Traumatic and hemorrhagic complications after extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest

Impact of extracorporeal cardiopulmonary resuscitation on neurological prognosis and survival in adult patients after cardiac arrest: an individual pooled patient data meta-analysis

BACKGROUND

We aimed to estimate the effect of extracorporeal cardiopulmonary resuscitation (ECPR) on neurological outcome and mortality, when compared to conventional cardiopulmonary resuscitation (CCPR), using an individual patient data meta-analysis (IPDMA).

METHODS

A systematic literature search was performed up to the 20th of October 2022 in the PubMed, EMBASE and CENTRAL databases. For observational studies with unmatched populations, a propensity score including age, location of arrest and initial rhythm was used to match ECPR and CCPR patients in a 1:1 ratio. The primary and secondary outcomes were unfavorable neurological outcome (Cerebral Performance Category of 3-5) and mortality, respectively, which were both collected at different time-points.

RESULTS

Data from 17 studies, including 2064 matched cardiac arrest (CA) patients (1031 ECPR and 1033 CCPR cases) were included. In comparison to CCPR, ECPR was associated with a decreased odds of unfavorable neurological outcome (847, 82.2% vs. 897, 86.8% - OR 0.68 [95%CI 0.53-0.87]; p=0.002) and death (803, 77.9% vs. 860, 83.3% - OR 0.68 [95%CI 0.54-0.86]; p=0.001). These results were consistent across most of the prespecified subgroups. Moreover, the odds of both unfavorable neurological outcome and mortality were significantly influenced by initial rhythm, cause of arrest and combinations of lactate levels on admission and duration of resuscitation.

CONCLUSIONS

This IPDMA showed that ECPR was associated with significantly lower rates of unfavorable neurological outcome and mortality in refractory CA. The overall effect could be influenced by CA characteristics and the severity of the initial injury.

Letter to the editor: Role of extracorporeal life support for traumatic hemopericardium: A single level I trauma center review

While this study sheds light on the valuable clinical outcomes regarding the use of extracorporeal life support (ECLS) in managing traumatic hemopericardium, I would like to emphasize a few critical areas that would improve the study's findings.

Differences in outcomes of patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation between day-time and night-time

Although patients who underwent night-time resuscitation for out-of-hospital cardiac arrest (OHCA) had worse clinical outcomes than those who underwent day-time resuscitation, the differences between the outcomes of patients with OHCA who underwent extracorporeal cardiopulmonary resuscitation (ECPR) in the day-time and night-time remain unclear. We analyzed data from the Study of Advanced Life Support for Ventricular Fibrillation with Extracorporeal Circulation in Japan. Patients were categorized according to whether they received treatment during the day-time or night-time. The primary outcomes were survival to hospital discharge and favorable neurological outcome at discharge, and the secondary outcomes were estimated low-flow time, implementation time of ECPR, and complications due to ECPR. A multivariate logistic regression model adjusted for confounders was used for comparison. Among the 1644 patients, the night-time patients had a significantly longer ECMO implementation time and estimated low-flow time than the day-time patients, along with a significantly higher number of complications than the day-time patients. However, the survival and neurologically favorable survival rates did not differ significantly between the groups. Thus, although patients who underwent ECPR at night had an increased risk of longer implementation time and complications, their clinical outcomes did not differ from those who underwent day-time ECPR.

Bleeding and Thrombosis in Patients With Out-of-Hospital Ventricular Tachycardia/Ventricular Fibrillation Arrest Treated With Extracorporeal Cardiopulmonary Resuscitation

BACKGROUND

Extracorporeal cardiopulmonary resuscitation improves outcomes after out-of-hospital cardiac arrest. However, bleeding and thrombosis are common complications. We aimed to describe the incidence and predictors of bleeding and thrombosis and their association with in-hospital mortality.

METHODS AND RESULTS

Consecutive patients presenting with refractory ventricular tachycardia/ventricular fibrillation out-of-hospital cardiac arrest between December 2015 and March 2022 who met the criteria for extracorporeal cardiopulmonary resuscitation initiation at our center were included. Major bleeding was defined by the Extracorporeal Life Support Organization's criteria. Adjusted analyses were done to seek out risk factors for bleeding and thrombosis and evaluate their association with mortality. Major bleeding occurred in 135 of 200 patients (67.5%), with traumatic bleeding from cardiopulmonary resuscitation in 73 (36.5%). Baseline demographics and arrest characteristics were similar between groups. In multivariable analysis, decreasing levels of fibrinogen were independently associated with bleeding (adjusted hazard ratio [aHR], 0.98 per every 10 mg/dL rise [95% CI, 0.96-0.99]). Patients who died had a higher rate of bleeds per day (0.21 versus 0.03, P<0.001) though bleeding was not significantly associated with in-hospital death (aHR, 0.81 [95% CI. 0.55-1.19]). A thrombotic event occurred in 23.5% (47/200) of patients. Venous thromboembolism occurred in 11% (22/200) and arterial thrombi in 15.5% (31/200). Clinical characteristics were comparable between groups. In adjusted analyses, no risk factors for thrombosis were identified. Thrombosis was not associated with in-hospital death (aHR, 0.65 [95% CI, 0.42-1.03]).

CONCLUSIONS

Bleeding is a frequent complication of extracorporeal cardiopulmonary resuscitation that is associated with decreased fibrinogen levels on admission whereas thrombosis is less common. Neither bleeding nor thrombosis was significantly associated with in-hospital mortality.

Scrutinizing the Role of Venoarterial Extracorporeal Membrane Oxygenation: Has Clinical Practice Outpaced the Evidence?

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for temporary mechanical circulatory support in various clinical scenarios has been increasing consistently, despite the lack of sufficient evidence regarding its benefit and safety from adequately powered randomized controlled trials. Although the ARREST trial (Advanced Reperfusion Strategies for Patients with Out-of-Hospital Cardiac Arrest and Refractory Ventricular Fibrillation) and a secondary analysis of the PRAGUE OHCA trial (Prague Out-of-Hospital Cardiac Arrest) provided some evidence in favor of VA-ECMO in the setting of out-of-hospital cardiac arrest, the INCEPTION trial (Early Initiation of Extracorporeal Life Support in Refractory Out-of-Hospital Cardiac Arrest) has not found a relevant improvement of short-term mortality with extracorporeal cardiopulmonary resuscitation. In addition, the results of the recently published ECLS-SHOCK trial (Extracorporeal Life Support in Cardiogenic Shock) and ECMO-CS trial (Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock) discourage the routine use of VA-ECMO in patients with infarct-related cardiogenic shock. Ongoing clinical trials (ANCHOR [Assessment of ECMO in Acute Myocardial Infarction Cardiogenic Shock, NCT04184635], REVERSE [Impella CP With VA ECMO for Cardiogenic Shock, NCT03431467], UNLOAD ECMO [Left Ventricular Unloading to Improve Outcome in Cardiogenic Shock Patients on VA-ECMO, NCT05577195], PIONEER [Hemodynamic Support With ECMO and IABP in Elective Complex High-risk PCI, NCT04045873]) may clarify the usefulness of VA-ECMO in specific patient subpopulations and the efficacy of combined mechanical circulatory support strategies. Pending further data to refine patient selection and management recommendations for VA-ECMO, it remains uncertain whether the present usage of this device improves outcomes.

Implementation of Extracorporeal CPR Programs for Out-of-Hospital Cardiac Arrest: Another Tale of Two County Hospitals

Extracorporeal cardiopulmonary resuscitation (ECPR) is a form of intensive life support that has seen increasing use globally to improve outcomes for patients who experience out-of-hospital cardiac arrest (OHCA). Hospitals with advanced critical care capabilities may be interested in launching an ECPR program to offer this support to the patients they serve; however, to do so, they must first consider the significant investment of resources necessary to start and sustain the program. The existing literature describes many single-center ECPR programs and often focuses on inpatient care and patient outcomes in hospitals with cardiac surgery capabilities. However, building a successful ECPR program and using this technology to support an individual patient experiencing refractory cardiac arrest secondary to a shockable rhythm depends on efficient out-of-hospital and emergency department (ED) management. This article describes the process of implementing 2 intensivist-led ECPR programs with limited cardiac surgery capability. We focus on emergency medical services and ED clinician roles in identifying patients, mobilizing resources, initiation and management of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in the ED, and ongoing efforts to improve ECPR program quality. Each center experienced a significant learning curve to reach goals of arrest-to-flow times of cannulation for ECPR. Building consensus from multidisciplinary stakeholders, including out-of-hospital stakeholders; establishing shared expectations of ECPR outcomes; and ensuring adequate resource support for ECPR activation were all key lessons in improving our ECPR programs.

The state of emergency department extracorporeal cardiopulmonary resuscitation: Where are we now, and where are we going?

Extracorporeal cardiopulmonary resuscitation (ECPR) has emerged in the context of the emergency department as a life-saving therapy for patients with refractory cardiac arrest. This review examines the utility of ECPR based on current evidence gleaned from three pivotal trials: the ARREST trial, the Prague study, and the INCEPTION trial. We also discuss several considerations in the care of these complex patients, including prehospital strategy, patient selection, and postcardiac arrest management. Collectively, the evidence from these trials emphasizes the growing significance of ECPR as a viable intervention, highlighting its potential for improved outcomes and survival rates in patients with refractory cardiac arrest when employed judiciously. As such, these findings advocate the need for further research and protocol development to optimize its use in diverse clinical scenarios.

Venoarterial extracorporeal membrane oxygenation for cardiopulmonary resuscitation: A retrospective study comparing the outcomes of fluoroscopy

Background

Extracorporeal cardiopulmonary resuscitation (ECPR) using venoarterial extracorporeal membrane oxygenation is performed for out-of-hospital cardiac arrest; however, it is associated with a risk of several complications.

Objective

To investigate whether the fluoroscopy equipment was removed from the emergency department (ED) and whether it would be beneficial to transport the patient to the fluoroscopy room to reduce vascular complications without affecting the induction time.

Methods

This single-center, retrospective, before-and-after analysis was conducted at a tertiary emergency medical center and included 59 patients who underwent ECPR for out-of-hospital cardiac arrest between May 2017 and March 2022. The patients were divided into two groups: those who underwent cannulation in the ED without fluoroscopy (ED-ECPR group) and those who were transferred directly from the ED to the cardiac angiography room (ECPR call group).

Results

The rate of vascular complications associated with ECPR was significantly lower in the ECPR group than in the ED-ECPR group (40.6 % [14/32] vs. 10 % [2/20], respectively; p = 0.014). The duration from ED arrival to venoarterial extracorporeal membrane oxygenation initiation was similar in the two groups (median: 23.0 min in the ED-ECPR group vs. 25.5 min in the ECPR call group, p = 0.71). Results adjusted for confounding factors showed that performing ECPR under fluoroscopy was a consistent and independent element of vascular complication rates (adjusted odds ratio: 9.92, 95 % confidence interval: 2.04 to 81.2, p = 0.011).

Conclusions

Fluoroscopy-guided ECPR can significantly reduce the incidence of vascular complications even if the ED and fluoroscopy room are far apart. However, no significant difference was observed in the time required to establish ECPR in the cardiac catheterization laboratories.

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.

Extracorporeal membrane oxygenation for cardiac arrest: what, when, why, and how

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) facilitated resuscitation was first described in the 1960s, but only recently garnered increased attention with large observational studies and randomized trials evaluating its use.

AREAS COVERED

In this comprehensive review of extracorporeal cardiopulmonary resuscitation (ECPR), we report the history of resuscitative ECMO, terminology, circuit configuration and cannulation considerations, complications, selection criteria, implementation and management, and important considerations for the provider. We review the relevant guidelines, different approaches to cannulation, postresuscitation management, and expected outcomes, including neurologic, cardiac, and hospital survival. Finally, we advocate for the participation in national/international Registries in order to facilitate continuous quality improvement and support scientific discovery in this evolving area.

EXPERT OPINION

ECPR is the most disruptive technology in cardiac arrest resuscitation since high-quality CPR itself. ECPR has demonstrated that it can provide up to 30% increased odds of survival for refractory cardiac arrest, in tightly restricted systems and for select patients. It is also clear, though, from recent trials that ECPR will not confer this high survival when implemented in less tightly protocoled settings and within lower volume environments. Over the next 10 years, ECPR research will explore the optimal initiation thresholds, best practices for implementation, and postresuscitation care.

Prognostic factors associated with favourable functional outcome among adult patients requiring extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest: A systematic review and meta-analysis

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR), has demonstrated promise in the management of refractory out-of-hospital cardiac arrest (OHCA). However, evidence from observational studies and clinical trials are conflicting and the factors influencing outcome have not been well established.

METHODS

We conducted a systematic review and meta-analysis summarizing the association between pre-ECPR prognostic factors and likelihood of good functional outcome among adult patients requiring ECPR for OHCA. We searched Medline and Embase databases from inception to February 28, 2023 and screened studies with two independent reviewers. We performed meta-analyses of unadjusted and adjusted odds ratios, adjusted hazard ratios and mean differences separately. We assessed risk of bias using the QUIPS tool and certainty of evidence using the GRADE approach.

FINDINGS

We included 29 observational and randomized studies involving 7,397 patients. Factors with moderate or high certainty of association with increased survival with favourable functional outcome include pre-arrest patient factors, such as younger age (odds ratio (OR) 2.13, 95% CI 1.52 to 2.99) and female sex (OR 1.37, 95% CI 1.11 to 1.70), as well as intra-arrest factors, such as shockable rhythm (OR 2.79, 95% CI 2.04 to 3.80), witnessed arrest (OR 1.68 (95% CI 1.16 to 2.42), bystander CPR (OR 1.55, 95% CI 1.19 to 2.01), return of spontaneous circulation (OR 2.81, 95% CI 2.19 to 3.61) and shorter time to cannulation (OR 1.14, 95% CI 1.17 to 1.69 per 10 minutes).

INTERPRETATION

The findings of this review confirm several clinical concepts wellestablished in the cardiac arrest literature and their applicability to the patient for whom ECPR is considered - that is, the impact of pre-existing patient factors, the benefit of timely and effective CPR, as well as the prognostic importance of minimizing low-flow time. We advocate for the thoughtful consideration of these prognostic factors as part of a risk stratification framework when evaluating a patient's potential candidacy for ECPR.

Intraoperative cardiac arrest caused by unexpected vasospastic angina requiring prolonged resuscitation using extracorporeal membrane oxygenation: a case report

BACKGROUND

Vasospastic angina (VSA) occurring during surgery is rare but can lead to sudden intraoperative cardiac arrest.

CASE PRESENTATION

A 77-year-old man with hypertension, and no history of coronary artery disease, displayed an abrupt ST-segment elevation on the electrocardiogram (ECG) during laparoscopic inguinal hernia surgery under general anesthesia. Subsequently, ventricular fibrillation (VF) occurred, with a finding suggesting ischemic myocardial contracture by transesophageal echocardiography. VF was refractory to cardiopulmonary resuscitation (CPR), and veno-arterial extracorporeal membrane oxygenation (VA ECMO) was introduced. Spontaneous circulation resumed 77 min post-cardiac arrest. VSA was confirmed through the patient's clinical course and coronary angiography. Subsequently, VA ECMO was terminated, and the patient was discharged uneventfully.

CONCLUSIONS

Extracorporeal CPR may be a valuable alternative to extended resuscitation for refractory ventricular arrhythmias by VSA.

R. Whitman G, Cho SM. A recommended preclinical extracorporeal cardiopulmonary resuscitation model for neurological outcomes: A scoping review

Background

Despite the high prevalence of neurological complications and mortality associated with extracorporeal cardiopulmonary resuscitation (ECPR), neurologically-focused animal models are scarce. Our objective is to review current ECPR models investigating neurological outcomes and identify key elements for a recommended model.

Methods

We searched PubMed and four other engines for animal ECPR studies examining neurological outcomes. Inclusion criteria were: animals experiencing cardiac arrest, ECPR/ECMO interventions, comparisons of short versus long cardiac arrest times, and neurological outcomes.

Results

Among 20 identified ECPR animal studies (n = 442), 13 pigs, 4 dogs, and 3 rats were used. Only 10% (2/20) included both sexes. Significant heterogeneity was observed in experimental protocols. 90% (18/20) employed peripheral VA-ECMO cannulation and 55% (11/20) were survival models (median survival = 168 hours; ECMO duration = 60 minutes). Ventricular fibrillation (18/20, 90%) was the most common method for inducing cardiac arrest with a median duration of 15 minutes (IQR = 6-20). In two studies, cardiac arrests exceeding 15 minutes led to considerable mortality and neurological impairment. Among seven studies utilizing neuromonitoring tools, only four employed multimodal devices to evaluate cerebral blood flow using Transcranial Doppler ultrasound and near-infrared spectroscopy, brain tissue oxygenation, and intracranial pressure. None examined cerebral autoregulation or neurovascular coupling.

Conclusions

The substantial heterogeneity in ECPR preclinical model protocols leads to limited reproducibility and multiple challenges. The recommended model includes large animals with both sexes, standardized pre-operative protocols, a cardiac arrest time between 10-15 minutes, use of multimodal methods to evaluate neurological outcomes, and the ability to survive animals after conducting experiments.

Development of an in-vitro model for extracorporeal blood pumps to study the effects of artificial pulsatility on human blood

Introduction

The application of extracorporeal circulation (ECC) systems is known to be associated with several implications regarding hemolysis, inflammation, and coagulation. In the last years, systems with pulsatile blood flow are increasingly used with the intention to improve hemodynamics in reperfusion. However, their implications on the aforementioned aspects remain largely unknown. To investigate the effects of pulsatility, this ex-vivo study was initiated.

Methods

Test circuits (primed with human whole blood) were set up in accordance with the recommendations of international standards for in-vitro evaluation of new components and systems of ECC. Diagonal pumps were either set up with non-pulsatile (n = 5, NPG) or pulsatile (n = 5, PG) pump settings and evaluated for 6 h. All analyses were conducted with human whole blood. Blood samples were repeatedly drawn from the test circuits and analyzed regarding free hemoglobin, interleukin 8 (IL-8), platelet aggregation and acquired von Willebrand syndrome (AVWS).

Results

After 1 h of circulation, a significant coagulation impairment (impaired platelet function and AVWS) was observed in both groups. After 6 h of circulation, increased IL-8 concentrations were measured in both groups (NPG: 0.05 ± 0.03 pg./mL, PG: 0.03 ± 0.01 pg./mL, p = 0.48). Pulsatile pump flow resulted in significantly increased hemolysis after 6 h of circulation (NPG: 37.3 ± 12.4 mg/100 L; PG: 59.6 ± 14.5 mg/100 L; p < 0.05).

Conclusion

Our results indicate that the coagulative impairment takes place in the early phase of ECC. Pulsatility did not affect the occurrence of AVWS ex-vivo. Prolonged durations of pulsatile pump flow led to increased hemolysis and therefore, its prolonged use should be employed cautiously in clinical practice with appropriate monitoring.

Outcome of Out-of-Hospital Cardiac Arrest Patients Stratified by Pre-Clinical Loading with Aspirin and Heparin: A Retrospective Cohort Analysis

Background: Out-of-hospital cardiac arrest (OHCA) has a high prevalence of obstructive coronary artery disease and total coronary occlusion. Consequently, these patients are frequently loaded with antiplatelets and anticoagulants before hospital arrival. However, OHCA patients have multiple non-cardiac causes and high susceptibility for bleeding. In brief, there is a gap in the evidence for loading in OHCA patients. Objective: The current analysis stratified the outcome of patients with OHCA according to pre-clinical loading. Material and Methods: In a retrospective analysis of an all-comer OHCA registry, patients were stratified by loading with aspirin (ASA) and unfractionated heparin (UFH). Bleeding rate, survival to hospital discharge and favorable neurological outcomes were measured. Results: Overall, 272 patients were included, of whom 142 were loaded. Acute coronary syndrome was diagnosed in 103 patients. One-third of STEMIs were not loaded. Conversely, 54% with OHCA from non-ischemic causes were pretreated. Loading was associated with increased survival to hospital discharge (56.3 vs. 40.3%, p = 0.008) and a more favorable neurological outcome (80.7 vs. 62.6% p = 0.003). Prevalence of bleeding was comparable (26.8 vs. 31.5%, p = 0.740). Conclusions: Pre-clinical loading did not increase bleeding rates and was associated with favorable survival. Overtreatment of OHCA with non-ischemic origin, but also undertreatment of STEMI-OHCA were documented. Loading without definite diagnosis of sustained ischemia is debatable in the absence of reliable randomized controlled data.

Serum proteome alterations during conventional and extracorporeal resuscitation in pigs

Background

Only a small number of patients survive an out-of-hospital cardiac arrest (CA) and can be discharged from hospital alive with a large percentage of these patients retaining neurological impairments. In recent years, extracorporeal cardiopulmonary resuscitation (ECPR) has emerged as a beneficial strategy to optimize cardiac arrest treatment. However, ECPR is still associated with various complications. To reduce these problems, a profound understanding of the underlying mechanisms is required. This study aims to investigate the effects of CA, conventional cardiopulmonary resuscitation (CPR) and ECPR using a whole-body reperfusion protocol (controlled and automated reperfusion of the whole body—CARL) on the serum proteome profiles in a pig model of refractory CA.

Methods

N = 7 pigs underwent 5 min of untreated CA followed by 30 min CPR and 120 min perfusion with CARL. Blood samples for proteomic analysis were drawn at baseline, after CPR and at the end of the CARL period. Following albumin-depletion, proteomic analysis was performed using liquid chromatography–tandem mass spectrometry.

Results

N = 21 serum samples were measured resulting in the identification and quantification of 308–360 proteins per sample and 388 unique proteins in total. The three serum proteome profiles at the investigated time points clustered individually and segregated almost completely when considering a 90% confidence interval. Differential expression analysis showed significant abundance changes in 27 proteins between baseline and after CPR and in 9 proteins after CARL compared to CPR. Significant findings were further validated through a co-abundance cluster analysis corroborating the observed abundance changes.

Conclusions

The presented data highlight the impact of systemic ischemia and reperfusion on the entire serum proteome during resuscitation with a special focus on changes regarding haemolysis, coagulation, inflammation, and cell-death processes. Generally, the observed changes contribute to post-ischemic complications. Better understanding of the underlying mechanisms during CA and resuscitation may help to limit these complications and improve therapeutic options.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03441-4.

The association of modifiable mechanical ventilation settings, blood gas changes and survival on extracorporeal membrane oxygenation for cardiac arrest

RESEARCH QUESTION

Given the relative independence of ventilator settings from gas exchange and plasticity of blood gas values during extracorporeal cardiopulmonary resuscitation (ECPR), do mechanical ventilation parameters and blood gas values influence survival?

METHODS

Observational cohort study of 7488 adult patients with ECPR from the Extracorporeal Life Support Organization (ELSO) Registry. We performed case-mix adjustment for severity of illness and patient type using generalized estimating equation logistic regression to determine factors associated with hospital survival accounting for clustering by center, standardizing variables by 1 standard deviation (SD) of their values. We examined non-linear relationships between ventilatory and blood gas values with hospital survival.

RESULTS

Hospital survival was decreased with higher PaO2 on ECMO (OR 0.69, per 1SD increase [95% CI 0.64, 0.74]; p < 0.001) and with any relative changes in PaCO2 (pre-arrest to on-ECMO) in a non-linear fashion. Survival was worsened with any peak inspiratory pressure >20 cmH20 (OR 0.69, per 1SD [0.64, 0.75]; p < 0.001) and above 40% fraction of inspired oxygen (OR 0.75, per 1SD [0.69, 0.82]; p < 0.001), and with higher dynamic driving pressure (OR 0.72, per 1 SD increase [0.65, 0.79]; <0.001). Ventilation settings and blood gas values varied widely across hospitals, but were not associated with annual hospital ECPR case volume.

CONCLUSION

Lower ventilatory pressures, avoidance of hyperoxia, and relatively unchanged CO2 (pre- to on-ECMO) were all associated with survival in patients after ECPR, yet varied across hospitals. Our findings represent potential targets for prospective trials for this rapidly growing therapy to test if these associations have causality.

Resuscitation Using ECPR During In-Hospital Cardiac Arrest (RESCUE-IHCA) Mortality Prediction Score and External Validation

OBJECTIVES

The aim of this study was to develop and validate a score to accurately predict the probability of death for adult extracorporeal cardiopulmonary resuscitation (ECPR).

BACKGROUND

ECPR is being increasingly used to treat refractory in-hospital cardiac arrest (IHCA), but survival varies from 20% to 40%.

METHODS

Adult patients with extracorporeal membrane oxygenation for IHCA (ECPR) were identified from the American Heart Association GWTG-R (Get With the Guidelines-Resuscitation) registry. A multivariate survival prediction model and score were developed to predict hospital death. Findings were externally validated in a separate cohort of patients from the Extracorporeal Life Support Organization registry who underwent ECPR for IHCA.

RESULTS

A total of 1,075 patients treated with ECPR were included. Twenty-eight percent survived to discharge in both the derivation and validation cohorts. A total of 6 variables were associated with in-hospital death: age, time of day, initial rhythm, history of renal insufficiency, patient type (cardiac vs noncardiac and medical vs surgical), and duration of the cardiac arrest event, which were combined into the RESCUE-IHCA (Resuscitation Using ECPR During IHCA) score. The model had good discrimination (area under the curve: 0.719; 95% CI: 0.680-0.757) and acceptable calibration (Hosmer and Lemeshow goodness of fit P = 0.079). Discrimination was fair in the external validation cohort (area under the curve: 0.676; 95% CI: 0.606-0.746) with good calibration (P = 0.66), demonstrating the model's ability to predict in-hospital death across a wide range of probabilities.

CONCLUSIONS

The RESCUE-IHCA score can be used by clinicians in real time to predict in-hospital death among patients with IHCA who are treated with ECPR.

How effective is extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest? A systematic review and meta-analysis

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) has gained increasing as a promising but resource-intensive intervention for out-of-hospital cardiac arrest (OHCA). There is little data to quantify the impact of this intervention and the patients likely to benefit from its use. We conducted a meta-analysis of the literature to assess the survival benefit associated with ECPR for OHCA.

METHODS

We searched PubMed, Embase, and Scopus databases to identify relevant observational studies and randomized control trials. We used the Newcastle-Ottawa Scale and Cochrane risk-of-bias tool to assess studies' quality. We performed random-effects meta-analysis for the primary outcome of survival to hospital discharge and used meta-regressions to assess heterogeneity.

RESULTS

We identified 1287 articles, reviewed the full text of 209 and included 44 in our meta-analysis. Our analysis included 3097 patients with OHCA. Patients' mean age was 52, 79% were male, and 60% had primary ventricular fibrillation/ventricular tachycardia arrest. We identified a survival-to-discharge rate of 24%; 18% survived with favorable neurologic function. 30- and 90-days survival rates were both around 18%. The majority of included articles were high quality studies.

CONCLUSIONS

Extracorporeal cardiopulmonary resuscitation is a promising but resource-intensive intervention that may increase rates of survival to hospital discharge among patients who experience OHCA.

Outcomes after mechanical versus manual chest compressions in eCPR patients

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (eCPR) is an established treatment option for cardiac arrest. Mechanical reanimation devices are increasingly used but have been associated with complications. This study evaluates typical injury patterns and differences after mechanical versus manual chest compressions among patients undergoing eCPR.

METHODS

From 2016 to 2020, 108 eCPR patients were retrospectively analyzed. Primary endpoints were traumatic, hemorrhagic, or inner organ-related complications, defined as pneumothorax, pulmonary bleeding, major bleeding, gastrointestinal bleeding, gastrointestinal ischemia, cardiac tamponade, aortic dissection, sternal or rib fracture.

RESULTS

70 patients were treated with mechanical CPR (mCPR) and 38 with conventional CPR (cCPR). There were more CPR-related injuries in the mCPR group (55% vs. 83%, p = 0.01), CPR duration was longer (cCPR 40 ± 28 min vs. mCPR 69 ± 25 min, p = 0.01). There was no significant difference in mortality between the groups.

CONCLUSION

Mechanical CPR devices are associated with a higher incidence of traumatic and hemorrhagic injuries in patients undergoing eCPR.

Management of out-of hospital cardiac arrest patients with extracorporeal cardiopulmonary resuscitation in 2021

INTRODUCTION

Over the last decade, eCPR programs have become more and more popular, at least amongst high-volume centers. Despite its rise in popularity and promising outcome, strategies concerning pre- and post-implantation of VA-ECMO remain at least debatable. Besides, integrating the appropriate set-up, managing anticoagulation, implementing LV-venting, and predicting neurological outcome play important roles in caring for thise highly selective patient-collective. We sought to present our institutional´s techniques for establishing an eCPR program and managing patients peri- and post implantation in eCPR-runs.

AREAS COVERED

This manuscript covers the majority of clinical concerns and parameters for establishing an eCPR program and its recent advantages. We will describe a safe way of cannulation, setting anticoagulation goals, strategies for LV-venting and ICU-treatment. Also included, an elaboration on neurological and cardiac prognostication.

EXPERT OPINION

We advocate ultrasound-guided cannula placement in eCPR patients. Also, we emphasize the importance of using stiffer wires and smaller arterial cannula sizes due to the different physiological parameters of OHCA patients. After cannulation, we aim for lower flow goals, the concept of 'partial VA-ECMO,' and lower anticoagulatory targets. LV-venting with Impella should remain an individual case to case decision.