Trends in survival after cardiac arrest: a Swedish nationwide study over 30 years

The association between GRACE score at admission for myocardial infarction and the incidence of sudden cardiac arrests in long-term follow-up - the MADDEC study

Background. Sudden cardiac arrest (SCA), often also leading to sudden cardiac death (SCD), is a common complication in coronary artery disease. Despite the effort there is a lack of applicable prediction tools to identify those at high risk. We tested the association between the validated GRACE score and the incidence of SCA after myocardial infarction. Material and methods. A retrospective analysis of 1,985 patients treated for myocardial infarction (MI) between January 1st 2015 and December 31st 2018 and followed until the 31st of December of 2021. The main exposure variable was patients' GRACE score at the point of admission and main outcome variable was incident SCA after hospitalization. Their association was analyzed by subdistribution hazard (SDH) model analysis. The secondary endpoints included SCA in patients with no indication to implantable cardioverter-defibrillator (ICD) device and incident SCD. Results. A total of 1985 patients were treated for MI. Mean GRACE score at baseline was 118.7 (SD 32.0). During a median follow-up time of 5.3 years (IQR 3.8-6.1 years) 78 SCA events and 52 SCDs occurred. In unadjusted analyses one SD increase in GRACE score associated with over 50% higher risk of SCA (SDH 1.55, 95% CI 1.29-1.85, p < 0.0001) and over 40% higher risk for SCD (1.42, 1.12-1.79, p = 0.0033). The associations between SCA and GRACE remained statistically significant even with patients without indication for ICD device (1.57, 1.30-1.90, p < 0.0001) as well as when adjusting with patients LVEF and omitting the age from the GRACE score to better represent the severity of the cardiac event. The association of GRACE and SCD turned statistically insignificant when adjusting with LVEF. Conclusions. GRACE score measured at admission for MI associates with long-term risk for SCA.

Nurses' understanding of the necessity of core items recommended by the latest Utstein resuscitation registry template for in-hospital cardiac arrest: A cross-sectional study

Background

It is essential for nurses, who are more likely to be first responders to cardiac arrest patients in hospitals, to understand the items that should be recorded when a cardiac arrest occurs to record the event accurately. We aimed to assess Japanese nurses' understanding of the necessity of recording core items, as defined in the Utstein-style reporting template.

Methods

We conducted a cross-sectional study using an anonymous, self-administered online questionnaire survey at Kyoto University Hospital. In addition to nurses' understanding of the necessity of recording Utstein core items, we collected data on years of experience as a nurse, experiences of encountering in-hospital cardiac arrest (IHCA), and understanding and confidence in performing basic life support.

Results

Of 1,202 eligible nurses, 492 participated, among whom 5.3% were aware of the Utstein-style reporting template. None of the items were considered "necessary" by all respondents. A documentation form listing the items to be recorded was requested by 86% of the respondents, and 82% reported having difficulties due to a lack of opportunities to learn how to write resuscitation documentation.

Conclusion

We found that nurses lacked an understanding of the Utstein-style reporting template, which is critical for effective management and reporting of IHCA. Detailed and accurate documentation is crucial for improving outcomes in patients with IHCA. Effective education for nurses and development of a recording system are challenges that must be addressed in the future.

In-hospital cardiac arrest characteristics, causes and outcomes in patients with cardiovascular disease across different departments: a retrospective study

BACKGROUND

Cardiac etiologies arrest accounts for almost half of all in-hospital cardiac arrest (IHCA), and previous studies have shown that the location of IHCA is an important factor affecting patient outcomes. The aim was to compare the characteristics, causes and outcomes of cardiovascular disease in patients suffering IHCA from different departments of Fuwai hospital in Beijing, China.

METHODS

We included patients who were resuscitated after IHCA at Fuwai hospital between March 2017 and August 2022. We categorized the departments where cardiac arrest occurred as cardiac surgical or non-surgical units. Independent predictors of in-hospital survival were assessed by logistic regression.

RESULTS

A total of 119 patients with IHCA were analysed, 58 (48.7%) patients with cardiac arrest were in non-surgical units, and 61 (51.3%) were in cardiac surgical units. In non-surgical units, acute myocardial infarction/cardiogenic shock (48.3%) was the main cause of IHCA. Cardiac arrest in cardiac surgical units occurred mainly in patients who were planning or had undergone complex aortic replacement (32.8%). Shockable rhythms (ventricular fibrillation/ventricular tachycardia) were observed in approximately one-third of all initial rhythms in both units. Patients who suffered cardiac arrest in cardiac surgical units were more likely to return to spontaneous circulation (59.0% vs. 24.1%) and survive to hospital discharge (40.0% vs. 10.2%). On multivariable regression analysis, IHCA in cardiac surgical units (OR 5.39, 95% CI 1.90-15.26) and a shorter duration of resuscitation efforts (≤ 30 min) (OR 6.76, 95% CI 2.27-20.09) were associated with greater survival rate at discharge.

CONCLUSION

IHCA occurring in cardiac surgical units and a duration of resuscitation efforts less than 30 min were associated with potentially increased rates of survival to discharge.

Self-evaluation of ILCORs ten steps to improve around in-hospital cardiac arrests among Swedish hospitals

Objectives

Recently, ILCOR unveiled the ground-breaking global initiative "Ten Steps Toward Improving In-Hospital Cardiac Arrest" (IHCA).

Aim

To generate a baseline of how well the ten steps currently function in Sweden, in order to better target educational interventions.

Material and methods

A survey was created using an online form application (Google Forms) and sent to CPR coordinators and physicians in charge of CPR at all 74 Swedish hospitals participating in the Swedish Registry for Cardiopulmonary Resuscitation (SRCR). Hospitals were asked to self-evaluate their functionality on each step on a ten-point scale ranging from 1 "Not present or not functioning at all" to 10 "Very well-functioning". Data regarding number of IHCA and their survival during 2018-2022 was gathered from the SRCR.

Results

A total of 34 out of 74 (46%) Swedish hospitals participated in the survey, collectively representing 59% (7,113 out of 12,070) of IHCA cases in SRCR. The responding hospitals were satisfied with the functionality of just over half of the steps currently (median 60%, range 30-90%). The steps with the highest proportion of satisfied hospitals were found for step 6-rapid response systems (85%) and 7-guideline-based resuscitation (94%), while the steps with lowest proportion of satisfied hospitals were found for step 4-goals of treatment (32%) and step 9-person centred culture (18%). About half of participating hospitals expressed intent to prioritise upcoming years' work on step 1- infrastructure, step 3- effective education and step 5- stop preventable IHCA.

Conclusion

The conclusion is that most hospitals judge themselves to be well-functioning on many of the ten steps, but steps involving effective education might need attention, as well as the tolerance for presence of preventable IHCA being low.

The association of depression and patient and resuscitation characteristics with survival after out-of-hospital cardiac arrest: a cohort study

AIMS

Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide, with cardiovascular disease (CVD) being a key risk factor. This study aims to investigate disparities in patient/OHCA characteristics and survival after OHCA among patients with vs. without depression.

METHODS AND RESULTS

This is a retrospective cohort study using data from the AmsteRdam REsuscitation Studies (ARREST) registry from 2008 to 2018. History of comorbidities, including depression, was obtained from the patient's general practitioner. Out-of-hospital cardiac arrest survival was defined as survival at 30 days post-OHCA or hospital discharge. Logistic regression models were used to obtain crude and adjusted odds ratios (ORs) for the association between depression and OHCA survival and possible effect modification by age, sex, and comorbidities. The potential mediating effects of initial heart rhythm and provision of bystander cardiopulmonary resuscitation were explored. Among 5594 OHCA cases, 582 individuals had pre-existing depression. Patients with depression had less favourable patient and OHCA characteristics and lower odds of survival after adjustment for age, sex, and comorbidities [OR 0.65, 95% confidence interval (CI) 0.51-0.82], with similar findings by sex and age groups. The association remained significant among the Utstein comparator group (OR 0.63, 95% CI 0.45-0.89) and patients with return of spontaneous circulation (OR 0.60, 95% CI 0.42-0.85). Initial rhythm and bystander cardiopulmonary resuscitation partially mediated the observed association (by 27 and 7%, respectively).

CONCLUSION

Out-of-hospital cardiac arrest patients with depression presented more frequently with unfavourable patient and OHCA characteristics and had reduced chances of survival. Further investigation into potential pathways is warranted.

Effect of cardiopulmonary resuscitation training for layperson bystanders on outcomes of out-of-hospital cardiac arrest: A prospective multicenter observational study

BACKGROUND

Effective bystander cardiopulmonary resuscitation (CPR) improves outcomes in out-of-hospital cardiac arrest (OHCA) patients. However, the effect of CPR training on the rate of return of spontaneous circulation (ROSC) among laypersons has yet to be thoroughly evaluated.

METHODS

This prospective, multicenter observational study was conducted across 42 centers in Japan. We assessed OHCA patients who received bystander CPR from a layperson, excluding those performed by healthcare staff. The primary outcome was the ROSC rate. Secondary outcomes included pre-hospital ROSC, ROSC after hospital arrival, favorable neurological outcomes, and 30-day survival. Propensity score with inverse probability treatment weighting (IPTW) was used to adjust for confounders, including age, sex, presence or absence of witnesses, and past medical history.

RESULTS

A total of 969 OHCA patients were included, divided into CPR-trained (n = 322) and control (n = 647). Before adjustment, the ROSC rate was higher in the trained group than the control (40.1% vs. 30.1%, P < 0.01). After IPTW adjustment, the trained group showed a significantly higher ROSC rate (36.7% vs. 30.6%; P = 0.02). All secondary outcomes in the trained group were significantly improved before adjustment. After IPTW adjustment, the trained group showed improved rates of pre-hospital ROSC and ROSC after hospital arrival (30.7% vs. 24.0%; P < 0.01, 23.9% vs. 20.7%; P = 0.04). There were no differences in neurological outcomes and 30-day survival.

CONCLUSION

This study demonstrated that CPR training for laypersons was associated with increased ROSC rates in OHCA patients, indicating potential advantages of CPR training for non-healthcare professionals.

Associations between initial heart rhythm and self-reported health among cardiac arrest survivors - A nationwide registry study

BACKGROUND

Non-shockable initial rhythm is a known risk factor for high mortality at cardiac arrest (CA). However, knowledge on its association with self-reported health in CA survivors is still incomplete.

AIM

To examine the associations between initial rhythm and self-reported health in CA survivors.

METHODS

This nationwide study used data from the Swedish Register for Cardiopulmonary Resuscitation 3-6 months post CA. Health status was measured using EQ-5D-5L and psychological distress by the Hospital Anxiety and Depression Scale (HADS). Kruskal-Wallis test was used to examine differences in self-reported health between groups of different initial rhythms. To control for potential confounders, age, sex, place of CA, aetiology, witnessed status, time to CPR, time to defibrillation, and neurological function were included as covariates in multiple regression analyses for continuous and categorical outcomes.

RESULTS

The study included 1783 adult CA survivors. Overall, the CA survivors reported good health status and symptoms of anxiety or depression were uncommon (13.7% and 13.9% respectively). Survivors with PEA and asystole reported significantly more problems in all dimensions of health status (p = 0.037 to p < 0.001), anxiety (p = 0.034), and depression (p = 0.017) compared to VT/VF. Overall, these differences did not remain in the adjusted regression analyses.

CONCLUSIONS

Initial rhythm is not associated with self-reported health when potential confounders are controlled. Initial rhythm seems to be an indicator of unfavourable factors causing the arrest, or factors related to characteristics and treatment. Therefore, initial rhythm may be used as a proxy for identifying patients at risk for poor outcomes such as worse health status and psychological distress.

HIV status and lay bystander cardiopulmonary resuscitation initiation for witnessed cardiac arrest

INTRODUCTION

Early initiation of cardiopulmonary resuscitation (CPR) by bystanders of out-of-hospital cardiac arrest (OHCA) significantly improves survival and neurological outcomes. However, misconceptions about human immunodeficiency virus (HIV) transmission risk during CPR can deter lay bystanders from performing resuscitation. The aim of this study was to compare the rate of CPR initiation by lay bystanders who witnessed OHCA in subjects with and without HIV infection.

METHODS

We analysed data from the two French cardiac arrest registries (SDEC and RéAC) from 2012 to 2020. We identified HIV-positive individuals from the French National Health Insurance database for the SDEC registry, and directly from the RéAC registry data. We used logistic regression models to assess the association between CPR initiation by lay bystanders and the victim's HIV status.

RESULTS

Of 58,177 witnessed OHCA cases, 192 (0.3%) occurred in HIV-positive subjects. These individuals were younger, more often male, and presented more shockable initial rhythms compared with subjects without HIV. Overall, there was no difference in the CPR initiation rate according to the HIV status (57.3% vs 47.6%, adjusted odds ratio 1.11, 95% confidence interval 0.83-1.48). The CPR initiation rate also did not differ by location between victims with or without HIV (home: 57.7% vs 45.4%; public places: 56.0% vs 53.6%; p for interaction = 0.46). Survival and neurological outcomes at hospital discharge did not differ based on the HIV status.

CONCLUSIONS

This study revealed that the rate of CPR initiation by lay bystanders did not differ between HIV and non-HIV subjects during OHCA.

Importance of hospital and clinical factors for early mortality in Takotsubo syndrome: Insights from the Swedish Coronary Angiography and Angioplasty Registry

BACKGROUND

Takotsubo syndrome (TTS) is an acute heart failure syndrome with symptoms similar to acute myocardial infarction. TTS is often triggered by acute emotional or physical stress and is a significant cause of morbidity and mortality. Predictors of mortality in patients with TS are not well understood, and there is a need to identify high-risk patients and tailor treatment accordingly. This study aimed to assess the importance of various clinical factors in predicting 30-day mortality in TTS patients using a machine learning algorithm.

METHODS

We analyzed data from the nationwide Swedish Coronary Angiography and Angioplasty Registry (SCAAR) for all patients with TTS in Sweden between 2015 and 2022. Gradient boosting was used to assess the relative importance of variables in predicting 30-day mortality in TTS patients.

RESULTS

Of 3,180 patients hospitalized with TTS, 76.0% were women. The median age was 71.0 years (interquartile range 62-77). The crude all-cause mortality rate was 3.2% at 30 days. Machine learning algorithms by gradient boosting identified treating hospitals as the most important predictor of 30-day mortality. This factor was followed in significance by the clinical indication for angiography, creatinine level, Killip class, and age. Other less important factors included weight, height, and certain medical conditions such as hyperlipidemia and smoking status.

CONCLUSIONS

Using machine learning with gradient boosting, we analyzed all Swedish patients diagnosed with TTS over seven years and found that the treating hospital was the most significant predictor of 30-day mortality.

Aetiology and predictors of outcome in non-shockable in-hospital cardiac arrest: A retrospective cohort study from the Swedish Registry for Cardiopulmonary Resuscitation

BACKGROUND

Non-shockable in-hospital cardiac arrest (IHCA) is a condition with diverse aetiology, predictive factors, and outcome. This study aimed to compare IHCA with initial asystole or pulseless electrical activity (PEA), focusing specifically on their aetiologies and the significance of predictive factors.

METHODS

Using the Swedish Registry of Cardiopulmonary Resuscitation, adult non-shockable IHCA cases from 2018 to 2022 (n = 5788) were analysed. Exposure was initial rhythm, while survival to hospital discharge was the primary outcome. A random forest model with 28 variables was used to generate permutation-based variable importance for outcome prediction.

RESULTS

Overall, 60% of patients (n = 3486) were male and the median age was 75 years (IQR 67-81). The most frequent arrest location (46%) was on general wards. Comorbidities were present in 79% of cases and the most prevalent comorbidity was heart failure (33%). Initial rhythm was PEA in 47% (n = 2702) of patients, and asystole in 53% (n = 3086). The most frequent aetiologies in both PEA and asystole were cardiac ischemia (24% vs. 19%, absolute difference [AD]: 5.4%; 95% confidence interval [CI] 3.0% to 7.7%), and respiratory failure (14% vs. 13%, no significant difference). Survival was higher in asystole (24%) than in PEA (17%) (AD: 7.3%; 95% CI 5.2% to 9.4%). Cardiopulmonary resuscitation (CPR) durations were longer in PEA, 18 vs 15 min (AD 4.9 min, 95% CI 4.0-5.9 min). The duration of CPR was the single most important predictor of survival across all subgroup and sensitivity analyses. Aetiology ranked as the second most important predictor in most analyses, except in the asystole subgroup where responsiveness at cardiac arrest team arrival took precedence.

CONCLUSIONS

In this nationwide registry study of non-shockable IHCA comparing asystole to PEA, cardiac ischemia and respiratory failure were the predominant aetiologies. Duration of CPR was the most important predictor of survival, followed by aetiology. Asystole was associated with higher survival compared to PEA, possibly due to shorter CPR durations and a larger proportion of reversible aetiologies.

Assessing feasibility of proposed extracorporeal cardiopulmonary resuscitation programmes for out-of-hospital cardiac arrest in Scotland via geospatial modelling

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) can improve survival for refractory out-of-hospital cardiac arrest (OHCA). We sought to assess the feasibility of a proposed ECPR programme in Scotland, considering both in-hospital and pre-hospital implementation scenarios.

METHODS

We included treated OHCAs in Scotland aged 16-70 between August 2018 and March 2022. We defined those clinically eligible for ECPR as patients where the initial rhythm was ventricular fibrillation, ventricular tachycardia, or pulseless electrical activity, and where pre-hospital return of spontaneous circulation was not achieved. We computed the call-to-ECPR access time interval as the amount of time from emergency medical service (EMS) call reception to either arrival at an ECPR-ready hospital or arrival of a pre-hospital ECPR crew. We determined the number of patients that had access to ECPR within 45 min, and estimated the number of additional survivors as a result.

RESULTS

A total of 6,639 OHCAs were included in the geospatial modelling, 1,406 of which were eligible for ECPR. Depending on the implementation scenario, 52.9-112.6 (13.8-29.4%) OHCAs per year had a call-to-ECPR access time within 45 min, with pre-hospital implementation scenarios having greater and earlier access to ECPR for OHCA patients. We further estimated that an ECPR programme in Scotland would yield 11.8-28.2 additional survivors per year, with the pre-hospital implementation scenarios yielding higher numbers.

CONCLUSION

An ECPR programme for OHCA in Scotland could provide access to ECPR to a modest number of eligible OHCA patients, with pre-hospital ECPR implementation scenarios yielding higher access to ECPR and higher numbers of additional survivors.

Implementation of an extracorporeal resuscitation (ECPR) program for out-of-hospital cardiac arrest in Stockholm, Sweden: Feasibility, safety, and outcome

Background

The aim of this study was to evaluate the implementation of a novel extra corporeal cardiopulmonary (ECPR) program in the greater Stockholm area with focus on feasibility, safety aspects and clinical outcomes.

Methods

Prospective observational study of ECPR program including patients with OHCA from January 2020 to December 2022, fulfilling ECPR criteria: age 18-65 years, initial shockable rhythm or pulseless electrical activity, witnessed arrest, bystander cardiopulmonary resuscitation and refractory arrest after three cycles of advance cardiac life support. The predefined time threshold from collapse to extracorporeal membrane oxygenation (ECMO) initiation was set at 60 min.

Results

We included 95 patients. Of these, 22/95 (23%) had return of spontaneous circulation before ECMO initiation, 39/95 (41%) were excluded for ECMO and 34/95 (36%) had ECMO initiated out of which 23 patients were admitted alive to the ICU. ECMO-initiation within 60 min was met in 9%. In 6 patients vascular access was complicated, 2 patients had severe bleeding at access site requiring intervention. Survival to discharge among all cases was 25% (24/95). Among patients admitted to ICU on ECMO 39% (9/23) survived to discharge, of these 78% had cerebral performance category scale score 1-2 within 12 months. 8 out of 9 survivors had time from OHCA to ECMO-initiation >60 min.

Conclusion

The implementation of an ECPR protocol was feasible without any major, unexpected safety aspects but did not meet the intended target time intervals. Despite this, survival rates were similar to previous studies although most survivors had >60 min to ECMO-initiation.

Traumatic atlanto-occipital dislocation with successfully bystander resuscitation after cardiopulmonary arrest: A case report

This case report describes successful bystander cardiopulmonary resuscitation after a cardiopulmonary arrest due to a traffic accident, followed by early diagnosis and treatment of a traumatic atlanto-occipital dislocation, resulting in successful community reintegration.

Cardiac arrest and post-discharge mortality in patients with myocardial infarction: A large-scale nationwide registry analysis

Background

Cardiac arrest is a serious complication of acute myocardial infarction. The implementation of contemporary approaches to acute myocardial infarction management, including urgent revascularization procedures, has led to significant improvements in short-term outcomes. However, the extent of post-discharge mortality in patients experiencing cardiac arrest during acute myocardial infarction remains uncertain. This study aimed to determine the post-discharge outcomes of patients with cardiac arrest.

Methods

We analysed data from the J-PCI OUTCOME registry, a Japanese prospectively planed, observational, multicentre, national registry of percutaneous coronary intervention involving consecutive patients from 172 institutions who underwent percutaneous coronary intervention and were discharged. Patients who underwent percutaneous coronary intervention for acute myocardial infarction between January 2017 and December 2018 and survived for 30 days were included. Mortality in patients with and without cardiac arrest from 30 days to 1 year after percutaneous coronary intervention for acute myocardial infarction was compared.

Results

Of the 26,909 patients who survived for 30 days after percutaneous coronary intervention for acute myocardial infarction, 1,567 (5.8%) had cardiac arrest at the onset of acute myocardial infarction. Patients with cardiac arrest were younger and more likely to be males than patients without cardiac arrest. The 1-year all-cause mortality was significantly higher in patients with cardiac arrest than in those without (11.9% vs. 2.8%, p < 0.001) for all age groups. Multivariable analysis showed that cardiac arrest was an independent predictor of all-cause long-term mortality (hazard ratio: 2.94; 95% confidence interval: 2.29-3.76).

Conclusions

Patients with acute myocardial infarction and concomitant cardiac arrest have a worse prognosis for up to 1 year after percutaneous coronary intervention than patients without cardiac arrest.

Post-intensive care syndrome and health-related quality of life in long-term survivors of cardiac arrest: a prospective cohort study

Patients discharged from intensive care are at risk for post-intensive care syndrome (PICS), which consists of physical, psychological, and/or neurological impairments. This study aimed to analyze PICS at 24 months follow-up, to identify potential risk factors for PICS, and to assess health-related quality of life in a long-term cohort of adult cardiac arrest survivors. This prospective cohort study included adult cardiac arrest survivors admitted to the intensive care unit of a Swiss tertiary academic medical center. The primary endpoint was the prevalence of PICS at 24 months follow-up, defined as impairments in physical (measured through the European Quality of Life 5-Dimensions-3-Levels instrument [EQ-5D-3L]), neurological (defined as Cerebral Performance Category Score > 2 or Modified Rankin Score > 3), and psychological (based on the Hospital Anxiety and Depression Scale and the Impact of Event Scale-Revised) domains. Among 107 cardiac arrest survivors that completed the 2-year follow-up, 46 patients (43.0%) had symptoms of PICS, with 41 patients (38.7%) experiencing symptoms in the physical domain, 16 patients (15.4%) in the psychological domain, and 3 patients (2.8%) in the neurological domain. Key predictors for PICS in multivariate analyses were female sex (adjusted odds ratio [aOR] 3.17, 95% CI 1.08 to 9.3), duration of no-flow interval during cardiac arrest (minutes) (aOR 1.17, 95% CI 1.02 to 1.33), post-discharge job-loss (aOR 31.25, 95% CI 3.63 to 268.83), need for ongoing psychological support (aOR 3.64, 95% CI 1.29 to 10.29) or psychopharmacologic treatment (aOR 9.49, 95% CI 1.9 to 47.3), and EQ-visual analogue scale (points) (aOR 0.88, 95% CI 0.84 to 0.93). More than one-third of cardiac arrest survivors experience symptoms of PICS 2 years after resuscitation, with the highest impairment observed in the physical and psychological domains. However, long-term survivors of cardiac arrest report intact health-related quality of life when compared to the general population. Future research should focus on appropriate prevention, screening, and treatment strategies for PICS in cardiac arrest patients.

Sex Differences in Out-of-Hospital Cardiac Arrest Survival Trends

BACKGROUND

Out-of-hospital cardiac arrest survival rates have improved over time. This study established whether improvements were similar for women and men, and to what extent resuscitation characteristics or in-hospital procedures contributed to sex differences in temporal trends.

METHODS AND RESULTS

This retrospective cohort study included 3386 women and 8564 men from North Holland, the Netherlands, who experienced an out-of-hospital cardiac arrest from a cardiac cause in 2005 to 2017. Yearly rates of 30-day survival and secondary outcomes were calculated. Sex differences in temporal trends were evaluated with age-adjusted Poisson regression analysis, including interaction for sex and out-of-hospital cardiac arrest year. Resuscitation characteristics and in-hospital procedures were added to the model, and a spline at 2013 was considered. During the study period, the average 30-day survival was 24.9% in men and 15.7% in women. The 30-day survival rate increased in men (20% to 27.2%; P<0.001) but not in women (15.0% to 11.6%; P=0.40). The increase in the 30-day survival rate was 3% higher per year in men than in women (rate ratio, 1.03 [95% CI, 1.00-1.05]), with a stronger difference after 2013. Men had a larger increase in survival rate to the hospital arrival than women in 2005 to 2013, and, after 2013, an advantage over women in survival rate after hospital arrival. The sex differences were partly explained by differing trends in shockable initial rhythm (eg, adjusted rate ratio, 1.01 [95% CI, 0.99-1.03] for 30-day survival) and provision of in-hospital procedures.

CONCLUSIONS

Changes in rates of 30-day survival, survival to hospital arrival, and, after 2013, survival from hospital arrival to 30 days were more beneficial in men than women. The differences in trends were partly explained by shockable initial rhythm and in-hospital procedures.

Sex disparities in bystander defibrillation for out-of-hospital cardiac arrest

Background

Previous studies have suggested that females experiencing out-of-hospital cardiac arrest (OHCA) receive lower rates of both bystander cardiopulmonary resuscitation (CPR) and defibrillation compared to males. Whether this disparity has improved over time is unknown.

Methods

A state-wide OHCA registry in Victoria, Australia collected data over twenty years (2002-2021) regarding rates of bystander interventions in OHCA. Characteristics and outcomes of each OHCA were compared with logistic regression according to sex and time (defined in two-year periods).

Results

32,502 OHCAs were included (69.7% male). Both bystander CPR and defibrillation rates increased for females over time (p < 0.0001). There was no sex disparity in receipt of bystander CPR after adjustment for baseline differences. Females were less likely than males to receive bystander defibrillation, with sex disparity increasing from 2010 onwards (adjOR 0.26 (95%CI 0.09-0.80) in 2020-21 for females compared to males).

Conclusion

Initiatives to increase bystander CPR and defibrillation have resulted in higher overall rates of bystander interventions in the last two decades and no significant sex differences in provision of bystander CPR. However, females receive less bystander defibrillation than males, and sex disparity is increasing. Strategies to promote bystander defibrillation in females experiencing OHCA with a shockable rhythm should be a priority.

Challenges & barriers for real-time integration of drones in emergency cardiac care: Lessons from the United States, Sweden, & Canada

Importance

Out-of-hospital cardiac arrest (OHCA) is a leading cause of morbidity and mortality in the US and Europe (∼600,000 incident events annually) and around the world (∼3.8 million). With every minute that passes without cardiopulmonary resuscitation or defibrillation, the probability of survival decreases by 10%. Preliminary studies suggest that uncrewed aircraft systems, also known as drones, can deliver automated external defibrillators (AEDs) to OHCA victims faster than ground transport and potentially save lives.

Objective

To date, the United States (US), Sweden, and Canada have made significant contributions to the knowledge base regarding AED-equipped drones. The purpose of this Special Communication is to explore the challenges and facilitators impacting the progress of AED-equipped drone integration into emergency medicine research and applications in the US, Sweden, and Canada. We also explore opportunities to propel this innovative and important research forward.

Evidence review

In this narrative review, we summarize the AED-drone research to date from the US, Sweden, and Canada, including the first drone-assisted delivery of an AED to an OHCA. Further, we compare the research environment, emergency medical systems, and aviation regulatory environment in each country as they apply to OHCA, AEDs, and drones. Finally, we provide recommendations for advancing research and implementation of AED-drone technology into emergency care.

Findings

The rates that drone technologies have been integrated into both research and real-life emergency care in each country varies considerably. Based on current research, there is significant potential in incorporating AED-equipped drones into the chain of survival for OHCA emergency response. Comparing the different environments and systems in each country revealed ways that each can serve as a facilitator or barrier to future AED-drone research.

Conclusions and relevance

The US, Sweden, and Canada each offers different challenges and opportunities in this field of research. Together, the international community can learn from one another to optimize integration of AED-equipped drones into emergency systems of care.

Long-term survival after cardiac arrest in patients undergoing emergent coronary angiography

AIM

To determine long-term survival of patients after cardiac arrest undergoing emergent coronary angiography and therapeutic hypothermia.

METHODS

We analysed data from patients treated within the regional STEMI Network from January 2015 to December 2020. The primary endpoint was all-cause mortality at median follow-up. Secondary endpoints were periprocedural complications (arrhythmias, pulmonary edema, cardiogenic shock, mechanical complication, stent thrombosis, reinfarction, bleeding) and 6-month all-cause death. A landmark analysis was performed, studying two time periods; 0-6 months and beyond 6 months.

RESULTS

From a total of 24,125 patients in the regional STEMI network, 494 patients who suffered from cardiac arrest were included and divided into two groups: treated with (n = 119) and without therapeutic hypothermia (n = 375). At median follow-up (16.0 [0.2-33.3] months), there was no difference in the adjusted mortality rate between groups (51.3 % with hypothermia vs 48.0 % without hypothermia; HRadj1.08 95%CI [0.77-1.53]; p = 0.659). There was a higher frequency of bleeding in the hypothermia group (6.7 % vs 1.1 %; ORadj 7.99 95%CI [2.05-31.2]; p = 0.002), without difference for the rest of periprocedural complications. At 6-month follow-up, adjusted all-cause mortality rate was similar between groups (46.2 % with hypothermia vs 44.5 % without hypothermia; HRadj1.02 95%CI [0.71-1.47]; p = 0.900). Also, no differences were observed in the adjusted mortality rate between 6 months and median follow-up (9.4 % with hypothermia vs 6.3 % without hypothermia; HRadj2.02 95%CI [0.69-5.92]; p = 0.200).

CONCLUSIONS

In a large cohort of patients with cardiac arrest within a regional STEMI network, those treated with therapeutic hypothermia did not improve long-term survival compared to those without hypothermia.

Early ICD implantation following out-of-hospital cardiac arrest: a retrospective cohort study from the Swedish Registry for Cardiopulmonary Resuscitation

BACKGROUND

It is unclear whether an implantable cardioverter-defibrillator (ICD) is generally beneficial in survivors of out-of-hospital cardiac arrest (OHCA).

OBJECTIVE

We studied the association between ICD implantation prior to discharge and survival in patients with cardiac aetiology or initial shockable rhythm in OHCA.

DESIGN

We conducted a retrospective cohort study in the Swedish Registry for Cardiopulmonary Resuscitation. Treatment associations were estimated using propensity scores. We used gradient boosting, Bayesian additive regression trees, neural networks, extreme gradient boosting and logistic regression to generate multiple propensity scores. We selected the model yielding maximum covariate balance to obtain weights, which were used in a Cox regression to calculate HRs for death or recurrent cardiac arrest.

PARTICIPANTS

All cases discharged alive during 2010 to 2020 with a cardiac aetiology or initial shockable rhythm were included. A total of 959 individuals were discharged with an ICD, and 2046 were discharged without one.

RESULTS

Among those experiencing events, 25% did so within 90 days in the ICD group, compared with 52% in the other group. All HRs favoured ICD implantation. The overall HR (95% CI) for ICD versus no ICD was 0.38 (0.26 to 0.56). The HR was 0.42 (0.28 to 0.63) in cases with initial shockable rhythm; 0.18 (0.06 to 0.58) in non-shockable rhythm; 0.32 (0.20 to 0.53) in cases with a history of coronary artery disease; 0.36 (0.22 to 0.61) in heart failure and 0.30 (0.13 to 0.69) in those with diabetes. Similar associations were noted in all subgroups.

CONCLUSION

Among survivors of OHCA, those discharged with an ICD had approximately 60% lower risk of death or recurrent cardiac arrest. A randomised trial is warranted to study this further.

Artificial Intelligence Model Predicts Sudden Cardiac Arrest Manifesting With Pulseless Electric Activity Versus Ventricular Fibrillation

BACKGROUND

There is no specific treatment for sudden cardiac arrest (SCA) manifesting as pulseless electric activity (PEA) and survival rates are low; unlike ventricular fibrillation (VF), which is treatable by defibrillation. Development of novel treatments requires fundamental clinical studies, but access to the true initial rhythm has been a limiting factor.

METHODS

Using demographics and detailed clinical variables, we trained and tested an AI model (extreme gradient boosting) to differentiate PEA-SCA versus VF-SCA in a novel setting that provided the true initial rhythm. A subgroup of SCAs are witnessed by emergency medical services personnel, and because the response time is zero, the true SCA initial rhythm is recorded. The internal cohort consisted of 421 emergency medical services-witnessed out-of-hospital SCAs with PEA or VF as the initial rhythm in the Portland, Oregon metropolitan area. External validation was performed in 220 emergency medical services-witnessed SCAs from Ventura, CA.

RESULTS

In the internal cohort, the artificial intelligence model achieved an area under the receiver operating characteristic curve of 0.68 (95% CI, 0.61-0.76). Model performance was similar in the external cohort, achieving an area under the receiver operating characteristic curve of 0.72 (95% CI, 0.59-0.84). Anemia, older age, increased weight, and dyspnea as a warning symptom were the most important features of PEA-SCA; younger age, chest pain as a warning symptom and established coronary artery disease were important features associated with VF.

CONCLUSIONS

The artificial intelligence model identified novel features of PEA-SCA, differentiated from VF-SCA and was successfully replicated in an external cohort. These findings enhance the mechanistic understanding of PEA-SCA with potential implications for developing novel management strategies.

Cardiac Catheterization Laboratory Management of the Comatose Adult Patient With an Out-of-Hospital Cardiac Arrest: A Scientific Statement From the American Heart Association

Out-of-hospital cardiac arrest is a leading cause of death, accounting for ≈50% of all cardiovascular deaths. The prognosis of such individuals is poor, with <10% surviving to hospital discharge. Survival with a favorable neurologic outcome is highest among individuals who present with a witnessed shockable rhythm, received bystander cardiopulmonary resuscitation, achieve return of spontaneous circulation within 15 minutes of arrest, and have evidence of ST-segment elevation on initial ECG after return of spontaneous circulation. The cardiac catheterization laboratory plays an important role in the coordinated Chain of Survival for patients with out-of-hospital cardiac arrest. The catheterization laboratory can be used to provide diagnostic, therapeutic, and resuscitative support after sudden cardiac arrest from many different cardiac causes, but it has a unique importance in the treatment of cardiac arrest resulting from underlying coronary artery disease. Over the past few years, numerous trials have clarified the role of the cardiac catheterization laboratory in the management of resuscitated patients or those with ongoing cardiac arrest. This scientific statement provides an update on the contemporary approach to managing resuscitated patients or those with ongoing cardiac arrest.

Out-of-Hospital Cardiac Arrest Following the COVID-19 Pandemic

Importance

Out-of-hospital cardiac arrest (OHCA) health care provision may be a good indicator of the recovery of the health care system involved in OHCA care following the COVID-19 pandemic. There is a lack of data regarding outcomes capable of verifying this recovery.

Objective

To determine whether return to spontaneous circulation, overall survival, and survival with good neurological outcome increased in patients with OHCA since the COVID-19 pandemic was brought under control in 2022 compared with prepandemic and pandemic levels.

Design, Setting, and Participants

This observational cohort study was conducted to examine health care response and survival with good neurological outcome at hospital discharge in patients treated following OHCA. A 3-month period, including the first wave of the pandemic (February 1 to April 30, 2020), was compared with 2 periods before (April 1, 2017, to March 31, 2018) and after (January 1 to December 31, 2022) the pandemic. Data analysis was performed in July 2023. Emergency medical services (EMS) serving a population of more than 28 million inhabitants across 10 Spanish regions participated. Patients with OHCA were included if participating EMS initiated resuscitation or continued resuscitation initiated by a first responder.

Exposure

The pandemic was considered to be under control following the official declaration that infection with SARS-CoV-2 was to be considered another acute respiratory infection.

Main Outcome and Measures

The main outcomes were return of spontaneous circulation, overall survival, and survival at hospital discharge with good neurological outcome, expressed as unimpaired or minimally impaired cerebral performance.

Results

A total of 14 732 patients (mean [SD] age, 64.2 [17.2] years; 10 451 [71.2%] male) were included, with 6372 OHCAs occurring during the prepandemic period, 1409 OHCAs during the pandemic period, and 6951 OHCAs during the postpandemic period. There was a higher incidence of OHCAs with a resuscitation attempt in the postpandemic period compared with the pandemic period (rate ratio, 4.93; 95% CI, 4.66-5.22; P < .001), with lower incidence of futile resuscitation for OHCAs (2.1 per 100 000 person-years vs 1.3 per 100 000 person-years; rate ratio, 0.81; 95% CI, 0.71-0.92; P < .001). Recovery of spontaneous circulation at hospital admission increased from 20.5% in the pandemic period to 30.5% in the postpandemic period (relative risk [RR], 1.08; 95% CI, 1.06-1.10; P < .001). In the same way, overall survival at discharge increased from 7.6% to 11.2% (RR, 1.45; 95% CI, 1.21-1.75; P < .001), with 6.6% of patients being discharged with good neurological status (Cerebral Performance Category Scale categories 1-2) in the pandemic period compared with 9.6% of patients in the postpandemic period (RR, 1.07; 95% CI, 1.04-1.10; P < .001).

Conclusions and Relevance

In this cohort study, survival with good neurological outcome at hospital discharge following OHCA increased significantly after the COVID-19 pandemic.

Trends in Incidence and Outcomes of Cardiac Arrest Occurring in Swedish ICUs

OBJECTIVE

To determine temporal trends in the incidence of cardiac arrest occurring in the ICU (ICU-CA) and its associated long-term mortality.

DESIGN

Retrospective observational study.

SETTING

Swedish ICUs, between 2011 and 2017.

PATIENTS

Adult patients (≥18 yr old) recorded in the Swedish Intensive Care Registry (SIR).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

ICU-CA was defined as a first episode of cardiopulmonary resuscitation and/or defibrillation following an ICU admission, as recorded in SIR or the Swedish Cardiopulmonary Resuscitation Registry. Annual adjusted ICU-CA incidence trend (all admissions) was estimated using propensity score-weighted analysis. Six-month mortality trends (first admissions) were assessed using multivariable mixed-effects logistic regression. Analyses were adjusted for pre-admission characteristics (sex, age, socioeconomic status, comorbidities, medications, and healthcare utilization), illness severity on ICU admission, and admitting unit. We included 231,427 adult ICU admissions. Crude ICU-CA incidence was 16.1 per 1,000 admissions, with no significant annual trend in the propensity score-weighted analysis. Among 186,530 first admissions, crude 6-month mortality in ICU-CA patients was 74.7% (95% CI, 70.1-78.9) in 2011 and 68.8% (95% CI, 64.4-73.0) in 2017. When controlling for multiple potential confounders, the adjusted 6-month mortality odds of ICU-CA patients decreased by 6% per year (95% CI, 2-10). Patients admitted after out-of-hospital or in-hospital cardiac arrest had the highest ICU-CA incidence (136.1/1,000) and subsequent 6-month mortality (76.0% [95% CI, 73.6-78.4]).

CONCLUSIONS

In our nationwide Swedish cohort, the adjusted incidence of ICU-CA remained unchanged between 2011 and 2017. More than two-thirds of patients with ICU-CA did not survive to 6 months following admission, but a slight improvement appears to have occurred over time.

The Latest in Resuscitation Research: Highlights From the 2022 American Heart Association's Resuscitation Science Symposium

BACKGROUND

Every year the American Heart Association's Resuscitation Science Symposium (ReSS) brings together a community of international resuscitation science researchers focused on advancing cardiac arrest care.

METHODS AND RESULTS

The American Heart Association's ReSS was held in Chicago, Illinois from November 4th to 6th, 2022. This annual narrative review summarizes ReSS programming, including awards, special sessions and scientific content organized by theme and plenary session.

CONCLUSIONS

By exploring both the science of resuscitation and important related topics including survivorship, disparities, and community-focused programs, this meeting provided important resuscitation updates.

In-hospital cardiac arrest due to sepsis - Aetiologies and outcomes in a Swedish cohort study

Objectives

Awareness of causes of cardiac arrest is essential to prevent them. A recent review found that almost every sixth in-hospital cardiac arrest is caused by infection. Few studies have explored how infections cause cardiac arrest.

Aim

To describe the features, mechanisms and outcome of sepsis-related cardiac arrests.

Material and methods

All patients ≥18 years who suffered a cardiac arrest at Karolinska University Hospital between 2007 and 2022 with sepsis as the primary cause were included. Data were collected the Swedish Registry for Cardiopulmonary Resuscitation and medical records. The primary outcome was survival to discharge.

Results

Out of 2,327 in-hospital cardiac arrests, 5% (n = 123) suffered it due to sepsis, and 17% (21) survived to hospital discharge. Two thirds of patients were admitted to the hospital due to sepsis and suffered their cardiac arrest after a median of four days. About half (n = 59) had deranged vital signs before the event. Most were witnessed in general wards. In all, 47% (n = 58) had asystole and 24% (n = 30) as the first heart rhythm. The respiratory tract was the most common source of infection. Most patients were undergoing antibiotic therapy and one third had a positive microbiological culture with mixed gram-positive bacteria or Escherichia coli in the urine.

Conclusion

Our results suggest that sepsis is an uncommon and not increasing cause of in-hospital cardiac arrest and its outcome is in line with other non-shockable cardiac arrests. Deranged respiratory and/or circulatory vital signs precede the event.

Characteristics, survival and neurological outcome in out-of-hospital cardiac arrest in young adults in Sweden: A nationwide study

Aim

The aim of this study was to present a comprehensive overview of out-of-hospital cardiac arrests (OHCA) in young adults.

Methods

The data set analyzed included all cases of OHCA from 1990 to 2020 in the age-range 16-49 years in the Swedish Registry of Cardiopulmonary Resuscitation (SRCR). OHCA between 2010 and 2020 were analyzed in more detail. Clinical characteristics, survival, neurological outcomes, and long-time trends in survival were studied. Logistic regression was used to study 30-days survival, neurological outcomes and Utstein determinants of survival.

Results

Trends were assessed in 11,180 cases. The annual increase in 30-days survival during 1990-2020 was 5.9% with no decline in neurological function among survivors. Odds ratio (OR) for heart disease as the cause was 0.55 (95% CI 0.44 to 0.67) in 2017-2020 compared to 1990-1993. Corresponding ORs for overdoses and suicide attempts were 1.61 (95% CI 1.23-2.13) and 2.06 (95% CI 1.48-2.94), respectively. Exercise related OHCA was noted in roughly 5%. OR for bystander CPR in 2017-2020 vs 1990-1993 was 3.11 (95% CI 2.57 to 3.78); in 2020 88 % received bystander CPR. EMS response time increased from 6 to 10 minutes.

Conclusion

Survival has increased 6% annually, resulting in a three-fold increase over 30 years, with stable neurological outcome. EMS response time increased with 66% but the majority now receive bystander CPR. Cardiac arrest due to overdoses and suicide attempts are increasing.

To withhold resuscitation - The Swedish system's rules and challenges

The aim of this article is to describe current Swedish legalisation, clinical practice and future perspectives on the medical ethical decision "Do-Not-Attempt-Cardio-Pulmonary-Resuscitation" (DNACPR) in relation to prevent futile resuscitation of in-hospital cardiac arrests. Sweden has about 2200 in-hospital cardiac arrests yearly, with an overall 30-day survival ratio of 35%. This population is highly selected, although the frequency of DNACPR orders for hospitalized patients is unknown, resuscitation is initiated in only 6-13% of patients dying in Swedish hospitals. According to Swedish law and although shared decision making is sought, the physician is the ultimate decision-maker and consultation with the patient, her relatives and another licenced health care practitioner is mandatory. According to studies, these consultations is documented in only about 10% of the decisions. Clinicians lack tools to assess risk of IHCA, tools to predict outcome and we are not good at guessing patients own will. Future directives for clinical practice need to address difficulties for physicians in making decisions as well as the timing of decisions. We conclude that the principles in Swedish law needs to be fulfilled by a more systematic approach to documentation and planning of meetings between patients, relatives and colleagues.

Rapid response team activation prior to in-hospital cardiac arrest: Areas for improvements based on a national cohort study

INTRODUCTION

Rapid response teams (RRTs) are designed to improve the "chain of prevention" of in-hospital cardiac arrest (IHCA). We studied the 30-day survival of patients reviewed by RRTs within 24 hours prior to IHCA, as compared to patients not reviewed by RRTs.

METHODS

A nationwide cohort study based on the Swedish Registry of Cardiopulmonary Resuscitation, between January 1st, 2014, and December 31st, 2021. An explorative, hypothesis-generating additional in-depth data collection from medical records was performed in a small subgroup of general ward patients reviewed by RRTs.

RESULTS

In all, 12,915 IHCA patients were included. RRT-reviewed patients (n = 2,058) had a lower unadjusted 30-day survival (25% vs 33%, p < 0.001), a propensity score based Odds ratio for 30-day survival of 0.92 (95% Confidence interval 0.90-0.94, p < 0.001) and were more likely to have a respiratory cause of IHCA (22% vs 15%, p < 0.001). In the subgroup (n = 82), respiratory distress was the most common RRT trigger, and 24% of the RRT reviews were delayed. Patient transfer to a higher level of care was associated with a higher 30-day survival rate (20% vs 2%, p < 0.001).

CONCLUSION

IHCA preceded by RRT review is associated with a lower 30-day survival rate and a greater likelihood of a respiratory cause of cardiac arrest. In the small explorative subgroup, respiratory distress was the most common RRT trigger and delayed RRT activation was frequent. Early detection of respiratory abnormalities and timely interventions may have a potential to improve outcomes in RRT-reviewed patients and prevent further progress into IHCA.

Long-Term Quality of Life After Out-of-Hospital Cardiac Arrest

Importance

Allocating resources to increase survival after cardiac arrest requires survivors to have a good quality of life, but long-term data are lacking.

Objective

To determine the quality of life of survivors of out-of-hospital cardiac arrest from 2001 to 2019.

Design, Setting, and Participants

This survey study used the EuroQol Health Questionnaire, 12-Item Short Form Health Survey (SF-12), and Hospital Anxiety and Depression Scale (HADS) to assess the health-related quality of life of all adult survivors of out-of-hospital cardiac arrest included in the Danish Cardiac Arrest Registry between June 1, 2001, and August 31, 2019, who were alive in October 2020 (follow-up periods, 0-1, >1-2, >2-4, >4-6, >6-8, >8-10, >10-15, and >15-20 years since arrest). The survey was conducted from October 1, 2020, through May 31, 2021.

Exposure

All patients who experienced an out-of-hospital cardiac arrest.

Main Outcome and Measures

Self-reported health was measured using the EuroQol Health Questionnaire index (EQ index) score and EQ visual analog scale. Physical and mental health were measured using the SF-12, and anxiety and depression were measured using the HADS. Descriptive statistics were used for the analysis.

Results

Of 4545 survivors, 2552 (56.1%) completed the survey, with a median follow-up since their event of 5.5 years (IQR, 2.9-8.9 years). Age was comparable between responders and nonresponders (median [IQR], 67 [58-74] years vs 68 [56-78] years), and 2075 responders (81.3%) were men and 477 (18.7%) women (vs 1473 male [73.9%] and 520 female [26.1%] nonresponders). For the shortest follow-up (0-1 year) and longest follow-up (>15-20 years) groups, the median EQ index score was 0.9 (IQR, 0.7-1.0) and 0.9 (0.8-1.0), respectively. For all responders, the mean (SD) SF-12 physical health score was 43.3 (12.3) and SF-12 mental health score, 52.9 (8.3). All 3 scores were comparable to a general Danish reference population. Based on HADS scores, a low risk for anxiety was reported by 73.0% (54 of 74) of 0- to 1-year survivors vs 89.3% (100 of 112) of greater than 15- to 20-year survivors; for symptoms of depression, these proportions were 79.7% (n = 59) and 87.5% (n = 98), respectively. Health-related quality of life was similar in survivor groups across all follow-up periods.

Conclusions and Relevance

Among this survey study's responders, who comprised more than 50% of survivors of out-of-hospital cardiac arrest in Denmark, long-term health-related quality of life up to 20 years after their event was consistently high and comparable to that of the general population. These findings support resource allocation and efforts targeted to increasing survival after out-of-hospital cardiac arrest.

Comorbidities prior to out-of-hospital cardiac arrest and diagnoses at discharge among survivors

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) has a dismal prognosis with overall survival around 10%. Previous studies have shown conflicting results regarding the prevalence and significance of comorbidities in OHCA, as well as the underlying causes. Previously, 80% of sudden cardiac arrest have been attributed to coronary artery disease. We studied comorbidities and discharge diagnoses in OHCA in all of Sweden.

METHODS

We used the Swedish Registry of Cardiopulmonary Resuscitation, merged with the Inpatient Registry and Outpatient Registry to identify patients with OHCA from 2010 to 2020 and to collect all their comorbidities as well as discharge diagnoses (among those admitted to hospital). Patient characteristics were described using means, medians and SD. Survival curves were performed among hospitalised patients with acute myocardial infarction (AMI) as well as heart failure.

RESULTS

A total of 54 484 patients with OHCA were included, of whom 35 894 (66%) were men. The most common comorbidities prior to OHCA were hypertension (43.6%), heart failure (23.6%), chronic ischaemic heart disease (23.6%) and atrial fibrillation (22.0%). Previous AMI was prevalent in 14.8% of men and 10.9% of women. Among women, 18.0% had type 2 diabetes, compared with 19.6% of the men. Among hospitalised patients, 30% were diagnosed with AMI, 27% with hypertension, 20% with ischaemic heart disease and 18% with heart failure as discharge diagnoses.

CONCLUSION

In summary, we find evidence that nowadays a minority of cardiac arrests are due to coronary artery disease and AMIs and its complications. Only 30% of all cases of OHCA admitted to hospital were diagnosed with AMI. Coronary artery disease is now likely in the minority with regard to causes of OHCA.

Danish Drowning Formula for identification of out-of-hospital cardiac arrest from drowning

BACKGROUND

Accurate, reliable, and sufficient data is required to reduce the burden of drowning by targeting preventive measures and improving treatment. Today's drowning statistics are informed by various methods sometimes based on data sources with questionable reliability. These methods are likely responsible for a systematic and significant underreporting of drowning. This study's aim was to assess the 30-day survival of patients with out-of-hospital cardiac arrest (OHCA) identified in the Danish Cardiac Arrest Registry (DCAR) after applying the Danish Drowning Formula.

METHODS

This nationwide, cohort, registry-based study with 30-day follow-up used the Danish Drowning Formula to identify drowning-related OHCA with a resuscitation attempt from the DCAR from January 1st, 2016, through December 31st, 2021. The Danish Drowning Formula is a text-search algorithm constructed for this study based on trigger-words identified from the prehospital medical records of validated drowning cases. The primary outcome was 30-day survival from OHCA. Data were analyzed using multiple logistic regression.

RESULTS

Drowning-related OHCA occurred in 374 (1%) patients registered in the DCAR compared to 29,882 patients with OHCA from other causes. Drowning-related OHCA more frequently occurred at a public location (87% vs 25%, p < 0.001) and were more frequently witnessed by bystanders (80% vs 55%, p < 0.001). Both 30-day and 1-year survival for patients with drowning-related OHCA were significantly higher compared to OHCA from other causes (33% vs 14% and 32% vs 13%, respectively, p < 0.001). The adjusted odds ratio for 30-day survival for drowning-related OHCA and other causes of OHCA was 2.3 [1.7-3.2], p < 0.001. Increased 30-day survival was observed for drowning-related OHCA occurring at swimming pools compared to public location OHCA from other causes with an OR of 11.6 [6.0-22.6], p < 0.001.

CONCLUSIONS

This study found higher 30-day survival among drowning-related OHCA compared to OHCA from other causes. This study proposed that a text-search algorithm (Danish Drowning Formula) could explore unstructured text fields to identify drowning persons. This method may present a low-resource solution to inform the drowning statistics in the future.

REGISTRATION

This study was registered at ClinicalTrials.gov before analyses (NCT05323097).

Restrictive versus high-dose oxygenation strategy in post-arrest management following adult non-traumatic cardiac arrest: a meta-analysis

PURPOSE

Neurological damage is the main cause of death or withdrawal of care in comatose survivors of cardiac arrest (CA). Hypoxemia and hyperoxemia following CA were described as potentially harmful, but reports were inconsistent. Current guidelines lack specific oxygen targets after return of spontaneous circulation (ROSC).

OBJECTIVES

The current meta-analysis assessed the effects of restrictive compared to high-dose oxygenation strategy in survivors of CA.

METHODS

A structured literature search was performed. Randomized controlled trials (RCTs) comparing two competing oxygenation strategies in post-ROSC management after CA were eligible. The primary end point was short-term survival (≤ 90 days). The meta-analysis was prospectively registered in PROSPERO database (CRD42023444513).

RESULTS

Eight RCTs enrolling 1941 patients were eligible. Restrictive oxygenation was applied to 964 patients, high-dose regimens were used in 977 participants. Short-term survival rate was 55.7% in restrictive and 56% in high-dose oxygenation group (8 trials, RR 0.99, 95% CI 0.90 to 1.10, P = 0.90, I2 = 18%, no difference). No evidence for a difference was detected in survival to hospital discharge (5 trials, RR 0.98, 95% CI 0.79 to 1.21, P = 0.84, I2 = 32%). Episodes of hypoxemia more frequently occurred in restrictive oxygenation group (4 trials, RR 2.06, 95% CI 1.47 to 2.89, P = 0.004, I2 = 13%).

CONCLUSION

Restrictive and high-dose oxygenation strategy following CA did not result in differences in short-term or in-hospital survival. Restrictive oxygenation strategy may increase episodes of hypoxemia, even with restrictive oxygenation targets exceeding intended saturation levels, but the clinical relevance is unknown. There is still a wide gap in the evidence of optimized oxygenation in post-ROSC management and specific targets cannot be concluded from the current evidence.

Sex and gender differences in intensive care medicine

Despite significant advancements in critical care medicine, limited attention has been given to sex and gender disparities in management and outcomes of patients admitted to the intensive care unit (ICU). While "sex" pertains to biological and physiological characteristics, such as reproductive organs, chromosomes and sex hormones, "gender" refers more to sociocultural roles and human behavior. Unfortunately, data on gender-related topics in the ICU are lacking. Consequently, data on sex and gender-related differences in admission to the ICU, clinical course, length of stay, mortality, and post-ICU burdens, are often inconsistent. Moreover, when examining specific diagnoses in the ICU, variations can be observed in epidemiology, pathophysiology, presentation, severity, and treatment response due to the distinct impact of sex hormones on the immune and cardiovascular systems. In this narrative review, we highlight the influence of sex and gender on the clinical course, management, and outcomes of the most encountered intensive care conditions, in addition to the potential co-existence of unconscious biases which may also impact critical illness. Diagnoses with a known sex predilection will be discussed within the context of underlying sex differences in physiology, anatomy, and pharmacology with the goal of identifying areas where clinical improvement is needed. To optimize patient care and outcomes, it is crucial to comprehend and address sex and gender differences in the ICU setting and personalize management accordingly to ensure equitable, patient-centered care. Future research should focus on elucidating the underlying mechanisms driving sex and gender disparities, as well as exploring targeted interventions to mitigate these disparities and improve outcomes for all critically ill patients.

A two-point strategy to clarify prognosis in >80 year olds experiencing out of hospital cardiac arrest

BACKGROUND

The global population is aging, with the number of ≥80-year-olds projected to triple over the next 30 years. Rates of out-of-hospital cardiac arrest (OHCA) are also increasing within this age group.

METHODS

The Victorian Ambulance Cardiac Arrest Registry was utilised to identify OHCAs in patients aged ≥80 years between 2002-2021. Predictors of survival to discharge were defined and a prognostic score derived from this cohort.

RESULTS

77,628 patients experienced OHCA of whom 25,269 (32.6%) were ≥80 years (80-90 years = 18,956; 90-100 years = 6,148; >100 years = 209). The number of patients ≥80 years increased over time both absolutely (p = 0.002) and proportionally (p = 0.028). 619 (2.4%) patients survived to discharge without change over time. Older ages had no difference in witnessed OHCA status but were less likely to have shockable rhythm (OR 0.50 (95% CI 0.44-0.57) for 90-100-year-olds, OR 0.28 (95% CI 0.12-0.63) for 90-100-year-olds). If OHCA was witnessed and there was a shockable rhythm then survival was 14%; if one factor was present survival was 5-6% and if neither factor was present, survival was 0.09%. These survival rates enabled derivation of a simplified prognostic assessment score - the '15/5/0' score - highly comparable to a previously-published American cohort.

CONCLUSIONS

Elderly OHCA rates have increased to one-third of caseload. The most important factors predicting survival were whether the OHCA was witnessed and there was a shockable rhythm. We present a simple two-point '15/5/0' prognostic score defining which patients will gain most from advanced resuscitative measures.

Temporal Trends in Incidence and Survival From Sudden Cardiac Arrest Manifesting With Shockable and Nonshockable Rhythms: A 16-Year Prospective Study in a Large US Community

STUDY OBJECTIVE

The proportion of nonshockable sudden cardiac arrests (pulseless electrical activity and asystole) continues to rise. Survival is lower than shockable (ventricular fibrillation [VF]) sudden cardiac arrests, but there is little community-based information on temporal trends in the incidence and survival from sudden cardiac arrests based on presenting rhythms. We investigated community-based temporal trends in sudden cardiac arrest incidence and survival by presenting rhythm.

METHODS

We prospectively evaluated the incidence of each presenting sudden cardiac arrest rhythm and survival outcomes for out-of-hospital events in the Portland, Oregon metro area (population of approximately 1 million, 2002 to 2017). We limited inclusion to cases of likely cardiac cause with resuscitation attempted by emergency medical services.

RESULTS

Out of 3,723 overall sudden cardiac arrest cases, 908 (24%) presented with pulseless electrical activity, 1,513 (41%) with VF, and 1,302 (35%) with asystole. The incidence of pulseless electrical activity-sudden cardiac arrest remained stable over 4-year periods (9.6/100,000 in 2002 to 2005, 7.4/100,000 in 2006 to 2009, 5.7/100,000 in 2010 to 2013, and 8.3/100,000 in 2014 to 2017; unadjusted beta [β] -0.56; 95% confidence interval [CI], -3.98 to 2.85). The incidence of VF-sudden cardiac arrests decreased over time (14.6/100,000 in 2002 to 2005, 13.4/100,000 in 2006 to 2009, 12.0/100,000 in 2010 to 2013, and 11.6/100,000 in 2014 to 2017; unadjusted β -1.05; 95% CI, -1.68 to -0.42) and asystole-sudden cardiac arrests (8.6/100,000 in 2002 to 2005, 9.0/100,000 in 2006 to 2009, 10.3/100,000 in 2010 to 2013, and 15.7/100,000 in 2014 to 2017; unadjusted β 2.25; 95% CI -1.24 to 5.73) did not change significantly over time. Survival increased over time for pulseless electrical activity-sudden cardiac arrests (5.7%, 4.3%, 9.6%, 13.6%; unadjusted β 2.8%; 95% CI 1.3 to 4.4) and VF-sudden cardiac arrests (27.5%, 29.8%, 37.9%, 36.6%; unadjusted β 3.5%; 95% CI 1.4 to 5.6), but not for asystole-sudden cardiac arrests (1.7%, 1.6%, 4.0%, 2.4%; unadjusted β 0.3%; 95% CI, -0.4 to 1.1). Enhancements in the emergency medical services system's pulseless electrical activity-sudden cardiac arrest management were temporally associated with the increasing pulseless electrical activity survival rates.

CONCLUSIONS

Over a 16-year period, the incidence of VF/ventricular tachycardia decreased over time, but pulseless electrical activity incidence remained stable. Survival from both VF-sudden cardiac arrests and pulseless electrical activity-sudden cardiac arrests increased over time with a more than 2-fold increase for pulseless electrical activity-sudden cardiac arrests.

Experiences of family-witnessed cardiopulmonary resuscitation in hospital and its impact on life: An interview study with cardiac arrest survivors and their family members

AIM

To explore experiences of cardiac arrest in-hospital and the impact on life for the patient who suffered the arrest and the family member who witnessed the resuscitation.

BACKGROUND

Guidelines advocate that the family should be offered the option to be present during resuscitation, but little is known about family-witnessed cardiopulmonary resuscitation in hospital and the impact on the patient and their family.

DESIGN

A qualitative design consisting of joint in-depth interviews with patients and family members.

METHODS

Family interviews were conducted with seven patients and their eight corresponding family members (aged 19-85 years) 4-10 months after a family-witnessed in-hospital cardiac arrest. Data were analysed using interpretative phenomenological analysis. The study followed the guidelines outlined in the consolidated criteria for reporting qualitative research (COREQ) checklist.

RESULTS

The participants felt insignificant and abandoned following the in-hospital cardiac arrest. Surviving patients and their close family members felt excluded, alone and abandoned throughout the care process; relationships, emotions and daily life were affected and gave rise to existential distress. Three themes and eight subordinate themes were identified: (1) the intrusion of death-powerless in the face of the fragility of life, highlights what it is like to suffer a cardiac arrest and to cope with an immediate threat to life; (2) being totally exposed-feeling vulnerable in the care relationship, describes how a lack of care from healthcare staff damaged trust; (3) learning to live again-making sense of an existential threat, pertaining to the family's reactions to a difficult event that impacts relationships but also leads to a greater appreciation of life and a positive view of the future.

CONCLUSION

Surviving and witnessing a cardiac arrest in-hospital is a critical event for everyone involved. Patients and family members are vulnerable in this situation and need to be seen and heard, both in the hospital and after hospital discharge. Consequently, healthcare staff need to show compassion and attend to the needs of the family, which involves continually assessing how family members are coping during the process, and providing support and information during and after resuscitation.

RELEVANCE TO CLINICAL PRACTICE

It is important to provide support to family members who witness the resuscitation of a loved one in-hospital. Structured follow-up care is crucial for cardiac arrest survivors and their families. To promote person-centred care, nurses need interprofessional training on how to support family members during resuscitation, and follow-up care focusing on providing resources for multiple challenges faced by survivors (emotional, cognitive, physical) and families (emotional) is needed.

PATIENT OR PUBLIC CONTRIBUTION

In-hospital cardiac arrest patients and family members were involved when designing the study.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

Outcomes of out-of-hospital cardiac arrest in adult congenital heart disease: a Danish nationwide study

AIMS

The risk, characteristics, and outcome of out-of-hospital cardiac arrest (OHCA) in patients with congenital heart disease (CHD) remain scarcely investigated.

METHODS AND RESULTS

An epidemiological registry-based study was conducted. Using time-dependent Cox regression models fitted with a nested case-control design, hazard ratios (HRs) with 95% confidence intervals of OHCA of presumed cardiac cause (2001-19) associated with simple, moderate, and severe CHD were calculated. Moreover, using multiple logistic regression, we investigated the association between pre-hospital OHCA characteristics and 30-day survival and compared 30-day survival in OHCA patients with and without CHD. Overall, 43 967 cases (105 with simple, 144 with moderate, and 53 with severe CHD) and 219 772 controls (median age 72 years, 68.2% male) were identified. Any type of CHD was found to be associated with higher rates of OHCA compared with the background population [simple CHD: HR 1.37 (1.08-1.70); moderate CHD: HR 1.64 (1.36-1.99); and severe CHD: HR 4.36 (3.01-6.30)]. Pre-hospital cardiopulmonary resuscitation and defibrillation were both associated with improved 30-day survival in patients with CHD, regardless of CHD severity. Among patients with OHCA, simple, moderate, and severe CHD had a similar likelihood of 30-day survival compared with no CHD [odds ratio 0.95 (0.53-1.69), 0.70 (0.43-1.14), and 0.68 (0.33-1.57), respectively].

CONCLUSION

A higher risk of OHCA was found throughout the spectrum of CHD. Patients with and without CHD showed the same 30-day survival, which relies on the pre-hospital chain of survival, namely cardiopulmonary resuscitation and defibrillation.

PULS - Austrian Cardiac Arrest Awareness Association: An overview of a multi-tiered and multi-facetted regional initiative to save lives

Background

Out-of-hospital cardiac arrest with subsequent cardiopulmonary resuscitation (CPR) still leads to dismal outcomes worldwide. The crucial gap between cardiac arrest and advanced life support can only be filled by bystander-CPR. However, knowledge and willingness of the public towards basic life support (BLS) remain low. Global and national initiatives for awareness building and CPR training have produced promising improvements, but an additional focus on regional initiatives might be necessary to truly implement change.

Methods and results

In order to support other like-minded groups, we present a "coming of age" narrative review of PULS - Austrian Cardiac Arrest Awareness Association, along with a future outlook and "lessons learned". Interviews with past and present employees, members, and functionaries were conducted by the authors. Additionally, the organization's archives were assessed.

Conclusion

Following current guidelines and the Utstein formula of survival, building a system to save lives is essential to achieve progress concerning cardiac arrest survival and outcomes. As kinds of "regional offices" of global resuscitation efforts, a network of individual local initiatives and organizations such as PULS can carry the respective messages, engage with local key figures of implementation, and keep up perpetual work for cardiac arrest awareness and BLS education.

No obesity paradox in out-of-hospital cardiac arrest: Data from the Swedish registry of cardiopulmonary resuscitation

Background

Although an "obesity paradox", which states an increased chance of survival for patients with obesity after myocardial infarction has been proposed, it is less clear whether this phenomenon even exists in patients suffering out-of-hospital cardiac arrest (OHCA) and if diabetes, which is often associated with obesity, implies an additional risk.

Objective

To investigate if and how obesity, with or without diabetes, affects the survival of patients with OHCA.

Methods

This study included 55,483 patients with OHCA reported to the Swedish Registry of Cardiopulmonary Resuscitation between 2010 and 2020. Patients were classified in five groups: obesity only (Ob), type 1 diabetes only (T1D), type 2 diabetes only (T2D), obesity and any diabetes (ObD), or belonging to the group other (OTH). Patient characteristics and outcomes were studied using descriptive statistics, logistic, and Cox proportional regression.

Results

Obesity only was found in 2.7% of the study cohort, while 3.2% had obesity and any type of diabetes. Ob patients were significantly younger than all other patients (p ≤ 0.001); the 30 day-survival was 9.6% in Ob, and 10.6%, 7.3%, 6.9%, and 12.7% in T1D, T2D, ObD, and OTH, respectively, with OR (95% CI) of 0.69 (0.57-0.82), 0.78 (0.56-1.05), 0.65 (0.59-0.71), and 0.55 (0.45-0.66) for Ob, T1D, T2D, and ObD, respectively (reference group OTH). No time-related trends in 30-days survival were found.

Conclusion

Obesity was present in 6% of the population and was associated with younger age and a 30% reduction in survival; a combination of obesity and diabetes further reduced the survival rate.

Changes in Practice of Controlled Hypothermia after Cardiac Arrest in the Past 20 Years: A Critical Care Perspective

For 20 years, induced hypothermia and targeted temperature management have been recommended to mitigate brain injury and increase survival after cardiac arrest. On the basis of animal research and small clinical trials, the International Liaison Committee on Resuscitation strongly advocated hypothermia at 32-34 °C for 12-24 hours for comatose patients with out-of-hospital cardiac arrest with initial rhythm of ventricular fibrillation or nonperfusing ventricular tachycardia. The intervention was implemented worldwide. In the past decade, hypothermia and targeted temperature management have been investigated in larger clinical randomized trials focusing on target temperature depth, target temperature duration, prehospital versus in-hospital initiation, nonshockable rhythms, and in-hospital cardiac arrest. Systematic reviews suggest little or no effect of delivering the intervention on the basis of the summary of evidence, and the International Liaison Committee on Resuscitation today recommends only to treat fever and keep body temperature below 37.5 °C (weak recommendation, low-certainty evidence). Here we describe the evolution of temperature management for patients with cardiac arrest during the past 20 years and how the accrued evidence has influenced not only the recommendations but also the guideline process. We also discuss possible paths forward in this field, bringing up both whether fever management is at all beneficial for patients with cardiac arrest and which knowledge gaps future clinical trials in temperature management should address.

A narrative review of European public awareness initiatives for cardiac arrest

A high resuscitation rate can lead to better overall survival after cardiac arrest. In Europe, various campaigns in the field of lay resuscitation are achieving up to a threefold increase in survival. As part of the new Systems Saving Lives (SSL) chapter, the European Resuscitation Council (ERC) guidelines recommend cardiac awareness campaigns to engage the broader community. It has been noted that countries with high survival rates after an out-of-hospital cardiac arrest (OHCA) start education in resuscitation techniques at school age. The ERC 2021 guidelines recommend that all schoolchildren should routinely receive CPR training each year. Since 2015, the KIDS SAVE LIVES statement recommended for two hours of instruction per year in all schools worldwide by age of 12. Cardiac awareness campaigns like World Restart a Heart Day (WRAH) are aimed to raise awareness about resuscitation and to train as many people as possible.

Early versus deferred coronary angiography following cardiac arrest. A systematic review and meta-analysis

Aim

The role of early coronary angiography (CAG) in the evaluation of patients presenting with out of hospital cardiac arrest (OHCA) and no ST-elevation myocardial infarction (STE) pattern on electrocardiogram (ECG) has been subject to considerable debate. We sought to assess the impact of early versus deferred CAG on mortality and neurological outcomes in patients with OHCA and no STE.

Methods

OVID MEDLINE, EMBASE, Web of Science and Cochrane Library Register were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines from inception until July 18, 2022. Randomized clinical trials (RCTs) of patients with OHCA without STE that compared early CAG with deferred CAG were included. The primary endpoint was 30-day mortality. Secondary endpoints included mortality at discharge or 30-days, favourable neurology at 30-days, major bleeding, renal failure and recurrent cardiac arrest.

Results

Of the 7,998 citations, 5 RCTs randomizing 1524 patients were included. Meta-analysis showed no difference in 30-day mortality with early versus deferred CAG (OR 1.17, CI 0.91 - 1.49, I² = 27%). There was no difference in favourable neurological outcome at 30 days (OR 0.88, CI 0.52 - 1.49, I² = 63%), major bleeding (OR 0.94, CI 0.33 - 2.68, I² = 39%), renal failure (OR 1.14, CI 0.77 - 1.69, I² = 0%), and recurrent cardiac arrest (OR 1.39, CI 0.79 - 2.43, I² = 0%).

Conclusions

Early CAG was not associated with improved survival and neurological outcomes among patients with OHCA without STE. This meta-analysis does not support routinely performing early CAG in this select patient cohort.

The dramatic increase in sudden cardiac deaths and the alarming low survival: A global call to action to improve outcome with the engagement of tertiary education system

The number of out-of-hospital cardiac arrests, cause of disability and death, has dramatically increased worldwide, but despite the progress, the incidence of survival does not appear to have increased significantly. Bystander cardiopulmonary resuscitation (CPR) remains the principal factor in saving out-of-hospital cardiac arrest victims. Analyzing the immense efforts produced by states and professional organizations to train people in CPR skills for immediate intervention in the occurrence of a cardiac arrest, the primary global strategy is centered on CPR education and training for schoolchildren. But the rate of CPR training remains low, with wide differences among communities. The concept of CPR training for schoolchildren to increase bystander CPR rates needs to be implemented. We suggest a global call to action for the tertiary education system for CPR learning and training, including all undergraduate students regardless of the degree course, as a possible method to improve the traditional CPR training today centered on the secondary education system. Extending CPR training courses to the university educational system could significantly increase the number of people educated in life-saving maneuvers. The final objective is to improve the survival rate of patients with out-of-hospital primary cardiac arrest, which has dramatically increased worldwide.

A more conservative test of sex differences in the treatment and outcome of in-hospital cardiac arrest

BACKGROUND

Studies investigating sex disparities related to treatment and outcome of in-hospital cardiac arrest (IHCA) have produced divergent findings and have typically been unable to adjust for outstanding confounding variables.

OBJECTIVES

The aim was to examine sex differences in treatment and survival following IHCA, using a comprehensive set of control variables including e.g., age, comorbidity, and patient-level socioeconomic status.

METHODS

This retrospective study was based on data from the Swedish Register of Cardiopulmonary Resuscitation and Statistics Sweden. In the primary analyses, logistic regression models and ordinary least square regressions were estimated.

RESULTS

The study included 24,217 patients and the majority (70.4%) were men. In the unadjusted analyses, women had a lower chance of survival after cardiopulmonary resuscitation (CPR) attempt, at hospital discharge (with good neurological function) and at 30 days (p<0.01). In the adjusted regression models, female sex was associated with a higher chance of survival after the CPR attempt (B = 1.09, p<0.01) and at 30-days (B = 1.09, p<0.05). In contrast, there was no significant association between sex and survival to discharge with good neurological outcome. Except for treatment duration (B=-0.07, p<0.01), no significant associations between sex and treatment were identified.

CONCLUSIONS

No signs of treatment disparities or discrimination related to sex were identified. However, women had a better chance of surviving IHCA compared to men. The finding that women went from having a survival disadvantage (unadjusted analysis) to a survival advantage (adjusted analysis) attests to the importance of including a comprehensive set of control variables, when examining sex differences.

In-hospital cardiac arrest: the state of the art

In-hospital cardiac arrest (IHCA) is associated with a high risk of death, but mortality rates are decreasing. The latest epidemiological and outcome data from several cardiac arrest registries are helping to shape our understanding of IHCA. The introduction of rapid response teams has been associated with a downward trend in hospital mortality. Technology and access to defibrillators continues to progress. The optimal method of airway management during IHCA remains uncertain, but there is a trend for decreasing use of tracheal intubation and increased use of supraglottic airway devices. The first randomised clinical trial of airway management during IHCA is ongoing in the UK. Retrospective and observational studies have shown that several pre-arrest factors are strongly associated with outcome after IHCA, but the risk of bias in such studies makes prognostication of individual cases potentially unreliable. Shared decision making and advanced care planning will increase application of appropriate DNACPR decisions and decrease rates of resuscitation attempts following IHCA.