Extracorporeal cardiopulmonary resuscitation in adults and children: A review of literature, published guidelines and pediatric single-center program building experience

Extracorporeal cardiopulmonary resuscitation (ECPR) is an adjunct supportive therapy to conventional cardiopulmonary resuscitation (CCPR) employing veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in the setting of refractory cardiac arrest. Its use has seen a significant increase in the past decade, providing hope for good functional recovery to patients with cardiac arrest refractory to conventional resuscitation maneuvers. This review paper aims to summarize key findings from the ECPR literature available to date as well as the recommendations for ECPR set forth by leading national and international resuscitation societies. Additionally, we describe the successful pediatric ECPR program at Texas Children's Hospital, highlighting the logistical, technical and educational features of the program.

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.

Neurological outcome after extracorporeal cardiopulmonary resuscitation for in-hospital cardiac arrest: a systematic review and meta-analysis

BACKGROUND

In-hospital cardiac arrest (IHCA) is a major adverse event with a high mortality rate if not treated appropriately. Extracorporeal cardiopulmonary resuscitation (ECPR), as adjunct to conventional cardiopulmonary resuscitation (CCPR), is a promising technique for IHCA treatment. Evidence pertaining to neurological outcomes after ECPR is still scarce.

METHODS

We performed a comprehensive systematic search of all studies up to December 20, 2019. Our primary outcome was neurological outcome after ECPR at any moment after hospital discharge, defined by the Cerebral Performance Category (CPC) score. A score of 1 or 2 was defined as favourable outcome. Our secondary outcome was post-discharge mortality. A fixed-effects meta-analysis was performed.

RESULTS

Our search yielded 1215 results, of which 19 studies were included in this systematic review. The average survival rate was 30% (95% CI 28-33%, I2 = 0%, p = 0.24). In the surviving patients, the pooled percentage of favourable neurological outcome was 84% (95% CI 80-88%, I2 = 24%, p = 0.90).

CONCLUSION

ECPR as treatment for in-hospital cardiac arrest is associated with a large proportion of patients with good neurological outcome. The large proportion of favourable outcome could potentially be explained by the selection of patients for treatment using ECPR. Moreover, survival is higher than described in the conventional CPR literature. As indications for ECPR might extend to older or more fragile patient populations in the future, research should focus on increasing survival, while maintaining optimal neurological outcome.

Veno-arterial-ECMO in the intensive care unit: From technical aspects to clinical practice

The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) as a salvage therapy in cardiogenic shock is becoming of current practice. While VA-ECMO is potentially a life-saving technique, results are sometimes mitigated, emphasising the need for selecting the right indication in the right patient. This relies upon a clear definition of the individual therapeutic project, including the potential for recovery as well as the possible complications associated with VA-ECMO. To maximise the benefits of VA-ECMO, the basics of extracorporeal circulation should be perfectly understood since VA-ECMO can sometimes be detrimental. Hence, to be successful, VA-ECMO should be used by teams with sufficient experience and initiated after a thorough multidisciplinary discussion considering patient's medical history, pathology as well the anticipated evolution of the disease.

Current and Future Status of Extracorporeal Cardiopulmonary Resuscitation for In-Hospital Cardiac Arrest

Numerous series, propensity-matched trials, and meta-analyses suggest that appropriate use of extracorporeal cardiopulmonary resuscitation (E-CPR) for in-hospital cardiac arrest (IHCA) can be lifesaving. Even with an antecedent cardiopulmonary resuscitation (CPR) duration in excess of 45 minutes, 30-day survival with favourable neurologic outcome using E-CPR is approximately 35%-45%. Survival may be related to age, duration of CPR, or etiology. Associated complications include sepsis, renal failure, limb and neurologic complications, hemorrhage, and thrombosis. However, methodological biases-including small sample size, selection bias, publication bias, and inability to control for confounders-in these series prevent definitive conclusions. As such, the 2015 American Heart Association Advanced Cardiac Life Support guidelines update recommended E-CPR as a Level of Evidence IIb recommendation in appropriate cases. The absence of high-quality evidence presents an opportunity for clinician/scientists to generate practice-defining data through collaborative investigation and prospective trials. A multidisciplinary dialogue is required to standardize the field and promote multicentre investigation of E-CPR with data sharing and the development of a foundation for high-quality trials. The objectives of this review are to (1) provide an overview of the strengths and limitations of currently available studies investigating the use of E-CPR in patients with IHCA and highlight knowledge gaps; (2) create a framework for the standardization of terminology, clinical practice, data collection, and investigation of E-CPR for patients with IHCA that will help ensure congruence in future work in this area; and (3) propose suggestions to guide future research by the cardiovascular community to advance this important field.

Extracorporeal Membrane Oxygenation Applications in Cardiac Critical Care

The use of extracorporeal membrane oxygenation therapy (ECMO) in cardiac critical care has steadily increased over the past decade. Significant improvements in the technology associated with ECMO have propagated this recent resurgence and contributed to improved patient outcomes in the fields of cardiac and transplant (heart and lung) surgery. Specifically, ECMO is being increasingly utilized as a bridge to heart and lung transplantation, as well as to ventricular assist device placement. ECMO is also employed during the administration of cardiopulmonary resuscitation, known as extracorporeal life support. In this review, we examine the recent literature regarding the applications of ECMO and also describe emerging topics involving current ECMO management strategies.

Extracorporeal membrane oxygenation use, expenditure, and outcomes in taiwan from 2000 to 2010

Background

No study to date has systematically examined use, expenditure, and outcomes associated with extracorporeal membrane oxygenation (ECMO) use in Taiwan. The aim of this study was to examine ECMO use, expenditure, and outcomes during an 11-year period in Taiwan.

Methods

Claims data were collected from the Taiwan National Health Insurance Research Database for patients who received ≥1 ECMO treatment between January 2000 and December 2010. Measurements included demographics, indications for ECMO use, length of hospital stay, outcome, and expenditure.

Results

A total of 3969 patients received ECMO during the study period (median age: 54.6 years). The number of patients receiving ECMO increased from 52 in 2000 to 1045 in 2010. The major indication for ECMO was cardiovascular disease (68.7%), followed by respiratory disease (17.9%). Median length of hospital stay was 13 days in 2000 and 17 days in 2010. Median expenditure (New Taiwan dollars) was $604 317 in 2000 and $673 888 in 2010. Some variables significantly differed by age, sex, hospital setting, calendar year, and indication for ECMO, and were associated with in-hospital and after-discharge mortality.

Conclusions

ECMO use has increased dramatically in Taiwan over the last decade. The high mortality rate of ECMO users suggested that ECMO may be being used in Taiwan for situations in which it provides no added benefit. This situation may be a reflection of the current reimbursement criteria for National Health Insurance in Taiwan. Refinement of the indications for use of ECMO is suggested.

The State of the Art in Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation has evolved in design, technology, patient selection, insertion techniques, adjunct devices, and management in the past 45 years since it began. Outcomes have improved and indications have expanded. It continues to be an expeditious, cost-effective tool for rapid resuscitation of patients with cardiorespiratory failure, whose outcomes without extracorporeal membrane oxygenation intervention are predominately fatal. However, results are still moderately satisfactory, and the ethical aspects of ongoing care need to be at the forefront of daily family discussions in patients for whom a bridge to transplant or definitive device is not possible.

Extracorporeal cardiopulmonary resuscitation

PURPOSE OF REVIEW

To discuss the role of extracorporeal membrane oxygenation (ECMO) in patients with cardiac arrest.

RECENT FINDINGS

Return to spontaneous circulation dramatically decreases with the duration of cardiopulmonary resuscitation (CPR). In this context, it has been proposed to implement venoarterial ECMO in order to assist CPR (ECPR) both in inhospital cardiac arrest (IHCA) and in out-of-hospital cardiac arrest (OHCA).

SUMMARY

This review highlights that ECPR is feasible for both IHCA and OHCA. In the recent series, the outcome of ECPR in IHCA is satisfactory, with survival rates good with neurologic outcome reaching the 40-50% range. All series converge in highlighting that time from cardiac arrest to ECMO flow is a critical determinant of outcome, with survival rates of 50% when initiated within 30 min of IHCA, 30% between 30 and 60 min, and 18% after 60 min. Results of ECPR in OHCA are more challenging. Recent series suggest that good outcome can be obtained in 15-20% of the patients, provided that time from arrest to ECMO is shorter than 60 min. Duration of cardiac arrest seems to be more important than location of cardiac arrest. ECPR thus seems to be a valuable option in selected cases.

Venoarterial extracorporeal membrane oxygenation for cardiogenic shock and cardiac arrest: a meta-analysis

OBJECTIVE

To evaluate the effect of extracorporeal membrane oxygenation (ECMO) on survival and complication rates in adults with refractory cardiogenic shock or cardiac arrest.

DESIGN

Meta-analysis.

SETTING

University hospitals.

PARTICIPANTS

One thousand one hundred ninety-nine patients from 22 observational studies.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Observational studies published from the year 2000 onwards, examining at least 10 adult patients who received ECMO for refractory cardiogenic shock or cardiac arrest were included. Pooled estimates with 95% confidence intervals were calculated based on the Freeman-Tukey double-arcsine transformation and DerSimonian-Laird random-effect model. Survival to discharge was 40.2% (95% confidence intervals [CI], 33.9-46.7), while survival at 3, 6, and 12 months was 55.9% (95% CI, 41.5-69.8), 47.6% (95% CI, 25.4-70.2), and 54.4% (95% CI, 36.6-71.7), respectively. Survival up to 30 days was higher in cardiogenic shock patients (52.5%, 95% CI, 43.7%-61.2%) compared to cardiac arrest (36.2%, 95% CI, 23.1%-50.4%). Concurrently, complication rates were particularly substantial for neurologic deficits (13.3%, 95% CI, 8.3-19.3), infection (25.1%, 95%CI, 15.9-35.5), and renal impairment (47.4%, 95% CI, 30.2-64.9). Significant heterogeneity was detected, although its levels were similar to previous meta-analyses that only examined short-term survival to discharge.

CONCLUSIONS

Venoarterial ECMO can improve short-term survival in adults with refractory cardiogenic shock or cardiac arrest. It also may provide favorable long-term survival at up to 3 years postdischarge. However, ECMO also is associated with significant complication rates, which must be incorporated into the risk-benefit analysis when considering treatment. These findings require confirmation by large, adequately controlled and standardized trials with long-term follow-up.

Median frequencies of prolonged ventricular fibrillation treated by V-A ECMO correspond to a return of spontaneous circulation rate

BACKGROUND

The aim of our study was to analyze, in a pig model of prolonged ventricular fibrillation (VF) treated by veno-arterial extracorporeal membrane oxygenation (ECMO), the time dependent changes of VF wavelet frequency obtained from intracardial signals and its relations to return of spontaneous circulation (ROSC).

METHODS

11 female pigs (50.3 ± 3.4 kg) under general anesthesia had undergone 15 min of VF with ECMO flow of 5 to 10 ml/kg per min simulating "untreated" VF followed by continued VF with full ECMO flow of 100 ml/kg per min. The median frequency (MF) of VF from right ventricular apex, coronary perfusion pressure, myocardial oxygen metabolism and resuscitability were determined.

RESULTS

Median (interquartile range) of MF of fibrillatory wavelets in minute 15 of low ECMO flow [9.7 Hz (8.3; 10.1)] was not significantly changed in comparison to minute 1 [10.5 Hz (9.8; 12.4)], p = 0.12. Five minutes after full ECMO initiation MF increased [11.6 Hz (10.6; 13.5)], p = 0.04 (compared to minute 15 of VF) and did not deteriorate during the rest of ECMO treatment. Out of all subjects, three animals did not reach ROSC. Those subjects demonstrated deeper decrease of MF at the VF minute 15 as compared to others [-2.4 Hz (-2.5; -2.3) vs. -0.6 Hz (-1.6; -0.1)] and continuously significantly higher increase in MF on full ECMO support [4.3 Hz (2.9; 5.6) vs. 1.1 Hz (0.6; 1.6)] with p = 0.05 for both observations, respectively.

CONCLUSIONS

The veno-arterial ECMO reperfusion influences MF of VF wavelet obtained from right ventricular apex. The course of changes in wavelet frequency corresponds to a presence of later ROSC.

Venous-arterial extracorporeal membrane oxygenation for refractory cardiac arrest: a clinical challenge

Guidelines stated that extracorporeal membrane oxygenation (ECMO) may improve outcomes after refractory cardiac arrest (CA) in cases of cardiogenic shock and witnessed arrest, where there is an underlying circulatory disease amenable to immediate corrective intervention. Due to the lack of randomized trials, available data are supported by small series and observational studies, being therefore characterized by heterogeneity and controversial results. In clinical practice, using ECMO involves quite a challenging medical decision in a setting where the patient is extremely vulnerable and completely dependent on the medical team's judgment. The present review focuses on examining existing evidence concerning inclusion and exclusion criteria, and outcomes (in-hospital and long-term mortality rates and neurological recovery) in studies performed in patients with refractory CA treated with ECMO. Discrepancies can be related to heterogeneity in study population, to differences in local health system organization in respect of the management of patients with CA, as well as to the fact that most investigations are retrospective. In the real world, patient selection occurs individually within each center based on their previous experience and expertise with a specific patient population and disease spectrum. Available evidence strongly suggests that in CA patients, ECMO is a highly costly intervention and optimal utilization requires a dedicated local health-care organization and expertise in the field (both for the technical implementation of the device and for the intensive care management of these patients). A careful selection of patients guarantees optimal utilization of resources and a better outcome.

Hyperinvasive approach to out-of hospital cardiac arrest using mechanical chest compression device, prehospital intraarrest cooling, extracorporeal life support and early invasive assessment compared to standard of care. A randomized parallel groups comparative study proposal. "Prague OHCA study"

Background

Out of hospital cardiac arrest (OHCA) has a poor outcome. Recent non-randomized studies of ECLS (extracorporeal life support) in OHCA suggested further prospective multicenter studies to define population that would benefit from ECLS. We aim to perform a prospective randomized study comparing prehospital intraarrest hypothermia combined with mechanical chest compression device, intrahospital ECLS and early invasive investigation and treatment in all patients with OHCA of presumed cardiac origin compared to a standard of care.

Methods

This paper describes methodology and design of the proposed trial. Patients with witnessed OHCA without ROSC (return of spontaneous circulation) after a minimum of 5 minutes of ACLS (advanced cardiac life support) by emergency medical service (EMS) team and after performance of all initial procedures (defibrillation, airway management, intravenous access establishment) will be randomized to standard vs. hyperinvasive arm. In hyperinvasive arm, mechanical compression device together with intranasal evaporative cooling will be instituted and patients will be transferred directly to cardiac center under ongoing CPR (cardiopulmonary resuscitation). After admission, ECLS inclusion/exclusion criteria will be evaluated and if achieved, veno-arterial ECLS will be started. Invasive investigation and standard post resuscitation care will follow. Patients in standard arm will be managed on scene. When ROSC achieved, they will be transferred to cardiac center and further treated as per recent guidelines.

Primary outcome

6 months survival with good neurological outcome (Cerebral Performance Category 1–2). Secondary outcomes will include 30 day neurological and cardiac recovery.

Discussion

Authors introduce and offer a protocol of a proposed randomized study comparing a combined “hyperinvasive approach” to a standard of care in refractory OHCA. The protocol is opened for sharing by other cardiac centers with available ECLS and cathlab teams trained to admit patients with refractory cardiac arrest under ongoing CPR. A prove of concept study will be started soon. The aim of the authors is to establish a net of centers for a multicenter trial initiation in future.

Ethics and registration

The protocol has been approved by an Institutional Review Board, will be supported by a research grant from Internal Grant Agency of the Ministry of Health, Czech Republic NT 13225-4/2012 and has been registered under ClinicalTrials.gov identifier: NCT01511666.