There is a difference in characteristics and outcome between women and men who suffer out of hospital cardiac arrest

Sex-Related Differences in Utilization and Outcomes of Extracorporeal Cardio-Pulmonary Resuscitation for Refractory Cardiac Arrest

Sparse data exist on sex-related differences in extracorporeal cardiopulmonary resuscitation (ECPR) for refractory cardiac arrest (rCA). We explored the role of sex on the utilization and outcomes of ECPR for rCA by retrospective analysis of the Extracorporeal Life Support Organization (ELSO) International Registry. The primary outcome was in-hospital mortality. Exploratory outcomes were discharge disposition and occurrence of any specific extracorporeal membrane oxygenation (ECMO) complications. From 1992 to 2020, a total of 7,460 adults with ECPR were identified: 30.5% women; 69.5% men; 55.9% Whites, 23.7% Asians, 8.9% Blacks, and 3.8% Hispanics. Women's age was 50.4 ± 16.9 years (mean ± standard deviation) and men's 54.7 ± 14.1 (p < 0.001). Ischemic heart disease occurred in 14.6% women vs. 18.5% men (p < 0.001). Overall, 28.5% survived at discharge, 30% women vs. 27.8% men (p = 0.138). In the adjusted analysis, sex was not associated with in-hospital mortality (odds ratio [OR] = 0.93 [confidence interval {CI} = 0.80-1.08]; p = 0.374). Female sex was associated with decreased odds of neurologic, cardiovascular, and renal complications. Despite being younger and having fewer complications during ECMO, women had in-hospital mortality similar to men. Whether these findings are driven by biologic factors or disparities in health care warrants further investigation.

Sex differences among patients presenting to hospital with out-of-hospital cardiac arrest and shockable rhythm

OBJECTIVE

Sex differences in patients presenting with out-of-hospital cardiac arrest (OHCA) and shockable rhythm might be associated with disparities in clinical outcomes.

METHODS

We conducted a retrospective cohort study and compared characteristics and short-term outcomes between male and female adult patients who presented with OHCA and shockable rhythm at two large metropolitan health services in Melbourne, Australia between the period of 2014-2018. Logistic regression was used to assess the effect of sex on clinical outcomes.

RESULTS

Of 212 patients, 166 (78%) were males and 46 (22%) were females. Both males and females presented with similar rates of ST-elevation myocardial infarction (44% vs 36%, P = 0.29), although males were more likely to have a history of coronary artery disease (32% vs 13%) and a final diagnosis of a cardiac cause for their OHCA (89% vs 72%), both P = 0.01. Rates of coronary angiography (81% vs 71%, P = 0.23) and percutaneous coronary intervention (51% vs 42%, P = 0.37) were comparable among males and females. No differences in rates of in-hospital mortality (38% vs 37%, P = 0.90) and 30-day major adverse cardiac and cerebrovascular events (composite of all-cause mortality, myocardial infarction, coronary revascularization and nonfatal stroke) (39% vs 41%, P = 0.79) were observed between males and females, respectively. Female sex was not associated with worse in-hospital mortality when adjusted for other variables (odds ratio 0.66, 95% confidence interval 0.28-1.60, P = 0.36).

CONCLUSION

Among patients presenting with OHCA and a shockable rhythm, baseline sex and sex differences were not associated with disparities in short-term outcomes in contemporary systems of care.

The association between CPR quality of In-hospital resuscitation and sex: A hypothesis generating, prospective observational study

Introduction

The relationship between sex and cardiopulmonary resuscitation (CPR) outcomes remains unclear. Particularly, questions remain regarding the potential contribution of unmeasured confounders. We aimed to examine the differences in the quality of chest compression delivered to men and women.

Methods

Prospective study of observational data recorded during consecutive resuscitations occurring in a single tertiary center (Feb-1-2015 to Dec-31-2018) with real-time follow-up to hospital discharge. The studied variables included time in CPR, no-flow-time and fraction, compression rate and depth and release velocity. The primary study endpoint was the unadjusted association between patient sex and the chest compression quality (depth and rate). The secondary endpoint was the association between the various components of chest compression quality, sex, and survival to hospital discharge/neurologically intact survival.

Results

Overall 260 in-hospital resuscitations (57.7% male patients) were included. Among these 100 (38.5%) achieved return of spontaneous circulation (ROSC) and 35 (13.5%) survived to hospital discharge. Female patients were significantly older. Ischemic heart disease and ventricular arrhythmias were more prevalent among males. Compression depth was greater in female vs male patients (54.9 ± 11.3 vs 51.7 ± 10.9 mm; p = 0.024). Other CPR quality-metrics were similar. The rates of ROSC, survival to hospital discharge and neurologically intact survival did not differ between males and females. Univariate analysis revealed no association between sex, quality metrics and outcomes.

Discussion

Women received deeper chest compressions during in-hospital CPR. Our findings require corroboration in larger cohorts but nonetheless underscore the need to maintain high-quality CPR in all patients using real-time feedback devices. Future studies should also include data on ventilation rates and volumes which may contribute to survival outcomes.

Gender effect in survival after out-of-hospital cardiac arrest: A nationwide, population-based, case-control propensity score matched study based Korean national cardiac arrest registry

Objective

This study aimed to describe the relationship between sex and survival of patients with out-of-hospital cardiac arrest (OHCA) and further investigate the potential impact of female reproductive hormones on survival outcomes, by stratifying the patients into two age groups.

Methods

This retrospective, national population-based observational, case-control study, included Korean OHCA data from January 1, 2009, to December 31, 2016. We used multiple logistic regression with propensity score-matched data. The primary outcome was survival-to-discharge.

Results

Of the 94,160 patients with OHCA included, 34.2% were women. Before propensity score matching (PSM), the survival-to-discharge rate was 5.2% for females and 9.1% for males, in the entire group (OR 0.556, 95% CI [–0.526–0.588], P<0.001). In the reproductive age group (age 18–44 years), the survival-to-discharge rate was 14% for females and 15.6% for males (OR 0.879, 95% CI [0.765–1.012], P = 0,072) and in the post-menopause age group (age ≥ 55 years), the survival-to-discharge rate was 4.1% for females and 7% for males (OR 0.562, 95% CI [0.524–0.603], P<0.001). After PSM (28,577 patients of each sex), the survival-to-discharge rate was 5.4% for females and 5.4% for males (OR, 1.009 [0.938–1.085], P = 0.810). In the reproductive age group, the survival-to-discharge rate was 14.5% for females and 11.5% for males (OR 1.306, 95% CI [1.079–1.580], P = 0.006) and in the post-menopause age group, the survival-to-discharge rate was 4.2% for females and 4.6% for males (OR 0.904, 95% CI [0.828–0.986], P = 0.022). After adjustment for confounders, women of reproductive age were more likely to survive at hospital discharge. However, there was no statistically significant difference in neurological outcome (OR 1.238, 95% CI [0.979–1.566], P = 0.074).

Conclusions

Females of reproductive age had a better chance of survival when matched for confounding factors. Further studies using sex hormones are needed to improve the survival rate of patients with OHCA.

Postresuscitation care and prognostication after cardiac arrest-Does sex matter?

Background

There are conflicting results concerning sex-specific differences in the post-cardiac arrest period. We investigated the sex distribution of patients after successful cardiopulmonary resuscitation (CPR), differences in treatment, complications, outcome and sex-specific performance of biomarkers for prognostication of neurological outcome.

Methods

Prospective observational study including cardiac-arrest (CA) patients treated with mild therapeutic hypothermia (MTH) at 33 °C for 24 h or normothermia. We investigated common complications including pneumonia and acute kidney injury (AKI) and neuron-specific enolase, secretoneurin and tau protein as biomarkers of neurological outcome, which was assessed with the cerebral performance categories score at hospital discharge.

Results

Out of 134 patients 26% were female. Women were significantly older (73 years, interquartile range (IQR) 56–79 years vs. 62 years, IQR 53–70 years; p = 0.038), whereas men showed a significantly higher rate of pneumonia (29% vs. 6%; p = 0.004) and a trend towards higher rates of AKI (62% vs. 45%; p = 0.091). Frequency of MTH treatment was not significantly different (48% vs. 31%; p = 0.081). Female sex was not associated with neurological outcome in multivariable analysis (p = 0.524). There was no significant interaction of sex with prognostication of neurological outcome at 24, 48 and 72 h after CPR. At the respective time intervals p_interaction for neuron-specific enolase was 0.524, 0.221 and 0.519, for secretoneurin 0.893, 0.573 and 0.545 and for tau protein 0.270, 0.635, and 0.110.

Conclusion

The proportion of female patients was low. Women presented with higher age but had fewer complications during the post-CA period. Female sex was not associated with better neurological outcome. The performance of biomarkers is not affected by sex.

Supplementary Information

The online version of this article (10.1007/s00508-022-02026-x) contains supplementary material, which is available to authorized users.

Sex differences in post cardiac arrest discharge locations

Background

We explored sex-based differences in discharge location after resuscitation from cardiac arrest.

Methods

We performed a single-center retrospective cohort study including patients hospitalized after resuscitation from cardiac arrest from January 2010 to May 2020. We identified patients from a prospective registry, from which we extracted standard demographic and clinical variables. We explored favorable discharge location, defined as discharge to home or acute rehabilitation for survivors to hospital discharge. We tested the association of sex with the residuals of a multivariable logistic regression built using bidirectional selection to control for clinically relevant covariates.

Results

We included 2,278 patients. Mean age was 59 (SD 16), 40% were women, and 77% were admitted after out-of-hospital cardiac arrest. A total of 970 patients (43%) survived to discharge; of those, 607 (63% of survivors) had a favorable discharge location. Female sex showed a weak independent association with unfavorable discharge location (adjusted OR 0.94 (95%CI 0.89–0.99)).

Conclusions

Our results suggest a possible sex-based disparity in discharge location after cardiac arrest.

Gender difference in the clinical outcomes of patients with out-of-hospital cardiac arrest: A report using data from a national Korean registry

We explored gender differences in the characteristics and outcomes of patients with out-of-hospital cardiac arrest (OHCA) in Korea.We retrospectively analyzed a nationwide multicenter registry of out-of-hospital cardiac arrest patients that prospectively collected from January to December 2014, and explored the clinical outcomes of 670 successfully resuscitated adult patients with OHCA who were transferred to 27 hospitals. The effect of gender on the 30-day neurologically favorable survival (cerebral performance category 1 or 2) was analyzed after propensity score matching (PSM) of each patient in terms of clinical characteristics.We included 670 patients with OHCA, of whom 482 (72%) were male and 182 (28%) were female. The frequency of witnessed arrests and proportion of home arrests were similar between men and women (73.7% vs 71.3%, P = .59, and 55.0% vs 60.6% P = .21, respectively). Women were older than men (mean age, 65.9 vs 59.7 years, P < .001) and less likely to present with an initial shockable rhythm (27.7% vs 45.0%, P < .001). Women were less likely to undergo targeted temperature management (19.1% vs 35.9%, P < .001), coronary angiography (14.9% vs 36.1%, P < .001), or revascularization (7.4% vs 19.3%, P < .001). Compared with men, women exhibited poorer 30-day neurologically favorable survival (69.7% vs 83.0%, P = .001). However, the gender difference was not significant on PSM or inverse probability of treatment weighting (IPTW) analyses (P = .48 and P = .63, respectively).Female patients with OHCA exhibited poorer clinical characteristics and were less likely to receive treatment than men. After accounting for these differences, clinical outcomes did not differ by gender.

An Asian Perspective on Gender Differences in In-Hospital and Long-Term Outcome of Cardiac Mortality and Ischemic Stroke after Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction

OBJECTIVES

Gender differences historically exist in cardiovascular disease, with women experiencing higher rates of major adverse cardiovascular events. We investigated these trends in a contemporary Asian cohort, examining the impact of gender differences on cardiac mortality and ischemic stroke after primary percutaneous coronary intervention (PPCI) for ST elevation myocardial infarction (STEMI).

MATERIALS AND METHODS

We analysed 3971 consecutive patients who underwent primary PCI for STEMI retrospectively. The primary outcome was cardiac mortality and ischemic stroke in-hospital, at one year and on longer-term follow up (median follow up 3.62 years, interquartile range 1.03-6.03 years).

RESULTS

There were 580 (14.6%) female patients and 3391 (85.4%) male patients. Female patients were older and had higher prevalence of hypertension, diabetes, previous strokes, and chronic kidney disease. Cardiac mortality was higher in female patients during in-hospital (15.5% vs. 6.2%), 1-year (17.4% vs. 7.0%) and longer term follow up (19.9% vs. 8.1%, log-rank test: p < 0.001). Similarly, females had higher incidence of ischemic stroke at in-hospital (2.6% vs. 1.0%), 1-year (3.6% vs. 1.4%) and in the longer-term (6.7% vs. 3.1%) as well (log-rank test: p < 0.001). Female gender remained an independent predictor of in-hospital cardiac mortality (HR 1.395, 95%CI 1.061-1.833, p=0.017) and on longer-term follow-up (HR 1.932 95%CI 1.212-3.080, p=0.006) even after adjusting for confounders.

CONCLUSIONS

Females were at higher risk of in-hospital and long-term cardiac mortality and ischemic stroke after PPCI for STEMI. Future studies are warranted to investigate the role of aggressive management of cardiovascular risk factors and follow-up to improve outcomes in the females with STEMI.

Interaction between gender and post resuscitation interventions on neurological outcome in an asphyxial rat model of cardiac arrest

PURPOSE

Previous clinical studies have suggested an effect of gender on outcome after out-of-hospital cardiac arrest, but the results are conflicting and there is no uniform agreement regarding gender differences in survival and prognosis. The present study was aimed to investigate the interaction between gender and post resuscitation interventions on neurological outcome in an asphyxial rat model of cardiac arrest.

METHODS

Asphyxia was induced by blocking the endotracheal tube in 120 adult Sprague-Dawley rats (60 males and 60 females) at the same age. Cardiopulmonary resuscitation (CPR) was started after 5 min of untreated cardiac arrest. Animals were randomized into one of the three post resuscitation care intervention groups (n = 40, 20 males) immediately after resuscitation: (1) normothermic control (NC): ventilated with 2% N2/98% O2 for 1 h under normothermia; (2) targeted temperature management (TTM): ventilated with 2% N2/98% O2 for 1 h under hypothermia; (3) hydrogen inhalation (HI): ventilated with 2% H2/98% O2 for 1 h under normothermia. Physiological variables were recorded during the 5 h post resuscitation monitoring period. Neurological deficit score (NDS) and accumulative survival were used to assess 96 h outcomes. Mutual independence analysis and Mantel-Haenszel stratified analysis were used to explore the associations among gender, intervention and survival.

RESULTS

The body weights of female rats were significantly lighter than males, but CPR characteristics did not differ between genders. Compared with male rats, females had significantly lower mean arterial pressure, longer onset time of the electroencephalogram (EEG) burst and time to normal EEG trace (TTNT) in the NC group; relatively longer TTNT in the TTM group; and substantially longer TTNT, lower NDSs, and higher survival in the HI group. Mutual independence analysis revealed that both gender and intervention were associated with neurological outcome. Mantel-Haenszel stratified analysis demonstrated that female rats had significantly higher survival rate than males when adjusted for the confounder intervention.

CONCLUSION

In this rat model cardiac arrest and CPR, gender did not affect resuscitation but associated with neurological outcome. The superiority of female rats in neurological recovery was affected by post resuscitation interventions and female rats were more likely to benefit from hydrogen therapy.

Sex Disparities in Sudden Cardiac Death

The overall incidence of sudden cardiac death is considerably lower among women than men, reflecting significant and often under-recognized sex differences. Women are older at time of sudden cardiac death, less likely to have a prior cardiac diagnosis, and less likely to have coronary artery disease identified on postmortem examination. They are more likely to experience their death at home, during sleep, and less likely witnessed. Women are also more likely to present in pulseless electrical activity or systole rather than ventricular fibrillation or ventricular tachycardia. Conversely, women are less likely to receive bystander cardiopulmonary resuscitation or receive cardiac intervention post-arrest. Underpinning sex disparities in sudden cardiac death is a paucity of women recruited to clinical trials, coupled with an overall lack of prespecified sex-disaggregated evidence. Thus, predominantly male-derived data form the basis of clinical guidelines. This review outlines the critical sex differences concerning epidemiology, cause, risk factors, prevention, and outcomes. We propose 4 broad areas of importance to consider: physiological, personal, community, and professional factors.

Influence of sex on survival, neurologic outcomes, and neurodiagnostic testing after out-of-hospital cardiac arrest

AIM

Previous studies evaluating the relationship between sex and post-resuscitation care and outcomes following out-of-hospital cardiac arrest (OHCA) are conflicting. We investigated the association between sex and outcomes as well as neurodiagnostic testing in a prospective multicenter international registry of patients admitted to intensive care units following OHCA.

METHODS

OHCA survivors enrolled in the International Cardiac Arrest Registry (INTCAR) from 2012-2017 were included. We assessed the independent association between sex and survival to hospital discharge, good neurologic outcome (Cerebral Performance Category 1 or 2), neurodiagnostic testing, and withdrawal of life-sustaining therapy (WLST).

RESULTS

Of 2,407 eligible patients, 809 (33.6%) were women. Baseline characteristics differed by sex, with less bystander CPR and initial shockable rhythms among women. Women were less likely to survive to hospital discharge, however significance abated following adjusted analysis (30.1% vs 42.7%, adjusted OR 0.85, 95% CI 0.67-1.08). Women were less likely to have good neurologic outcome at discharge (21.4% vs 34.0%, adjusted OR 0.74, 95% CI 0.57-0.96) and at six months post-arrest (16.7% vs 29.4%, adjusted OR 0.73, 95% CI 0.54-0.98) that persisted after adjustment. Neuroimaging (75.5% vs 74.3%, p=0.54) and other neurophysiologic testing (78.8% vs 78.6%, p=0.91) was similar across sex. Women were more likely to undergo WLST (55.6% vs 42.8%, adjusted OR 1.35, 95% CI 1.09-1.66).

CONCLUSIONS

Women with cardiac arrest have lower odds of good neurologic outcomes and higher odds of WLST, despite comparable rates of neurodiagnostic testing and after controlling for baseline differences in clinical characteristics and cardiac arrest features.

Sex differences in acute cardiovascular care: a review and needs assessment

Despite significant progress in the care of patients suffering from cardiovascular disease, there remains a persistent sex disparity in the diagnosis, management, and outcomes of these patients. These sex disparities are seen across the spectrum of cardiovascular care, but, are especially pronounced in acute cardiovascular care. The spectrum of acute cardiovascular care encompasses critically ill or tenuous patients with cardiovascular conditions that require urgent or emergent decision-making and interventions. In this narrative review, the disparities in the clinical course, management, and outcomes of six commonly encountered acute cardiovascular conditions, some with a known sex-predilection will be discussed within the basis of underlying sex differences in physiology, anatomy, and pharmacology with the goal of identifying areas where improvement in clinical approaches are needed.

Women have lower chances than men to be resuscitated and survive out-of-hospital cardiac arrest

Aims

Previous studies on sex differences in out-of-hospital cardiac arrest (OHCA) had limited scope and yielded conflicting results. We aimed to provide a comprehensive overall view on sex differences in care utilization, and outcome of OHCA.

Methods and results

We performed a population-based cohort-study, analysing all emergency medical service (EMS) treated resuscitation attempts in one province of the Netherlands (2006–2012). We calculated odds ratios (ORs) for the association of sex and chance of a resuscitation attempt by EMS, shockable initial rhythm (SIR), and in-hospital treatment using logistic regression analysis. Additionally, we provided an overview of sex differences in overall survival and survival at successive stages of care, in the entire study population and in patients with SIR. We identified 5717 EMS-treated OHCAs (28.0% female). Women with OHCA were less likely than men to receive a resuscitation attempt by a bystander (67.9% vs. 72.7%; P < 0.001), even when OHCA was witnessed (69.2% vs. 73.9%; P < 0.001). Women who were resuscitated had lower odds than men for overall survival to hospital discharge [OR 0.57; 95% confidence interval (CI) 0.48–0.67; 12.5% vs. 20.1%; P < 0.001], survival from OHCA to hospital admission (OR 0.88; 95% CI 0.78–0.99; 33.6% vs. 36.6%; P = 0.033), and survival from hospital admission to discharge (OR 0.49, 95% CI 0.40–0.60; 33.1% vs. 51.7%). This was explained by a lower rate of SIR in women (33.7% vs. 52.7%; P < 0.001). After adjustment for resuscitation parameters, female sex remained independently associated with lower SIR rate.

Conclusion

In case of OHCA, women are less often resuscitated by bystanders than men. When resuscitation is attempted, women have lower survival rates at each successive stage of care. These sex gaps are likely explained by lower rate of SIR in women, which can only partly be explained by resuscitation characteristics.

Sex differences in survival after out-of-hospital cardiac arrest: a meta-analysis

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a leading cause of sudden cardiac death worldwide. Researchers have found significant pathophysiological differences between females and males and clinically significant sex differences related to medical services. However, conflicting results exist and there is no uniform agreement regarding sex differences in survival and prognosis after OHCA. Therefore, we investigated the relationship between the prognosis of OHCA and sex factors.

METHODS

We comprehensively searched the PubMed, Embase, and Cochrane databases and obtained a total of 1042 articles, from which 33 studies were selected for inclusion. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using a random-effects model.

RESULTS

The meta-analysis included 1,268,664 patients. Compared with males, females were older (69.7 years vs. 65.4 years, p < 0.05) and more frequently suffered OHCA without witnesses (58.39% vs 62.70%, p < 0.05). Females were less likely to receive in-hospital interventions than males. There was no significant difference between females and males in the survival from OHCA to hospital admission (OR 0.99, 95% CI 0.89-1.1). However, females had lower chances for survival from hospital admission to discharge (OR 0.59, 95% CI 0.48-0.73), overall survival to hospital discharge (OR 0.73, 95% CI 0.62-0.86), and favorable neurological outcomes (OR 0.62, 95% CI 0.47-0.83) compared with males.

CONCLUSIONS

Our results indicate that the overall discharge survival rate of females is lower than that of males, and females face a poor prognosis of the nervous system. This is likely related to the pathophysiological characteristics of females, more conservative treatment measures compared with males, and different post-resuscitation care. However, these findings should be interpreted with caution due to the presence of several confounding factors.

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.

Association of Bystander and First-Responder Efforts and Outcomes According to Sex: Results From the North Carolina HeartRescue Statewide Quality Improvement Initiative

Background

The Institute of Medicine has called for actions to understand and target sex‐related differences in care and outcomes for out‐of‐hospital cardiac arrest patients. We assessed changes in bystander and first‐responder interventions and outcomes for males versus females after statewide efforts to improve cardiac arrest care.

Methods and Results

We identified out‐of‐hospital cardiac arrests from North Carolina (2010–2014) through the CARES (Cardiac Arrest Registry to Enhance Survival) registry. Outcomes for men versus women were examined through multivariable logistic regression analyses adjusted for (1) nonmodifiable factors (age, witnessed status, and initial heart rhythm) and (2) nonmodifiable plus modifiable factors (bystander cardiopulmonary resuscitation and defibrillation before emergency medical services), including interactions between sex and time (ie, year and year²). Of 8100 patients, 38.1% were women. From 2010 to 2014, there was an increase in bystander cardiopulmonary resuscitation (men, 40.5%–50.6%; women, 35.3%–51.8%; P for each <0.0001) and in the combination of bystander cardiopulmonary resuscitation and first‐responder defibrillation (men, 15.8%–23.0%, P=0.007; women, 8.5%–23.7%, P=0.004). From 2010 to 2014, the unadjusted predicted probability of favorable neurologic outcome was higher and increased more for men (men, from 6.5% [95% confidence interval (CI), 5.1–8.0] to 9.7% [95% CI, 8.1–11.3]; women, from 6.3% [95% CI, 4.4–8.3] to 7.4% [95% CI, 5.5–9.3%]); while adjusted for nonmodifiable factors, it was slightly higher but with a nonsignificant increase for women (from 9.2% [95% CI, 6.8–11.8] to 10.2% [95% CI, 8.0–12.5]; men, from 5.8% [95% CI, 4.6–7.0] to 8.4% [95% CI, 7.1–9.7]). Adding bystander cardiopulmonary resuscitation and defibrillation before EMS (modifiable factors) did not substantially change the results.

Conclusions

Bystander and first‐responder interventions increased for men and women, but outcomes improved significantly only for men. Additional strategies may be necessary to improve survival among female cardiac arrest patients.

Gender differences in cognitive outcome after cardiac arrest: A retrospective cohort study

Introduction: Recent studies have suggested gender disparities in neurologic outcome after cardiac arrest (CA). However, the relation between gender and cognitive outcome has been rarely examined. Here we investigated whether sex is associated with cognitive outcome after CA events.Methods: A retrospective analysis was conducted using data collected at our institution from January 2006 to May 2017. Patients were included if they had a documented CA and were able to participate in structured neuropsychological testing. Cognitive status was assessed at about 2.1 month after CA and included tests of attention as well as short and long-term memory. Gender was used as the main predictor of outcome and was studied in relation to age, depressive mood, therapeutic hypothermia (TH), and other potential confounders.Results: Males were more likely to show favorable cognitive outcome in both univariate and multivariate analyses. Women were more likely to exhibit depressive mood. Patients who underwent TH (31% of the patients) did not show any gender differences in benefits from the treatment. Among males and females, no significant differences between age groups could be observed.Conclusions: Male sex was associated with favorable cognitive outcome after CA which could not be attributed to baseline characteristics.

Gender differences in the provision of key post-arrest interventions for out-of-hospital cardiac arrest (OHCA) patients-protocol for a systematic review

BACKGROUND

Evidence shows that the implementation of optimal post-arrest care significantly increases survival and functional outcomes among patients who experience an out-of-hospital cardiac arrest (OHCA). However, differences in OHCA survival have been reported between men and women, suggesting underlying differences in post-arrest care. This systematic review will evaluate gender differences in the provision of key post-arrest interventions.

METHODS

Eligible studies will be identified through systematic searches of relevant databases. Randomized controlled trials and observational studies of adult patients will be eligible for inclusion if they report gender-specific data on the provision of one or more guideline-based post-arrest interventions in OHCA patients who survived to hospital admission. Two independent reviewers will perform both the title and abstract and full-text screening along with data abstraction for the selected studies. Study quality will be assessed using a modified Cochrane Risk of Bias tool for RCTs or the ROBINS-I tool for observational studies. The strength of evidence for each included study will be assessed using a modified Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system.

DISCUSSION

To our knowledge, this systematic review will be the first to address the association between patient gender and the provision of post-arrest care. The findings from this systematic review will provide valuable insight to gender disparities in the provision of post-arrest care. This systematic review was designed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This protocol observes the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) statement.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42012003096.

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.

Frequency and influencing factors of cardiopulmonary resuscitation-related injuries during implementation of the American Heart Association 2010 Guidelines: a retrospective study based on autopsy and postmortem computed tomography

AIM

To determine the frequency of cardiopulmonary resuscitation (CPR)-related injuries and factors involved in their occurrence, data based on forensic autopsy and postmortem computed tomography (PMCT) during implementation of the 2010 American Heart Association Guidelines for CPR were studied.

METHODS

We retrospectively evaluated data on adult patients with non-traumatic deaths who had undergone manual CPR and autopsy from January 2012 to December 2014. CPR-related injuries were analyzed on autopsy records and PMCT images and compared with results of previous studies.

RESULTS

In total, 180 consecutive cases were analyzed. Rib fractures and sternal fractures were most frequent (overall frequency, 66.1 and 52.8%, respectively), followed by heart injuries (12.8%) and abdominal visceral injuries (2.2%). Urgently life-threatening injuries were rare (2.8%). Older age was an independent risk factor for rib fracture [adjusted odds ratio (AOR), 1.06; 95% confidence interval (CI), 1.04-1.08; p < 0.001], ≥ 3 rib fractures (AOR, 1.06; 95% CI, 1.02-1.09; p = 0.002), and sternal fracture (AOR, 1.03; 95% CI, 1.01-1.05; p < 0.001). Female sex was significantly associated with sternal fracture (AOR, 2.08; 95% CI, 1.02-4.25; p = 0.04). Chest compression only by laypersons was inversely associated with rib and sternal fractures. Body mass index and in-hospital cardiac arrest were not significantly associated with any complications. The frequency of thoracic skeletal injuries was similar to that in recent autopsy-based studies.

CONCLUSIONS

Implementation of the 2010 Guidelines had little impact on the frequency of CPR-related thoracic skeletal injuries or urgently life-threatening complications. Older age was the only independent factor related to thoracic skeletal injuries.

Women have a worse prognosis and undergo fewer coronary angiographies after out-of-hospital cardiac arrest than men

Background:

Out-of-hospital cardiac arrest is more often reported in men than in women.

Objectives:

We aimed to assess sex-related differences in post-resuscitation care; especially with regards to coronary angiography, percutaneous coronary intervention, mortality and functional status after out-of-hospital cardiac arrest.

Methods:

We included 704 consecutive adult out-of-hospital cardiac arrest-patients with cardiac aetiology in the Copenhagen area from 2007–2011. Utstein guidelines were used for the pre-hospital data. Vital status and pre-arrest comorbidities were acquired from Danish registries and review of patient charts. Logistic regression was used to assess differences in functional status and use of post-resuscitation care. Cox regression was used to assess differences in 30-day mortality. We used ‘smcfcs’ and ‘mice’ imputation to handle missing data.

Results:

Female sex was associated with higher 30-day mortality after adjusting for age and comorbidity (hazard ratio (HR): 1.42, confidence interval (CI): 1.13–1.79, p<0.01), this was not significant when adjusting for primary rhythm (HR: 1.12, CI: 0.88–1.42, p=0.37). Women less frequently received coronary angiography <24 h in multiple regression after out-of-hospital cardiac arrest (odds ratio (OR)CAG=0.55, CI: 0.31–0.97, p=0.041), however no difference in percutaneous coronary intervention was found (ORPCI=0.55, CI: 0.23–1.36, p=0.19). Coronary artery bypass grafting was less often performed in women (ORCABG: 0.10, CI: 0.01–0.78, p=0.03). There was no difference in functional status at discharge between men and women ( p=1).

Conclusion:

Female sex was not significantly associated with higher mortality when adjusting for confounders. Women less often underwent coronary angiography and coronary artery bypass grafting, but it is not clear whether this difference can be explained by other factors, or an actual under-treatment in women.

Investigation of complications secondary to chest compressions before and after the 2010 cardiopulmonary resuscitation guideline changes by using multi-detector computed tomography: a retrospective study

Background

The purpose of this study was to identify the relationship between the deeper and faster chest compressions suggested by the 2010 cardiopulmonary resuscitation guidelines and complications arising from chest compressions, using multi-detector computed tomography.

Methods

We performed a retrospective analysis of prospective registry data. This study was conducted with in- and out-of-hospital cardiac arrest patients who underwent successful resuscitation in the emergency departments of two academic tertiary care centres from October 2006 to September 2010 (pre-2010 group) and from October 2011 to September 2015 (post-2010 group). We examined chest injuries related to chest compressions, classified as follows: rib fracture, sternal fracture, and other uncommon complications.

Results

We enrolled 185 patients in this study. The most frequent complication to occur in both groups was rib fracture: 27 (62.8%) and 112 (78.9%) patients in the pre-2010 and post-2010 groups, respectively (p = 0.03). However, we observed no statistical differences in sternum fracture, the second most common complication (p = 0.80). Retrosternal and mediastinal haematoma were not reported in the pre-2010 group but 13 patients (9.1%) in the post-2010 group were reported to have haematoma (p = 0.04). Nine serious, life-threatening complications occurred, all in the post-2010 group. Among the younger group (less than 65 years old), 8 (38.1%) patients in the pre-2010 group and 40 (64.5%) in the post-2010 group sustained rib fractures.

Discussion

The deeper and faster chest compressions for enhancing ROSC are associated with increased occurrence of complications. Additional studies are needed to compensate for the limitations of our study design.

Conclusions

This study found that the 2010 guidelines, recommending deeper and faster chest compressions, led to an increased proportion of rib fractures and retrosternal and mediastinal haematoma.

[Sudden cardiac death: Are women different?]

Sudden cardiac death is a major public health problem with around 40,000 cases per year in France. Epidemiological, clinical and prognostic differences according to gender have been described in most cardiovascular diseases, including sudden cardiac death. In this article, we will review gender differences in sudden cardiac death incidence, circumstance of occurrence, management, and prognosis.

Sex Differences in Survival From Out-of-Hospital Cardiac Arrest in the Era of Regionalized Systems and Advanced Post-Resuscitation Care

BACKGROUND

The purpose of this study was to evaluate sex differences in out-of-hospital cardiac arrest (OHCA) characteristics, interventions, and outcomes.

METHODS AND RESULTS

This is a retrospective analysis from a regionalized cardiac arrest system. Data on patients treated for OHCA are reported to a single registry, from which all adult patients were identified from 2011 through 2014. Characteristics, treatment, and outcomes were evaluated with stratification by sex. The adjusted odds ratio (OR) for survival with good neurological outcome (cerebral performance category 1 or 2) was calculated for women compared to men. There were 5174 out-of-hospital cardiac arrests (OHCAs; 3080 males and 2094 females). Women were older, median 71 (interquartile range [IQR], 59-82) versus 66 years (IQR, 55-78). Despite similar frequency of witnessed arrest, women were less likely to present with a shockable rhythm (22% vs 35%; risk difference [RD], 13%; 95% CI, 11-15), have ST-segment elevation myocardial infarction (23% vs 32%; RD, 13%; 95% CI, 7-11), or receive coronary angiography (11% vs 25%; RD, 14%; 95% CI, 12-16), percutaneous coronary intervention (5% vs 14%; RD, 9%; 95% CI, 7-11), or targeted temperature management (33% vs 40%; RD, 7%; 95% CI, 4-10). Women had decreased survival to discharge (33% vs 40%; RD, 7%; 95% CI, 4-10) and a lower proportion of good neurological outcome (16% vs 24%; RD, 8%; 95% CI, 6-10). In multivariable modeling, female sex was not associated with decreased survival with good neurological outcome (OR, 0.9; 95% CI, 0.8-1.1).

CONCLUSIONS

Sex-related differences in OHCA characteristics and treatment are predictors of survival outcome disparities. With adjustment for these factors, sex was not associated with survival or neurological outcome after OHCA.

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.

Effect of gender on outcome of out of hospital cardiac arrest in the Resuscitation Outcomes Consortium

INTRODUCTION

This study examined the relationship between gender and outcomes of non-traumatic out-of-hospital cardiac arrest (OHCA).

METHODS

All eligible, consecutive, non-traumatic Emergency Medical Services (EMS) treated OHCA patients in the Resuscitation Outcomes Consortium between December 2005 and May 2007. Patient age was analyzed as a continuous variable and stratified in two age cohorts: 15-45 and >55 years of age (yoa). Unadjusted and adjusted (based on Utstein characteristics) chi square tests and logistic regression models were employed to examine the relationship between gender, age, and survival outcomes.

RESULTS

This study enrolled 14,690 patients: of which 36.4% were women with a mean age of 68.3 and 63.6% of them men with a mean age of 64.2. Women survived to hospital discharge less often than men (6.4% vs. 9.1%, p<0.001); the unadjusted OR was 0.69, 95%CI: 0.60, 0.77 whereas when adjusted for all Utstein predictors the difference was not significant (OR: 1.16, 95%CI: 0.98, 1.36, p=0.07). The adjusted survival rate for younger women (15-45 yoa) was 11.1% vs. 9.8% for younger men (OR: 1.66, 95%CI: 1.04, 2.64, p=0.03) but no difference in discharge rates was observed in the >55 cohort (OR: 0.94, 95%CI: 0.78, 1.15, p=0.57).

CONCLUSIONS

Women who suffer OHCAs have lower rates of survival and have unfavourable Utstein predictors. When survival is adjusted for these predictors survival is similar between men and women except in younger women suggesting that age modifies the association of gender and survival from OHCA; a result that supports a protective hormonal effect among premenopausal women.

Association of gender to outcome after out-of-hospital cardiac arrest--a report from the International Cardiac Arrest Registry

Introduction

Previous studies have suggested an effect of gender on outcome after out-of-hospital cardiac arrest (OHCA), but the results are conflicting. We aimed to investigate the association of gender to outcome, coronary angiography (CAG) and adverse events in OHCA survivors treated with mild induced hypothermia (MIH).

Methods

We performed a retrospective analysis of prospectively collected data from the International Cardiac Arrest Registry. Adult patients with a non-traumatic OHCA and treated with MIH were included. Good neurological outcome was defined as a cerebral performance category (CPC) of 1 or 2.

Results

A total of 1,667 patients, 472 women (28%) and 1,195 men (72%), met the inclusion criteria. Men were more likely to receive bystander cardiopulmonary resuscitation, have an initial shockable rhythm and to have a presumed cardiac cause of arrest. At hospital discharge, men had a higher survival rate (52% vs. 38%, P <0.001) and more often a good neurological outcome (43% vs. 32%, P <0.001) in the univariate analysis. When adjusting for baseline characteristics, male gender was associated with improved survival (OR 1.34, 95% CI 1.01 to 1.78) but no longer with neurological outcome (OR 1.24, 95% CI 0.92 to 1.67). Adverse events were common; women more often had hypokalemia, hypomagnesemia and bleeding requiring transfusion, while men had more pneumonia. In a subgroup analysis of patients with a presumed cardiac cause of arrest (n = 1,361), men more often had CAG performed on admission (58% vs. 50%, P = 0.02) but this discrepancy disappeared in an adjusted analysis.

Conclusions

Gender differences exist regarding cause of arrest, adverse events and outcome. Male gender was independently associated with survival but not with neurological outcome.

Computed tomography findings of complications resulting from cardiopulmonary resuscitation

INTRODUCTION

This retrospective study was conducted to evaluate injuries related to cardiopulmonary resuscitation (CPR) and their associated factors using postmortem computed tomography (PMCT) and whole body CT after successful resuscitation.

METHODS

The inclusion criteria were adult, non-traumatic, out-of-hospital cardiac arrest patients who were transported to our emergency room between April 1, 2008 and March 31, 2013. Following CPR, PMCT was performed in patients who died without return of spontaneous circulation (ROSC). Similarly, CT scans were performed in patients who were successfully resuscitated within 72h after ROSC. The injuries associated with CPR were analysed retrospectively on CT images.

RESULTS

During the study period, 309 patients who suffered out-of hospital cardiac arrest were transported to our emergency room and received CPR; 223 were enrolled in the study. The CT images showed that 156 patients (70.0%) had rib fractures, and 18 patients (8.1%) had sternal fractures. Rib fractures were associated with older age (78.0 years vs. 66.0 years, p<0.01), longer duration of CPR (41min vs. 33min, p<0.01), and lower rate of ROSC (26.3% vs. 55.3%, p<0.01). All sternal fractures occurred with rib fractures and were associated with a greater number of rib fractures, higher age, and a lower rate of ROSC than rib fractures only cases. Bilateral pneumothorax was observed in two patients with rib fractures.

CONCLUSIONS

PMCT is useful for evaluating complications related to chest compression. Further investigations with PMCT are needed to reduce complications and improve the quality of CPR.

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

BACKGROUND

The effect of sex on survival in out-of-hospital cardiac arrest (OHCA) is controversial. Some studies report more favorable outcomes in women, while others suggest the opposite, citing disparities in care. Whether sex predicts differential age-specific survival is still uncertain.

OBJECTIVES

The objective was to study the sex-associated variation in survival to hospital discharge in OHCA patients as well as the relationship between age and sex for predicting survival.

METHODS

The Ontario Prehospital Advanced Life Support (OPALS) registry, collected in a large study of rapid defibrillation and advanced life support programs, is Utstein-compliant and has data on OHCA patients (1994 to 2002) from 20 communities in Ontario, Canada. All adult OHCAs not witnessed by emergency medical services (EMS) and treated during one of the three main OPALS phases were included. Clinically significant variables were chosen a priori (age, sex, witnessed arrest, initial cardiopulmonary resuscitation [CPR], shockable rhythm, EMS response interval, and OPALS study phase) and entered into a multivariable logistic regression model with survival to hospital discharge as the outcome, with sex and age as the primary risk factors. Fractional polynomials were used to explore the relationship between age and survival by sex.

RESULTS

A total of 11,479 (out of 20,695) OPALS cases met inclusion criteria and 10,862 (94.6%) had complete data for regression analysis. As a group, women were older than men (median age = 74 years vs. 69 years, p < 0.01), had fewer witnessed arrests (43% vs. 49%; p < 0.01), had fewer initial ventricular fibrillation/ventricular tachycardia rhythms (24% vs. 42%; p < 0.01), had a lower rate of bystander CPR (12% vs. 17%; p < 0.01), and had lower survival (1.7% vs. 3.2%; p < 0.01). Survival to hospital admission and return of spontaneous circulation did not differ between women and men (p > 0.05). The relationship between age, sex, and survival to hospital discharge could not be analyzed in a single regression model, as age did not have a linear relationship with survival for men, but did for women. Thus, age was kept as a continuous variable for women but was transformed for men using fractional polynomials [ln(age) + age(3) ]. In sex-stratified regression models, the adjusted probability of survival for women decreased as age increased (adjusted odds ratio = 0.88, 95% confidence interval = 0.81 to 0.96, per 5-year increase in age) while for men, the probability of survival initially increased with age until age 65 years and then decreased with increasing age. Women had a higher probability of survival until age 47 years, after which men maintained a higher probability of survival.

CONCLUSIONS

Overall OHCA survival for women was lower than for men in the OPALS study. Factors related to the sex differences in survival (rates of bystander CPR and shockable rhythms) may be modifiable. The probability of survival differed across age for men and women in a nonlinear fashion. This differential influence of age on survival for men and women should be considered in future studies evaluating survival by sex in OHCA population.

The influence of female gender on cardiac arrest outcomes: a systematic review of the literature

BACKGROUND

Sudden cardiac arrest is an important cause of cardiovascular mortality. The impact of gender on the outcome of cardiac arrest is not clear and data about that is limited.

OBJECTIVE

Understanding the influence of gender on cardiac arrest through a systematic review of the published literature.

METHODS

A search of all published studies in English between January 1970 and May 2013 was performed using the electronic databases PubMed and MEDLINE, using the key words 'cardiac arrest', 'outcome', and 'gender'.

RESULTS

Eleven studies were included in this review, all of which were observational studies conducted using national-based database registries of cardiac arrest. A total of 548,440 patients were enrolled in these studies with 220,646 (40.3%) of them being female patients. In general, there was a lower percentage of women in the reported studies compared to men. Women were older in age and more likely to have non-shockable rhythms as the initial rhythm. Women also had a lower rate of witnessed arrest, a lower rate of bystander resuscitation, a higher rate of survival until hospital admission and a lower rate of in-hospital survival compared to men. Women also had a more favorable one month survival and neurological outcome.

CONCLUSION

In the reported literature female gender seems to offer survival and outcome advantages following out-of-hospital cardiac arrest over male gender. This is in contrast to most other aspects of heart disease in which women tend to have a worse prognosis.

Females of childbearing age have a survival benefit after out-of-hospital cardiac arrest

BACKGROUND

There is controversy regarding the association between age and being female and survival to hospital discharge after out-of-hospital cardiac arrest (OHCA). We hypothesized that younger females (aged 12-49 years) would be independently associated with increased survival after OHCA when compared to other age and sex groups.

METHODS

We conducted a secondary analysis of prospectively collected data from 29 United States cities that participate in the Cardiac Arrest Registry to Enhance Survival (CARES). Patients were included if they were ≥12 years of age and had a documented resuscitation attempt from October 1, 2005 through December 31, 2009. Hierarchical multivariable logistic regression analyses were used to estimate the associations between age and sex groups and survival to hospital discharge.

RESULTS

Females were less likely to have a cardiac arrest in public, was witnessed, or was treatable with defibrillation. Females in the 12-49 year old age group had a similar proportion of survival to hospital discharge when compared to age-matched males (females 11.6% vs. males 11.2%), while males ≥50 years old were more likely to survive when compared to age matched females (females 6.9% vs. males 9.6%). Age stratified regression models demonstrated that 12-49 year old females had the largest association with survival to hospital discharge (OR 1.55, 95% CI 1.20-2.00), while females in the ≥50 year old age group had a smaller increased odds of survival to hospital discharge (OR 1.18, 95% CI 1.03-1.35), which only lasted until the age of 55 years (OR 1.12, 95% CI 0.97-1.29).

CONCLUSIONS

Younger aged females were associated with increased odds of survival despite being found with poorer prognostic arrest characteristics.

Female sex is not associated with improved rates of ROSC or short term survival following prolonged porcine ventricular fibrillation

OBJECTIVES

There may be a survival benefit in female patients experiencing cardiac arrest, which could affect the interpretation of in vivo animal studies. We hypothesized that sex predicts return of spontaneous circulation (ROSC) and short-term survival (SURV) in porcine studies of prolonged ventricular fibrillation (VF).

METHODS

Retrospective analysis of eight comparable experiments performed in our lab using mixed-breed domestic swine of either sex. All experiments included prolonged untreated VF, CPR, defibrillation, and drugs. We defined ROSC as systolic blood pressure ≥80 mm Hg for ≥1 min. Short-term survival was defined 20 or 60 min, depending on protocol. Categorical variables were compared with chi-square test and Fisher's exact test. Continuous variables were compared with two-sample t-test and one-way ANOVA. Multiple logistic regression determined predictors of ROSC and SURV, utilizing cluster analysis by experimental protocol. Candidate variables were sex, weight, anesthesia duration, VF duration, and CPR ratio.

RESULTS

Of 263 swine analyzed (53.2% male), 58.6% of males and 68.3% of females had ROSC (p=0.10), whereas 50.0% of males and 61.0% of females experienced SURV (p=0.07).

RESULTS

Of 263 swine analyzed (53.2% male), 58.6% of males and 68.3% of females had ROSC (p=0.10), whereas 50.0% of males and 61.0% of females experienced SURV (p=0.07). Neither sex nor any identified candidate variable predicted ROSC or SURV. Both models had acceptable fit with Hosmer-Lemeshow values of 0.35 and 0.31, respectively.

CONCLUSIONS

Sex predicts neither ROSC nor SURV in a swine model of prolonged VF.

Chest injury following cardiopulmonary resuscitation: a prospective computed tomography evaluation

INTRODUCTION

Traumatic chest injuries may occur following cardiopulmonary resuscitation (CPR). The aim of this study was to address the frequency of injuries, especially rib and sternal fractures, and also to identify factors that contribute to post-CPR trauma.

METHODS

This study was a prospective cross-sectional study conducted in the emergency departments (ED) of eight academic tertiary care centers. To evaluate injuries secondary to CPR, we performed chest computed tomography (CT) in patients who were successfully resuscitated from cardiac arrest. Contributing factors that might be related to injuries were also investigated.

RESULTS

We enrolled 71 patients between 1 January 2011 and 30 June 2011. Rib and sternal fractures were diagnosed in 22 and 3 patients, respectively. Females were more susceptible to rib fracture (p=0.036). When non-physicians participated as chest compressors in the ED, more ribs were fractured (p=0.048). The duration of CPR and number of compressors were not contributing factors to trauma secondary to CPR. There was a wide variation in the frequency of rib fractures from hospital to hospital (0-83.3%). In high-risk hospitals (in which more than 50% of patients had rib fractures), the average age of the patients was higher, and non-physicians took part in ED CPR more often than they did at low-risk hospitals.

CONCLUSION

The incidence of rib fracture following CPR was different in various hospitals. The presence of non-physician chest compressors in the ED was one of the contributing factors to rib fracture. Further studies on the influence of resuscitators and relation between quality of chest compression and CPR-induced injuries are warranted to reduce complications following CPR.

Survival advantage from ventricular fibrillation and pulseless electrical activity in women compared to men: the Oregon Sudden Unexpected Death Study

OBJECTIVE

Studies evaluating a possible survival advantage from sudden cardiac arrest (SCA) in women have produced mixed results possibly due to a lack of comprehensive analyses. We hypothesized that race, socioeconomic status (SES), and elements of the lifetime clinical history influence gender effects and need to be incorporated within analyses of survival.

METHODS

Cases of SCA were identified from the ongoing, prospective, multiple-source Oregon Sudden Unexpected Death Study (population approximately one million). Subjects included were age ≥18 years who underwent attempted resuscitation by EMS providers. Pearson's chi-square tests and independent samples t tests or analysis of variance were used for univariate comparisons. We evaluated gender and race differences in survival adjusted for age, circumstances of arrest, disease burden, and socioeconomic status using a logistic regression model predicting survival.

RESULTS

A total of 1,296 cases had resuscitation attempted (2002-2007; mean age 65 years, male 67%). Women were older than men (68 vs. 63 years, p < 0.0001) and were more likely to have return of spontaneous circulation (41% vs. 33%, p = 0.004). Women were more likely to present with pulseless electrical activity (PEA) and asystole (p < 0.0001), and overall, PEA was more common among African Americans (p = 0.04). Higher survival to hospital discharge was observed in women compared to men presenting with ventricular fibrillation/tachycardia (34% vs. 24%, p = 0.02) or with PEA (10% vs. 3%, p = 0.007). In a multivariate model adjusting for age, race, presenting arrhythmia, arrest circumstances, arrest location, disease burden, and SES, women were more likely than men to survive to hospital discharge [odds ratio 1.85; 95% confidence interval (1.12-3.04)].

CONCLUSIONS

Despite older age, higher prevalence of SCA in the home, and higher rates of PEA, women had a survival advantage from ventricular fibrillation and pulseless electrical activity.

The effects of sex on out-of-hospital cardiac arrest outcomes

OBJECTIVE

We examined the effects of sex on out-of-hospital cardiac arrest outcomes. There is evidence that women are more likely to survive cardiac arrest than men. However, few large studies have examined these sex differences in detail. It is unknown whether the female survival advantage is age-specific or whether sex affects neurologic outcomes after cardiac arrest events.

METHODS

Data were analyzed from a nationwide population-based out-of-hospital cardiac arrest database (between January 2005 and December 2007) involving 318,123 patients (male: 188,357, female: 129,766) to assess the effects of sex on out-of-hospital cardiac arrest outcomes in Japan. We selected 276,590 patients aged 20 to 89 years with out-of-hospital cardiac arrest and compared the frequencies of initial cardiac rhythms, 1-month survival rates, and favorable neurologic outcome rates between sexes.

RESULTS

The incidence of out-of-hospital cardiac arrest was higher in men than in women (men: 0.12%; women: 0.07%). Men were witnessed more often while out-of-hospital cardiac arrest was occurring (men: 42.1% and women: 36.9%), typically presented with initial ventricular fibrillation/ventricular tachycardia rhythms, and had a higher 1-month survival rate overall after out-of-hospital cardiac arrest events (men: 5.2% and women: 4.3%). However, the rate of survival with a favorable neurologic outcome for women aged 30 to 49 years was significantly higher than that for men within the same age range. Among patients initially presenting with ventricular fibrillation/ventricular tachycardia, the rate of survival with favorable neurologic outcome was higher for women than men in the group aged 40 to 59 years.

CONCLUSION

Our results suggest that men have a higher 1-month survival rate after out-of-hospital cardiac arrest because of a higher frequency of ventricular fibrillation/ventricular tachycardia presentation compared with women. Although patients of both sexes with out-of-hospital cardiac arrest initially presenting with ventricular fibrillation/ventricular tachycardia exhibited similar overall survival rates, the rate of survival with favorable neurologic outcome was significantly higher for women than men in the group aged 40 to 59 years.

Women of child-bearing age have better inhospital cardiac arrest survival outcomes than do equal-aged men

OBJECTIVES

Estrogen and progesterone improve neurologic outcomes in experimental models of cardiac arrest and stroke. Our objective was to determine whether women of child-bearing age are more likely than men to survive to hospital discharge after in-hospital cardiac arrest.

DESIGN

Prospective, observational study.

SETTING

Five hundred nineteen hospitals in the National Registry of Cardiopulmonary Resuscitation database.

PATIENTS

Patients included 95,852 men and women 15-44 yrs and 56 yrs or older with pulseless cardiac arrests from January 1, 2000 through July 31, 2008.

MEASUREMENTS AND MAIN RESULTS

Patients were stratified a priori by gender and age groups (15-44 yrs and > or =56 yrs). Fixed-effects regression conditioning on hospital was used to examine the relationship between age, gender, and survival outcomes. The unadjusted survival to discharge rate for younger women of child-bearing age (15-44 yrs) was 19% (940/4887) vs. 17% (1203/7025) for younger men (p = .013). The adjusted hospital discharge difference between these younger women and men was 2.8% (95% confidence interval, 1.0% to 4.6%; p = .002), and these younger women also had a 2.6% (95% confidence interval, 0.9% to 4.3%; p = .002) absolute increase in favorable neurologic outcome. For older women compared with men (> or =56 yrs), there were no demonstrable differences in discharge rates (18% vs. 18%; adjusted difference, -0.1%; 95% confidence interval, -0.9% to 0.6%; p = .68) or favorable neurologic outcome (14% vs. 14%; adjusted difference, -0.1%; 95% confidence interval, -0.7% to 0.5%; p = .74).

CONCLUSIONS

Women of child-bearing age were more likely than comparably aged men to survive to hospital discharge after in-hospital cardiac arrest, even after controlling for etiology of arrest and other important variables.

In-hospital mortality in 13,263 survivors of out-of-hospital cardiac arrest in Canada

BACKGROUND

There is a substantial mortality rate in patients admitted alive after out-of-hospital cardiac arrest. The primary objective of our study was to examine trends in in-hospital survival in out-of-hospital cardiac arrest survivors in Canada between 1994 and 2004. The secondary objective was to examine predictors of in-hospital survival in these patients.

METHODS

Data on hospital admissions from April 1, 1994, to March 31, 2004, were obtained from the Health Person-oriented Information Database, maintained by Statistics Canada. We included all patients with a primary diagnosis of cardiac arrest who survived to hospital admission. We assessed survival to hospital discharge in all patients admitted alive.

RESULTS

In Canada, 13,263 patients survived community arrest between 1994 and 2004. The annual incidence of hospital admission after out-of-hospital cardiac arrest decreased by 33%, from 5.37 per 100,000 in 1994 to 3.63 per 100,000 in 2004 (P < .0001 for trend). Subsequently, 5,045 patients (38.03%) survived to hospital discharge. The survival rate did not change during the duration of the study. Invasive coronary artery disease management was associated with a greatly increased chance of survival (odds ratio 21.98, 95% CI 17.62-27.42). Also male gender, heart failure, and acute myocardial ischemia were independent positive predictors of survival to hospital discharge; greater age and comorbidities were negative predictors of survival. Finally, there were significant interprovincial variations in survival rates.

CONCLUSIONS

Our study, the largest of its kind, has 4 main findings. Firstly, between 1993 and 2004, there was a significant and steady decline in admission rates after community cardiac arrest. Second, there was no change in the in-hospital survival rates. Thirdly, invasive management of coronary artery disease was associated with a greatly improved chance of survival, and finally, there were important regional variations in survival rates.