than the manual cc group (56.8% vs. 78.6%, p=0.009). Patients receiving mechanical cc were significantly younger, more were male and were more likely to have bystander CPR and an initially shock-able ECG rhythm. There was no difference in the quality of CPR that might explain the worse outcome in mechanical cc patients.

CONCLUSION

Even with high quality CPR in both, manual and mechanical cc groups, outcome in patients who received mechanical cc was significantly worse. The anticipated benefits of a higher compression ratio and a steadier compression depth of a mechanical cc device remain uncertain. In this study selection for mechanical cc was not standardized, and was non-random. This merits further investigation. Further research on how mechanical cc is chosen and used should be considered.

CLINICAL TRIAL REGISTRATION

https://ekmeduniwien.at/core/catalog/2013/ (EK-Nr:1221/2013).