A systematic review and meta-analysis of the effect of routine early angiography in patients with return of spontaneous circulation after Out-of-Hospital Cardiac Arrest

Association Between the Timing of Coronary Angiography, Targeted Temperature Management, and Neurological Outcomes After Out-of-Hospital Cardiac Arrest: A Nationwide Population-Based Registry Study in Korea

BACKGROUND

Coronary angiography (CAG) and targeted temperature management (TTM) may improve clinical outcomes after out-of-hospital cardiac arrest. This study aimed to assess whether the intervention effects differed according to timing and percutaneous coronary intervention (PCI) performance.

METHODS AND RESULTS

Adult patients with presumed cardiac cause who underwent CAG and TTM within 24 hours following out-of-hospital cardiac arrest were included from the Korean nationwide out-of-hospital cardiac arrest registry. We investigated the associations between the timing of interventions and whether CAG was performed before TTM initiation (CAG-first) and good neurological outcomes. Intervention times were divided into 4 quartiles, and odds ratios (ORs) were calculated with the fourth quartile as the reference. A total of 844 patients were enrolled. CAG and TTM were initiated a median of 2.4 hours (interquartile range [IQR], 1.8-3.2) and 4.3 hours (IQR, 3.2-6.0) after OHCA, respectively. Univariable analysis revealed associations between the earliest intervention groups and good neurological outcomes. However, after adjustment, neither the intervention time nor intervention prioritization was associated with good outcomes. The first quartile of CAG time (<1.8 hours) was associated with good outcomes in the subgroup with PCI (n=570) (adjusted OR [aOR], 1.93 [95% CI, 1.10-3.40]). In the subgroup without PCI (n=274), early TTM initiation (<3.2 hours) and CAG-first were significantly associated with outcomes (aOR, 3.08 [95% CI, 1.36-6.96]; aOR, 0.44 [95% CI, 0.20-0.97]; respectively).

CONCLUSIONS

Neither intervention time nor intervention prioritization was associated with good outcomes. However, early CAG and TTM independently predicted good outcomes in the subgroups with PCI and without PCI, respectively.

Cardiac Arrest and Cardiopulmonary Resuscitation Outcome Reports: 2024 Update of the Utstein Out-of-Hospital Cardiac Arrest Registry Template

The Utstein Out-of-Hospital Cardiac Arrest Resuscitation Registry Template, introduced in 1991 and updated in 2004 and 2015, standardizes data collection to enable research, evaluation, and comparisons of systems of care. The impetus for the current update stemmed from significant advances in the field and insights from registry development and regional comparisons. This 2024 update involved representatives of the International Liaison Committee on Resuscitation and used a modified Delphi process. Every 2015 Utstein data element was reviewed for relevance, priority (core or supplemental), and improvement. New variables were proposed and refined. All changes were voted on for inclusion. The 2015 domains-system, dispatch, patient, process, and outcomes-were retained. Further clarity is provided for the definitions of out-of-hospital cardiac arrest attended resuscitation and attempted resuscitation. Changes reflect advancements in dispatch, early response systems, and resuscitation care, as well as the importance of prehospital outcomes. Time intervals such as emergency medical service response time now emphasize precise reporting of the times used. New flowcharts aid the reporting of system effectiveness for patients with an attempted resuscitation and system efficacy for the Utstein comparator group. Recognizing the varying capacities of emergency systems globally, the writing group provided a minimal dataset for settings with developing emergency medical systems. Supplementary variables are considered useful for research purposes. These revisions aim to elevate data collection and reporting transparency by registries and researchers and to advance international comparisons and collaborations. The overarching objective remains the improvement of outcomes for patients with out-of-hospital cardiac arrest.

Cardiac arrest and cardiopulmonary resuscitation outcome reports: 2024 update of the Utstein Out-of-Hospital Cardiac Arrest Registry template

The Utstein Out-of-Hospital Cardiac Arrest Resuscitation Registry Template, introduced in 1991 and updated in 2004 and 2015, standardizes data collection to enable research, evaluation, and comparisons of systems of care. The impetus for the current update stemmed from significant advances in the field and insights from registry development and regional comparisons. This 2024 update involved representatives of the International Liaison Committee on Resuscitation and used a modified Delphi process. Every 2015 Utstein data element was reviewed for relevance, priority (core or supplemental), and improvement. New variables were proposed and refined. All changes were voted on for inclusion. The 2015 domains-system, dispatch, patient, process, and outcomes-were retained. Further clarity is provided for the definitions of out-of-hospital cardiac arrest attended resuscitation and attempted resuscitation. Changes reflect advancements in dispatch, early response systems, and resuscitation care, as well as the importance of prehospital outcomes. Time intervals such as emergency medical service response time now emphasize precise reporting of the times used. New flowcharts aid the reporting of system effectiveness for patients with an attempted resuscitation and system efficacy for the Utstein comparator group. Recognizing the varying capacities of emergency systems globally, the writing group provided a minimal dataset for settings with developing emergency medical systems. Supplementary variables are considered useful for research purposes. These revisions aim to elevate data collection and reporting transparency by registries and researchers and to advance international comparisons and collaborations. The overarching objective remains the improvement of outcomes for patients with out-of-hospital cardiac arrest.

Randomized controlled trials in resuscitation

Randomized controlled trials (RCTs) are a gold standard in research and crucial to our understanding of resuscitation science. Many trials in resuscitation have had neutral findings, questioning which treatments are effective in cardiac resuscitation. While it is possible than many interventions do not improve patient outcomes, it is also possible that the large proportion of neutral findings are partially due to design limitations. RCTs can be challenging to implement, and require extensive resources, time, and funding. In addition, conducting RCTs in the out-of-hospital setting provides unique challenges that must be considered for a successful trial. This article will outline many important aspects of conducting trials in resuscitation in the out-of-hospital setting including patient and outcome selection, trial design, and statistical analysis.

Post-Cardiac Arrest Syndrome

Post-cardiac arrest syndrome (PCAS) is a multicomponent entity affecting many who survive an initial period of resuscitation following cardiac arrest. This focussed review explores some of the strategies for mitigating the effects of PCAS following the return of spontaneous circulation. We consider the current evidence for controlled oxygenation, strategies for blood-pressure targets, the timing of coronary reperfusion, and the evidence for temperature control and treatment of seizures. Despite several large trials investigating specific strategies to improve outcomes after cardiac arrest, many questions remain unanswered. Results of some studies suggest that interventions may benefit specific subgroups of cardiac arrest patients, but the optimal timing and duration of many interventions remain unknown. The role of intracranial pressure monitoring has been the subject of only a few studies, and its benefits remain unclear. Research aimed at improving the management of PCAS is ongoing.

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.

2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimising pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

Impact of emergent coronary angiography after out-of-the-hospital cardiac arrest without ST-segment elevation - a systematic review and meta-analysis

INTRODUCTION

Coronary artery disease is a leading cause of out-of-the-hospital cardiac arrest (OHCA). However, there is no consensus on whether OHCA patients without ST-segment elevation (STE) benefit from emergent (ie < 2 h) coronary angiography (CAG). Our aim was to assess the impact of emergent CAG in no-STE OHCA patients.

METHODS

We performed a systematic review and meta-analysis by searching the MEDLINE, Cochrane, Scopus, CINAHL and JBI databases for randomized controlled trials (RCTs) comparing emergent CAG versus standard of care (ie CAG >2 h after OHCA or not performed) in no-STE OHCA patients of presumed cardiac aetiology. The primary outcome was short term survival. Secondary outcomes included survival with good neurological outcome, mid-term survival, left ventricle ejection fraction (LVEF), acute kidney injury (AKI) and renal replacement therapy (RRT), ventricular arrhythmias and major bleeding during hospital stay.

RESULTS

Seven RCTs met the inclusion and exclusion criteria and were included; one was included only in the analysis of mid-term survival and another in the LVEF analysis. Five studies (1278 patients, 643 with early CAG and 635 with no early CAG) were included in the analysis of the primary endpoint. The groups were balanced for all baseline characteristics but previous PCI, which was more frequent in the standard of care groups. There were no significant differences between groups for short-term survival (57 vs 61%; OR0.85, 95% CI0.68-1.07; I² = 0%). There were also no differences for any of the secondary endpoints.

CONCLUSION

Routine emergent CAG did not improve survival in comatose survivors of OHCA with shockable rhythm and no-STE.

Resuscitation guideline highlights

PURPOSE OF REVIEW

The purpose of this review was to give an overview of the most significant updates in resuscitation guidelines and provide some insights into the new topics being considered in upcoming reviews.

RECENT FINDINGS

Recent updates to resuscitation guidelines have highlighted the importance of the earlier links in the chain-of-survival aimed to improve early recognition, early cardiopulmonary resuscitation (CPR) and defibrillation. Empowering lay rescuers with the support of emergency medical dispatchers or telecommunicators and engaging the community through dispatching volunteers and Automated External Defibrillators, are considered key in improving cardiac arrest outcomes. Novel CPR strategies such as passive insufflation and head-up CPR are being explored, but lack high-certainty evidence. Increased focus on survivorship also highlights the need for more evidence based guidance on how to facilitate the necessary follow-up and rehabilitation after cardiac arrest. Many of the systematic and scoping reviews performed within cardiac arrest resuscitation domains identifies significant knowledge gaps on key elements of our resuscitation practices. There is an urgent need to address these gaps to further improve survival from cardiac arrest in all settings.

SUMMARY

A continuous evidence evaluation process for resuscitation after cardiac arrest is triggered by new evidence or request by the resuscitation community, and provides more current and relevant guidance for clinicians.

Clinical factors associated with significant coronary lesions following out-of-hospital cardiac arrest

OBJECTIVES

Out-of-hospital cardiac arrest (OHCA) afflicts >350,000 people annually in the United States. While postarrest coronary angiography (CAG) with percutaneous coronary intervention (PCI) has been associated with improved survival in observational cohorts, substantial uncertainty exists regarding patient selection for postarrest CAG. We tested the hypothesis that symptoms consistent with acute coronary syndrome (ACS), including chest discomfort, prior to OHCAs are associated with significant coronary lesions identified on postarrest CAG.

METHODS

We conducted a multicenter retrospective cohort study among eight regional hospitals. Adult patients who experienced atraumatic OHCA with successful initial resuscitation and subsequent CAG between January 2015 and December 2019 were included. We collected data on prehospital documentation of potential ACS symptoms prior to OHCA as well as clinical factors readily available during postarrest care. The primary outcome in multivariable regression modeling was the presence of significant coronary lesions (defined as >50% stenosis of left main or >75% stenosis of other coronary arteries).

RESULTS

Four-hundred patients were included. Median (interquartile range) age was 59 (51-69) years; 31% were female. At least one significant stenosis was found in 62%, of whom 71% received PCI. Clinical factors independently associated with a significant lesion included a history of myocardial infarction (adjusted odds ratio [aOR] = 6.5, [95% confidence interval {CI} = 1.3 to 32.4], p = 0.02), prearrest chest discomfort (aOR = 4.8 [95% CI = 2.1 to 11.8], p ≤ 0.001), ST-segment elevations (aOR = 3.2 [95% CI = 1.7 to 6.3], p < 0.001), and an initial shockable rhythm (aOR = 1.9 [95% CI = 1.0 to 3.4], p = 0.05).

CONCLUSIONS

Among survivors of OHCA receiving CAG, history of prearrest chest discomfort was significantly and independently associated with significant coronary artery lesions on postarrest CAG. This suggests that we may be able to use prearrest symptoms to better risk stratify patients following OHCA to decide who will benefit from invasive angiography.

Coronary angiography and percutaneous coronary intervention in cardiac arrest patients without return of spontaneous circulation

OBJECTIVES

This study aimed to examine coronary angiography (CAG) findings, percutaneous coronary intervention (PCI) results and outcomes in out-of-hospital cardiac arrest patients (OHCA) without return of spontaneous circulation (ROSC) on admission to hospital.

METHODS

We analyzed the OHCA register and compared CAG, PCI, and outcome data in patients with and without ROSC on admission to hospital.

RESULTS

Between January 2012 and December 2020, 697 OHCA patients were analyzed. Of these, 163 (23%) did not have ROSC at admission. Patients without ROSC were younger (59 vs. 61 years, p=0.001) and had a longer resuscitation time (62 vs. 18 minutes, p<0.001) than patients with ROSC. Significant coronary artery disease was highly prevalent in both groups (65% vs. 68%, p=0.48). Patients without ROSC had higher rates of acute coronary occlusions (42% vs. 33%, p=0.046), specifically affecting the left main stem (16% vs. 1%, p<0.001). PCI was performed in 81 patients (50%) without ROSC and in 295 (55%) with ROSC (p=0.21). The success rate was 86% in patients without ROSC and 90% in patients with ROSC (p=0.33). Thirty-day survival was 24% in patients without ROSC and 70% in patients with ROSC.

CONCLUSIONS

OHCA patients without ROSC on admission to hospital had higher acute coronary occlusion rates than patients with prehospital ROSC. PCI is feasible with a high success rate in patients without ROSC. Despite prolonged resuscitation times, meaningful survival in patients admitted without ROSC is achievable.

Advanced Life Support Update

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2022. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2022 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from https://link.springer.com/bookseries/8901 .

Impact of Cardiac Arrest Centers on the Survival of Patients With Nontraumatic Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

Background

The role of cardiac arrest centers (CACs) in out‐of‐hospital cardiac arrest care systems is continuously evolving. Interpretation of existing literature is limited by heterogeneity in CAC characteristics and types of patients transported to CACs. This study assesses the impact of CACs on survival in out‐of‐hospital cardiac arrest according to varying definitions of CAC and prespecified subgroups.

Methods and Results

Electronic databases were searched from inception to March 9, 2021 for relevant studies. Centers were considered CACs if self‐declared by study authors and capable of relevant interventions. Main outcomes were survival and neurologically favorable survival at hospital discharge or 30 days. Meta‐analyses were performed for adjusted odds ratio (aOR) and crude odds ratios. Thirty‐six studies were analyzed. Survival with favorable neurological outcome significantly improved with treatment at CACs (aOR, 1.85 [95% CI, 1.52–2.26]), even when including high‐volume centers (aOR, 1.50 [95% CI, 1.18–1.91]) or including improved‐care centers (aOR, 2.13 [95% CI, 1.75–2.59]) as CACs. Survival significantly increased with treatment at CACs (aOR, 1.92 [95% CI, 1.59–2.32]), even when including high‐volume centers (aOR, 1.74 [95% CI, 1.38–2.18]) or when including improved‐care centers (aOR, 1.97 [95% CI, 1.71–2.26]) as CACs. The treatment effect was more pronounced among patients with shockable rhythm (P=0.006) and without prehospital return of spontaneous circulation (P=0.005). Conclusions were robust to sensitivity analyses, with no publication bias detected.

Conclusions

Care at CACs was associated with improved survival and neurological outcomes for patients with nontraumatic out‐of‐hospital cardiac arrest regardless of varying CAC definitions. Patients with shockable rhythms and those without prehospital return of spontaneous circulation benefited more from CACs. Evidence for bypassing hospitals or interhospital transfer remains inconclusive.

Postresuscitation care and prognostication

PURPOSE OF REVIEW

Most patients who are successfully resuscitated after cardiac arrest are initially comatose and require mechanical ventilation and other organ support in an ICU. Knowledge about the optimal strategy for treating these patients is evolving rapidly. This review will summarize the evidence on key aspects of postarrest care and prognostication, with a focus on actionable parameters that may impact patient survival and neurologic outcomes.

RECENT FINDINGS

Optimal targets for arterial blood oxygen and carbon dioxide in comatose postcardiac arrest patients remain uncertain. Observational data are conflicting and the few randomized controlled trials to date have failed to show that different ranges of blood oxygen and carbon dioxide values impact on biomarkers of neurological injury. The Targeted Temperature Management 2 (TTM-2) trial has documented no difference in 6-month mortality among comatose postcardiac arrest patients managed at 33 oC versus controlled normothermia. An extensive systematic review of the evidence on prognostication of outcome among comatose postcardiac arrest patients underpins new prognostication guidelines.

SUMMARY

Clinical guidelines for postresuscitation care have recently been updated and incorporate all the available science supporting the treatment of postcardiac arrests. At a minimum, fever should be strictly avoided in comatose postcardiac patients. Prognostication must involve multiple modalities and should not be attempted until assessment confounders have been sufficiently excluded.