Regional Systems of Care for Out-of-Hospital Cardiac Arrest

Long-Term Outcomes of Out-of-Hospital Cardiac Arrest Care at Regionalized Centers

STUDY OBJECTIVE

It is unknown whether regionalization of postarrest care by interfacility transfer to cardiac arrest receiving centers reduces mortality. We seek to evaluate whether treatment at a cardiac arrest receiving center, whether by direct transport or early interfacility transfer, is independently associated with long-term outcome.

METHODS

We performed a retrospective cohort study including adults resuscitated from out-of-hospital cardiac arrest in southwestern Pennsylvania and neighboring Ohio, West Virginia, and Maryland, which includes approximately 5.7 million residents in urban, suburban, and rural counties. Patients were treated by 1 of 78 ground emergency medical services agencies or 2 air medical transport agencies between January 1, 2010, and November 30, 2014. Our primary exposures of interest were interfacility transfer to a cardiac arrest receiving center within 24 hours of arrest or any treatment at a cardiac arrest receiving center regardless of transfer status. Our primary outcome was vital status, assessed through December 31, 2014, with National Death Index records. We used unadjusted and adjusted survival analyses to test the independent association of cardiac arrest receiving center care, whether through direct or interfacility transport, on mortality.

RESULTS

Overall, 5,217 cases were observed for 3,629 person-years, with 3,865 total deaths. Most patients (82%) were treated at 42 non-cardiac arrest receiving centers with median annual volume of 17 cases (interquartile range 1 to 53 cases per center annually), whereas 18% were cared for at cardiac arrest receiving centers receiving at least 1 interfacility transfer per month. In adjusted models, treatment at a cardiac arrest receiving center was independently associated with reduced hazard of death compared with treatment at a non-cardiac arrest receiving center (adjusted hazard ratio 0.84; 95% confidence interval 0.74 to 0.94). These effects were unchanged when analysis was restricted to patients brought from the scene to the treating hospital. No other hospital characteristic, including total out-of-hospital cardiac arrest patient volume and cardiac catheterization capabilities, independently predicted outcome.

CONCLUSION

Both early interfacility transfer to a cardiac arrest receiving center and direct transport to a cardiac arrest receiving center from the scene are independently associated with reduced mortality.

The Molecular Mechanism and Neuroprotective Effect of Dihydrocapsaicin-Induced Mild Hypothermia After Cardiopulmonary Resuscitation in Rats

To investigate the molecular mechanism of dihydrocapsaicin (DHC)-induced mild hypothermia in rats, and to compare its protective effect on the central nervous system with that of a conventional method of inducing hypothermia, 24 healthy male Sprague Dawley rats were randomly divided into four groups based on the following conditions: control group, cardiopulmonary resuscitation (CPR) group, body surface cooling group, and DHC group. Tracheal clipping was used to mimic asphyxia arrest. Rats were assessed for their neurological deficit scores. After sacrifice, immunohistochemical staining was used to examine caspase-3 expression in the cerebral cortex and TRPV1 (transient receptor potential vanilloid subfamily, member 1) expression in the hypothalamus. Terminal TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining was used to evaluate cell apoptosis in the cerebral cortex. Furthermore, intracellular Ca2+ concentration in the hypothalamus and arginine vasopressin (AVP) concentration in ventral septal tissues were also detected in these four groups. Results of our study showed that neurological deficit scores in the DHC group were significantly higher than those in the CPR and body surface cooling groups (p < 0.05). Caspase-3 expression in the cerebral cortex of control group rats was significantly lower than that in other three groups (p < 0.05). Hypothalamic TRPV1 expression, hypothalamic intracellular Ca2+ concentration, and AVP concentration in the ventral septum in the DHC group were significantly higher than that in the other three groups (p < 0.05). Within these three groups, there were significantly fewer apoptotic cells in the DHC and body surface cooling group rats than in the CPR group rats (p < 0.05). DHC has the neuroprotective effect. DHC induced mild hypothermia and reduces apoptosis through a mechanism whereby DHC activates TRPV1 on hypothalamic cells to cause a large Ca2+ influx, which alters corresponding physiological functions and causes the release of AVP to induce hypothermia.

Out-of-Hospital Cardiac Arrest Resuscitation Systems of Care: A Scientific Statement From the American Heart Association

The American Heart Association previously recommended implementation of cardiac resuscitation systems of care that consist of interconnected community, emergency medical services, and hospital efforts to measure and improve the process of care and outcome for patients with cardiac arrest. In addition, the American Heart Association proposed a national process to develop and implement evidence-based guidelines for cardiac resuscitation systems of care. Significant experience has been gained with implementing these systems, and new evidence has accumulated. This update describes recent advances in the science of cardiac resuscitation systems and evidence of their effectiveness, as well as recent progress in dissemination and implementation throughout the United States. Emphasis is placed on evidence published since the original recommendations (ie, including and since 2010).

Distance to invasive heart centre, performance of acute coronary angiography, and angioplasty and associated outcome in out-of-hospital cardiac arrest: a nationwide study

Aims

To evaluate whether the distance from the site of event to an invasive heart centre, acute coronary angiography (CAG)/percutaneous coronary intervention (PCI) and hospital-level of care (invasive heart centre vs. local hospital) is associated with survival in out-of-hospital cardiac arrest (OHCA) patients.

Methods and results

Nationwide historical follow-up study of 41 186 unselected OHCA patients, in whom resuscitation was attempted between 2001 and 2013, identified through the Danish Cardiac Arrest Registry. We observed an increase in the proportion of patients receiving bystander CPR (18% in 2001, 60% in 2013, P < 0.001), achieving return of spontaneous circulation (ROSC) (10% in 2001, 29% in 2013, P < 0.001) and being admitted directly to an invasive centre (26% in 2001, 45% in 2013, P < 0.001). Simultaneously, 30-day survival rose from 5% in 2001 to 12% in 2013, P < 0.001. Among patients achieving ROSC, a larger proportion underwent acute CAG/PCI (5% in 2001, 27% in 2013, P < 0.001). The proportion of patients undergoing acute CAG/PCI annually in each region was defined as the CAG/PCI index. The following variables were associated with lower mortality in multivariable analyses: direct admission to invasive heart centre (HR 0.91, 95% CI: 0.89-0.93), CAG/PCI index (HR 0.33, 95% CI: 0.25-0.45), population density above 2000 per square kilometre (HR 0.94, 95% CI: 0.89-0.98), bystander CPR (HR 0.97, 95% CI: 0.95-0.99) and witnessed OHCA (HR 0.87, 95% CI: 0.85-0.89), whereas distance to the nearest invasive centre was not associated with survival.

Conclusion

Admission to an invasive heart centre and regional performance of acute CAG/PCI were associated with improved survival in OHCA patients, whereas distance to the invasive centre was not. These results support a centralized strategy for immediate post-resuscitation care in OHCA patients.

Out-of-hospital cardiac arrest: in-hospital intervention strategies

The prognosis after out-of-hospital cardiac arrest (OHCA) has improved in the past few decades because of advances in interventions used outside and in hospital. About half of patients who have OHCA with initial ventricular tachycardia or ventricular fibrillation and who are admitted to hospital in coma after return of spontaneous circulation will survive to discharge with a reasonable neurological status. In this Series paper we discuss in-hospital management of patients with post-cardiac-arrest syndrome. In most patients, the most important in-hospital interventions other than routine intensive care are continuous active treatment (in non-comatose and comatose patients and including circulatory support in selected patients), cooling of core temperature to 32-36°C by targeted temperature management for at least 24 h, immediate coronary angiography with or without percutaneous coronary intervention, and delay of final prognosis until at least 72 h after OHCA. Prognosis should be based on clinical observations and multimodal testing, with focus on no residual sedation.

Out-of-hospital cardiac arrest: current concepts

Out-of-hospital cardiac arrest (OHCA) is a leading cause of global mortality. Regional variations in reporting frameworks and survival mean the exact burden of OHCA to public health is unknown. Nevertheless, overall prognosis and neurological outcome are relatively poor following OHCA and have remained almost static for the past three decades. In this Series paper, we explore the aetiology of OHCA. Coronary artery disease remains the predominant cause, but there is a diverse range of other potential cardiac and non-cardiac causes to be aware of. Additionally, we describe how investigators and key stakeholders in resuscitation science have formulated specific Utstein data element domains in an attempt to standardise the definitions and outcomes reported in OHCA research so that management pathways can be improved. Finally, we identify the predictors of survival after OHCA and what primary and secondary prevention strategies can be instigated to mitigate the devastating sequelae of this growing public health issue.

Variation in outcome of hospitalised patients with out-of-hospital cardiac arrest from acute coronary syndrome: a cohort study

Background

Each year, approximately 30,000 people have an out-of-hospital cardiac arrest (OHCA) that is treated by UK ambulance services. Across all cases of OHCA, survival to hospital discharge is less than 10%. Acute coronary syndrome (ACS) is a common cause of OHCA.

Objectives

To explore factors that influence survival in patients who initially survive an OHCA attributable to ACS.

Data source

Data collected by the Myocardial Ischaemia National Audit Project (MINAP) between 2003 and 2015.

Participants

Adult patients who had a first OHCA attributable to ACS and who were successfully resuscitated and admitted to hospital.

Main outcome measures

Hospital mortality, neurological outcome at hospital discharge, and time to all-cause mortality.

Methods

We undertook a cohort study using data from the MINAP registry. MINAP is a national audit that collects data on patients admitted to English, Welsh and Northern Irish hospitals with myocardial ischaemia. From the data set, we identified patients who had an OHCA. We used imputation to address data missingness across the data set. We analysed data using multilevel logistic regression to identify modifiable and non-modifiable factors that affect outcome.

Results

Between 2003 and 2015, 1,127,140 patient cases were included in the MINAP data set. Of these, 17,604 OHCA cases met the study inclusion criteria. Overall hospital survival was 71.3%. Across hospitals with at least 60 cases, hospital survival ranged from 34% to 89% (median 71.4%, interquartile range 60.7–76.9%). Modelling, which adjusted for patient and treatment characteristics, could account for only 36.1% of this variability. For the primary outcome, the key modifiable factors associated with reduced mortality were reperfusion treatment [primary percutaneous coronary intervention (pPCI) or thrombolysis] and admission under a cardiologist. Admission to a high-volume cardiac arrest hospital did not influence survival. Sensitivity analyses showed that reperfusion was associated with reduced mortality among patients with a ST elevation myocardial infarction (STEMI), but there was no evidence of a reduction in mortality in patients who did not present with a STEMI.

Limitations

This was an observational study, such that unmeasured confounders may have influenced study findings. Differences in case identification processes at hospitals may contribute to an ascertainment bias.

Conclusions

In OHCA patients who have had a cardiac arrest attributable to ACS, there is evidence of variability in survival between hospitals, which cannot be fully explained by variables captured in the MINAP data set. Our findings provide some support for the current practice of transferring resuscitated patients with a STEMI to a hospital that can deliver pPCI. In contrast, it may be reasonable to transfer patients without a STEMI to the nearest appropriate hospital.

Future work

There is a need for clinical trials to examine the clinical effectiveness and cost-effectiveness of invasive reperfusion strategies in resuscitated OHCA patients of cardiac cause who have not had a STEMI.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Variations in Cardiac Arrest Regionalization in California

Introduction

The development of cardiac arrest centers and regionalization of systems of care may improve survival of patients with out-of-hospital cardiac arrest (OHCA). This survey of the local EMS agencies (LEMSA) in California was intended to determine current practices regarding the treatment and routing of OHCA patients and the extent to which EMS systems have regionalized OHCA care across California.

Methods

We surveyed all of the 33 LEMSA in California regarding the treatment and routing of OHCA patients according to the current recommendations for OHCA management.

Results

Two counties, representing 29% of the California population, have formally regionalized cardiac arrest care. Twenty of the remaining LEMSA have specific regionalization protocols to direct all OHCA patients with return of spontaneous circulation to designated percutaneous coronary intervention (PCI)-capable hospitals, representing another 36% of the population. There is large variation in LEMSA ability to influence inhospital care. Only 14 agencies (36%), representing 44% of the population, have access to hospital outcome data, including survival to hospital discharge and cerebral performance category scores.

Conclusion

Regionalized care of OHCA is established in two of 33 California LEMSA, providing access to approximately one-third of California residents. Many other LEMSA direct OHCA patients to PCI-capable hospitals for primary PCI and targeted temperature management, but there is limited regional coordination and system quality improvement. Only one-third of LEMSA have access to hospital data for patient outcomes.

Future Directions: Management of Sudden Cardiac Death

There will always be a need to optimize early recognition and treatment of sudden cardiac arrest. For out-of-hospital cardiac arrest, this requires a complex system of care involving bystanders, 911 dispatchers, and emergency medical service and hospital-based providers. Optimizing this system is fundamental to improving outcomes. In addition, personnel and resources are needed to develop and sustain a research pipeline that will bring new scientific discoveries and technologies to the field. The 2015 Institute of Medicine report, "Strategies to Improve Cardiac Arrest Survival: A Time to Act," provides a roadmap.

A Novel Survey Tool to Quantify the Degree and Duration of STEMI Regionalization Across California

INTRODUCTION

California has been a global leader in regionalization efforts for time-critical medical conditions. A total of 33 local emergency medical service agencies (LEMSAs) exist, providing an organized EMS framework across the state for almost 40 years. We sought to develop a survey tool to quantify the degree and duration of ST-elevation myocardial infarction (STEMI) regionalization over the last decade in California.

METHODS

The project started with the development of an 8-question survey tool via a multi-disciplinary expert consensus process. Next, the survey tool was distributed at the annual meeting of administrators and medical directors of California LEMSAs to get responses valid through December, 2014. The first scoring approach was the Total Regionalization Score (TRS) and used answers from all 8 questions. The second approach was called the Core Score, and it focused on only 4 survey questions by assuming that the designation of STEMI Receiving Centers must have occurred at the beginning of any LEMSA's regionalization effort. Scores were ranked and grouped into tertiles.

RESULTS

All 33 LEMSAs in California participated in this survey. The TRS ranged from 15 to 162. The Core Score range was much narrower, from 2 to 30. In comparing TRS and Core Score rankings, the top-tertiles were quite similar. More rank variation occurred between mid- and low-tertiles.

CONCLUSION

This study evaluated the degree and duration of STEMI network regionalization from 2004 to 2014 in California, and ranked 33 LEMSAs into tertiles based upon their TRS and their Core Score. Successful application of the 8-item survey and ranking strategies across California suggests that this approach can be used to assess regionalization in other states or countries around the world.

Improvement in Care and Outcomes for Emergency Medical Service-Transported Patients With ST-Elevation Myocardial Infarction (STEMI) With and Without Prehospital Cardiac Arrest: A Mission: Lifeline STEMI Accelerator Study

BACKGROUND

Patients with ST-elevation myocardial infarction (STEMI) with out-of-hospital cardiac arrest (OHCA) may benefit from direct transport to a percutaneous cardiac intervention (PCI) hospital but have previously been less likely to bypass local non-PCI hospitals to go to a PCI center.

METHODS AND RESULTS

We reported time trends in emergency medical service transport and care of patients with STEMI with and without OHCA included from 171 PCI-capable hospitals in 16 US regions with participation in the Mission: Lifeline STEMI Accelerator program between July 1, 2012, and March 31, 2014. Time trends by quarter were assessed using logistic regression with generalized estimating equations to account for hospital clustering. Of 13 189 emergency medical service-transported patients, 88.7% (N=11 703; 10.5% OHCA) were taken directly to PCI hospitals. Among 1486 transfer-in patients, 21.7% had OHCA. Direct transport to a PCI center for OHCA increased from 74.7% (July 1, 2012) to 83.6% (March 31, 2014) (odds ratio per quarter, 1.07; 95% confidence interval, 1.02-1.14), versus 89.0% to 91.0% for patients without OHCA (odds ratio, 1.03; 95% confidence interval, 0.99-1.07; interaction P=0.23). The proportion with prehospital ECGs increased for patients taken directly to PCI centers (53.9%-61.9% for those with OHCA versus 73.9%-81.9% for those without OHCA; interaction P=0.12). Of 997 patients with OHCA taken directly to PCI hospitals and treated with primary PCI, first medical contact-to-device times within the guideline-recommended goal of ≤90 minutes were met for 34.5% on July 1, 2012, versus 41.8% on March 31, 2014 (51.6% and 56.1%, respectively, for 9352 counterparts without OHCA; interaction P=0.72).

CONCLUSIONS

Direct transport to PCI hospitals increased for patients with STEMI with and without OHCA during the 2012 to 2014 Mission: Lifeline STEMI Accelerator program. Proportions with prehospital ECGs and timely reperfusion increased for patients taken directly to PCI hospitals.

Multistate 5-Year Initiative to Improve Care for Out-of-Hospital Cardiac Arrest: Primary Results From the HeartRescue Project

Background

The HeartRescue Project is a multistate public health initiative focused on establishing statewide out‐of‐hospital cardiac arrest (OHCA) systems of care to improve case capture and OHCA care in the community, by emergency medical services (EMS), and at hospital level.

Methods and Results

From 2011 to 2015 in the 5 original HeartRescue states, all adults with EMS–treated OHCA due to a presumed cardiac cause were included. In an adult population of 32.8 million, a total of 64 988 OHCAs—including 10 046 patients with a bystander‐witnessed OHCA with a shockable rhythm—were treated by 330 EMS agencies. From 2011 to 2015, the case‐capture rate for all‐rhythm OHCA increased from an estimated 39.0% (n=6762) to 89.2% (n=16 103; P<0.001 for trend). Overall survival to hospital discharge was 11.4% for all rhythms and 34.0% in the subgroup with bystander‐witnessed OHCA with a shockable rhythm. We observed modest temporal increases in bystander cardiopulmonary resuscitation (41.8–43.5%, P<0.001 for trend) and bystander automated external defibrillator application (3.2–5.6%, P<0.001 for trend) in the all‐rhythm group, although there were no temporal changes in survival. There were marked all‐rhythm survival differences across the 5 states (8.0–16.1%, P<0.001) and across participating EMS agencies (2.7–26.5%, P<0.001).

Conclusions

In the initial 5 years, the HeartRescue Project developed a population‐based OHCA registry and improved statewide case‐capture rates and some processes of care, although there were no early temporal changes in survival. The observed survival variation across states and EMS systems presents a future challenge to elucidate the characteristics of high‐performing systems with the goal of improving OHCA care and survival.

Contemporary Management of Cardiogenic Shock: A Scientific Statement From the American Heart Association

Cardiogenic shock is a high-acuity, potentially complex, and hemodynamically diverse state of end-organ hypoperfusion that is frequently associated with multisystem organ failure. Despite improving survival in recent years, patient morbidity and mortality remain high, and there are few evidence-based therapeutic interventions known to clearly improve patient outcomes. This scientific statement on cardiogenic shock summarizes the epidemiology, pathophysiology, causes, and outcomes of cardiogenic shock; reviews contemporary best medical, surgical, mechanical circulatory support, and palliative care practices; advocates for the development of regionalized systems of care; and outlines future research priorities.

Challenges of Using Probabilistic Linkage Methodology to Characterize Post-Cardiac Arrest Care in Michigan

BACKGROUND

To improve survival of patients resuscitated from out of hospital cardiac arrest (OCHA), data is needed to assess and improve inpatient post-resuscitation care. Our objective was to apply probabilistic linkage methodology to link EMS and inpatient databases and evaluate whether it may be used to describe post-arrest care in Michigan.

METHODS

We performed a retrospective study to describe post-cardiac arrest care in adult OHCA patients who were transported to Michigan hospitals from July 1, 2010, to June 30, 2013. Using probabilistic linkage methodology we linked two databases, the Michigan EMS Information System (MI_EMSIS) and the Michigan Inpatient Database (MIDB), which describes inpatient care and outcome of all admissions. Rates of case incidence and survival were compared to published literature. We compared the linked dataset to existing cardiac arrest databases from three counties to evaluate the quality of this linkage.

RESULTS

Multiple iterations of match strategies were used to create a linked EMS-inpatient dataset. There were 12,838 MI_EMSIS cardiac arrest records of which 1,977 were matched with MIDB records, identifying them as surviving to hospital admission. Of these 590 (30.0%) survived to hospital discharge. The annual survival incidence/100,000 population to admission was 6.93/100,000 and survival incidence to discharge was 2.1/100,000. The matched dataset was compared to county databases identified a limited sensitivity [48.2%, 95% CI 42.1%-55.3%)] and positive predictive value [64.4%, 95% CI 56.8%-71.3%)].

CONCLUSION

Use of the MI_EMSISEMS database and the Michigan Inpatient database was feasible and produced rates of cardiac arrest admission and survival rates similar to published literature. This process yielded a limited match compared to existing county cardiac arrest databases. We conclude that such a linked dataset is useful for descriptive purposes but not as a population based dataset to evaluate statewide post-cardiac arrest care.

The Postcardiac Arrest Consult Team: Impact on Hospital Care Processes for Out-of-Hospital Cardiac Arrest Patients

OBJECTIVE

To evaluate whether a Post-Arrest Consult Team improved care and outcomes for patients with out-of-hospital cardiac arrest.

DESIGN

Prospective cohort study of Post-Arrest Consult Team implementation at two hospitals, with concurrent controls from 27 others.

SETTING

Twenty-nine hospitals within the Strategies for Post-Arrest Care Network of Southern Ontario, Canada.

PATIENTS

We included comatose adult nontraumatic out-of-hospital cardiac arrest patients surviving more than or equal to 6 hours after emergency department arrival who had no contraindications to targeted temperature management.

INTERVENTION

The Post-Arrest Consult Team was an advisory consult service to improve 1) targeted temperature management, 2) assessment for percutaneous coronary intervention, 3) electrophysiology assessment, and 4) appropriately delayed neuroprognostication.

MEASUREMENTS AND MAIN RESULTS

We used generalized linear mixed models to explore the association between Post-Arrest Consult Team implementation and performance of targeted processes. We included 1,006 patients. The Post-Arrest Consult Team was associated with a significant reduction over time in rates of withdrawal of life-sustaining therapy within 72 hours of emergency department arrival on the basis of predictions of poor neurologic prognosis (ratio of odds ratios, 0.13; 95% CI, 0.02-0.98). Post-Arrest Consult Team was not associated with improved successful targeted temperature management (ratio of odds ratios, 0.91; 95% CI, 0.31-2.65), undergoing angiography (ratio of odds ratios, 1.91; 95% CI, 0.17-21.04), receiving electrophysiology consultation (ratio of odds ratios, 0.93; 95% CI, 0.11-8.16), or functional survival (ratio of odds ratios, 0.75; 95% CI, 0.19-2.94).

CONCLUSIONS

Implementation of a Post-Arrest Consult Team reduced premature withdrawal of life-sustaining therapy but did not improve rates of successful targeted temperature management, coronary angiography, formal electrophysiology assessments, or functional survival for comatose patients after out-of-hospital cardiac arrest.

Cardiopulmonary Resuscitation Training Disparities in the United States

Background

Bystander cardiopulmonary resuscitation (CPR) is associated with increased survival from cardiac arrest, yet bystander CPR rates are low in many communities. The overall prevalence of CPR training in the United States and associated individual‐level disparities are unknown. We sought to measure the national prevalence of CPR training and hypothesized that older age and lower socioeconomic status would be independently associated with a lower likelihood of CPR training.

Methods and Results

We administered a cross‐sectional telephone survey to a nationally representative adult sample. We assessed the demographics of individuals trained in CPR within 2 years (currently trained) and those who had been trained in CPR at some point in time (ever trained). The association of CPR training and demographic variables were tested using survey weighted logistic regression. Between September 2015 and November 2015, 9022 individuals completed the survey; 18% reported being currently trained in CPR, and 65% reported training at some point previously. For each year of increased age, the likelihood of being currently CPR trained or ever trained decreased (currently trained: odds ratio, 0.98; 95% CI, 0.97–0.99; P<0.01; ever trained: OR, 0.99; 95% CI, 0.98–0.99; P=0.04). Furthermore, there was a greater then 4‐fold difference in odds of being currently CPR trained from the 30–39 to 70–79 year old age groups (95% CI, 0.10–0.23). Factors associated with a lower likelihood of CPR training were lesser educational attainment and lower household income (P<0.01 for each of these variables).

Conclusions

A minority of respondents reported current training in CPR. Older age, lesser education, and lower income were associated with reduced likelihood of CPR training. These findings illustrate important gaps in US CPR education and suggest the need to develop tailored CPR training efforts to address this variability.

Impact of mobile intensive care unit use on total ischemic time and clinical outcomes in ST-elevation myocardial infarction patients - real-world data from the Acute Coronary Syndrome Israeli Survey

BACKGROUND

Ischemic time has prognostic importance in ST-elevation myocardial infarction patients. Mobile intensive care unit use can reduce components of total ischemic time by appropriate triage of ST-elevation myocardial infarction patients.

METHODS

Data from the Acute Coronary Survey in Israel registry 2000-2010 were analyzed to evaluate factors associated with mobile intensive care unit use and its impact on total ischemic time and patient outcomes.

RESULTS

The study comprised 5474 ST-elevation myocardial infarction patients enrolled in the Acute Coronary Survey in Israel registry, of whom 46% ( n=2538) arrived via mobile intensive care units. There was a significant increase in rates of mobile intensive care unit utilization from 36% in 2000 to over 50% in 2010 ( p<0.001). Independent predictors of mobile intensive care unit use were Killip>1 (odds ratio=1.32, p<0.001), the presence of cardiac arrest (odds ratio=1.44, p=0.02), and a systolic blood pressure <100 mm Hg (odds ratio=2.01, p<0.001) at presentation. Patients arriving via mobile intensive care units benefitted from increased rates of primary reperfusion therapy (odds ratio=1.58, p<0.001). Among ST-elevation myocardial infarction patients undergoing primary reperfusion, those arriving by mobile intensive care unit benefitted from shorter median total ischemic time compared with non-mobile intensive care unit patients (175 (interquartile range 120-262) vs 195 (interquartile range 130-333) min, respectively ( p<0.001)). Upon a multivariate analysis, mobile intensive care unit use was the most important predictor in achieving door-to-balloon time <90 min (odds ratio=2.56, p<0.001) and door-to-needle time <30 min (odds ratio=2.96, p<0.001). One-year mortality rates were 10.7% in both groups (log-rank p-value=0.98), however inverse propensity weight model, adjusted for significant differences between both groups, revealed a significant reduction in one-year mortality in favor of the mobile intensive care unit group (odds ratio=0.79, 95% confidence interval (0.66-0.94), p=0.01).

CONCLUSIONS

Among patients with ST-elevation myocardial infarction, the utilization of mobile intensive care units is associated with increased rates of primary reperfusion, a reduction in the time interval to reperfusion, and a reduction in one-year adjusted mortality.

Rosuvastatin improves myocardial and neurological outcomes after asphyxial cardiac arrest and cardiopulmonary resuscitation in rats

Rosuvastatin, a potent HMG-CoA reductase inhibitor, is cholesterol-lowering drugs and reduce the risk of myocardial infarction and stroke. This study is to explore whether rosuvastatin improves outcomes after cardiac arrest in rats. Male Sprague-Dawley rats were subjected to 8min of cardiac arrest (CA) by asphyxia and randomly assigned to three experimental groups immediately following successful resuscitation: Sham; Control; and Rosuvastatin. The survival, hemodynamics, myocardial function, neurological outcomes and apoptosis were assessed. The 7-d survival rate was greater in the rosuvastatin treated group compared to the Control group (P=0.019 by log-rank test). Myocardial function, as measured by cardiac output and ejection fraction, was significantly impaired after CA and notably improved in the animals treated with rosuvastatin beginning at 60min after return of spontaneous circulation (ROSC) (P<0.05). Moreover, rosuvastatin treatment significantly ameliorated brain injury after ROSC, which was characterized by the increase of neurological function scores, and reduction of brain edema in cortex and hippocampus (P<0.05). Meanwhile, the levels of cardiac troponin T and neuron-specific enolase and the caspase-3 activity were significantly decreased in the Rosuvastatin group when compared with the Control group (P<0.05). In conclusion, rosuvastatin treatment substantially improves the 7-d survival rate as well as myocardial function and neurological outcomes after ROSC.

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

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

The effect of high-risk ST elevation myocardial infarction transfer patients on risk-adjusted in-hospital mortality: A report from the American Heart Association Mission: Lifeline program

BACKGROUND

Hospital mortality is an important quality measure for acute myocardial infarction care. There is a concern that despite risk adjustment, percutaneous coronary intervention hospitals accepting a greater volume of high-risk ST elevation myocardial infarction (STEMI) transfer patients may have their reported mortality rates adversely affected.

METHODS

The STEMI patients in the National Cardiovascular Data RegistryAcute Coronary Treatment Intervention Outcomes Network Registry-Get With the Guidelines from April 2011 to December 2013 were included. High-risk STEMI was defined as having either cardiogenic shock or cardiac arrest on first medical contact. Receiving hospitals were divided into tertiles based on the ratio of high-risk STEMI transfer patients to the total number of STEMI patients treated at each hospital. Using the Action Coronary Treatment Intervention Outcomes Network Registry-Get With the Guidelines in-hospital mortality risk model, we calculated the difference in risk-standardized in-hospital mortality before and after excluding high-risk STEMI transfers in each tertile.

RESULTS

Among 119,680 STEMI patients treated at 539 receiving hospitals, 37,028 (31%) were transfer patients, of whom 4,500 (12%) were highrisk. The proportion of high-risk STEMI transfer patients ranged from 0% to 12% across hospitals. Unadjusted mortality rates in the low-, middle-, and high-tertile hospitals were 6.0%, 6.0%, and 5.9% among all STEMI patients and 6.0%, 5.5%, and 4.6% after excluding high-risk STEMI transfers. However, risk-standardized hospital mortality rates were not significantly changed after excluding high-risk STEMI transfer patients in any of the 3 hospital tertiles (low, -0.04%; middle, -0.05%; and high, 0.03%).

CONCLUSIONS

Risk-adjusted in-hospital mortality rates were not adversely affected in STEMI-receiving hospitals who accepted more high-risk STEMI transfer patients when a clinical mortality risk model was used for risk adjustment.

Controversies in Out of Hospital Cardiac Arrest?

Cardiac arrest is a major cause of morbidity and mortality and accounts for nearly 500,000 deaths annually in the United States. In patients suffering out-of-hospital cardiac arrest, survival is less than 15%, with considerable regional variation. Although most deaths occur during the initial resuscitation, an increasing proportion occur in patients hospitalized after initially successful resuscitation. In these patients, the significant subsequent morbidity and mortality is due to "post cardiac arrest syndrome." Until recently, most single interventions have yielded little improvement in rates of survival; however, there is growing recognition that optimal treatment strategies during the postresuscitation phase may improve outcomes.

The impact of hospital experience with out-of-hospital cardiac arrest patients on post cardiac arrest care

OBJECTIVE

Patient volume as a surrogate for institutional experience has been associated with quality of care indicators for a variety of illnesses. We evaluated the association between hospital experience with comatose out-of-hospital cardiac arrest (OHCA) patients and important care processes.

METHODS

This was a population-based, retrospective cohort study using data from 37 hospitals in Southern Ontario from 2007 to 2013. We included adults with atraumatic OHCA who were comatose on emergency department arrival and survived at least 6h. We excluded patients with a Do-Not-Resuscitate order or severe bleeding within 6h of hospital arrival. Multi-level logistic regression models estimated the association between average annual hospital volume of OHCA patients and outcomes. The primary outcome was successful targeted temperature management (TTM) and secondary outcomes included TTM initiation, premature withdrawal of life-sustaining therapy, and survival with good neurologic function.

RESULTS

Our analysis included 2723 patients. For every increase of 10 in the average annual volume of eligible patients, the adjusted odds increased by 30% for successful TTM (OR 1.29, 95% CI 1.03-1.62) and by 38% for initiating TTM (OR 1.38, 95% CI 1.11-1.72). No significant association between patient volume and other secondary outcomes was observed.

CONCLUSIONS

Patients arriving at hospitals with more experience treating comatose post cardiac arrest patients are more likely to have TTM initiated and to successfully reach target temperature. Our findings have implications for regional systems of care and knowledge translation efforts aiming to improve quality of care for this patient population.

Long-term survival benefit from treatment at a specialty center after cardiac arrest

INTRODUCTION

The Institute of Medicine and American Heart Association have called for tiered accreditation standards and regionalization of post-cardiac arrest care, but there is little data to support that regionalization has a durable effect on patient outcomes. We tested the effect of treatment at a high-volume center on long-term outcome after sudden cardiac arrest (SCA).

METHODS

We included patients hospitalized at one of 7 medical centers in Southwestern Pennsylvania after SCA from 2005 to 2013. Centers were one regional referral center with an organized systems for post-SCA care, two moderate volume tertiary care centers and 4 low-volume centers. We abstracted clinical characteristics and outcomes at hospital discharge, and for survivors to discharge we queried the National Death Index for long-term survival data. We used Cox regression to determine the unadjusted associations of baseline predictors and survival, and built an adjusted model controlling for baseline predictors.

RESULTS

Overall, 987 patients survived to discharge. During 2196 person-years of follow-up, median survival was 5.3 years and there were 396 deaths. In unadjusted analysis, treating center, age, arrest location, Charlson Comorbidity Index, initial rhythm, cardiac catheterization, defibrillator placement, discharge disposition, and neurological status at discharge were associated with long-term outcome. In adjusted analysis, treatment at the high-volume cardiac arrest center was associated with improved survival compared to treatment at other centers (hazards ratio 1.49, 95% confidence interval 1.19-1.86).

CONCLUSION

Treatment at a high-volume cardiac arrest center with organized systems for post-arrest care is associated with a substantial long-term survival benefit after hospital discharge.

Implementation of a post-arrest care team: understanding the nuances of a team-based intervention

Background

Despite advances in the management of sudden cardiac arrest, mortality for patients admitted to hospital is still greater than 50 %. Lack of familiarity and experience with post-cardiac arrest patients and lack of interdisciplinary collaboration between emergency and ICU staff have been highlighted as potential barriers to optimal care. To address these barriers, a specialized Post Arrest Consult Team (PACT) was implemented at two urban academic centers.

Our objective was to describe the PACT implementation from the participant perspective in order to explore potentially mitigating factors on effectiveness of the intervention and inform other institutions who may be considering a similar approach.

Methods

Using an ethnographic style approach, we collected data throughout the implementation period using both key informant interviews and non-participant observation. The data were analyzed using interpretive descriptive analysis techniques.

Results

The PACT intervention was taken up differently in each of the two participating institutions. Participants spoke about the difficulty in maintaining a dynamic interaction between the team members and a shared sense of purpose, the challenge of off-service consulting and the impact of the lack of data feedback to support whether the project was effecting change.

Conclusions

It appears that purposefully creating a “sense of team,” the team composition and organizational culture and provision of performance feedback are important facilitators to ensuring uptake of a team-based intervention like the PACT model. Reporting of the intervention design and actual implementation experience like we have done here is crucial to allow readers to judge the quality of the study, to properly replicate it, and to contemplate how various factors may influence the outcome of a complex intervention.

Glibenclamide Is Comparable to Target Temperature Management in Improving Survival and Neurological Outcome After Asphyxial Cardiac Arrest in Rats

Background

We previously have shown that glibenclamide (GBC), a sulfonylurea receptor 1–transient receptor potential M4 (SUR1‐TRPM4) channel inhibitor, improves survival and neurological outcome after asphyxial cardiac arrest and cardiopulmonary resuscitation (ACA/CPR). Here, we further compare the efficacy of GBC with target temperature management (TTM) and determine whether the efficacy of GBC is affected by TTM.

Methods and Results

Male Sprague‐Dawley rats (n=213) subjected to 10‐minute ACA/CPR were randomized to 4 groups after return of spontaneous circulation (ROSC): normothermia control (NT); GBC; TTM; and TTM+GBC. Survival, neurodeficit scores, histological injury, as well as the expressions of SUR1 and TRPM4 were evaluated. The 7‐day survival rate was 34.4% (11 of 32) in the NT group, 65% (13 of 20) in the GBC group, 50% (10 of 20) in the TTM group, and 70% (14 of 20) in the TTM+GBC group. Rats that received either GBC, TTM alone, or in combination showed less neurological deficit than NT control at 24, 48, and 72 hours and 7 days after ROSC. Moreover, TTM or GBC ameliorated neuronal degeneration and glial activation in the hippocampal CA1 region with similar efficacy, whereas the combination of them had a trend toward better effect. The subunits of SUR1‐TRPM4 heterodimers were both strongly upregulated after ACA/CPR and expressed in multiple types of brain cells, but partly suppressed by TTM.

Conclusions

GBC is comparable to TTM in improving survival and neurological outcome after ACA/CPR. When GBC is given along with TTM, less histological injury tended to be achieved.

Early Coronary Angiography and Survival After Out-of-Hospital Cardiac Arrest

BACKGROUND

Although out-of-hospital cardiac arrest is common because of acute myocardial infarction, it is unknown whether early coronary angiography is associated with improved survival in these patients.

METHODS AND RESULTS

Using data from the Cardiac Arrest Registry to Enhance Survival (CARES), we identified 4029 adult patients admitted to 374 hospitals after successful resuscitation from out-of-hospital cardiac arrest because of ventricular fibrillation, pulseless ventricular tachycardia, or unknown shockable rhythm between January 2010 and December 2013. Early coronary angiography (occurring within one calendar day of cardiac arrest) was performed in 1953 (48.5%) patients, of whom 1253 (64.2%) received coronary revascularization. Patients who underwent early coronary angiography were younger (59.9 versus 62.0 years); more likely to be men (78.1% versus 64.3%), have a witnessed arrest (84.6% versus 77.4%), and have ST-segment-elevation myocardial infarction (32.7% versus 7.9%); and less likely to have known cardiovascular disease (22.8% versus 35.0%), diabetes mellitus (11.0% versus 17.0%), and renal disease (1.8% versus 5.8%; P<0.01 for all comparisons). In analysis of 1312 propensity score-matched pairs, early coronary angiography was associated with higher odds of survival to discharge (odds ratio 1.52 [95% confidence interval 1.28-1.80]; P<0.0001) and survival with favorable neurological outcome (odds ratio 1.47 [95% confidence interval 1.25-1.71]; P<0.0001). Further adjustment for coronary revascularization in our models significantly attenuated both odds ratios, suggesting that revascularization was a key mediator of the survival benefit.

CONCLUSIONS

Among initial survivors of out-of-hospital cardiac arrest caused by VF or pulseless VT, we found early coronary angiography was associated with higher odds of survival to discharge and favorable neurological outcome.

Disparities in Survival with Bystander CPR following Cardiopulmonary Arrest Based on Neighborhood Characteristics

The American Heart Association reports the annual incidence of out-of-hospital cardiopulmonary arrests (OHCA) is greater than 300,000 with a survival rate of 9.5%. Bystander cardiopulmonary resuscitation (CPR) saves one life for every 30, with a 10% decrease in survival associated with every minute of delay in CPR initiation. Bystander CPR and training vary widely by region. We conducted a retrospective study of 320 persons who suffered OHCA in South Florida over 25 months. Increased survival, overall and with bystander CPR, was seen with increasing income (p = 0.05), with a stronger disparity between low- and high-income neighborhoods (p = 0.01 and p = 0.03, resp.). Survival with bystander CPR was statistically greater in white- versus black-predominant neighborhoods (p = 0.04). Increased survival, overall and with bystander CPR, was seen with high- versus low-education neighborhoods (p = 0.03). Neighborhoods with more high school age persons displayed the lowest survival. We discovered a significant disparity in OHCA survival within neighborhoods of low-income, black-predominance, and low-education. Reduced survival was seen in neighborhoods with larger populations of high school students. This group is a potential target for training, and instruction can conceivably change survival outcomes in these neighborhoods, closing the gap, thus improving survival for all.

Implementation of Pit Crew Approach and Cardiopulmonary Resuscitation Metrics for Out-of-Hospital Cardiac Arrest Improves Patient Survival and Neurological Outcome

Introduction

Survival from out‐of‐hospital cardiac arrest (OHCA) varies by community and emergency medical services (EMS) system. We hypothesized that the adoption of multiple best practices to focus EMS crews on high‐quality, minimally interrupted cardiopulmonary resuscitation (CPR) would improve survival of OHCA patients in Salt Lake City.

Methods and Results

In September 2011, Salt Lake City Fire Department EMS providers underwent a systemwide restructuring of care for OHCA patients that focused on the adoption of high‐quality CPR with minimal interruptions and offline medical review of defibrillator data and feedback on CPR metrics. Victims were directed to ST‐elevation myocardial infarction receiving centers. Prospectively collected data on patient survival and neurological outcome for all OHCAs were compared. In the postintervention period, there were 407 cardiac arrests with 65 neurologically intact survivors (16%), compared with 330 cardiac arrests with 25 neurologically intact survivors (8%) in the preintervention period. Among patients who survived to hospital admission, a higher proportion in the postintervention period survived to hospital discharge (71/141 [50%] versus 36/98 [37%], P=0.037) and had a favorable neurological outcome (65 [46%] versus 25 [26%], P=0.0005) compared with patients treated before the protocol changes. The univariate odds ratio or the association between neurologically intact survival (cerebral performance category 1 and 2) and protocol implementation was 2.3 (95% CI 1.4 to 3.7, P=0.001). Among discharged patients, the distribution of cerebral performance category scores was more favorable in the postintervention period (P<0.0001).

Conclusions

A multifaceted protocol, including several American Heart Assocation best practices for the resuscitation of patients with OHCA, was associated with improved survival and neurological outcome.

Prehospital transportation to therapeutic hypothermia centers and survival from out-of-hospital cardiac arrest

Background

Clinical trials supporting the use of therapeutic hypothermia (TH) in the treatment of out-of-hospital cardiac arrest (OHCA) are based on small patient samples and do not reflect the wide variation in patient selection, cooling methods, and other elements of post-arrest care that are used in everyday practice. This study provides a real world evaluation of the effectiveness of post-arrest care in TH centers during a time of growing TH dissemination in the state of New Jersey (NJ).

Methods

Using a linked database of prehospital, hospital, and mortality records for NJ in 2009-2010, we compared rates of neurologically intact survival at discharge and at 30 days for OHCA patients transported to TH centers (N = 2363) versus other hospitals (N = 2479). We used logistic regression to adjust for patient and hospital covariates. To account for potential endogeneity in prehospital transportation decisions, we used an instrumental variable (IV) based on differential distance to the nearest TH and non-TH hospitals.

Results

Patients taken to TH centers were older, more likely to have a witnessed arrest, more likely to receive defibrillation, and waited a shorter amount of time for initial EMS response. Also, TH hospitals were larger, more likely to be teaching facilities, and operated in a service area with a relatively lower poverty rate compared to hospitals statewide. A Stock-Yogo test confirmed the strength of our IV (F = 2349.91, p < 0.0001). Nevertheless, the data showed no evidence of endogenous transportation to TH centers related to in-hospital survival (Z = -0.08, p = 0.934) or 30-day survival (Z = 0.94, p = 0.349). In logistic regression models, treatment at a TH center was associated with greater odds of 30-day neurologically intact survival (OR = 1.70; 95 % CI: 1.19 – 2.42) but not associated with the odds of neurologically intact survival to hospital discharge (OR = 0.90; 95 % CI: 0.61 – 1.31).

Conclusions

Post-arrest outcomes are more favorable at TH centers but these improved outcomes are not apparent until after hospital discharge. This finding may reflect superior care by TH centers in later stages of post-arrest treatment such as care provided in the intensive care unit, which has greater potential to affect longer term outcomes than initial treatment in the emergency department.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-015-1199-z) contains supplementary material, which is available to authorized users.

Post-resuscitation care following out-of-hospital and in-hospital cardiac arrest

Cardiac arrest is a leading cause of death in developed countries. Although a majority of cardiac arrest patients die during the acute event, a substantial proportion of cardiac arrest deaths occur in patients following successful resuscitation and can be attributed to the development of post-cardiac arrest syndrome. There is growing recognition that integrated post-resuscitation care, which encompasses targeted temperature management (TTM), early coronary angiography and comprehensive critical care, can improve patient outcomes. TTM has been shown to improve survival and neurological outcome in patients who remain comatose especially following out-of-hospital cardiac arrest due to ventricular arrhythmias. Early coronary angiography and revascularisation if needed may also be beneficial during the post-resuscitation phase, based on data from observational studies. In addition, resuscitated patients usually require intensive care, which includes mechanical ventilator, haemodynamic support and close monitoring of blood gases, glucose, electrolytes, seizures and other disease-specific intervention. Efforts should be taken to avoid premature withdrawal of life-supporting treatment, especially in patients treated with TTM. Given that resources and personnel needed to provide high-quality post-resuscitation care may not exist at all hospitals, professional societies have recommended regionalisation of post-resuscitation care in specialised 'cardiac arrest centres' as a strategy to improve cardiac arrest outcomes. Finally, evidence for post-resuscitation care following in-hospital cardiac arrest is largely extrapolated from studies in patients with out-of-hospital cardiac arrest. Future studies need to examine the effectiveness of different post-resuscitation strategies, such as TTM, in patients with in-hospital cardiac arrest.