Extracorporeal Cardiopulmonary Resuscitation for Refractory Out-of-Hospital Cardiac Arrest: The State of the Evidence and Framework for Application

Extracorporeal cardiopulmonary resuscitation-based approach to refractory out-of-hospital cardiac arrest: A focus on organ donation, a secondary analysis of a Prague OHCA randomized study

BACKGROUND

Refractory out-of-hospital cardiac arrest (OHCA) has a poor outcome. In patients, who cannot be rescued despite using advanced techniques like extracorporeal cardiopulmonary resuscitation (ECPR), organ donation may be considered. This study aims to evaluate, in refractory OHCA, how ECPR versus a standard-based approach allows organ donorship.

METHODS

The Prague OHCA trial randomized adults with a witnessed refractory OHCA of presumed cardiac origin to either an ECPR-based or standard approach. Patients who died of brain death or those who died of primary circulatory reasons and were not candidates for cardiac transplantation or durable ventricle assist device were evaluated as potential organ donors by a transplant center. In this post-hoc analysis, the effect on organ donation rates and one-year organ survival in recipients was examined.

RESULTS

Out of 256 enrolled patients, 75 (29%) died prehospitally or within 1 hour after admission and 107 (42%) during the hospital stay. From a total of 24 considered donors, 21 and 3 (p = 0.01) were recruited from the ECPR vs standard approach arm, respectively. Fifteen brain-dead and none cardiac-dead subjects were ultimately accepted, 13 from the ECPR and two from the standard strategy group. A total of 36 organs were harvested. The organs were successfully transplanted into 34 recipients. All transplanted organs were fully functional, and none of the recipients died due to graft failure within the one-year period post-transplant.

CONCLUSION

The ECPR-based approach in the refractory OHCA trial is associated with increased organ donorship and an excellent outcome of transplanted organs.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01511666. Registered January 19, 2012.

The Effects of Extracorporeal Cardiopulmonary Resuscitation According to Covariate Adjustment

This study compared the effects of extracorporeal cardiopulmonary resuscitation (ECPR) using propensity-score matching (PSM) analyses. A nationwide registry of out-of-hospital cardiac arrest (OHCA) patients in Korea between 2013 and 2016 was used. Patients with OHCA aged ≥15 years with cardiac etiology and resuscitation time >30 minutes were enrolled. Resuscitation-related variables before the initiation of ECPR were included. Two PSM analyses were performed separately, with and without post-ECPR variables. The primary outcome (PO) was a favorable neurologic outcome at hospital discharge. The rate of PO was 8.1% (13/161) in the ECPR group and 1.5% (247/16,489) in the conventional CPR (CCPR) group. In the matched cohort with post-ECPR variables, there was no significant difference in the rate of PO between the ECPR and CCPR groups (7.9% vs. 7.9%; p = 0.982). In the matched cohort without post-ECPR variables, the rate of PO was higher in the ECPR group than that in the CCPR group (8.3% vs. 3.6%; p = 0.012). PSM analysis without post-ECPR variables compared outcomes of all patients experiencing OHCA and treated with ECPR versus CCPR, which showed better neurologic outcomes for ECPR. PSM analysis with post-ECPR variables compared outcomes between ECPR survivors and CCPR survivors, which exhibited similar neurologic outcomes.

Potential Candidates for Emergency Department Initiated Extracorporeal Cardiopulmonary Resuscitation (ECPR) in a Canadian Institution

Introduction

Out-of-hospital cardiac arrest (OHCA) patients experience poor survival. The use of extracorporeal membrane oxygenation (ECMO), a form of heart-lung bypass, in the setting of cardiac arrest, termed extracorporeal cardiopulmonary resuscitation (ECPR), has promise in improving survival with good neurologic outcomes. The study objective was to determine the number of potential annual ECPR candidates among the OHCA population in a health region within the Atlantic Canadian province of Nova Scotia.

Methods

A retrospective chart review was conducted over a five-year period: January 1st, 2012 to December 31st, 2016. Consecutive non-traumatic OHCA and emergency department (ED) cardiac arrests occurring in a pre-determined catchment area (20-minute transport to ECMO center) defined by a geographic bounding box were identified. Criteria for ECPR were developed to identify candidates for activation of a “Code ECPR”: (1) age 16-70, (2) witnessed arrest, (3) no flow duration (time to CPR, including bystander) <10 minutes, (4) resuscitation >10 minutes without return of spontaneous circulation (ROSC), (5) emergency medical service (EMS) transport to hospital <20 minutes, (6) no patient factors precluding ongoing resuscitation (do not resuscitate status (DNR), palliative care involvement, or metastatic cancer), and (7) initial rhythm not asystole. Candidates were stratified by initial rhythm. Candidates were considered ultimately ED ECPR eligible if they failed conventional treatment, defined by death or resuscitation >30 minutes. Clinical data related to candidacy was extracted by an electronic query from prehospital and ED electronic records and manual chart review by three researchers.

Results

Our search yielded 561 cases of EMS-treated OHCA or in-ED arrests. Of those 204/561 (36%; 95% CI 33-40%) met the criteria for activation of a “Code ECPR”. Ultimately 79/204 (34%; 95% CI 28-41%) of those who met activation criteria were considered ED ECPR eligible; which is 14% (95% CI 11-17%) of the total number of arrests-of the total number of arrests, the initial rhythms were pulseless electrical activity (PEA) 33/79 (42%; 95% CI 32-53%) and shockable 46/79 (58%; 95% CI 47-69%).

Conclusion

Of all cardiac arrests in the area surrounding our ECMO center, approximately 41 per year met the criteria for a Code ECPR activation, with 16 per year ultimately being eligible for ED ECPR. This annual estimate varies based on the inclusion of initial rhythm. This provides insight into both prehospital and hospital implications of an ED ECPR program and will help guide the establishment of a program within our Nova Scotian health region. This study also provides a framework for similar investigation at other institutions contemplating ED ECPR program implementation.

Program of Uncontrolled Donation After Circulatory Death as Potential Solution to the Shortage of Organs: A Canadian Single-Center Retrospective Cohort Study

Purpose

Worldwide, the number of patients waiting for organ transplantation exceeds the number of organs available. Program for uncontrolled donation after circulatory death (uDCD) implemented in Europe has resulted in a 10–15% expansion of the donor pool. We aimed to describe the number of patients eligible for an uDCD program in a regional tertiary care center.

Methods

We conducted a retrospective cohort study in a Canadian tertiary academic center located in a rural area including all adults who received cardiopulmonary resuscitation in 2016 and died in the emergency department (ED) or during their hospitalization. The primary outcome was the number of patients eligible for uDCD defined as aged between 18 and 60 years old whose collapse was witnessed and where the time between cardiac arrest to cardiopulmonary resuscitation and ED arrival was, respectively, less than 30 and 120 minutes. As a secondary outcome, we determined the number of patients eligible for controlled donation after circulatory death.

Results

Of the 130 patients included, 84 did not return to spontaneous circulation. We identified 15 potential uDCD candidates, with a mean age of 46.6 (95% Confidence Interval [CI] 41.3 to 52) years. Twelve had an out-of-hospital cardiac arrest with a mean time between collapse and arrival to the ED of 43.2 (29.8 to 56.6) minutes. Among the 46 patients who died after a return of spontaneous circulation, 10 (21.7%) were eligible for organ donation after circulatory death.

Conclusion

Implementing an uDCD program in a tertiary hospital covering a rural area could increase the number of donors.

The impact of selection criteria and study design on reported survival outcomes in extracorporeal oxygenation cardiopulmonary resuscitation (ECPR): a systematic review and meta-analysis

Background

The use of extracorporeal membrane oxygenation (ECMO) during cardiac arrest (ECPR) has increased exponentially. However, reported outcomes vary considerably due to differing study designs and selection criteria. This review assessed the impact of pre-defined selection criteria on ECPR survival.

Methods

Systematic review applying PRISMA guidelines. We searched Medline, Embase, and Evidence-Based Medicine Reviews for RCTs and observational studies published from January 2000 to June 2021. Adult patients (> 12 years) receiving ECPR were included. Two investigators reviewed and extracted data on study design, number and type of inclusion criteria. Study quality was assessed using the Newcastle–Ottawa Scale (NOS). Outcomes included overall and neurologically favourable survival. Meta-analysis and meta-regression were performed.

Results

67 studies were included: 14 prospective and 53 retrospective. No RCTs were identified at time of search. The number of inclusion criteria to select ECPR patients (p = 0.292) and study design (p = 0.962) was not associated with higher favourable neurological survival. However, amongst prospective studies, increased number of inclusion criteria was associated with improved outcomes in both OHCA and IHCA cohorts. (β = 0.12, p = 0.026) and arrest to ECMO flow time was predictive of survival. (β = -0.023, p < 0.001).

Conclusions

Prospective studies showed number of selection criteria and, in particular, arrest to ECMO time were associated with significant improved survival. Well-designed prospective studies assessing the relative importance of criteria as well as larger efficacy studies are required to ensure appropriate application of what is a costly intervention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-021-00956-5.

Just the Facts: Extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest

A 58-year-old man is brought by the ambulance to the emergency department (ED) of a tertiary care centre following an out-of-hospital cardiac arrest. Paramedics were called by the patient's wife after he had collapsed. She immediately initiated cardiopulmonary resuscitation (CPR). Prior to his collapse, he had been complaining of chest pain. His initial rhythm in the field was ventricular fibrillation, and he received defibrillation. An automated CPR device was applied prior to transport. En route, return of spontaneous circulation is achieved. An electrocardiogram shows ST-segment elevation in the anterior leads. Just prior to arrival, the patient suffers recurrent cardiac arrest with two further rounds of unsuccessful defibrillation in the ED. At this point, a decision is made to proceed with extracorporeal cardiopulmonary resuscitation (ECPR), prior to transport for cardiac catheterization.

[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.

Evaluation of extracorporeal cardiopulmonary resuscitation eligibility criteria for out-of-hospital cardiac arrest patients

Objectives

To evaluate the number of out-of-hospital cardiac arrest (OHCA) patients eligible for extracorporeal cardiopulmonary resuscitation (ECPR) in Saskatchewan and their clinical outcomes, including survival and neurological outcomes at discharge. ECPR eligibility was assessed, using clinical criteria from the University of British Columbia (UBC, Canada), University of Michigan (UM, United States), University of California (UC, United States) and a restrictive ECPR criteria.

Results

We performed a retrospective cohort study of 200 OHCA patients (August 1, 2017-May 31, 2019) in Regina, Saskatchewan. Sixty-one (30%) were female, the median age was 64 years (interquartile range [IQR], 52–78), the median CPR duration was 30 min (IQR 12–47), and 20% survived to discharge. Two (1%) patients received ECPR but did not meet any ECPR criteria. Nineteen (10%), thirty (15%), twenty-two (11%), and seven (4%) patients were ECPR-eligible, using the UBC, UM, UC, and restrictive criteria. However, none of these patients had received ECPR. Only two (11%), two (7%), two (9%), and one (14%) of these patient(s) survived to discharge, respectively. Neurological outcomes were unfavourable among all ECPR-eligible patients. Future study at our centre will be necessary on how to implement ECPR program to further improve these outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05564-1.

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.

Current Use, Capacity, and Perceived Barriers to the Use of Extracorporeal Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest in Canada

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is a therapeutic option for refractory cardiac arrest. We sought to perform an environmental scan to describe ECPR utilization in Canada and perceived barriers for application to out-of-hospital cardiac arrest (OHCA).

METHODS

This was a national cross-sectional study. We identified all cardiovascular surgery- and extracorporeal membrane oxygenation (ECMO)-capable hospitals in Canada and emergency medical services (EMS) agencies delivering patients to those centres. We requested the medical lead from each hospital's ECMO service and each EMS agency to submit data regarding ECMO and ECPR utilization, as well as perceived barriers to ECPR provision for OHCA.

RESULTS

We identified and received survey data from 39 of 39 Canadian hospital institutions and 21 of 22 EMS agencies. Of hospitals, 38 (97%) perform ECMO and 27 (69%) perform ECPR (74% of which perform ≤5 cases per year). Of the 18 (46%) sites offering ECPR for OHCA, 8 apply a formal protocol for eligibility and initiation procedures. EMS agencies demonstrate heterogeneity with intra-arrest transport practices. The primary rationale for nontransport of refractory OHCA is that hospital-based care offers no additional therapies. Perceived barriers to the use of ECPR for OHCA were primarily related to limited evidence supporting its use, rather than resources required.

CONCLUSION

Many Canadian cardiovascular surgery- or ECMO-equipped hospitals use ECPR; roughly half employ ECPR for OHCAs. Low case volumes and few formal protocols indicate that this is not a standardized therapy option in most centres. Increased application may be dependent on a stronger evidence base including data from randomized clinical trials currently underway.

Prognostic value of signs of life throughout cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest

PURPOSE

Prognostication of refractory out-of-hospital cardiac arrest (OHCA) is essential for selecting the population that may benefit from extracorporeal cardiopulmonary resuscitation (ECPR). We aimed to examine the prognostic value of signs of life before or throughout conventional CPR for individuals undergoing ECPR for refractory OHCA.

METHODS

Pooling the original data from three cohort studies, we estimated the prevalence of signs of life, for individuals with refractory OHCA resuscitated with ECPR. We performed multivariable logistic regression to examine the independent associations between the occurrence of signs of life and 30-day survival with a CPC score ≤ 2.

RESULTS

The analytical sample consisted of 434 ECPR recipients. The prevalence of any sign of life was 61%, including pupillary light reaction (48%), gasping (32%), or increased level of consciousness (13%). Thirty-day survival with favorable neurological outcome was 15% (63/434). In multivariable analysis, the adjusted odds ratios of 30-day survival with favorable neurological outcome were 7.35 (95% confidence interval [CI], 2.71-19.97), 5.86 (95% CI, 2.28-15.06), 4.79 (95% CI, 2.16-10.63), and 1.75 (95% CI, 0.95-3.21) for any sign of life, pupillary light reaction, increased level of consciousness, and gasping, respectively.

CONCLUSION

The assessment of signs of life before or throughout CPR substantially improves the accuracy of a multivariable prognostic model in predicting 30-day survival with favorable neurological outcome. The lack of any sign of life might obviate the provision of ECPR for patients without shockable cardiac rhythm.

Extracorporeal cardiopulmonary resuscitation for cardiac arrest

PURPOSE OF REVIEW

Extracorporeal cardiopulmonary resuscitation (ECPR) is a contemporary resuscitation approach that employs veno-arterial extracorporeal membrane oxygenation (VA-ECMO). This approach is increasingly used worldwide to mitigate the widespread hemodynamic and multiorgan dysfunction that accompanies cardiac arrest.

RECENT FINDINGS

In this review, the physiology of VA-ECMO and ECPR, the role of ECPR in contemporary resuscitation care, the complications associated with ECPR and VA-ECMO usage, and intensive care considerations for this population are discussed.

SUMMARY

ECPR offers a promising mechanism to mitigate multiorgan injury and allow time for the institution of supportive interventions required to effectively treat cardiac arrest. More prospective data in the context of extensive prehospital and hospital collaboration is needed to promote its successful use.

Association of Intra-arrest Transport vs Continued On-Scene Resuscitation With Survival to Hospital Discharge Among Patients With Out-of-Hospital Cardiac Arrest

Importance

There is wide variability among emergency medical systems (EMS) with respect to transport to hospital during out-of-hospital cardiac arrest (OHCA) resuscitative efforts. The benefit of intra-arrest transport during resuscitation compared with continued on-scene resuscitation is unclear.

Objective

To determine whether intra-arrest transport compared with continued on-scene resuscitation is associated with survival to hospital discharge among patients experiencing OHCA.

Design, Setting, and Participants

Cohort study of prospectively collected consecutive nontraumatic adult EMS-treated OHCA data from the Resuscitation Outcomes Consortium (ROC) Cardiac Epidemiologic Registry (enrollment, April 2011-June 2015 from 10 North American sites; follow-up until the date of hospital discharge or death [regardless of when either event occurred]). Patients treated with intra-arrest transport (exposed) were matched with patients in refractory arrest (at risk of intra-arrest transport) at that same time (unexposed), using a time-dependent propensity score. Subgroups categorized by initial cardiac rhythm and EMS-witnessed cardiac arrests were analyzed.

Exposures

Intra-arrest transport (transport initiated prior to return of spontaneous circulation), compared with continued on-scene resuscitation.

Main Outcomes and Measures

The primary outcome was survival to hospital discharge, and the secondary outcome was survival with favorable neurological outcome (modified Rankin scale <3) at hospital discharge.

Results

The full cohort included 43 969 patients with a median age of 67 years (interquartile range, 55-80), 37% were women, 86% of cardiac arrests occurred in a private location, 49% were bystander- or EMS-witnessed, 22% had initial shockable rhythms, 97% were treated by out-of-hospital advanced life support, and 26% underwent intra-arrest transport. Survival to hospital discharge was 3.8% for patients who underwent intra-arrest transport and 12.6% for those who received on-scene resuscitation. In the propensity-matched cohort, which included 27 705 patients, survival to hospital discharge occurred in 4.0% of patients who underwent intra-arrest transport vs 8.5% who received on-scene resuscitation (risk difference, 4.6% [95% CI, 4.0%- 5.1%]). Favorable neurological outcome occurred in 2.9% of patients who underwent intra-arrest transport vs 7.1% who received on-scene resuscitation (risk difference, 4.2% [95% CI, 3.5%-4.9%]). Subgroups of initial shockable and nonshockable rhythms as well as EMS-witnessed and unwitnessed cardiac arrests all had a significant association between intra-arrest transport and lower probability of survival to hospital discharge.

Conclusions and Relevance

Among patients experiencing out-of-hospital cardiac arrest, intra-arrest transport to hospital compared with continued on-scene resuscitation was associated with lower probability of survival to hospital discharge. Study findings are limited by potential confounding due to observational design.

Prognostic Impact of No-Flow Time on 30-Day Neurological Outcomes in Patients With Out-of-Hospital Cardiac Arrest Who Received Extracorporeal Cardiopulmonary Resuscitation

BACKGROUND

How the time sequence of cardiopulmonary resuscitation (CPR) procedures is related to clinical outcomes in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. This study examined the impact of the time interval from collapse to start of CPR (no-flow time, NF time) and the time interval from start of CPR to implementation of extracorporeal CPR (ECPR) (low-flow time, LF time) on neurological outcomes.

METHODS AND RESULTS

During the period from 2010 to 2015, we enrolled 85 patients who received ECPR. Fourteen patients (16.5%) showed favorable 30-day neurological recovery. NF time was shorter in the favorable neurological recovery group than in the unfavorable recovery group (1.4±3.0 vs. 5.2±5.8 min, P<0.05), though combined NF+LF times were similar in the 2 groups (50.1±13.2 vs. 55.1±14.8 min, P=0.25). Multivariate logistic regression analysis indicated that pupil diameter at arrival and NF time were independently associated with favorable neurological recovery. The optimal cut-off value of NF time to predict favorable neurological recovery was 5 min (area under curve: 0.70, P<0.05; sensitivity, 85.7%; specificity, 52.1%).

CONCLUSIONS

The results suggest that NF time is a better predictor than NF+LF time for neurological outcomes in OHCA patients who received ECPR, and that start of CPR within 5 min after collapse is crucial for improving neurological outcomes followed by use of ECPR.

Can we predict patient outcome before extracorporeal membrane oxygenation for refractory cardiac arrest?

Background

Refractory cardiac arrest resistant to conventional cardiopulmonary resuscitation (C-CPR) has a poor outcome. Although previous reports showed that extracorporeal cardiopulmonary resuscitation (E-CPR) can improve the clinical outcome, there are no clinically applicable predictors of patient outcome that can be used prior to the implementation of E-CPR. We aimed to evaluate the use of clinical factors in patients with refractory cardiac arrest undergoing E-CPR to predict patient outcome in our institution.

Methods

This is a single-center retrospective study. We report 112 patients presenting with refractory cardiac arrest resistant to C-CPR between January 2012 and November 2017. All patients received E-CPR for continued life support when a cardiogenic etiology was presumed. Clinical factors associated with patient outcome were analyzed. Significant pre-ECMO clinical factors were extracted to build a patient outcome risk prediction model.

Results

The overall survival rate at discharge was 40.2, and 30.4% of patients were discharged with good neurologic function. The six-month survival rate after hospital discharge was 36.6, and 25.9% of patients had good neurologic function 6 months after discharge. We stratified the patients into low-risk (n = 38), medium-risk (n = 47), and high-risk groups (n = 27) according to the TLR score (low-flow Time, cardiac arrest Location, and initial cardiac arrest Rhythm) that we derived from pre-ECMO clinical parameters. Compared with the medium-risk and high-risk groups, the low-risk group had better survival at discharge (65.8% vs. 42.6% vs. 0%, p < 0.0001) and at 6 months (60.5% vs. 38.3% vs. 0%, p = 0.0001). The low-risk group also had a better neurologic outcome at discharge (50% vs. 31.9% vs. 0%, p = 0.0001) and 6 months after discharge (44.7% vs. 25.5% vs. 0%, p = 0.0003) than the medium-risk and high-risk groups.

Conclusions

Patients with refractory cardiac arrest receiving E-CPR can be stratified by pre-ECMO clinical factors to predict the clinical outcome. Larger-scale studies are required to validate our observations.

Shortening of low-flow duration over time was associated with improved outcomes of extracorporeal cardiopulmonary resuscitation in in-hospital cardiac arrest

Introduction

Quality improvement in the administration of extracorporeal cardiopulmonary resuscitation (ECPR) over time and its association with low-flow duration (LFD) and outcomes of cardiac arrest (CA) have been insufficiently investigated. In this study, we hypothesized that quality improvement in efforts to shorten the duration of initiating ECPR had decreased LFD over the last 15 years of experience at an academic tertiary care hospital, which in turn improved the outcomes of in-hospital CA (IHCA).

Methods

This was a single-center retrospective observational study of ECPR patients between January 2003 and December 2017. A rapid response system (RRS) and an extracorporeal membrane oxygenation (ECMO) program were initiated in 2011 and 2013. First, the association of LFD per minute with the 90-day mortality and neurological outcome was analyzed using multiple logistic regression analysis. Then, the temporal changes in LFD were investigated.

Results

Of 175 study subjects who received ECPR, 117 had IHCA. In the multivariate logistic regression, IHCA patients with shorter LFD experienced significantly increased 90-day survival and favorable neurological outcomes (LFD per minute, 90-day survival: odds ratio [OR] = 0.97, 95% confidence interval [CI] = 0.94–1.00, P = 0.032; 90-day favorable neurological outcome: OR = 0.97, 95% CI = 0.94–1.00, P = 0.049). In the study period, LFD significantly decreased over time (slope − 5.39 [min/3 years], P < 0.0001).

Conclusion

A shorter LFD was associated with increased 90-day survival and favorable neurological outcomes of IHCA patients who received ECPR. The quality improvement in administering ECPR over time, including the RRS program and the ECMO program, appeared to ameliorate clinical outcomes.

In-Depth Extracorporeal Cardiopulmonary Resuscitation in Adult Out-of-Hospital Cardiac Arrest

The use of extracorporeal cardiopulmonary resuscitation (E‐CPR) for the treatment of patients with out‐of‐hospital cardiac arrest who do not respond to conventional cardiopulmonary resuscitation CPR) has increased significantly in the past 10 years, in response to case reports and observational studies reporting encouraging results. However, no randomized controlled trials comparing E‐CPR with conventional CPR have been published to date. The evidence from systematic reviews of the available observational studies is conflicting. The inclusion criteria for published E‐CPR studies are variable, but most commonly include witnessed arrest, immediate bystander CPR, an initial shockable rhythm, and an estimated time from CPR start to establishment of E‐CPR (low‐flow time) of <60 minutes. A shorter low‐flow time has been consistently associated with improved survival. In an effort to reduce low‐flow times, commencement of E‐CPR in the prehospital setting has been reported and is currently under investigation. The provision of an E‐CPR service, whether hospital based or prehospital, carries considerable cost and technical challenges. Despite increased adoption, many questions remain as to which patients will derive the most benefit from E‐CPR, when and where to implement E‐CPR, optimal post‐arrest E‐CPR care, and whether this complex invasive intervention is cost‐effective. Results of ongoing trials are awaited to determine whether E‐CPR improves survival when compared with conventional CPR.

Patient and Institutional Characteristics Influence the Decision to Use Extracorporeal Cardiopulmonary Resuscitation for In-Hospital Cardiac Arrest

BACKGROUND

Outcomes from extracorporeal cardiopulmonary resuscitation (ECPR) are felt to be influenced by selective use, but the characteristics of those receiving ECPR are undefined. We demonstrate the relationship between individual patient and hospital characteristics and the probability of ECPR use.

METHODS AND RESULTS

We performed an observational analysis of adult inpatient cardiac arrests in the United States from 2000 to 2018 reported to the American Heart Association's Get With The Guidelines—Resuscitation registry restricted to hospitals that provided ECPR. We calculated case mix adjusted relative risk (RR) of receiving ECPR for individual characteristics. From 2000 to 2018, 129 736 patients had a cardiac arrest (128 654 conventional cardiopulmonary resuscitation and 1082 ECPR) in 224 hospitals that offered ECPR. ECPR use was associated with younger age (RR, 1.5 for <40 vs. 40–59 years; 95% CI, 1.2–1.8), no pre‐existing comorbidities (RR, 1.4; 95% CI, 1.1–1.8) or cardiac‐specific comorbidities (congestive heart failure [RR, 1.3; 95% CI, 1.2–1.5], prior myocardial infarction [RR, 1.4; 95% CI, 1.2–1.6], or current myocardial infarction [RR, 1.5; 95% CI, 1.3–1.8]), and in locations of procedural areas at the times of cardiac arrest (RR, 12.0; 95% CI, 9.5–15.1). ECPR decreased after hours (3–11 pm [RR, 0.8; 95% CI, 0.7–1.0] and 11 pm–7 am [RR, 0.6; 95% CI, 0.5–0.7]) and on weekends (RR, 0.7; 95% CI, 0.6–0.9).

CONCLUSIONS

Less than 1% of in‐hospital cardiac arrest patients are treated with ECPR. ECPR use is influenced by patient age, comorbidities, and hospital system factors. Randomized controlled trials are needed to better define the patients in whom ECPR may provide a benefit.

Transesophageal Echocardiography During Cardiopulmonary Resuscitation (CPR-TEE)

BACKGROUND

To take full advantage of transesophageal echocardiography (TEE) during cardiopulmonary resuscitation (CPR), we propose a flowchart derived from representative cases.

METHODS AND RESULTS

TEE was used in patients requiring CPR to obtain information potentially helpful for rescue. TEE navigated the CPR procedures (navigation TEE), identified the possible cause of arrest (focus TEE), and optimized treatment while checking for pitfalls (secure TEE). In addition, TEE corrected prehospital misdiagnoses and detected new complications caused by CPR.

CONCLUSIONS

TEE provides valuable information without interrupting CPR procedures. It is hoped that our flowchart may facilitate goal-directed, efficient assessment.

Veno-Arterial Extracorporeal Membrane Oxygenation for Cardiogenic Shock

Extracorporeal membrane oxygenation has evolved, from a therapy that was selectively applied in the pediatric population in tertiary centers, to more widespread use in diverse forms of cardiopulmonary failure in all ages. We provide a practical review for cardiovascular clinicians on the application of veno-arterial extracorporeal membrane oxygenation in adult patients with cardiogenic shock, including epidemiology of cardiogenic shock, indications, contraindications, and the extracorporeal membrane oxygenation circuit. We also summarize cannulation techniques, practical management and troubleshooting, prognosis, and weaning and exit strategies, with attention to end of life and ethical considerations.

Management of Out-of-Hospital Cardiac Arrest Complicating Acute Coronary Syndromes

PURPOSE OF THE REVIEW

Out-of-hospital cardiac arrest (OHCA) complicating acute coronary syndromes (ACS) continues to carry a high rate of morbidity and mortality despite significant advances in EMS and interventional cardiology services. In this review, we discuss an evidence-based approach to the initial care and management of patients with OHCA complicating ACS from the pre-hospital response and initial resuscitation strategy, to advanced therapies such as coronary angiography, targeted-temperature management, neuro-prognostication, and care of the post-arrest patient.

RECENT FINDINGS

Early recognition of cardiac arrest and prompt initiation of bystander CPR are the most important factors associated with improved survival. A comprehensive and coordinated approach to in-hospital management, including PCI, targeted temperature management, critical care, and hemodynamic support represents a significant critical link in the chain of survival. OHCA complicated by ACS continues to be one of the most challenging disease states facing healthcare practitioners and maintains a high mortality rate despite substantial advancements in healthcare delivery. A comprehensive approach to in-hospital management and further exploration of novel interventions, including ECMO, may yield opportunities to optimize care and improve outcomes for cardiac arrest patients.

Medical Optimization and Liberation of Adult Patients From VA-ECMO

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) can be an efficacious cardiopulmonary support for adults as rescue from refractory cardiogenic shock. It is best employed as a bridging strategy to recovery or alternative support rather than sustained, long-term mechanical circulatory support. The purpose of this paper is to discuss strategies to optimize patient management on VA-ECMO and approaches to promote successful separation from support. Rapid medical optimization will assist in reducing the time on VA-ECMO, thereby improving the likelihood of patient salvage. Suitably trained physicians and personnel, guided by structured protocols, can promote excellence in team care and provision of consistent management. Focusing on anticoagulation, careful neurologic monitoring, prevention of leg ischemia, awareness of differential hypoxemia, optimizing mechanical ventilation, identifying and timely intervention for left-ventricular distension (LVD), along with a strategic weaning algorithm, can prevent significant morbidity and mortality. LVD physiology, diagnosis, and risk factors are reviewed. Indications for LV decompression, along with medical and mechanical management options, are elucidated.

Perfusion parameters and target values during extracorporeal cardiopulmonary resuscitation: a scoping review protocol

INTRODUCTION

Extracorporeal cardiopulmonary resuscitation (eCPR) is increasingly applied in out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA) patients. Treatment results are promising, but the efficacy and safety of the procedure are still unclear. Currently, there are no recommended target perfusion parameters during eCPR, the lack of which could result in inadequate (re)perfusion. We aim to perform a scoping review to explore the current literature addressing target perfusion parameters, target values, corresponding survival rates and neurologic outcomes in OHCA and IHCA patients treated with eCPR.

METHODS AND ANALYSIS

To identify relevant research, we will conduct searches in the electronic databases MEDLINE, EMBASE, Social Science Citation Index, Social Science Citation Index Expanded and the Cochrane library. We will also check references of relevant articles and perform a cited reference research (forward citation tracking).Two independent reviewers will screen titles and abstracts, check full texts for eligibility and perform data extraction. We will resolve dissent by consensus, moderated by a third reviewer. We will include observational and controlled studies addressing target perfusion parameters and outcomes such as survival rates and neurologic findings in OHCA and IHCA patients treated with eCPR. Data extraction tables will be set up, including study and patients' characteristics, aim of study, details on eCPR including target perfusion parameters and reported outcomes. We will summarise the data using tables and figures (ie, bubble plot) to present the research landscape and to describe potential clusters and/or gaps.

ETHICS AND DISSEMINATION

An ethical approval is not needed. We intend to publish the scoping review in a peer-reviewed journal and present results on a scientific meeting.

Prognostic Value of Blood Lactate and Base Deficit in Refractory Cardiac Arrest Cases Undergoing Extracorporeal Life Support

Objective

Cardiac arrest (CA) resuscitation is associated with an 'ischaemia-reperfusion' syndrome characterised by lactic acidosis as assessed by lactate and base deficit (BD). Both biomarkers are usually measured in patients suffering from refractory CA (RCA) subjected to extracorporeal life support (ECLS) to evaluate tissue reperfusion. However, their prognostic value has never been compared. The aim of the present study was to compare the prognostic value of both biomarkers measured at 0 and 3 h after the initiation of ECLS in patients with RCA on mortality.

Methods

Patients who were admitted to the intensive care unit with RCA were consecutively included in the study.

Results

Sixty-six patients were included. Lactate correlated with BD (R2=0.44, p<0.001). An area under the curve of 0.72 (95% confidence interval (CI) 0.59-0.84) was found for lactate and of 0.60 (95% CI 0.46-0.73) for BD. Using multivariable logistic regression, lactate (odds ratio (OR) 1.22, 95% CI 1.03-1.48) remained associated with mortality on day 28, but not BD (OR 0.99, 95% CI 0.86-1.14).

Conclusion

We report a difference in the prognostic value of lactate and BD on mortality. Three hours from the initiation of ECLS in patients with RCA, lactate should be preferred to BD to predict the efficiency of ECLS.

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.

[Organ assist devices in the future : Limits and perspectives]

In the last decade, extracorporeal organ assist devices (extracorporeal membrane oxygenation [ECMO]) have been increasingly applied to treat the most severe forms of respiratory failure and cardiogenic shock, although the underlying scientific evidence is still limited and the methods carry a high risk of complications despite all technical improvements. The selection of those patients who most benefit from these devices is still a great challenge for intensivists and all other involved disciplines. Besides the severity of the acute organ failure, it is important to thoroughly evaluate etiology and treatment options of the underlying disease, comorbidities, and the functional status of the patients in an interdisciplinary team. This also includes ethical challenges. Because of the complexity of the treatment and the high organizational demands it is reasonable to concentrate ECMO treatments in specifically qualified centers and to promote a comprehensive scientific analysis of the treatment data.