Exploratory Observational Study of Extracorporeal Cardiopulmonary Resuscitation for Nonshockable Out-Of-Hospital Cardiac Arrest Occurring After an Emergency Medical Services Arrival: SOS-KANTO 2012 Study Report

Does extracorporeal cardiopulmonary resuscitation improve survival with favorable neurological outcome in out-of-hospital cardiac arrest? A systematic review and meta-analysis

PURPOSE

Extracorporeal cardiopulmonary resuscitation (E-CPR) may improve survival with favorable neurological outcome in patients with refractory out-of-hospital cardiac arrest (OHCA). Unfortunately, recent results from randomized controlled trials were inconclusive. We performed a meta-analysis to investigate the impact of E-CPR on neurological outcome compared to conventional cardiopulmonary resuscitation (C-CPR).

METHODS

A systematic research for articles assessing outcomes of adult patients with OHCA either treated with E-CPR or C-CPR up to April 27, 2023 was performed. Primary outcome was survival with favorable neurological outcome at discharge or 30 days. Overall survival was also assessed.

RESULTS

Eighteen studies were included. E-CPR was associated with better survival with favorable neurological status at discharge or 30 days (14% vs 7%, OR 2.35, 95% CI 1.61-3.43, I2 = 80%, p < 0.001, NNT = 17) than C-CPR. Results were consistent if the analysis was restricted to RCTs. Overall survival to discharge or 30 days was also positively affected by treatment with E-CPR (OR = 1.71, 95% CI = 1.18-2.46, I2 = 81%, p = 0.004, NNT = 11).

CONCLUSIONS

In this meta-analysis, E-CPR had a positive effect on survival with favorable neurological outcome and, to a smaller extent, on overall mortality in patients with refractory OHCA.

Extracorporeal vs. conventional CPR for out-of-hospital cardiac arrest: A systematic review and meta-analysis

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) remains a significant cause of mortality and morbidity worldwide. Extracorporeal cardiopulmonary resuscitation (ECPR) is a potential intervention for OHCA, but its effectiveness compared to conventional cardiopulmonary resuscitation (CCPR) needs further evaluation.

METHOD

We systematically searched PubMed, Embase, the Cochrane Library, Web of Science, and ClinicalTrials.gov for relevant studies from January 2010 to March 2023. Pooled meta-analysis was performed to investigate any potential association between ECPR and improved survival and neurological outcomes.

RESULTS

This systematic review and meta-analysis included two randomized controlled trials enrolling 162 participants and 10 observational cohort studies enrolling 4507 participants. The pooled meta-analysis demonstrated that compared to CCRP, ECPR did not improve survival and neurological outcomes at 180 days following OHCA (RR: 3.39, 95% CI: 0.79 to 14.64; RR: 2.35, 95% CI: 0.97 to 5.67). While a beneficial effect of ECPR was obtained regarding 30-day survival and neurological outcomes. Furthermore, ECPR was associated with a higher risk of bleeding complications. Subgroup analysis showed that ECPR was prominently beneficial when exclusively initiated in the emergency department. Additional post-resuscitation treatments did not significantly impact the efficacy of ECPR on 180-day survival with favorable neurological outcomes.

CONCLUSIONS

There is no high-quality evidence supporting the superiority of ECPR over CCPR in terms of survival and neurological outcomes in OHCA patients. However, due to the potential for bias, heterogeneity among studies, and inconsistency in practice, the non-significant results do not preclude the potential benefits of ECPR. Further high-quality research is warranted to optimize ECPR practice and provide more generalizable evidence. Clinical trial registration PROSPERO, https://www.crd.york.ac.uk/prospero/, registry number: CRD42023402211.

Impact of clinical variables on outcomes in refractory cardiac arrest patients undergoing extracorporeal cardiopulmonary resuscitation

Background

In the past two decades, extracorporeal resuscitation (ECPR) has been increasingly used in the management of refractory cardiac arrest (CA) patients. Decision algorithms have been used to guide the care such patients, but the effectiveness of such decision-making tools is not well described. The aim of this study was to compare the rate of survival with a good neurologic outcome of patients treated with ECPR meeting all criteria of a clinical decision-making tool for the initiation of ECPR to those for whom ECPR was implemented outside of the algorithm.

Methods

All patients who underwent E-CPR between January 2014 and December 2021 at the Montreal Heart Institute were included in this retrospective analysis. We dichotomized the cohort according to adherence or non-adherence with the ECPR decision-making tool, which included the following criteria: age ≤65 years, initial shockable rhythm, no-flow time <5 min, serum lactate <13 mmol/L. Patients were included in the "IN" group when they met all criteria of the decision-making tool and in the "OUT" group when at least one criterion was not met.

Main outcomes and measures

The primary outcome was survival with intact neurological status at 30 days, defined by a Cerebral Performance Category (CPC) Scale 1 and 2.

Results

A total of 41 patients (IN group, n = 11; OUT group, n = 30) were included. A total of 4 (36%) patients met the primary outcome in the IN group and 7 (23%) in the OUT group [odds ratio (OR): 1.88 (95% CI, 0.42-8.34); P = 0.45]. However, survival with a favorable outcome decreased steadily with 2 or more deviations from the decision-making tool [2 deviations: 1 (11%); 3 deviations: 0 (0%)].

Conclusion and relevance

Most patients supported with ECPR fell outside of the criteria encompassed in a clinical decision-making tool, which highlights the challenge of optimal selection of ECPR candidates. Survival rate with a good neurologic outcome did not differ between the IN and OUT groups. However, survival with favorable outcome decreased steadily after one deviation from the decision-making tool. More studies are needed to help select proper candidates with refractory CA patients for ECPR.

Association between Conversion to Shockable Rhythms and Survival with Favorable Neurological Outcomes for Out-of-Hospital Cardiac Arrests

BACKGROUND

The initial cardiac rhythm in out-of-hospital cardiac arrest (OHCA) portends different prognoses and affects treatment decisions. Initial shockable rhythms are associated with good survival and neurological outcomes but there is conflicting evidence for those who initially present with non-shockable rhythms. The aim of this study is to evaluate if OHCA with conversion from non-shockable (i.e., asystole and pulseless electrical activity) rhythms to shockable rhythms compared to OHCA remaining in non-shockable rhythms is associated with better survival and neurological outcomes.

METHOD

OHCA cases from the Pan-Asian Resuscitation Outcomes Study registry in 13 countries between January 2009 and February 2018 were retrospectively analyzed. Cases with missing initial rhythms, age <18 years, presumed non-medical cause of arrest, and not conveyed by emergency medical services were excluded. Multivariable logistic regression analysis was performed to evaluate the relationship between initial and subsequent shockable rhythm, survival to discharge, and survival with favorable neurological outcomes (cerebral performance category 1 or 2).

RESULTS

Of the 116,387 cases included. 11,153 (9.6%) had initial shockable rhythms and 9,765 (8.4%) subsequently converted to shockable rhythms. Japan had the lowest proportion of OHCA patients with initial shockable rhythms (7.3%). For OHCA with initial shockable rhythm, the adjusted odds ratios (aOR) for survival and good neurological outcomes were 8.11 (95% confidence interval [CI] 7.62-8.63) and 15.4 (95%CI 14.1-16.8) respectively. For OHCA that converted from initial non-shockable to shockable rhythms, the aORs for survival and good neurological outcomes were 1.23 (95%CI 1.10-1.37) and 1.61 (95%CI 1.35-1.91) respectively. The aORs for survival and good neurological outcomes were 1.48 (95%CI 1.22-1.79) and 1.92 (95%CI 1.3 - 2.84) respectively for initial asystole, while the aOR for survival in initial pulseless electrical activity patients was 0.83 (95%CI 0.71-0.98). Prehospital adrenaline administration had the highest aOR (2.05, 95%CI 1.93-2.18) for conversion to shockable rhythm.

CONCLUSION

In this ambidirectional cohort study, conversion from non-shockable to shockable rhythm was associated with improved survival and neurologic outcomes compared to rhythms that continued to be non-shockable. Continued advanced resuscitation may be beneficial for OHCA with subsequent conversion to shockable rhythms.

Clinical characteristics and outcomes after extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients with an initial asystole rhythm

AIM

This study aimed to describe the characteristics of cases of out-of-hospital cardiac arrest (OHCA) with an initial asystole rhythm in which extracorporeal cardiopulmonary resuscitation (ECPR) was introduced and discuss the clinical indications for ECPR in such patients.

METHODS

This was a secondary analysis of the SAVE-J II study, a retrospective, multicentre, registry study involving 36 participating institutions in Japan. Patients with an initial asystole rhythm were selected. Favourable neurological outcomes (cerebral performance categories 1-2) constituted the primary outcome.

RESULTS

In total, 202 patients met the inclusion criteria, with favourable neurological outcomes at hospital discharge in 12 patients (5.9%). Causes of cardiac arrest with favourable neurological outcomes were hypothermia (7 cases), acute coronary syndrome (2 cases), arrhythmia (2 cases), and pulmonary embolism (1 case). Among patients with non-hypothermia (temperature ≥32 °C) on hospital arrival with the cardiac rhythm of asystole or pulseless electrical activity (PEA) on arrival, all 107 patients (66 asystole, 41 PEA) who lacked one or more of the requirements (witness; bystander CPR; signs of life or pupil < 5 mm) had unfavourable neurological outcomes. All 5 cases with favourable neurological outcomes, except for 1 case with a short duration of no-flow time that was highly suspected based on the patient's history, met all the requirements on hospital arrival.

CONCLUSIONS

A total of 202 ECPR cases with an initial asystole rhythm, including 12 patients with favourable neurological outcomes, were described. Even if the initial cardiac rhythm is asystole, ECPR could be considered if certain conditions are met.

Extracorporeal cardiopulmonary resuscitation for cardiac arrest: An updated systematic review

OBJECTIVES

To provide an updated systematic review on the use of extracorporeal cardiopulmonary resuscitation (ECPR) compared with manual or mechanical cardiopulmonary resuscitation during cardiac arrest.

METHODS

This was an update of a systematic review published in 2018. OVID Medline, Embase, and the Cochrane Central Register of Controlled Trials were searched for randomized trials and observational studies between January 1, 2018, and June 21, 2022. The population included adults and children with out-of-hospital or in-hospital cardiac arrest. Two investigators reviewed studies for relevance, extracted data, and assessed bias. The certainty of evidence was evaluated using GRADE.

RESULTS

The search identified 3 trials, 27 observational studies, and 6 cost-effectiveness studies. All trials included adults with out-of-hospital cardiac arrest and were terminated before enrolling the intended number of subjects. One trial found a benefit of ECPR in survival and favorable neurological status, whereas two trials found no statistically significant differences in outcomes. There were 23 observational studies in adults with out-of-hospital cardiac arrest or in combination with in-hospital cardiac arrest, and 4 observational studies in children with in-hospital cardiac arrest. Results of individual studies were inconsistent, although many studies favored ECPR. The risk of bias was intermediate for trials and critical for observational studies. The certainty of evidence was very low to low. Study heterogeneity precluded meta-analyses. The cost-effectiveness varied depending on the setting and the analysis assumptions.

CONCLUSIONS

Recent randomized trials suggest potential benefit of ECPR, but the certainty of evidence remains low. It is unclear which patients might benefit from ECPR.

A Comparison between Conventional and Extracorporeal Cardiopulmonary Resuscitation in Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

There is limited evidence comparing the use of extracorporeal cardiopulmonary resuscitation (ECPR) to CPR in the management of refractory out-of-hospital cardiac arrest (OHCA). We conducted a systematic review and meta-analysis to compare survival and neurologic outcomes associated with ECPR versus CPR in the management of OHCA. We searched PubMed, EMBASE, and Scopus to identify observational studies and randomized controlled trials comparing ECPR and CPR. We used the Newcastle−Ottawa Scale and Cochrane’s risk-of-bias tool to assess studies’ quality. We used random-effects models to compare outcomes between the pooled populations and moderator analysis to identify sources of heterogeneity and perform subgroup analysis. We identified 2088 articles and included 13, with 18,620 patients with OHCA. A total of 16,701 received CPR and 1919 received ECPR. Compared with CPR, ECPR was associated with higher odds of achieving favorable neurologic outcomes at 3 (OR 5, 95% CI 1.90−13.1, p < 0.01) and 6 months (OR 4.44, 95% CI 2.3−8.5, p < 0.01). We did not find a significant survival benefit or impact on neurologic outcomes at hospital discharge or 1 month following arrest. ECPR is a promising but resource-intensive intervention with the potential to improve long-term outcomes among patients with OHCA.

Survival and Factors Associated with Survival with Extracorporeal Life Support During Cardiac Arrest: A Systematic Review and Meta-Analysis

The survival rate after cardiac arrest (CA) remains low. The utilization of extracorporeal life support is proposed to improve management. However, this resource-intensive tool is associated with complications and must be used in selected patients. We performed a meta-analysis to determine predictive factors of survival. Among the 81 studies included, involving 9256 patients, survival was 26.2% at discharge and 20.4% with a good neurologic outcome. Meta-regressions identified an association between survival at discharge and lower lactate values, intrahospital CA, and lower cardio pulmonary resuscitation (CPR) duration. After adjustment for age, intrahospital CA, and mean CPR duration, an initial shockable rhythm was the only remaining factor associated with survival to discharge (β = 0.02, 95% CI: 0.007-0.02; p = 0.0004).

[Ethics of resuscitation and end of life decisions]

These European Resuscitation Council Ethics guidelines provide evidence-based recommendations for the ethical, routine practice of resuscitation and end-of-life care of adults and children. The guideline primarily focus on major ethical practice interventions (i.e. advance directives, advance care planning, and shared decision making), decision making regarding resuscitation, education, and research. These areas are tightly related to the application of the principles of bioethics in the practice of resuscitation and end-of-life care.

Impact of a Modified Institutional Protocol on Outcomes After Extracorporeal Cardiopulmonary Resuscitation for Refractory Out-Of-Hospital Cardiac Arrest

OBJECTIVE

To analyze the impact of the modification of the authors' institutional protocol on outcomes after extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA).

DESIGN

An observational analysis. The protocol complied with national recommendations. A further eligibility criterion was added since January 2015: the presence of sustained shockable rhythm at extracorporeal life support (ECLS) implantation. To assess the impact of this change, patients were divided into two groups: (1) from January 2010 to December 2014 (group A) and (2) from January 2015 to December 2019 (group B). The primary endpoint was survival to hospital discharge with good neurologic outcome. Predictors of survival were searched with multivariate analyses.

SETTING

University hospital.

PARTICIPANTS

Adult patients supported with ECPR for refractory OHCA.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

From January 2010 to December 2019, 85 patients had ECLS for OHCA (group A, n = 68, 80%; group B, n = 17, 20%). The mean age was 42.4 years, 78.8% were male. The rate of implantation of ECLS was significantly lower in group B (p = 0.01). Mortality during ECLS support was significantly lower (58.8 v 86.8%; p = 0.008), and the weaning rate was significantly higher (41.2 v 13.2%; p = 0.008) in group B. Survival to discharge with good neurologic outcome was significantly improved (23.5 v 4.4%; p = 0.027) in group B. A sustained shockable rhythm was the only independent predictor of survival to hospital discharge with good neurologic outcome.

CONCLUSIONS

The modification of the authors' institutional protocol throughout the further criterion of sustained shockable rhythm yielded a favorable impact on outcomes after ECPR for OHCA.

European Resuscitation Council Guidelines 2021: Ethics of resuscitation and end of life decisions

These European Resuscitation Council Ethics guidelines provide evidence-based recommendations for the ethical, routine practice of resuscitation and end-of-life care of adults and children. The guideline primarily focus on major ethical practice interventions (i.e. advance directives, advance care planning, and shared decision making), decision making regarding resuscitation, education, and research. These areas are tightly related to the application of the principles of bioethics in the practice of resuscitation and end-of-life care.

CPR and ECMO: The Next Frontier

Cardiopulmonary resuscitation (CPR) is a first-line therapy for sudden cardiac arrest, while extracorporeal membrane oxygenation (ECMO) has traditionally been used as a means of countering circulatory failure. However, new advances dictate that CPR and ECMO could be complementary for support after cardiac arrest. This review details the emerging science, technology, and clinical application that are enabling the new paradigm of these iconic circulatory support modalities in the setting of cardiac arrest.