Out-of-hospital cardiac arrest patients treated with cardiopulmonary resuscitation using extracorporeal membrane oxygenation: focus on survival rate and neurologic outcome

Association between pupillary examinations and prognosis in patients with out-of-hospital cardiac arrest who underwent extracorporeal cardiopulmonary resuscitation: a retrospective multicentre cohort study

BACKGROUND

In some cases of patients with out-of-hospital cardiac arrest (OHCA) who underwent extracorporeal cardiopulmonary resuscitation (ECPR), negative pupillary light reflex (PLR) and mydriasis upon hospital arrival serve as common early indicator of poor prognosis. However, in certain patients with poor prognoses inferred by pupil findings upon hospital arrival, pupillary findings improve before and after the establishment of ECPR. The association between these changes in pupillary findings and prognosis remains unclear. This study aimed to clarify the association of pupillary examinations before and after the establishment of ECPR in patients with OHCA showing poor pupillary findings upon hospital arrival with their outcomes. To this end, we analysed retrospective multicentre registry data involving 36 institutions in Japan, including all adult patients with OHCA who underwent ECPR between January 2013 and December 2018. We selected patients with poor prognosis inferred by pupillary examinations, negative pupillary light reflex (PLR) and pupil mydriasis, upon hospital arrival. The primary outcome was favourable neurological outcome, defined as Cerebral Performance Category 1 or 2 at hospital discharge. Multivariable logistic regression analysis was performed to evaluate the association between favourable neurological outcome and pupillary examination after establishing ECPR.

RESULTS

Out of the 2,157 patients enrolled in the SAVE-J II study, 723 were analysed. Among the patients analysed, 74 (10.2%) demonstrated favourable neurological outcome at hospital discharge. Multivariable analysis revealed that a positive PLR at ICU admission (odds ration [OR] = 11.3, 95% confidence intervals [CI] = 5.17-24.7) was significantly associated with favourable neurological outcome. However, normal pupil diameter at ICU admission (OR = 1.10, 95%CI = 0.52-2.32) was not significantly associated with favourable neurological outcome.

CONCLUSION

Among the patients with OHCA who underwent ECPR and showed poor pupillary examination findings upon hospital arrival, 10.2% had favourable neurological outcome at hospital discharge. A positive PLR after the establishment of ECPR was significantly associated with favourable neurological outcome.

Recovery and Survival of Patients After Out-of-Hospital Cardiac Arrest: A Literature Review Showcasing the Big Picture of Intensive Care Unit-Related Factors

As an important public health issue, out-of-hospital cardiac arrest (OHCA) requires several stages of high quality medical care, both on-field and after hospital admission. Post-cardiac arrest shock can lead to severe neurological injury, resulting in poor recovery outcome and increased risk of death. These characteristics make this condition one of the most important issues to deal with in post-OHCA patients hospitalized in intensive care units (ICUs). Also, the majority of initial post-resuscitation survivors have underlying coronary diseases making revascularization procedure another crucial step in early management of these patients. Besides keeping myocardial blood flow at a satisfactory level, other tissues must not be neglected as well, and maintaining mean arterial pressure within optimal range is also preferable. All these procedures can be simplified to a certain level along with using targeted temperature management methods in order to decrease metabolic demands in ICU-hospitalized post-OHCA patients. Additionally, withdrawal of life-sustaining therapy as a controversial ethical topic is under constant re-evaluation due to its possible influence on overall mortality rates in patients initially surviving OHCA. Focusing on all of these important points in process of managing ICU patients is an imperative towards better survival and complete recovery rates.

Risk factors for bleeding complications in patients undergoing extracorporeal cardiopulmonary resuscitation following out-of-hospital cardiac arrest: a secondary analysis of the SAVE-J II study

BACKGROUND

Bleeding is the most common complication in out-of-hospital cardiac arrest (OHCA) patients receiving extracorporeal cardiopulmonary resuscitation (ECPR). No studies comprehensively described the incidence rate, timing of onset, risk factors, and treatment of bleeding complications in OHCA patients receiving ECPR in a multicenter setting with a large database. This study aimed to analyze the risk factors of bleeding during the first day of admission and to comprehensively describe details of bleeding during hospitalization in patients with OHCA receiving ECPR in the SAVE-J II study database.

METHODS

This study was a secondary analysis of the SAVE-J II study, which is a multicenter retrospective registry study from 36 participating institutions in Japan in 2013-2018. Adult OHCA patients who received ECPR were included. The primary outcome was the risk factor of bleeding complications during the first day of admission. The secondary outcomes were the details of bleeding complications and clinical outcomes.

RESULTS

A total of 1,632 patients were included. Among these, 361 patients (22.1%) had bleeding complications during hospital stay, which most commonly occurred in cannulation sites (14.3%), followed by bleeding in the retroperitoneum (2.8%), gastrointestinal tract (2.2%), upper airway (1.2%), and mediastinum (1.1%). These bleeding complications developed within two days of admission, and 21.9% of patients required interventional radiology (IVR) or/and surgical interventions for hemostasis. The survival rate at discharge of the bleeding group was 27.4%, and the rate of favorable neurological outcome at discharge was 14.1%. Multivariable logistic regression analysis showed that the platelet count (< 10 × 104/μL vs > 10 × 104/μL) was significantly associated with bleeding complications during the first day of admission (adjusted odds ratio [OR]: 1.865 [1.252-2.777], p = 0.002).

CONCLUSIONS

In a large ECPR registry database in Japan, up to 22.1% of patients experienced bleeding complications requiring blood transfusion, IVR, or surgical intervention for hemostasis. The initial platelet count was a significant risk factor of early bleeding complications. It is necessary to lower the occurrence of bleeding complications from ECPR, and this study provided an additional standard value for future studies to improve its safety.

Urine output as one of the most important features in differentiating in-hospital death among patients receiving extracorporeal membrane oxygenation: a random forest approach

BACKGROUND

It is common to support cardiovascular function in critically ill patients with extracorporeal membrane oxygenation (ECMO). The purpose of this study was to identify patients receiving ECMO with a considerable risk of dying in hospital using machine learning algorithms.

METHODS

A total of 1342 adult patients on ECMO support were randomly assigned to the training and test groups. The discriminatory power (DP) for predicting in-hospital mortality was tested using both random forest (RF) and logistic regression (LR) algorithms.

RESULTS

Urine output on the first day of ECMO implantation was found to be one of the most predictive features that were related to in-hospital death in both RF and LR models. For those with oliguria, the hazard ratio for 1 year mortality was 1.445 (p < 0.001, 95% CI 1.265-1.650).

CONCLUSIONS

Oliguria within the first 24 h was deemed especially significant in differentiating in-hospital death and 1 year mortality.

Hypothermia may reduce mortality and improve neurologic outcomes in adult patients treated with VA-ECMO: A systematic review and meta-analysis

BACKGROUND

VA-ECMO can greatly reduce mortality in critically ill patients, and hypothermia attenuates the deleterious effects of ischemia-reperfusion injury. We aimed to study the effects of hypothermia on mortality and neurological outcomes in VA-ECMO patients.

METHODS

A systematic search of the PubMed, Embase, Web of Science, and Cochrane Library databases was performed from the earliest available date to 31 December 2022. The primary outcome was discharge or 28-day mortality and favorable neurological outcomes in VA-ECMO patients, and the secondary outcome was bleeding risk in VA-ECMO patients. The results are presented as odds ratios (ORs) and 95% confidence intervals (CIs). Based on the heterogeneity assessed by the I2 statistic, meta-analyses were performed using random or fixed-effects models. GRADE methodology was used to rate the certainty in the findings.

RESULTS

A total of 27 articles (3782 patients) were included. Hypothermia (33-35 °C) lasting at least 24 h can significantly reduce discharge or 28-day mortality (OR, 0.45; 95% CI, 0.33-0.63; I2 = 41%) and significantly improve favorable neurological outcomes (OR, 2.08; 95% CI, 1.66-2.61; I2 = 3%) in VA-ECMO patients. Additionally, there was no risk associated with bleeding (OR, 1.15; 95% CI, 0.86-1.53; I2 = 12%). In our subgroup analysis according to in-hospital or out-of-hospital cardiac arrest, hypothermia reduced short-term mortality in both VA-ECMO-assisted in-hospital (OR, 0.30; 95% CI, 0.11-0.86; I2 = 0.0%) and out-of-hospital cardiac arrest (OR, 0.41; 95% CI, 0.25-0.69; I2 = 52.3%). Out-of-hospital cardiac arrest patients assisted by VA-ECMO for favorable neurological outcomes were consistent with the conclusions of this paper (OR, 2.10; 95% CI, 1.63-2.72; I2 = 0.5%).

CONCLUSIONS

Our results show that mild hypothermia (33-35 °C) lasting at least 24 h can greatly reduce short-term mortality and significantly improve favorable short-term neurologic outcomes in VA-ECMO-assisted patients without bleeding-related risks. As the grade assessment indicated that the certainty of the evidence was relatively low, hypothermia as a strategy for VA-ECMO-assisted patient care may need to be treated with caution.

Predictors of Mortality in Patients With Refractory Cardiac Arrest Supported With VA-ECMO: A Systematic Review and a Meta-Analysis

Cardiac arrest (CA) is associated with high mortality rate, ranging between 75% and 93%. Given its significance, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been used for end-organs perfusion and to maintain adequate oxygenation as a life-saving option in refractory CA. The predictors for the success of VA-ECMO in this setting have not been established yet. In this meta-analysis, we aim to identify the variables associated with increased mortality in patients with CA supported with VA-ECMO. We conducted a systematic review and meta-analysis to evaluate mortality-predicting factors in patients with CA supported with VA-ECMO that were published between January 2000 and July 2022. To identify relevant articles, the MEDLINE (Pubmed, Ovid) and Cochrane Databases were queried with various combinations of our prespecified keywords, including VA-ECMO, CA, and mortality predictors. We performed a meta-analysis using a random-effects model to calculate the odds ratio (OR). We retrieved a total of 4476 records, out of which we included 10 observational studies in our study. A total of 931 patients were included in our study with the age range of 47-68 years, predominantly males (63.9%). The overall mortality was 69.4%. The predictors for mortality were age >65 (OR 4.61, 95% CI 1.63-13.03, P < 0.01), history of chronic kidney disease (OR 2.42, 95% CI 1.37-4.28, P < 0.01), cardiopulmonary resuscitation duration prior to ECMO > 40 minutes (OR 6.62 [95% CI 1.39, 9.02], P < 0.01), having an initial nonshockable rhythm (OR 2.62 [95% CI 1.85, 3.70], P < 0.01) and sequential organ failure assessment score >14 (OR 12.29, 95% CI 2.71-55.74, P <0.01). Regarding blood work, an increase in lactate by 5 mmol/L increased the odds of mortality by 121% (2 studies; OR 2.21 [95% CI 1.26, 3.86], P < 0.01; I2 = 0%) while the increase in lactate by 1 mmol/L increases odd of mortality by 15% (2 studies, OR 1.15 [95% CI 1.02, 1.31], P = 0.03, I = 0%), and an increase in creatinine by 1 mg/dL increased the odds of mortality by 225% (1 study; OR 3.25 [95% CI 1.22, 8.7], P = 0.02). Albumin was protective as for each 1 g/dL increase, the odds of mortality decreased by 68% (1 study; OR 0.32 [95% CI 0.14, 0.74], P < 0.01). Refractory CA requiring VA-ECMO has a high mortality. Predictors of mortality include age >65, history of chronic kidney disease, cardiopulmonary resuscitation duration prior to ECMO > 40 minutes, initial rhythm being non-shockable and Sequential Organ Failure Assessment score >14.

External validation of the TiPS65 score for predicting good neurological outcomes in patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation

AIM

Estimating prognosis of patients treated with extracorporeal cardiopulmonary resuscitation (ECPR) is essential for selecting candidates. The TiPS65 score can predict neurological outcomes of patients with out-of-hospital cardiac arrest (OHCA) treated with ECPR. We aimed to perform an external validation of this score.

METHODS

Data from the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest registry, a multicentred, nationwide, prospectively registered database, were analysed. All adult patients with OHCA and shockable rhythm and treated with ECPR between January 2018 to December 2019 were included. In the TiPS65 score, age, call-to-hospital arrival time, initial cardiac rhythm at hospital arrival, and initial pH value were used as predictors. The primary outcome was 30-day survival with favourable neurological outcomes (Cerebral Performance Category 1 or 2). Discrimination, using the C-statistic, and predictive performances of each score, such as sensitivity and specificity, were investigated.

RESULTS

Of 590 included patients (517 [81.6%] men; median [interquartile range] age, 60 [50-69] years), 64 (10.8%) reported favourable neurological outcomes. The C-statistic of the TiPS65 score was 0.729 (95% confidence interval (CI): 0.672-0.786). When the cut-off of TiPS65 score was set to >1, the sensitivity and specificity were 0.906 (95%CI: 0.807-0.965) and 0.430 (95%CI: 0.387-0.473), respectively; conversely, when the cut-off was set to >3, they were 0.172 (95%CI: 0.089-0.287) and 0.971 (95%CI: 0.953-0.984), respectively.

CONCLUSIONS

The TiPS65 score shows reasonable discrimination and predictive performances. This score can be supportive in the decision-making process for the selection of eligible patients for ECPR in clinical settings.

Extracorporeal life support in adult patients with out-of-hospital cardiac arrest

The use of extracorporeal life support in cardiopulmonary resuscitation (CPR) of adult patients experiencing out-of-hospital cardiac arrest by the application of veno-arterial extracorporeal membrane oxygenation (ECMO) during cardiac arrest has been increasing over the past decade. This can be attributed to the encouraging results of extracorporeal CPR (ECPR) in multiple observational studies. To date, only one randomised controlled trial has compared ECPR to conventional advanced life support measures. Patient selection is crucial for the success of ECPR programmes. A rapid and organised approach is required for resuscitation, i.e. cannula insertion with ECMO pump initiation in combination with other aspects of post-cardiac arrest care such as targeted temperature management and early coronary reperfusion. The provision of an ECPR service can be costly, resource intensive and technically challenging, as limited studies have reported on its cost-effectiveness.

Enhancing cardiac arrest survival with extracorporeal cardiopulmonary resuscitation: insights into the process of death

Extracorporeal cardiopulmonary resuscitation (ECPR) is an emerging method of cardiopulmonary resuscitation to improve outcomes from cardiac arrest. This approach targets patients with out-of-hospital cardiac arrest previously unresponsive and refractory to standard treatment, combining approximately 1 h of standard CPR followed by venoarterial extracorporeal membrane oxygenation (VA-ECMO) and coronary artery revascularization. Despite its relatively new emergence for the treatment of cardiac arrest, the approach is grounded in a vast body of preclinical and clinical data that demonstrate significantly improved survival and neurological outcomes despite unprecedented, prolonged periods of CPR. In this review, we detail the principles behind VA-ECMO-facilitated resuscitation, contemporary clinical approaches with outcomes, and address the emerging new understanding of the process of death and capability for neurological recovery.

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).

eCPR Combined With Therapeutic Hypothermia Could Improve Survival and Neurologic Outcomes for Patients With Cardiac Arrest: A Meta-Analysis

Background: Extracorporeal membrane oxygenation with CPR (eCPR) or therapeutic hypothermia (TH) seems to be a very effective CPR strategy to save patients with cardiac arrest (CA). Furthermore, the subsequent post-CA neurologic outcomes have become the focus. Therefore, there is an urgent need to find a way to improve survival and neurologic outcomes for CA. Objective: We conducted this meta-analysis to find a more suitable CPR strategy for patients with CA. Method: We searched four online databases (PubMed, Embase, CENTRAL, and Web of Science). From an initial 1,436 articles, 23 studies were eligible into this meta-analysis, including a total of 2,035 patients. Results: eCPR combined with TH significantly improved the short-term (at discharge or 28 days) survival [OR = 2.27, 95% CIs (1.60-3.23), p < 0.00001] and neurologic outcomes [OR = 2.60, 95% CIs (1.92-3.52), p < 0.00001). At 3 months of follow-up, the results of survival [OR = 3.36, 95% CIs (1.65-6.85), p < 0.0008] and favorable neurologic outcomes [OR = 3.02, 95% CIs (1.38-6.63), p < 0.006] were the same as above. Furthermore, there was no difference in any bleeding needed intervention [OR = 1.33, 95% CIs (0.09-1.96), p = 0.16] between two groups. Conclusions: From this meta-analysis, we found that eCPR combined with TH might be a more suitable CPR strategy for patients with CA in improving survival and neurologic outcomes, and eCPR with TH did not increase the risk of bleeding. Furthermore, single-arm meta-analyses showed a plausible way of temperature and occasion of TH.

Overview of Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) Support for the Management of Cardiogenic Shock

Cardiogenic shock accounts for ~100,000 annual hospital admissions in the United States. Despite improvements in medical management strategies, in-hospital mortality remains unacceptably high. Multiple mechanical circulatory support devices have been developed with the aim to provide hemodynamic support and to improve outcomes in this population. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is the most advanced temporary life support system that is unique in that it provides immediate and complete hemodynamic support as well as concomitant gas exchange. In this review, we discuss the fundamental concepts and hemodynamic aspects of VA-ECMO support in patients with cardiogenic shock of various etiologies. In addition, we review the common indications, contraindications and complications associated with VA-ECMO use.

ECPR-extracorporeal cardiopulmonary resuscitation

Extracorporeal cardiopulmonary resuscitation (ECPR) is a salvage procedure in which extracorporeal membrane oxygenation (ECMO) is initiated emergently on patients who have had cardiac arrest (CA) and on whom the conventional cardiopulmonary resuscitation (CCPR) has failed. Awareness and usage of ECPR are increasing all over the world. Significant advancements have taken place in the ECPR initiation techniques, in its device and in its post-procedure care. ECPR is a team work requiring multidisciplinary experts, highly skilled health care workers and adequate infrastructure with appropriate devices. Perfect coordination and communication among team members play a vital role in the outcome of the ECPR patients. Ethical, legal and financial issues need to be considered before initiation of ECPR and while withdrawing the support when the ECPR is futile. Numerous studies about ECPR are being published more frequently in the last few years. Hence, keeping updated about the ECPR is very important for proper selection of cases and its management. This article reviews various aspects of ECPR and relevant literature to date.

Extracorporeal cardiopulmonary resuscitation for adults with shock-refractory cardiac arrest

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation has increasingly emerged as a feasible treatment to mitigate the progressive multiorgan dysfunction that occurs during cardiac arrest, in support of further resuscitation efforts.

OBJECTIVES

Because the recent systematic review commissioned in 2018 by the International Liaison Committee on Resuscitation Advanced Life Support task did not include studies without a control group, our objective was to conduct a review incorporating these studies to increase available evidence supporting the use of extracorporeal cardiopulmonary resuscitation (ECPR) for cardiac arrest patients, while waiting for high-quality evidence from randomized controlled trials (RCTs).

METHODS

MEDLINE, Embase, and Science Citation Index (Web of Science) were searched for eligible studies from database inception to July 20, 2020. The population of interest was adult patients who had suffered cardiac arrest in any setting. We included all cohort studies with 1 exposure/1 group and descriptive studies (ie, case series studies). We excluded RCTs, non-RCTs, and observational analytic studies with a control group. Outcomes included short-term survival and favorable neurological outcome. Short-term outcomes (ie, hospital discharge, 30 days, and 1 month) were combined into a single category.

RESULTS

Our searches of databases and other sources yielded a total of 4302 citations. Sixty-two eligible studies were included (including a combined total of 3638 participants). Six studies were of in-hospital cardiac arrest, 34 studies were of out-of-hospital cardiac arrest, and 22 studies included both in-hospital and out-of-hospital cardiac arrest. Seven hundred and sixty-eight patients of 3352 (23%) had short-term survival; whereas, 602 of 3366 (18%) survived with favorable neurological outcome, defined as a cerebral performance category score of 1 or 2.

CONCLUSIONS

Current clinical evidence is mostly drawn from observational studies, with their potential for confounding selection bias. Although studies without controls cannot supplant case-control or cohort studies, several ECPR studies without a control group show successful resuscitation with impressive results that may provide valuable information to inform a comparison.

Rationale and methods of the Advanced R2Eperfusion STrategies for Refractory Cardiac Arrest (ARREST) trial

BACKGROUND

Venoarterial extracorporeal membrane oxygenation has emerged as a prominent therapy for patients with refractory cardiac arrest. However, the optimal time of initiation remains unknown.

AIM

The aim was to assess the rate of survival to hospital discharge in adult patients with refractory ventricular fibrillation/pulseless ventricular tachycardia out-of-hospital cardiac arrest treated with 1 of 2 local standards of care: (1) early venoarterial extracorporeal membrane oxygenation-facilitated resuscitation for circulatory support and percutaneous coronary intervention, when needed, or (2) standard advanced cardiac life support resuscitation.

DESIGN

Phase II, single-center, partially blinded, prospective, intention-to-treat, safety and efficacy clinical trial.

POPULATION

Adults (aged 18-75), initial out-of-hospital cardiac arrest rhythm of ventricular fibrillation/pulseless ventricular tachycardia, no ROSC following 3 shocks, body morphology to accommodate a Lund University Cardiac Arrest System automated cardiopulmonary resuscitation device, and transfer time of <30 minutes.

SETTING

Hospital-based.

OUTCOMES

Primary: survival to hospital discharge. Secondary: safety, survival, and functional assessment at hospital discharge and 3 and 6 months, and cost.

SAMPLE SIZE

Assuming success rates of 12% versus 37% in the 2 arms and 90% power, a type 1 error rate of .05, and a 15% rate of withdrawal prior to hospital discharge, the required sample size is N = 174 evaluated patients.

CONCLUSIONS

The ARREST trial will generate safety/effectiveness data and comparative costs associated with extracorporeal cardiopulmonary resuscitation, informing broader implementation and a definitive Phase III clinical trial.

Extracorporeal cardiopulmonary resuscitation for in- and out-of-hospital cardiac arrest: systematic review and meta-analysis of propensity score-matched cohort studies

INTRODUCTION

In this systematic review and meta-analysis of propensity score-matched cohort studies, we quantitatively summarize whether venoarterial extracorporeal membrane oxygenation (VA-ECMO) used as extracorporeal cardiopulmonary resuscitation (ECPR), compared with conventional cardiopulmonary resuscitation (CCPR), is associated with improved rates of 30-day and long-term favorable neurological outcomes and survival in patients resuscitated from in- and out-of-hospital cardiac arrest.

METHODS

We searched MEDLINE via PubMed, Embase, Scopus, and Google Scholar for eligible studies on January 14, 2019. All searches were limited to studies published between January 2000 and January 2019. Two investigators independently evaluated the quality (or certainty) of evidence according to GRADE guidelines. Pooled results are presented as relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

Six cohort studies using propensity score-matched analysis were included, totaling 1108 matched patients. Pooled analyses showed that ECPR was likely associated with improved 30-day and long-term favorable neurological outcome in adults compared to CCPR for in- and out-of-hospital cardiac arrest (RR = 2.02, 95% CI = 1.29-3.16; I2 = 20%, P = 0.002; very low-quality evidence) and (RR = 2.86, 95% CI = 1.64-5.01; I2 = 0%, P = 0.0002; moderate-quality evidence), respectively. When we analyzed in- and out-of-hospital cardiac arrest separately, ECPR was likely associated with improved 30-day favorable neurological outcome compared to CCPR for in-hospital cardiac arrest (RR = 2.18, 95% CI = 1.24-3.81; I2 = 9%, P = 0.006; very low-quality evidence), but not for out-of-hospital cardiac arrest (RR = 2.61, 95% CI = 0.56-12.20; I2 = 59%, P = 0.22; very low-quality evidence). ECPR was also likely associated with improved long-term favorable neurological outcome compared to CCPR for in-hospital cardiac arrest (RR = 2.50, 95% CI = 1.33-4.71; I2 = 0%, P = 0.005; moderate-quality evidence) and out-of-hospital cardiac arrest (RR = 4.64, 95% CI = 1.41-15.25; I2 = 0%, P = 0.01; moderate-quality evidence).

CONCLUSIONS

Our analysis suggests that VA-ECMO used as ECPR may improve long-term favorable neurological outcomes and survival when compared to the best standard of care in a selected patient population. Therefore, it is imperative for well-designed randomized clinical trials to obtain a higher level of scientific evidence to ensure optimal outcomes for cardiac arrest patients.

Impact of Transport Time and Cardiac Arrest Centers on the Neurological Outcome After Out-of-Hospital Cardiac Arrest: A Retrospective Cohort Study

Background

Should all out‐of‐hospital cardiac arrest (OHCA) patients be directly transported to cardiac arrest centers (CACs) remains under debate. Our study evaluated the impacts of different transport time and destination hospital on the outcomes of OHCA patients.

Methods and Results

Data were collected from 6655 OHCA patients recorded in the regional prospective OHCA registry database of Taoyuan City, Taiwan, between January 2012 and December 2016. Patients were matched on propensity score, which left 5156 patients, 2578 each in the CAC and non‐CAC groups. Transport time was dichotomized into <8 and ≥8 minutes. The relations between the transport time to CACs and good neurological outcome at discharge and survival to discharge were investigated. Of the 5156 patients, 4215 (81.7%) presented with nonshockable rhythms and 941 (18.3%) presented with shockable rhythms. Regardless of transport time, transportation to a CAC increased the likelihoods of survival to discharge (<8 minutes: adjusted odds ratio [aOR], 1.95; 95% CI, 1.11–3.41; ≥8 minutes: aOR, 1.92; 95% CI, 1.25–2.94) and good neurological outcome at discharge (<8 minutes: aOR, 2.70; 95% CI, 1.40–5.22; ≥8 minutes: aOR, 2.20; 95% CI, 1.29–3.75) in OHCA patients with shockable rhythms but not in patients with nonshockable rhythms.

Conclusions

OHCA patients with shockable rhythms transported to CACs demonstrated higher probabilities of survival to discharge and a good neurological outcome at discharge. Direct ambulance delivery to CACs should thus be considered, particularly when OHCA patients present with shockable rhythms.

[Preclinical management of cardiac arrest-extracorporeal cardiopulmonary resuscitation]

BACKGROUND

The chances of surviving out-of-hospital cardiac arrest (OHCA) are still very low. Despite intensive efforts the outcome has remained relatively poor over many years. In specific situations, new technologies, such as extracorporeal cardiopulmonary resuscitation (eCPR) could significantly improve survival with a good neurological outcome.

OBJECTIVE

Does the immediate restoration of circulation and reoxygenation via eCPR influence the survival rate after OHCA? Is eCPR the new link in the chain of survival?

MATERIAL AND METHODS

Discussion of current study results and guideline recommendations.

RESULTS

The overall survival rates after OHCA have remained at 10-30% over many years. Despite low case numbers more recent retrospective studies showed that an improved outcome can be achieved with eCPR. In selected patient collectives survival with a favorable neurological outcome is possible in 38% of the cases.

CONCLUSION

Survival after cardiac arrest and the subsequent quality of life dependent on many different factors. The time factor, i.e. the avoidance of a no-flow phase and reduction of the low-flow phase is of fundamental importance. The immediate restoration of the circulation and oxygen supply by eCPR can significantly improve survival; however, large randomized, controlled trials are currently not available.

Extracorporeal Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest in Adult Patients

Extracorporeal cardiopulmonary resuscitation (ECPR) followed by targeted temperature management has been demonstrated to significantly improve the outcomes of out-of-hospital cardiac arrest (OHCA) in adult patients. Although recent narrative and systematic reviews on extracorporeal life support in the emergency department are available in the literature, they are focused on the efficacy of ECPR, and no comprehensively summarized review on ECPR for OHCA in adult patients is available. In this review, we aimed to clarify the prevalence, pathophysiology, predictors, management, and details of the complications of ECPR for OHCA, all of which have not been reviewed in previous literature, with the aim of facilitating understanding among acute care physicians. The leading countries in the field of ECPR are those in East Asia followed by those in Europe and the United States. ECPR may reduce the risks of reperfusion injury and deterioration to secondary brain injury. Unlike conventional cardiopulmonary resuscitation, however, no clear prognostic markers have been identified for ECPR for OHCA. Bleeding was identified as the most common complication of ECPR in patients with OHCA. Future studies should combine ECPR with intra-aortic balloon pump, extracorporeal membrane oxygenation flow, target blood pressure, and seizure management in ECPR.

Associations of therapeutic hypothermia with clinical outcomes in patients receiving ECPR after cardiac arrest: systematic review with meta-analysis

BACKGROUND

Therapeutic hypothermia has been recommended for eligible patients after cardiac arrest (CA) in order to improve outcomes. Up to now, several comparative observational studies have evaluated the combined use of extracorporeal cardiopulmonary resuscitation (ECPR) and therapeutic hypothermia in adult patients with CA. However, the effects of therapeutic hypothermia in adult CA patients receiving ECPR are inconsistent.

METHODS

Relevant studies in English databases (PubMed, ISI web of science, OVID, and Embase) were systematically searched up to September 2019. Odds ratios (ORs) from eligible studies were extracted and pooled to summarize the associations of therapeutic hypothermia with favorable neurological outcomes and survival in adult CA patients receiving ECPR.

RESULTS

13 articles were included in the present meta-analysis study. There were nine studies with a total of 806 cases reporting the association of therapeutic hypothermia with neurological outcomes in CA patients receiving ECPR. Pooling analysis suggested that therapeutic hypothermia was significantly associated with favorable neurological outcomes in overall (N = 9, OR = 3.507, 95%CI = 2.194-5.607, P < 0.001, fixed-effects model) and in all subgroups according to control type, regions, sample size, CA location, ORs obtained methods, follow-up period, and modified Newcastle Ottawa Scale (mNOS) scores. There were nine studies with a total of 806 cases assessing the association of therapeutic hypothermia with survival in CA patients receiving ECPR. After pooling the ORs, therapeutic hypothermia was found to be significantly associated with survival in overall (N = 9, OR = 2.540, 95%CI = 1.245-5.180, P = 0.010, random-effects model) and in some subgroups. Publication bias was found when evaluating the association of therapeutic hypothermia with neurological outcomes in CA patients receiving ECPR. Additional trim-and-fill analysis estimated four "missing" studies, which adjusted the effect size to 2.800 (95%CI = 1.842-4.526, P < 0.001, fixed-effects model) for neurological outcomes.

CONCLUSIONS

Therapeutic hypothermia may be associated with favorable neurological outcomes and survival in adult CA patients undergoing ECPR. However, the result should be treated carefully because it is a synthesis of low-level evidence and other limitations exist in present study. It is necessary to perform randomized controlled trials to validate our result before considering the result in clinical practices.

The Influence of Therapeutics on Prognostication After Cardiac Arrest

PURPOSE OF REVIEW

The goal of this review is to highlight the influence of therapeutic maneuvers on neuro-prognostication measures administered to comatose survivors of cardiac arrest. We focus on the effect of sedation regimens in the setting of targeted temperature management (TTM), one of the principle interventions known to improve neurological recovery after cardiac arrest. Further, we discuss the critical need for novel markers, as well as refinement of existing markers, among patients receiving extracorporeal membrane oxygenation (ECMO) in the setting of failed conventional resuscitation, known as extracorporeal cardiopulmonary resuscitation (ECPR).

RECENT FINDINGS

Automated pupillometry may have some advantage over standard pupillary examination for prognostication following TTM, sedation, or the use of ECMO after cardiac arrest. New serum biomarkers such as Neurofilament light chain have shown good predictive abilities and need further validation in these populations. There is a high-level uncertainty in brain death declaration protocols particularly related to apnea testing and appropriate ancillary tests in patients receiving ECMO. Both sedation and TTM alone and in combination have been shown to affect prognostic markers to varying degrees. The optimal approach to analog-sedation is unknown, and requires further study. Moreover, validation of known prognostic markers, as well as brain death declaration processes in patients receiving ECMO is warranted. Data on the effects of TTM, sedation, and ECMO on biomarkers (e.g., neuron-specific enolase) and electrophysiology measures (e.g., somatosensory-evoked potentials) is sparse. The best approach may be one customized to the individual patient, a precision-medicine approach.

The evolving role of novel treatment techniques in the management of patients with refractory VF/pVT out-of-hospital cardiac arrest

STUDY OBJECTIVES

The purpose of this review is to provide a brief overview of new life-saving interventions and novel techniques that have been proposed as viable treatment options for patients presenting with refractory ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT) out-of-hospital cardiac arrest (OHCA).

METHODS

We conducted a comprehensive literature search of PubMed recent, Medline and Embase databases via the Ovid interface and Google Scholar from inception to July 2019. Eligible studies were observational in nature reporting outcomes of extracorporeal membrane oxygenation (ECMO), esmolol, double sequential defibrillation (DSD), and stellate ganglion block (SGB). Two investigators conducted the literature search, study selection, and data extraction. Any disagreements were resolved by consensus.

RESULTS

Our database search identified 5331 records. We included in our review 23 articles that met our inclusion criteria. The selected studies included 16 observational studies on ECMO, 2 observational studies on esmolol, and 5 observational studies on DSD.

CONCLUSION

We would like to suggest that there is not enough evidence in the existing literature to support at large-scale the effects of these techniques in the treatment of refractory VF/pVT OHCA. Randomized studies are warranted to evaluate the significant effects of these approaches against the best current standard of care.

Acute Neurologic Complications During Extracorporeal Membrane Oxygenation: A Systematic Review

OBJECTIVES

We determine the frequency, risk factors, and mortality of neurologic complications in adults on extracorporeal membrane oxygenation and propose an algorithm for preventive strategies.

DATA SOURCES

PubMed, Embase, and Cochrane databases.

STUDY SELECTION

Screening was performed using predefined search terms to identify cohort studies reporting neurologic complications in adults during extracorporeal membrane oxygenation from 1990 to 2017.

DATA EXTRACTION

The final reference list was generated on the basis of relevance to the discussed topics. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation classification of evidence scheme.

DATA SYNTHESIS

In 44 studies, the median frequency of acute neurologic complications is 13% (1-78%; 5% intracranial hemorrhages, 5% ischemic strokes, 2% seizures). Neurologic complications are reported more frequently with venoarterial extracorporeal membrane oxygenation compared with venovenous extracorporeal membrane oxygenation (14 vs eight studies) with a median proportion of complications of 15% (6-33%; 95% CI, 8-19) for venoarterial extracorporeal membrane oxygenation. Median in-hospital mortality is higher with neurologic complications (83%; interquartile range, 54-100% vs 42%; interquartile range, 24-55% without neurologic complications; p < 0.001). Median mortality is 96% for hemorrhages, 84% for ischemic strokes 84%, and 40% for seizures. Risk factors are age, preextracorporeal membrane oxygenation cardiac arrest, hypoglycemia, and administration of inotropes. Hemorrhages are associated with female gender, duration of ventilation and extracorporeal membrane oxygenation, decreased serum fibrinogen, heparin, serum creatinine greater than 2.6 mg/dL, hemodialysis, and thrombocytopenia. Increased odds for ischemic stroke is seen with a preextracorporeal membrane oxygenation serum lactate greater than 10 mmol/L. No studies report daily coagulation monitoring and neurologic assessments, and quality of evidence was low to very low.

CONCLUSIONS

Neurologic complications are reported frequently and with high occurrence rate, especially with venoarterial extracorporeal membrane oxygenation, and associated with high mortality calling for daily weaning from sedation and neuromuscular blockers for neurologic assessment and coagulation monitoring. The low quality of evidence indicates the need for higher quality studies in this context.

The Evolving Role of the Cardiac Catheterization Laboratory in the Management of Patients With Out-of-Hospital Cardiac Arrest: A Scientific Statement From the American Heart Association

Coronary artery disease is prevalent in different causes of out-of-hospital cardiac arrest (OHCA), especially in individuals presenting with shockable rhythms of ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT). The purpose of this report is to review the known prevalence and potential importance of coronary artery disease in patients with OHCA and to describe the emerging paradigm of treatment with advanced perfusion/reperfusion techniques and their potential benefits on the basis of available evidence. Although randomized clinical trials are planned or ongoing, current scientific evidence rests principally on observational case series with their potential confounding selection bias. Among patients resuscitated from VF/pVT OHCA with ST-segment elevation on their postresuscitation ECG, the prevalence of coronary artery disease has been shown to be 70% to 85%. More than 90% of these patients have had successful percutaneous coronary intervention. Conversely, among patients resuscitated from VF/pVT OHCA without ST-segment elevation on their postresuscitation ECG, the prevalence of coronary artery disease has been shown to be 25% to 50%. For these patients, early access to the cardiac catheterization laboratory is associated with a 10% to 15% absolute higher functionally favorable survival rate compared with more conservative approaches of late or no access to the cardiac catheterization laboratory. In patients with VF/pVT OHCA refractory to standard treatment, a new treatment paradigm is also emerging that uses venoarterial extracorporeal membrane oxygenation to facilitate return of normal perfusion and to support further resuscitation efforts, including coronary angiography and percutaneous coronary intervention. The burden of coronary artery disease is high in this patient population, presumably causative in most patients. The strategy of venoarterial extracorporeal membrane oxygenation, coronary angiography, and percutaneous coronary intervention has resulted in functionally favorable survival rates ranging from 9% to 45% in observational studies in this patient population. Patients with VF/pVT should be considered at the highest severity in the continuum of acute coronary syndromes. These patients have a significant burden of coronary artery disease and acute coronary thrombotic events. Evidence from randomized trials will further define optimal clinical practice.

Refractory out-of-hospital cardiac arrest with ongoing cardiopulmonary resuscitation at hospital arrival - survival and neurological outcome without extracorporeal cardiopulmonary resuscitation

Background

The prognosis in refractory out-of-hospital cardiac arrest (OHCA) with ongoing cardiopulmonary resuscitation (CPR) at hospital arrival is often considered dismal. The use of extracorporeal cardiopulmonary resuscitation (eCPR) for perfusion enhancement during resuscitation has shown variable results. We aimed to investigate outcome in refractory OHCA patients managed conservatively without use of eCPR.

Methods

We included consecutive OHCA patients with refractory arrest or prehospital return of spontaneous circulation (ROSC) in the Copenhagen area in 2002–2011.

Results

A total of 3992 OHCA patients with resuscitation attempts were included; in 2599, treatment was terminated prehospital, and 1393 (35%) were brought to the hospital either with ROSC (n = 1285, 92%) or with refractory OHCA (n = 108, 8%). Of patients brought in with refractory OHCA, 56 (52%) achieved ROSC in the emergency department. There were no differences between patients with refractory OHCA or prehospital ROSC with regard to age, sex, comorbidities, or etiology of OHCA. Time to emergency medical services (EMS) arrival was similar, whereas time to ROSC (when ROSC was achieved) was longer in refractory OHCA patients (EMS, 6 (5–9] vs. 7 [5–10] min, p = 0.8; ROSC, 15 [9–22] vs. 27 [20–41] min, p < 0.001). Independent factors associated with transport with refractory OHCA instead of prehospital termination of therapy were OHCA in public (OR, 3.6 [95% CI, 2.2–5.8]; p < 0.001), witnessed OHCA (OR, 3.7 [2.0–7.1]; p < 0.001), shockable rhythm (OR, 3.0 [1.9–4.7]; p < 0.001), younger age (OR, 1.2 [1.1–1.2]; p < 0.001), and later calendar year (OR, 1.4 [1.2–1.6]; p < 0.001). Thirty-day survival was 20% in patients with refractory OHCA compared with 42% in patients with prehospital ROSC (p < 0.001). Four of 28 refractory OHCA patients with duration of resuscitation > 60 min achieved ROSC. No difference in favorable neurological outcome in patients surviving to discharge was found (prehospital ROSC 84% vs. refractory OHCA 86%; p = 0.7).

Conclusions

Survival after refractory OHCA with ongoing CPR at hospital arrival was significantly lower than among patients with prehospital ROSC. Despite a lower survival, the majority of survivors with both refractory OHCA and prehospital ROSC were discharged with a similar degree of favorable neurological outcome, indicating that continued efforts in spite of refractory OHCA are not in vain and may still lead to favorable outcome even without eCPR.

Neurologic outcomes after extracorporeal membrane oxygenation assisted CPR for resuscitation of out-of-hospital cardiac arrest patients: A systematic review

INTRODUCTION

Extracorporeal membrane oxygenation-assisted CPR (ECPR) is an evolving adjunct for resuscitation of OHCA patients. The primary objective of this systematic review was to assess survival-to-hospital discharge with good neurologic recovery after OHCA among patients treated with ECPR compared to conventional CPR (CCPR).

METHODS

A systematic search of MEDLINE® and EMBASE® electronic databases was performed from inception until July 2016 to identify studies reporting ECPR use in adults with OHCA and survival outcomes.

RESULTS

Of the 1512 citations identified, 75 studies met our inclusion criteria (63 case series and 12 cohort studies). Among case series, 0 to 71.4% of patients treated with ECPR survived to discharge with a good neurologic outcome. Subgroup analysis of the cohort studies demonstrated survival-to-hospital discharge with good neurologic recovery in the ECPR group ranging from 8.3 to 41.6% compared to 1.5 to 9.1% in the CCPR group. Five cohort studies adjusted for confounders, 3 of which demonstrated significantly increased adjusted odds ratios of survival among the ECPR-treated patients. Due to significant heterogeneity (I2 = 63%, p = 0.03), pooling of outcomes and a meta-analysis were not conducted.

CONCLUSION

Although a trend towards improved survival with good neurologic outcome was reported in controlled, low-risk of bias cohort studies, a preponderance of low quality evidence may ascribe an optimistic effect size of ECPR on survival among OHCA patients. Our confidence in a clinically relevant difference in outcomes compared to current standards of care for OHCA remains weak. In this state of equipoise, high quality RCT data is urgently needed.

Severe ischaemic cardiogenic shock with cardiac arrest and prolonged asystole: a case report

Background

Extracorporeal life support (ECLS) by veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a valuable treatment option during severe cardiogenic shock and during cardiac arrest unresponsive to conventional management. It is applied to bridge the first critical days until the patient recovers or a destination therapy is established.¹ Prolonged episodes without cardiac electrical activity during VA-ECMO are a major problem, as they may cause pulmonary oedema and severe left ventricular (LV) thrombosis.² Here, we report a case of a 50-year-old man who presented with a 30-h episode of complete absence of electromechanical activity during ECLS and finally recovered with favourable neurological outcome.

Case summary

A 50-year-old man with out-of-hospital cardiac arrest was transferred to a peripheral hospital after initial successful cardiopulmonary resuscitation (CPR). In the emergency room, he presented with ST-segment elevation myocardial infarction and cardiogenic shock with third-degree atrioventricular block. After immediate insertion of a temporary pacemaker, he received percutaneous coronary intervention of the left anterior descending artery and the circumflex artery. Due to worsening cardiogenic shock, ECLS with VA-ECMO and an Impella^® pump was established. Cumulative time of CPR (out of hospital and in hospital) was 41 min. After transfer to our institution’s intensive care unit, both the heart’s mechanical and electrical activity ceased for more than 24 h and recovered slowly thereafter. After showing promising neurological outcome, epicardial pacemaker leads, an implantable cardioverter-defibrillator, and finally, a LV assist device were implanted. He was dismissed into rehabilitation with only minor neurological residua 6 weeks later.

Discussion

Impella^® implantation on top of VA-ECMO may be considered beneficial in the therapy of prolonged cardiac arrest.³ While VA-ECMO ensures oxygenation and organ perfusion, Impella^® vents the left ventricle and enhances coronary perfusion. In the presented case, a favourable outcome was reached despite an ‘untreated’ prolonged absence of cardiac electromechanical activity. Under specific circumstances during ECLS with extracorporeal membrane oxygenation and Impella^®, waiving of temporary pacing may be considered in absent cardiac electromechanical activity to avoid further complications.

Five-year Experience of Extracorporeal Life Support in Emergency Physicians

Background

This study aimed to present our 5-year experience of extracorporeal cardiopulmonary resuscitation (ECPR) performed by emergency physicians.

Methods

We retrospectively analyzed 58 patients who underwent ECPR between January 2010 and December 2014. The primary parameter analyzed was survival to hospital discharge. The secondary parameters analyzed were neurologic outcome at hospital discharge, cannulation time, and ECPR-related complications.

Results

Thirty-one patients (53.4%) were successfully weaned from extracorporeal membrane oxygenation, and 18 (31.0%) survived to hospital discharge. Twelve patients (20.7%) were discharged with good neurologic outcomes. The median cannulation time was 25.0 min (interquartile range 20.0-31.0 min). Nineteen patients (32.8%) had ECPR-related complications, the most frequent being distal limb ischemia. Regarding the initial presentation, 52 patients (83.9%) collapsed due to a cardiac etiology, and acute myocardial infarction (33/62, 53.2%) was the most common cause of cardiac arrest.

Conclusions

The survival to hospital discharge rate for cardiac arrest patients who underwent ECPR conducted by an emergency physician was within the acceptable limits. The cannulation time and complications following ECPR were comparable to those found in previous studies.

Extracorporeal Life Support and New Therapeutic Strategies for Cardiac Arrest Caused by Acute Myocardial Infarction - a Critical Approach for a Critical Condition

This review summarizes the most recent developments in providing advanced supportive measures for cardiopulmonary resuscitation, and the results obtained using these new therapies in patients with cardiac arrest caused by acute myocardial infarction (AMI). Also detailed are new approaches such as extracorporeal cardiopulmonary resuscitation (ECPR), intra-arrest percutaneous coronary intervention, or the regional models for systems of care aiming to reduce the critical times from cardiac arrest to initiation of ECPR and coronary revascularization.