Clinical complications during veno-arterial extracorporeal membrane oxigenation in post-cardiotomy and non post-cardiotomy shock: still the achille's heel

Extracorporeal membrane oxygenation for adults with respiratory failure secondary to cardiorespiratory disease: evolving indications and clinical practice

Extracorporeal membrane oxygenation (ECMO) can support patients with severe cardiorespiratory failure presenting with hypoxia who would otherwise have not survived. Patient selection for ECMO is challenging and relies on the integration of physiological variables with an assessment of reversibility of the underlying condition or suitability for transplantation. In this review, we focus on patients with cardiorespiratory disease who may present with severe hypoxia. We will discuss the indications and contraindications for ECMO; the evidence for ECMO, which is limited to a small number of clinical trials and registry data; the complications of ECMO; expanding technologies and indications; the development of a multidisciplinary ECMO network; and future research. The aim is to increase knowledge of this important area for respiratory physicians.

Pharmacokinetic Changes and Influencing Factors of Polymyxin B in Different ECMO Modes

Purpose

With the development of extracorporeal membrane oxygenation (ECMO) technology, the duration of ECMO support has gradually increased, leading to an increased risk of ECMO-related bacterial resistance. Polymyxin B (PMB) is used to treat drug-resistant bacterial infections. However, the pharmacokinetic (PK) parameters of antibiotics may change during ECMO, resulting in over- or under-exposure. This study aimed to clarify the changes in PK parameters and identify factors influencing PMB levels in patients receiving venovenous or venoarterial ECMO.

Patients and Methods

A prospective PK study was performed in 11 patients receiving ECMO with resistant bacteria. After reaching a steady state, the drug concentrations of PMB pre- and post-oxygenator were measured. Nonlinear mixed-effects modelling was used to construct a population PK model for PMB. Microbial results were assessed using repeated cultures at the end of treatment. Semiquantitative microbial culture results were used to form clearance and uncleared groups.

Results

The PMB concentrations were not significantly different between pre- and post-oxygenator. A two-compartment model best described the PK of PMB. ECMO flow rate was included as a covariate of clearance (CL). Continuous renal replacement therapy (CRRT) were included as covariates on the volume of the central compartment. The PK parameters central compartment, volume of the peripheral compartment, CL, and inter-compartmental clearance or flow rate(Q) were 20.41 L, 9.86 L, 3.75 L/h, and 3.82 L/h. 7 patients (63.64%) had two consecutive negative bacterial cultures at discharge. The Css,avg shows a significant difference between clearance group (2.26±0.72) and uncleared group (1.25±0.24), P<0.05.

Conclusion

There were no significant differences in PMB concentrations between pre- and post-oxygenator. The PK of PMB may be altered in patients receiving CRRT-ECMO. The ECMO flow rate is strongly correlated with the CL. The Css,avg is correlated with the bacterial clearance rate. In clinical practice, increasing the incidence of therapeutic drug monitoring may improve the clinical outcomes.

Enhancing lung transplantation with ECMO: a comprehensive review of mechanisms, outcomes, and future considerations

BACKGROUND

Lung transplantation (LTx) is a critical intervention for patients with end-stage lung disease. However, challenges such as donor organ scarcity and post-transplant complications significantly affect its success. Recent advancements in Extracorporeal Membrane Oxygenation (ECMO) have shown promise in improving the outcomes and expanding eligibility for LTx.

METHODS

A comprehensive literature review was conducted, focusing on studies that explore the use of ECMO in lung transplantation. A thorough search of relevant studies on ECMO and LTx was conducted using multiple scholarly databases and relevant keywords, resulting in 73 studies that met the inclusion criteria. Sources included peer-reviewed journals and clinical trial results, with emphasis on articles captured recent advancements in ECMO technology and techniques.

RESULTS

ECMO has been crucial in supporting patients before, during, and after LTx. It serves as a bridge to transplantation by maintaining pulmonary and circulatory stability in critically ill patients awaiting donor organs. ECMO also aids in the evaluation of marginal donor lungs and supports patients through acute post-transplant complications. Recent technological advancements have improved the safety and efficacy of ECMO, further solidifying its role in LTx.

CONCLUSION

In conclusion, this review underscores ECMO's critical role in enhancing outcomes across all stages of lung transplantation. Its various configurations and strategies have shown promise in stabilizing critically ill patients and improving transplant success rates. Looking ahead, it's important to gather more information about the long-term outcomes and potential complications associated with ECMO use. More research and data collection will help us understand the benefits and risks better, leading to improved decision-making and patient care in this field.

Extracorporeal Membrane Oxygenation as Life Support in Neonatal Respiratory Failure: A Single-Center Cohort Study and a Systematic Review

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a life support in newborns with severe respiratory failure. Our main objective was to evaluate the mortality of patients and define positive and negative predictive factors of survival.

METHODS

We performed a Strengthening the Reporting of Observational Studies in Epidemiology (STROBE)-conformed retrospective observational study and a systematic review, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Our data were analyzed using R (v.4.2.1). We performed survival analysis, correlation analysis, and Fisher's exact test. The first endpoint was the mortality rate. The second endpoint was to evaluate all factors associated with survival. The third endpoint was focused on complications of ECMO.

RESULTS

Our study included 8 patients treated in our centers and 45 patients from the literature review. Survival was 79%. Positive predictive factors of survival were a length of ECMO of less than 10 days and male neonates, while prematurity and the presence of 2 complications were negative predictive factors.

CONCLUSIONS

ECMO functions as life support, although mortality and morbidity risks are high.

Use of Intravascular Micro-Axial Left Ventricular Assist Devices as a Bridging Strategy for Cardiogenic Shock: Mid-Term Outcomes

Objectives: Patients in cardiogenic shock (CS) may be successfully bridged using intravascular micro-axial left ventricular assist devices (M-LVADs) for recovery or determination of definitive therapy. Methods: One hundred and seven CS patients implanted with M-LVADs from January 2020 to May 2024 were divided into four groups; group-1: 34 patients (transplant); group-2: 25 patients (LVAD); group-3: 42 patients (postcardiotomy CS (PCCS)); group-4: 6 patients (decision/recovery but excluded from analysis). Multivariable logistic regression and Multivariable Coxregression models identified predictors of early -hospital and late mortality, and Odds ratios (ORs) and hazard ratios (HRs) with p < 0.05, respectively, were considered statistically significant. SPSS 29.0 and Python 3.11.1. were used for analyses. Results: Complications included device-malfunction (6%), gastrointestinal bleed (9%), long-term hemodialysis (21%), axillary hematoma requiring re-exploration (10%), heparin-induced thrombocytopenia (4%) requiring heparin therapy cessation/initiation of argatroban infusion, and non-fatal stroke (11%). Early hospital mortality included 13 patients: 2 in group-1, 1 in group-2, 10 in group-3 (p = 0.02). In the Logistic-Regression model, category of CS requiring an M-LVAD was significant (OR = 4.7, p = 0.05). Patients were followed for 4.5 years (mean follow-up was 23 ± 17 months), and 23 deaths occurred; group-1: 3 patients, group-2: 5 patients, and group-3: 15 patients (p = 0.019). At 4.5 years, actuarial survival was 90.7 ± 5.1% in group-1, 79.2 ± 8.3% in group-2, 62.8 ± 7.7% in group-3 (p = 0.01). In the Cox-Regression model, M-LVAD category (HR = 3.63, p = 0.04), and long-term postoperative dialysis (HR = 3.9, p = 0.002) emerged as predictors of long-term mortality. Conclusions: In cardiogenic shock, mid-term outcomes demonstrate good survival with M-LVADs as bridge to transplant/durable LVADs and reasonable survival with M-LVADs as a bridge to recovery following cardiotomy, accompanied by reduced ECMO usage, and early ambulation/rehabilitation.

Extracorporeal Membrane Oxygenation-Supported Patient Outcome Undergoing Transcatheter Aortic Valve Replacement

The efficacy and safety of extracorporeal membrane oxygenation (ECMO) support during transcatheter aortic valve replacement (TAVR) remains unknown. We conducted a meta-analysis to compare benefit and risk of ECMO in TAVR patients. Bibliographic databases were searched from inception to January 1, 2024. Included studies involved patients ≥18 years old undergoing TAVR and using ECMO emergently or prophylactically. Mortality and procedure success were primary outcomes. Peri- or postoperative complications were the secondary outcomes. We identified 11 observational studies, including 2,275 participants (415 ECMO and 1,860 non-ECMO). The unadjusted mortality risk in ECMO-supported patient was higher than non-ECMO patients (odds ratio [OR] 1.73). The mortality unadjusted risk remained high (OR 3.89) and statistically significant for prophylactic ECMO. Prophylactic ECMO had lower mortality risk compared with emergent ECMO (OR 0.17). Extracorporeal membrane oxygenation-supported patients had lower procedural success rate (OR 0.10). Extracorporeal membrane oxygenation patients undergoing TAVR had significantly increased risk of bleeding (OR 3.32), renal failure (OR 2.38), postoperative myocardial infarction (OR 1.89), and stroke (OR 2.32) compared with non-ECMO patients. Clinical results are not improved by ECMO support in patients with high-risk TAVR. Prophylactic ECMO outperforms emergent. Overall, ECMO support increases mortality and postoperative complications. Transcatheter aortic valve replacement outcomes may improve with prophylactic ECMO in high-risk situations.

Investigations of Differential Hypoxemia During Venoarterial Membrane Oxygenation with and Without Impella Support

PURPOSE

Venoarterial extracorporeal membrane oxygenation (VA ECMO) is used in patients with refractory cardiac or cardio-pulmonary failure. Native ventricular output interacts with VA ECMO flow and may hinder sufficient oxygenation to the heart and the brain. Further on, VA ECMO leads to afterload increase requiring ventricular unloading. The aim of the study was to investigate aortic blood flow and oxygenation for various ECMO settings and cannula positions with a numerical model.

METHODS

Four different aortic cannula tip positions (ascending aorta, descending aorta, abdominal aorta, and iliac artery) were included in a model of a human aorta. Three degrees of cardiac dysfunction and VA ECMO support (50%, 75% and 90%) with a total blood flow of 6 l/min were investigated. Additionally, the Impella CP device was implemented under 50% support condition. Blood oxygen saturation at the aortic branches and the pressure acting on the aortic valve were calculated.

RESULTS

A more proximal tip orientation is necessary to increase oxygen supply to the supra-aortic and coronary arteries for 50% and 75% support. During the 90% support scenario, proper oxygenation can be achieved independently of tip position. The use of Impella reduces afterload by 8-17 mmHg and vessel oxygenation is similar to 50% VA ECMO support. Pressure load on the aortic valve increases with more proximal tip position and is decreased during Impella use.

CONCLUSIONS

We present a simulation model for the investigation of hemodynamics and blood oxygenation with various mechanical circulatory support systems. Our results underline the intricate and patient-specific relationship between extracorporeal support, cannula tip orientation and oxygenation capacity.

Cardiopulmonary bypass and VA-ECMO induced immune dysfunction: common features and differences, a narrative review

Cardiopulmonary bypass (CPB) and veno-arterial extracorporeal membrane oxygenation are critical tools in contemporary cardiac surgery and intensive care, respectively. While these techniques share similar components, their application contexts differ, leading to distinct immune dysfunctions which could explain the higher incidence of nosocomial infections among ECMO patients compared to those undergoing CPB. This review explores the immune modifications induced by these techniques, comparing their similarities and differences, and discussing potential treatments to restore immune function and prevent infections. The immune response to CPB and ECMO involves both humoral and cellular components. The kinin system, complement system, and coagulation cascade are rapidly activated upon blood contact with the circuit surfaces, leading to the release of pro-inflammatory mediators. Ischemia-reperfusion injury and the release of damage-associated molecular patterns further exacerbate the inflammatory response. Cellular responses involve platelets, neutrophils, monocytes, dendritic cells, B and T lymphocytes, and myeloid-derived suppressor cells, all of which undergo phenotypic and functional alterations, contributing to immunoparesis. Strategies to mitigate immune dysfunctions include reducing the inflammatory response during CPB/ECMO and enhancing immune functions. Approaches such as off-pump surgery, corticosteroids, complement inhibitors, leukocyte-depleting filters, and mechanical ventilation during CPB have shown varying degrees of success in clinical trials. Immunonutrition, particularly arginine supplementation, has also been explored with mixed results. These strategies aim to balance the inflammatory response and support immune function, potentially reducing infection rates and improving outcomes. In conclusion, both CPB and ECMO trigger significant immune alterations that increase susceptibility to nosocomial infections. Addressing these immune dysfunctions through targeted interventions is essential to improving patient outcomes in cardiac surgery and critical care settings. Future research should focus on refining these strategies and developing new approaches to better manage the immune response in patients undergoing CPB and ECMO.

Impact of Heart Failure Etiology on Waitlist Mortality in Heart Transplant Candidates Supported With Extracorporeal Membrane Oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has gained traction as a bridge to heart transplantation (HT) but remains associated with increased waitlist mortality. This study explores whether this risk is modified by underlying heart failure (HF) etiology.

METHODS

Using the Organ Procurement and Transplantation Network registry, we conducted a retrospective review of first-time adult HT candidates from 2018 through 2022. Patients were categorized as "ECMO", if ECMO was utilized during the waitlisting period, or "No ECMO" otherwise. Patients were then stratified according to the following HF etiology: ischemic cardiomyopathy (CMP), dilated nonischemic CMP, restrictive CMP, hypertrophic CMP, and congenital heart disease (CHD). After baseline comparisons, waitlist mortality was characterized for ECMO and HF etiology using the Fine-Gray regression.

RESULTS

A total of 16 143 patients were identified of whom 7.0% (n = 1063) were bridged with ECMO. Compared to No ECMO patients, ECMO patients had shorter waitlist durations (46.3 vs. 185.0 days, p < 0.01) and were more likely to undergo transplantation (75.3% vs. 70.3%, p < 0.01). Outcomes analysis revealed that ECMO was associated with increased mortality risk (subdistribution hazard ratio [SHR]: 3.42, p < 0.01), a risk that persisted in all subgroups and was notably high in CHD (SHR: 4.83, p < 0.01) and hypertrophic CMP (SHR: 9.78, p < 0.01). HF etiology comparison within ECMO patients revealed increased mortality risk with CHD (SHR: 3.22, p < 0.01). Within No ECMO patients, hypertrophic CMP patients had lower mortality risk (SHR: 0.64, p = 0.03).

CONCLUSIONS

The increased waitlist mortality risk with ECMO persisted after stratification by HF etiology. These findings can help decision-making surrounding candidacy for cannulation and prognostic evaluation.

In Patients with Cardiogenic Shock, Extracorporeal Membrane Oxygenation Is Associated with Very High All-Cause Inpatient Mortality Rate

Background: The goal of this study was to evaluate the effect of extracorporeal membrane oxygenation (ECMO) on mortality in patients with cardiogenic shock excluding Impella and IABP use. Method: The large Nationwide Inpatient Sample (NIS) database was utilized to study any association between the use of ECMO in adults over the age of 18 and mortality and complications with a diagnosis of cardiogenic shocks. Results: ICD-10 codes for ECMO and cardiogenic shock for the available years 2016-2020 were utilized. A total of 796,585 (age 66.5 ± 14.4) patients had a diagnosis of cardiogenic shock excluding Impella. Of these patients, 13,160 (age 53.7 ± 15.4) were treated with ECMO without IABP use. Total inpatient mortality without any device was 32.7%. It was 47.9% with ECMO. In a multivariate analysis adjusting for 47 variables such as age, gender, race, lactic acidosis, three-vessel intervention, left main myocardial infarction, cardiomyopathy, systolic heart failure, acute ST-elevation myocardial infarction, peripheral vascular disease, chronic renal disease, etc., ECMO utilization remained highly associated with mortality (OR: 1.78, CI: 1.6-1.9, p < 0.001). Evaluating teaching hospitals only revealed similar findings. Major complications were also high in the ECMO cohort. Conclusions: In patients with cardiogenic shock, the use of ECMO was associated with the high in-hospital mortality regardless of comorbid condition, high-risk futures, or type of hospital.

Non-invasive assessment of left ventricular contractility by myocardial work index in veno-arterial membrane oxygenation patients: rationale and design of the MIX-ECMO multicentre observational study

Introduction and aims

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an increasingly utilized therapeutic choice in patients with cardiogenic shock, however, high complication rate often counteracts with its beneficial cardiopulmonary effects. The assessment of left ventricular (LV) function in key in the management of this population, however, the most commonly used measures of LV performance are substantially load-dependent. Non-invasive myocardial work is a novel LV functional measure which may overcome this limitation and estimate LV function independent of the significantly altered loading conditions of VA-ECMO therapy. The Usefulness of Myocardial Work IndeX in ExtraCorporeal Membrane Oxygenation Patients (MIX-ECMO) study aims to examine the prognostic role of non-invasive myocardial work in VA-ECMO-supported patients.

Methods

The MIX-ECMO is a multicentric, prospective, observational study. We aim to enroll 110 patients 48-72 h after the initiation of VA-ECMO support. The patients will undergo a detailed echocardiographic examination and a central echocardiography core laboratory will quantify conventional LV functional measures and non-invasive myocardial work parameters. The primary endpoint will be failure to wean at 30 days as a composite of cardiovascular mortality, need for long-term mechanical circulatory support or heart transplantation at 30 days, and besides that other secondary objectives will also be investigated. Detailed clinical data will also be collected to compare LV functional measures to parameters with established prognostic role and also to the Survival After Veno-arterial-ECMO (SAVE) score.

Conclusions

The MIX-ECMO study will be the first to determine if non-invasive myocardial work has added prognostic value in patients receiving VA-ECMO support.

Incidence, risk factors and outcomes of nosocomial infection in adult patients supported by extracorporeal membrane oxygenation: a systematic review and meta-analysis

BACKGROUND

An increasing number of patients requires extracorporeal membrane oxygenation (ECMO) for life support. This supportive modality is associated with nosocomial infections (NIs). This systematic review and meta-analysis aim to assess the incidence and risk factors of NIs in adult.

METHODS

We searched PubMed, Scopus, Web of Science, and ProQuest databases up to 2022. The primary endpoint was incidence of NI. Secondary endpoints included time to infection, source of infection, ECMO duration, Intensive care and hospital length of stay (LOS), ECMO survival and overall survival. Incidence of NI was reported as pooled proportions and 95% confidence intervals (CIs), while dichotomous outcomes were presented as risk ratios (RR) as the effective index and 95% CIs using a random-effects model.

RESULTS

Among the 4,733 adult patients who received ECMO support in the 30 included studies, 1,249 ECMO-related NIs per 1000 ECMO-days was observed. The pooled incidence of NIs across 18 studies involving 3424 patients was 26% (95% CI 14-38%).Ventilator-associated pneumonia (VAP) and bloodstream infections (BSI) were the most common NI sources. Infected patients had lower ECMO survival and overall survival rates compared to non-infected patients, with risk ratio values of 0.84 (95% CI 0.74-0.96, P = 0.01) and 0.80 (95% CI 0.71-0.90, P < 0.001), respectively.

CONCLUSION

Results showed that 16% and 20% lower of ECMO survival and overall survival in patients with NI than patients without NI, respectively. However, NI increased the risk of in-hospital mortality by 37% in infected patients compared with non-infected patients. In addition, this study identified the significant positive correlation between ECMO duration and ECMO-related NI.

Predictors of mortality and transfusion requirements in venoarterial extracorporeal membrane oxygenation patients

OBJECTIVE

The aim of this study was to evaluate the prognostic impact of variables, including thrombocytopenia and the amount of platelet transfusion, for predicting survival in venoarterial extracorporeal membrane oxygenation (ECMO) recipients. Additionally, we aimed to identify the predictors of increased transfusion requirement during venoarterial ECMO support.

METHODS

All patients who received venoarterial ECMO between December 2008 and March 2020 were retrospectively analyzed. Univariate and multivariate Cox regressions were used to evaluate in-hospital mortality according to variables including thrombocytopenia and daily average of platelet concentrate transfusion. Stepwise multiple linear regression analysis was used to identify independent predictors for transfusion requirements.

RESULTS

Analysis of 218 patients demonstrated severe thrombocytopenia as an independent predictor of in-hospital mortality (hazard ratio = 2.840, 95% CI: 1.593-5.063, P < .001), along with age, pre-ECMO cardiac arrest, and pH. In contrast, the amount of platelet transfusion was not associated with in-hospital mortality. Multiple variables, including the type of indication for ECMO were associated with transfusion requirements.

CONCLUSION

Our findings identified severe thrombocytopenia as an independent prognostic factor of in-hospital mortality. However, daily average platelet transfusion was not associated with survival outcomes. Additionally, our study identified predictive variables of increased transfusion requirements.

Mechanical Support in High-Risk Pulmonary Embolism: Review Article

Acute pulmonary embolism (PE) may manifest with mild nonspecific symptoms or progress to a more severe hemodynamic collapse and sudden cardiac arrest. A substantial thrombotic burden can precipitate sudden right ventricular strain and failure. Traditionally, systemic thrombolytics have been employed in such scenarios; however, patients often present with contraindications, or these interventions may prove ineffective. Outcomes for this medically complex patient population are unfavorable, necessitating a compelling argument for advanced therapeutic modalities or alternative approaches. Moreover, patients frequently experience complications beyond hemodynamic instability, such as profound hypoxia and multiorgan failure, necessitating assertive early interventions to avert catastrophic consequences. The existing data on the utilization of mechanical circulatory support (MCS) devices are not exhaustive. Various options for percutaneous MCS devices exist, each possessing distinct advantages and disadvantages. There is an imminent imperative to develop a tailored approach for this high-risk patient cohort to enhance their overall outcomes.

Mechanical ventilation during extracorporeal membrane oxygenation support - New trends and continuing challenges

BACKGROUND

The impact of mechanical ventilation on the survival of patients supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO) due to severe acute respiratory distress syndrome (ARDS) remains still a focus of research.

METHODS

Recent guidelines, randomized trials, and registry data underscore the importance of lung-protective ventilation during respiratory and cardiac support on ECMO.

RESULTS

This approach includes decreasing mechanical power delivery by reducing tidal volume and driving pressure as much as possible, using low or very low respiratory rate, and a personalized approach to positive-end expiratory pressure (PEEP) setting. Notably, the use of ECMO in awake and spontaneously breathing patients is increasing, especially as a bridging strategy to lung transplantation. During respiratory support in V-V ECMO, native lung function is of highest importance and adjustments of blood flow on ECMO, or ventilator settings significantly impact the gas exchange. These interactions are more complex in veno-arterial (V-A) ECMO configuration and cardiac support. The fraction on delivered oxygen in the sweep gas and sweep gas flow rate, blood flow per minute, and oxygenator efficiency have an impact on gas exchange on device side. On the patient side, native cardiac output, native lung function, carbon dioxide production (VCO2), and oxygen consumption (VO2) play a role. Avoiding pulmonary oedema includes left ventricle (LV) distension monitoring and prevention, pulse pressure >10 mm Hg and aortic valve opening assessment, higher PEEP adjustment, use of vasodilators, ECMO flow adjustment according to the ejection fraction, moderate use of inotropes, diuretics, or venting strategies as indicated and according to local expertise and resources.

CONCLUSION

Understanding the physiological principles of gas exchange during cardiac support on femoro-femoral V-A ECMO configuration and the interactions with native gas exchange and haemodynamics are essential for the safe applications of these techniques in clinical practice. Proning during ECMO remains to be discussed until further data is available from prospective, randomized trials implementing individualized PEEP titration during proning.

Fulminant Myocarditis and Venoarterial Extracorporeal Membrane Oxygenation: A Systematic Review

This systematic review aimed to look at the effectiveness of venoarterial extracorporeal membrane oxygenation (VA-ECMO) therapy in treating fulminant myocarditis and evaluating the optimal length of time a patient should be placed on VA-ECMO. Fulminant myocarditis is a potentially life-threatening medical condition most commonly brought on by cardiogenic shock, which often progresses to severe circulatory compromise, requiring the patient to be placed on some form of mechanical circulatory assistance to maintain adequate tissue perfusion. Medical centers have multiple mechanical assistive devices available for treatment at their disposal, but our area of focus was placed on one system in particular: VA-ECMO therapy. Although the technology has been around for more than 30 years, there is limited information on how effective VA-ECMO is regarding the treatment of fulminant myocarditis. Due to the lack of data regarding the treatment administration of VA-ECMO for fulminant myocarditis, standard treatment duration guidelines do not exist, resulting in a wide variation of treatment administrations among medical centers. In regard to short-term outcomes, VA-ECMO has shown to be effective in treating fulminant myocarditis, with a one-year post-hospital survival rate ranging from 57.1% to 78% at discharge. For long-term health and survival, the studies that recorded long-term survival ranged from 65% to 94.1%. However, given the small number of studies that pursue this, more research is needed to prove the efficacy of VA-ECMO for the treatment of fulminant myocarditis.

Outcomes of ECMO support with polypropylene membrane during pandemic times: a retrospective cohort study

BACKGROUND

The SARS-CoV-2 pandemic resulted in shortages of supplies, which limited the use of extracorporeal membrane oxygenation (ECMO) support. As a contingency strategy, polypropylene (PP) oxygenation membranes were used. This study describes the clinical outcomes in patients on ECMO with PP compared to poly-methylpentene (PMP) oxygenation membranes.

METHODS

Retrospective cohort of patients in ECMO support admitted between 2020 and 2021.

RESULTS

A total of 152 patients with ECMO support were included, 71.05% were men with an average age of 42 (SD 9.91) years. Veno-venous configuration was performed in 75.6% of cases. The PP oxygenation membranes required more changes 22 (63.1%), than the PMP Sorin® 24 (32,8%) and Euroset® 15 (31,9%) (p.0.022). The main indication for membrane change was low oxygen transfer for PP at 56.2%, Sorin® at 50%, and Euroset® at 14.8%. Renal replacement therapy was the most frequent complication with PP membrane in 22 patients (68.7%) Sorin® 25 patients (34.2%), and Euroset® 15 patients (31.9%) (p 0.001) without statistically significant differences in mortality.

CONCLUSION

PP oxygenation membranes was a useful and feasible strategy. It allowed a greater disponibility of ECMO support for critically ill in a situation of great adversity during the SARS-CoV-2 pandemic.

Optimizing Outcomes in Extracorporeal Membrane Oxygenation Postcardiotomy in Pediatric Population

Extracorporeal membrane oxygenation (ECMO) is a rapidly emerging advanced life support technique used in cardiorespiratory failure refractory to other treatments. There has been an influx in the number of studies relating to ECMO in recent years, as the technique becomes more popular. However, there are still significant gaps in the literature including complications and their impacts and methods to predict their development. This review evaluates the available literature on the complications of ECMO postcardiotomy in the pediatric population. Areas explored include renal, cardiovascular, hematological, infection, neurological, and hepatic complications. Incidence, risk factors and potential predictors, and scoring systems for the development of these complications have been evaluated.

Contemporary management of ventricular arrhythmias in heart failure

Enhanced ventricular arrhythmogenesis is commonly experienced by patients in the end-stage of heart failure spectrum. A high burden of ventricular arrhythmias can affect the ventricular systolic function, lead to unexpected hospitalizations and further deteriorate the prognosis. Management of ventricular arrhythmias in this population is challenging. Implantable cardioverter-defibrillators are protective for the immediate termination of life-threatening arrhythmias but they have no impact in reducing the arrhythmic burden. Combination treatment with invasive (catheter ablation, mechanical hemodynamic support, sympathetic denervation) and noninvasive (antiarrhythmic drugs, medical therapy for heart failure, programming of implantable devices) therapies is commonly required. The aim of this review is to present the available therapeutic options, with main focus on recently published data for catheter ablation and provide a stepwise treatment approach.

Pulmonary Artery Dual-Lumen Cannulation Versus Two Cannula Percutaneous Extracorporeal Membrane Oxygenation Configuration in Right Ventricular Failure

Refractory right ventricular failure has significant morbidity and mortality. Extracorporeal membrane oxygenation is indicated when medical interventions are deemed ineffective. However, it is still being determined if one configuration is better. We conducted a retrospective analysis of our institutional experience comparing the peripheral veno-pulmonary artery (V-PA) configuration versus the dual-lumen cannula with the tip in the pulmonary artery (C-PA). The analysis of a cohort of 24 patients (12 patients in each group). There was no difference in survival after hospital discharge (58.3% in the C-PA group compared to 41.7% in the V-PA group, p = 0.4). Among the C-PA group, there was a statistically significant shorter ICU length of stay (23.5 days [interquartile range {IQR} = 19-38.5] vs. 43 days [IQR = 30-50], p = 0.043) and duration of mechanical ventilation (7.5 days [IQR = 4.5-9.5] compared to (16.5 days [IQR = 9.5-22.5], p = 0.006) in the V-PA group. In the C-PA group, there were lower incidents of bleeding (33.33% vs. 83.33%, p =0.036) and combined ischemic events (0 vs. 41.67%, p = 0.037). In our single-center experience, the C-PA configuration might have a better outcome than the V-PA one. Further studies are needed to confirm our findings.

Oxygenated right ventricular assist device as part of veno-venopulmonary extracorporeal membrane oxygenation to support the right ventricle and pulmonary vasculature

COVID-19 infection can lead to severe acute respiratory distress syndrome (ARDS), right ventricular (RV) failure and pulmonary hypertension. Venovenous extracorporeal membrane oxygenation (V-V ECMO) has been used for patients with refractory hypoxemia. More recently dual-lumen right atrium to pulmonary artery oxygenated right ventricular assist devices (Oxy-RVAD) have been utilized in the severe medical refractory COVID ARDS setting. Historically, animal data has demonstrated that high continuous non-pulsatile RVAD flows, leading to unregulated and unprotected circulation through the pulmonary vessels is associated with an increased risk of pulmonary hemorrhage and increased amount of extravascular lung water. These risks are heightened in the setting of ARDS with fragile capillaries, left ventricular (LV) diastolic failure, COVID cardiomyopathy, and anticoagulation. Concurrently, due to infection, tachycardia, and refractory hypoxemia, high V-V ECMO flows to match high cardiac output are often necessary to maintain systemic oxygenation. Increase in cardiac output without a concurrent increase in VV ECMO flow will result in a higher fraction of deoxygenated blood returning to the right heart and therefore resulting in hypoxemia. Several groups have suggested using a RVAD only strategy in COVID ARDS; however, this exposes the patients to the risk of pulmonary hemorrhage. We present one of the first known cases using an RV mechanical support, partial flow pulmonary circulation, oxygenated Veno-venopulmonary (V-VP) strategy resulting in RV recovery, total renal recovery, awake rehabilitation, and recovery.

Starting and Sustaining an Extracorporeal Membrane Oxygenation Program

The use of extracorporeal membrane oxygenation (ECMO) is growing rapidly in all patient populations, especially adults for both acute lung or heart failure. ECMO is a complex, high risk, resource-intense, expensive modality that requires appropriate planning, training, and management for successful outcomes. This article provides an optimal approach and the basic framework for initiating a new ECMO program, which can be tailored to meet local needs. Setting up a new ECMO program and sustaining it requires institutional commitment, physician champions, multidisciplinary team involvement, ongoing training, and education of the ECMO team personnel and a robust quality assurance program to minimize complications and improve outcomes.

In Vivo Suction Pressures of Venous Cannulas During Veno-venous Extracorporeal Membrane Oxygenation

Extracorporeal lung support includes the risk of hemolysis due to suction pressures. Manufacturers measure the negative suction pressure across drainage cannulas for their products in vitro using water. Clinical experience suggests that hemolysis occurs in vivo already at much lower flow rates. The aim of this study was to analyze the in vivo suction pressure for veno-venous extracorporeal membrane oxygenation (VV-ECMO) cannulas. Prospective, observational study at a tertiary-care intensive care unit: 15 patients on VV-ECMO for severe ARDS were prospectively included. In vitro , the 25 Fr drainage cannula pressure drops below a critical level of around -100 mm Hg at a flow rate of 7.9 L/min, the 23 Fr drainage cannula at 6.6 L/min. In the clinical setting, critical suction pressures were reached at much lower flow rates (5.5 and 4.7 L/min; p < 0.0001, nonlinear regression). The in vitro data largely overestimate the safely achievable flow rates in daily clinical practice by 2.4 L/min (or 44%, 25 Fr) and 1.9 L/min (or 41%, 23 Fr). In vivo measurement of suction pressure of venous drainage cannulas differed significantly from in vitro derived measurements as the latter largely underestimate the resulting suction pressure.

Platelet Transfusion and In-Hospital Mortality in Veno-Arterial Extracorporeal Membrane Oxygenation Patients

Thrombocytopenia is common during extracorporeal membrane oxygenation (ECMO), and platelets are sometimes transfused to meet arbitrary goals. We performed a retrospective cohort study of veno-arterial (VA) ECMO patients from a single academic medical center and explored the relationship between platelet transfusion and in-hospital mortality using multivariable logistic regression. One hundred eighty-eight VA ECMO patients were included in the study. Ninety-one patients (48.4%) were transfused platelets during ECMO. Patients who received platelet transfusion had more coronary artery disease, lower platelet counts at cannulation, higher predicted mortality, lower nadir platelet counts, more ECMO days, and more red blood cell (RBC) and plasma transfusion. Mortality was 19.6% for patients who received no platelets, 40.8% for patients who received 1-3 platelets, and 78.6% for patients who received 4 or more platelets ( P &lt; 0.001). After controlling for confounding variables including baseline severity of illness, central cannulation, postcardiotomy status, RBC and plasma transfusion, major bleeding, and total ECMO days, transfusion of 4 or more platelets remained associated with in-hospital mortality; OR = 4.68 (95% CI = 1.18-27.28), P = 0.03. Our findings highlight the need for randomized controlled trials that compare different platelet transfusion triggers, so that providers can better understand when platelet transfusion is indicated in VA ECMO patients.

Increased Opportunities for Transplantation for Women in the New Heart Allocation System

BACKGROUND

Historically, women have had less access to advanced heart failure therapies, including temporary and permanent mechanical circulatory support and heart transplantation (HT), with worse waitlist and post-transplant survival compared with men. This study evaluated for improvement in sex differences across all phases of HT in the 2018 allocation system.

METHODS AND RESULTS

The United Network for Organ Sharing registry was queried to identify adult patients (≥18 years) listed for HT from October 18, 2016, to October 17, 2018 (old allocation), and from October 18, 2018, to October 18, 2020 (new allocation). The outcomes of interest included waitlist survival, pretransplant use of temporary and durable mechanical circulatory support, rates of HT, and post-transplant survival. There were 15,629 patients who were listed for HT and included in this analysis; 7745 (2039 women, 26.3%) in the new and 7875 patients (2074 women, 26.3%) in the old allocation system. When compared with men in the new allocation system, women were more likely to have lower priority United Network for Organ Sharing status at time of transplant, and less likely to be supported by an intra-aortic balloon pump (27.1% vs 32.2%, P < .001), with no difference in the use of venoarterial extracorporeal membrane oxygenation (5.5% vs 6.3%, P = .28). Despite these findings, when transplantation was viewed in the context of risk for death or delisting, the cumulative incidence of transplant within 6 months of listing was higher in women than men in the new allocation system (62.4% vs 54.9%, P < .001) with no differences in post-transplant survival. When comparing women in the old with the new allocation system, the distance traveled for organ procurement was 187.5 ± 207.0 miles vs 272.8 ± 233.7 miles (P < .001).

CONCLUSIONS

Although the use of temporary mechanical circulatory support in women remains lower than in men in the new allocation system, more women are being transplanted with comparable waitlist and post-transplant outcomes as men. Broader sharing may be making its greatest impact on improving transplant opportunities for women.

Comprehensive evaluation of Impella RP® in right ventricular failure

Right ventricular failure has a high morbidity and mortality in patients suffering from advanced heart failure, pulmonary hypertension, acute myocardial infarction after cardiac surgery and in left ventricular assist device patients. The Impella RP^® catheter is a mechanical circulatory device, positioned from a venous femoral percutaneous access and passing through the tricuspid and pulmonary valves, reaches the pulmonary artery. Impella RP (Abiomed Inc., MA, USA) acts as a direct right ventricle bypass and it provides a flow up to 4.4 liters per minute, unloading the right ventricle. The main contraindications are: thrombi in the vena cava, right atrium and ventricle and pulmonary artery; mechanical tricuspid or pulmonary prostheses. In this review, the principles of operations, clinical applications and results of Impella RP are summarized and evaluated.

Lung transplantation for acute respiratory distress syndrome: A multicenter experience

Acute respiratory distress syndrome (ARDS) is a rapidly progressive lung disease with a high mortality rate. Although lung transplantation (LTx) is a well-established treatment for a variety of chronic pulmonary diseases, LTx for acute lung failure (due to ARDS) remains controversial. We reviewed posttransplant outcome of ARDS patients from three high-volume European transplant centers. Demographics and clinical data were collected and analyzed. Viral infection was the main reason for ARDS (n = 7/13, 53.8%). All patients were admitted to ICU and required mechanical ventilation, 11/13 were supported with ECMO at the time of listing. They were granted a median LAS of 76 (IQR 50-85) and waited for a median of 3 days (IQR 1.5-14). Postoperatively, median length of mechanical ventilation was 33 days (IQR 17-52.5), median length of ICU and hospital stay were 39 days (IQR 19.5-58.5) and 54 days (IQR 43.5-127). Prolongation of peripheral postoperative ECMO was required in 7/13 (53.8%) patients with a median duration of 2 days (IQR 2-7). 30-day mortality was 7.7%, 1 and 5-year survival rates were calculated as 71.6% and 54.2%, respectively. Given the lack of alternative treatment options, the herein presented results support the concept of offering live-saving LTx to carefully selected ARDS patients.

Transcarotid Approach to Placement of an Impella 5.0

Microaxial left ventricular assist devices (mLVADs) have traditionally been placed through a transfemoral or transaxillary arterial approach. Transfemoral access is restrictive, significantly limiting postoperative patient ambulation. Transaxillary placement is preferred but not feasible in a subset of patients due to small arterial diameter or tight angulation of the thoracic outlet. Transcarotid delivery has been utilized for other cardiovascular device deployment with good success; however, this approach has not been described for mLVAD support. We present a case series of transcarotid placement of mLVADs in cases where a transaxillary and transfemoral approach was not feasible. From May 2017 to April 2019, six patients in cardiogenic shock required mLVAD support achieved via a transcarotid approach. Technical success was achieved in all patients. One patient was directly weaned from mLVAD support and two patients died on mLVAD support. Escalation to venoarterial extracorporeal membrane oxygenation (VA-ECMO) was required for three patients, two of whom subsequently died. There were no bleeding or valvular complications related to device placement, and no obvious or known neurologic complications related to mLVAD support. Transcarotid placement of mLVADs expands the utility of these devices as an alternative to traditional support strategies or prohibitive arterial anatomy; however, further study is needed to determine its efficacy.

HEROES V-V-HEmorRhagic cOmplications in Veno-Venous Extracorporeal life Support-Development and internal validation of multivariable prediction model in adult patients

BACKGROUND

During extracorporeal life support (ECLS), bleeding is one of the most frequent complications, associated with high morbidity and increased mortality, despite continuous improvements in devices and patient care. Risk factors for bleeding complications in veno-venous (V-V) ECLS applied for respiratory support have been poorly investigated. We aim to develop and internally validate a prediction model to calculate the risk for bleeding complications in adult patients receiving V-V ECLS support.

METHODS

Data from adult patients reported to the extracorporeal life support organization (ELSO) registry between the years 2010 and 2020 were analyzed. The primary outcome was bleeding complications recorded during V-V ECLS. Multivariable logistic regression with backward stepwise elimination was used to develop the predictive model. The performance of the model was tested by discriminative ability and calibration with receiver operating characteristic curves and visual inspection of the calibration plot.

RESULTS

In total, 18 658 adult patients were included, of which 3 933 (21.1%) developed bleeding complications. The prediction model showed a prediction of bleeding complications with an AUC of 0.63. Pre-ECLS arrest, surgical cannulation, lactate, pO₂ , HCO₃ , ventilation rate, mean airway pressure, pre-ECLS cardiopulmonary bypass or renal replacement therapy, pre-ECLS surgical interventions, and different types of diagnosis were included in the prediction model.

CONCLUSIONS

The model is based on the largest cohort of V-V ECLS patients and reveals the most favorable predictive value addressing bleeding events given the predictors that are feasible and when compared to the current literature. This model will help identify patients at risk of bleeding complications, and decision making in terms of anticoagulation and hemostatic management.

Utilization and outcomes of extracorporeal CO2 removal (ECCO2 R): Systematic review and meta-analysis of arterio-venous and veno-venous ECCO2 R approaches

INTRODUCTION

Extracorporeal carbon dioxide removal (ECCO₂ R) provides respiratory support to patients suffering from hypercapnic respiratory failure by utilizing an extracorporeal shunt and gas exchange membrane to remove CO₂ from either the venous (VV-ECCO₂ R) or arterial (AV-ECCO₂ R) system before return into the venous site. AV-ECCO₂ R relies on the patient's native cardiac function to generate pressures needed to deliver blood through the extracorporeal circuit. VV-ECCO₂ R utilizes a mechanical pump and can be used to treat patients with inadequate native cardiac function. We sought to evaluate the existing evidence comparing the subgroups of patients supported on VV and AV-ECCO₂ R devices.

METHODS

A literature search was performed to identify all relevant studies published between 2000 and 2019. Demographic information, medical indications, perioperative variables, and clinical outcomes were extracted for systematic review and meta-analysis.

RESULTS

Twenty-five studies including 826 patients were reviewed. 60% of patients (497/826) were supported on VV-ECCO₂ R. The most frequent indications were acute respiratory distress syndrome (ARDS) [69%, (95%CI: 53%-82%)] and chronic obstructive pulmonary disease (COPD) [49%, (95%CI: 37%-60%)]. ICU length of stay was significantly shorter in patients supported on VV-ECCO₂ R compared to AV-ECCO₂ R [15 (95%CI: 7-23) vs. 42 (95%CI: 17-67) days, p = 0.05]. In-hospital mortality was not significantly different [27% (95%CI: 18%-38%) vs. 36% (95%CI: 24%-51%), p = 0.26].

CONCLUSION

Both VV and AV-ECCO₂ R provided clinically meaningful CO₂ removal with comparable mortality.

Key Factors in Decision Making for ECLS: A Binational Factorial Survey

Background

Extracorporeal life support (ECLS) provides support to patients with cardiopulmonary failure refractory to conventional therapy. While ECLS is potentially life-saving, it is associated with severe complications; decision making to initiate ECLS must, therefore, carefully consider which patients ECLS potentially benefits despite its consequences.

Objective

To answer 2 questions: First, which medically relevant patient factors influence decisions to initiate ECLS? Second, what are factors relevant to decisions to withdraw a running ECLS treatment?

Methods

We conducted a factorial survey among 420 physicians from 111 hospitals in Switzerland and Germany. The study included 2 scenarios: 1 explored willingness to initiate ECLS, and 1 explored willingness to withdraw a running ECLS treatment. Each participant responded to 5 different vignettes for each scenario. Vignettes were analyzed using mixed-effects regression models with random intercepts.

Results

Factors in the vignettes such as patients’ age, treatment costs, therapeutic goal, comorbidities, and neurological outcome significantly influenced the decision to initiate ECLS. When it came to the decision to withdraw ECLS, patients’ age, days on ECLS, criteria for discontinuation, condition of the patient, comorbidities, and neurological outcome were significant factors. In both scenarios, patients’ age and neurological outcome were the most influential factors.

Conclusions

This study provided insights into physicians’ decision making processes about ECLS initiation and withdrawal. Patients’ age and neurological status were the strongest factors influencing decisions regarding initiation of ECLS as well as for ECLS withdrawal. The findings may contribute to a more refined understanding of complex decision making for ECLS.

Treatment of Cardiovascular Dysfunction With PDE5-Inhibitors - Temperature Dependent Effects on Transport and Metabolism of cAMP and cGMP

Introduction

Cardiovascular dysfunction is a potentially lethal complication of hypothermia. Due to a knowledge gap, pharmacological interventions are not recommended at core temperatures below 30°C. Yet, further cooling is induced in surgical procedures and survival of accidental hypothermia is reported after rewarming from below 15°C, advocating a need for evidence-based treatment guidelines. In vivo studies have proposed vasodilation and afterload reduction through arteriole smooth muscle cGMP-elevation as a favorable strategy to prevent cardiovascular dysfunction in hypothermia. Further development of treatment guidelines demand information about temperature-dependent changes in pharmacological effects of clinically relevant vasodilators.

Materials and Methods

Human phosphodiesterase-enzymes and inverted erythrocytes were utilized to evaluate how vasodilators sildenafil and vardenafil affected cellular efflux and enzymatic breakdown of cAMP and cGMP, at 37°C, 34°C, 32°C, 28°C, 24°C, and 20°C. The ability of both drugs to reach their cytosolic site of action was assessed at the same temperatures. IC₅₀- and K_i-values were calculated from dose–response curves at all temperatures, to evaluate temperature-dependent effects of both drugs.

Results

Both drugs were able to reach the intracellular space at all hypothermic temperatures, with no reduction compared to normothermia. Sildenafil IC₅₀ and K_i-values increased during hypothermia for enzymatic breakdown of both cAMP (IC₅₀: 122 ± 18.9 μM at 37°C vs. 269 ± 14.7 μM at 20°C, p < 0.05) and cGMP (IC₅₀: 0.009 ± 0.000 μM at 37°C vs. 0.024 ± 0.004 μM at 32°C, p < 0.05), while no significant changes were detected for vardenafil. Neither of the drugs showed significant hypothermia-induced changes in IC₅₀ and K_i–values for inhibition of cellular cAMP and cGMP efflux.

Conclusion

Sildenafil and particularly vardenafil were ableto inhibit elimination of cGMP down to 20°C. As the cellular effects of these drugs can cause afterload reduction, they show potential in treating cardiovascular dysfunction during hypothermia. As in normothermia, both drugs showed higher selectivity for inhibition of cGMP-elimination than cAMP-elimination at low core temperatures, indicating that risk for cardiotoxic side effects is not increased by hypothermia.

Venoarterial Extracorporeal Membrane Oxygenation for Postcardiotomy Shock-Analysis of the Extracorporeal Life Support Organization Registry

OBJECTIVES

Refractory postcardiotomy cardiogenic shock complicating cardiac surgery yields nearly 100% mortality when untreated. Use of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock has increased worldwide recently. The aim of the current analysis was to outline the trends in use, changing patient profiles, and in-hospital outcomes including complications in patients undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock.

DESIGN

Analysis of extracorporeal life support organization registry from January 2010 to December 2018.

SETTING

Multicenter worldwide registry.

PATIENTS

Seven-thousand one-hundred eighty-five patients supported with venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock.

INTERVENTIONS

Venoarterial extracorporeal membrane oxygenation.

MEASUREMENTS AND MAIN RESULTS

Hospital death, weaning from extracorporeal membrane oxygenation, hospital complications. Mortality predictors were assessed by multivariable logistic regression. Propensity score matching was performed for comparison of peripheral and central cannulation for extracorporeal membrane oxygenation. A significant trend toward more extracorporeal membrane oxygenation use in recent years (coefficient, 0.009; p < 0.001) was found. Mean age was 56.3 ± 14.9 years and significantly increased over time (coefficient, 0.513; p < 0.001). Most commonly, venoarterial extracorporeal membrane oxygenation was instituted after coronary artery bypass surgery (26.8%) and valvular surgery (25.6%), followed by heart transplantation (20.7%). Overall, successful extracorporeal membrane oxygenation weaning was possible in 4,520 cases (56.4%), and survival to hospital discharge was achieved in 41.7% of cases. In-hospital mortality rates remained constant over time (coefficient, -8.775; p = 0.682), whereas complication rates were significantly reduced (coefficient, -0.009; p = 0.003). Higher mortality was observed after coronary artery bypass surgery (65.4%), combined coronary artery bypass surgery with valve (68.4%), and aortic (69.6%) procedures than other indications. Lower mortality rates were observed in heart transplantation recipients (46.0%). Age (p < 0.001), central cannulation (p < 0.001), and occurrence of complications while on extracorporeal membrane oxygenation were independently associated with poorer prognosis.

CONCLUSIONS

The analysis confirmed increased use of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock. Mortality rates remained relatively constant over time despite a decrease in complications, in the setting of supporting older patients.

Analysis of the 2020 EACTS/ELSO/STS/AATS Expert Guidelines on the Management of Adult Postcardiotomy Extracorporeal Life Support

Extracorporeal life support (ECLS), also known as extracorporeal membrane oxygenation (ECMO), increasingly is used in postcardiotomy (PC) shock to facilitate a bridge to sustained recovery, long-term mechanical support, or heart transplantation. Given increasing prevalence and complexity of PC-ECLS, a joint expert consensus guideline was created in 2020 for management of adult PC-ECLS by the European Association for Cardio-Thoracic Surgery (EACTS), the Extracorporeal Life Support Organization (ELSO), the Society of Thoracic Surgeons (STS), and the American Association of Thoracic Surgery (AATS). The aim of this analysis was to comprehensively review the expert consensus guidelines, with particular emphasis on PC-ECLS candidacy, timing, cannula configuration, left ventricular distention, anticoagulation, ECLS weaning, and intensive care unit complications. This analysis finds the expert consensus guideline to be timely, pertinent, and clinically valuable, although there remains the need for larger clinical trials to codify best practices.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

Levosimendan for Treatment of Primary Graft Dysfunction After Heart Transplantation: Optimal Timing of Application

OBJECTIVES

Primary graft dysfunction remains a serious problem after heart transplant. Pharmacological treatment with the calcium sensitizer levosimendan may be an additive treatment for primary graft dysfunction.

MATERIALS AND METHODS

Patients undergoing heart transplant between 2010 and 2020 were retrospectively reviewed and divided depending on postoperative treatment with (n = 41) or without (n = 109) levosimendan. Recipients who received levosi mendan were further divided with regard to timing of levosimendan application (early group: started ≤48 hours posttransplant [n = 23]; late group: started >48 hours posttransplant [n = 18]).

RESULTS

Patients who received levosimendan treatment displayed a remarkable incidence (87.8%) of postoperative primary graft dysfunction with need for venoarterial extracorporeal membrane oxygenation and therefore often presented with perioperative morbidity. Patient with early application of levosimendan showed significantly decreased duration of venoarterial extracorporeal membrane oxygenation support (5.1 ± 3.5 days vs 12.6 ± 9.3 days in those with late application; P < .01) and decreased mortality during venoarterial extracorporeal membrane oxygenation support (0.0% vs 33.3% in early vs late group; P < .01). In addition, compared with patients with late levosimendan application, patients with early application needed fewer blood transfusions (P < .05), had shorter ventilation times (279 ± 235 vs 428 ± 293 h; P = .03), and showed a trend of reduced incidence of postoperative renal failure (69.6% vs 94.4%; P = .06). Moreover, survival analyses indicated an increased survival for patients with early start of levosimendan therapy within the first 48 hours after heart transplant (P = .09).

CONCLUSIONS

Pharmacotherapy with levosimendan may be a promising additive in the treatment of primary graft dysfunction after heart transplant. With administration of levosimendan within the first 48 hours posttransplant, rates of successful weaning from venoarterial extracorporeal membrane oxygenation and outcomes after heart transplant were shown to increase.

Microcirculatory Response to Changes in Venoarterial Extracorporeal Membrane Oxygenation Pump Flow: A Prospective Observational Study

Background: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) pump flow is crucial for maintaining organ perfusion in patients with cardiogenic shock, but VA-ECMO pump flow optimization remains as a clinical challenge. This study aimed to investigate the response of sublingual microcirculation to changes in VA-ECMO pump flow.

Methods: Sublingual microcirculation was measured before and after changing VA-ECMO pump flow according to the treatment plan of ECMO team within 24 h and at 24-48 h after VA-ECMO placement. In clinical events of increasing VA-ECMO pump flow, those events with increased perfused vessel density (PVD) were grouped into group A, and the others were grouped into group B. In clinical events of decreasing VA-ECMO pump flow, those events with increased PVD were grouped into group C, and the others were grouped into group D.

Results: Increased PVD was observed in 60% (95% CI, 38.5–81.5%) of the events with increasing VA-ECMO pump flow. The probability of increasing PVD after increasing VA-ECMO pump flow were higher in the events with a PVD < 15 mm/mm² at baseline than those with a PVD ≥ 15 mm/mm² [100% (95% CI, 54.1–100%) vs. 42.9% (95% CI, 17.7–71.1%), P = 0.042]. Other microcirculatory and hemodynamic parameters at baseline did not differ significantly between group A and B or between group C and D.

Conclusion: This study revealed contradictory and non-contradictory responses of sublingual microcirculation to changes in VA-ECMO pump flow. Tandem measurements of microcirculation before and after changing VA-ECMO pump flow may help to ensure a good microcirculation.

Veno-arterial extracorporeal membrane oxygenation: Special reference for use in 'post-cardiotomy cardiogenic shock' - A review with an Indian perspective

The ultimate goals of cardiovascular physiology are to ensure adequate end-organ perfusion to satisfy the local metabolic demand, to maintain homeostasis and achieve 'milieu intérieur'. Cardiogenic shock is a state of pump failure which results in tissue hypoperfusion and its associated complications. There are a wide variety of causes which lead to this deranged physiology, and one such important and common scenario is the post-cardiotomy state which is encountered in cardiac surgical units. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an important modality of managing post-cardiotomy cardiogenic shock with variable outcomes which would otherwise be universally fatal. VA-ECMO is considered as a double-edged sword with the advantages of luxurious perfusion while providing an avenue for the failing heart to recover, but with the problems of anticoagulation, inflammatory and adverse systemic effects. Optimal outcomes after VA-ECMO are heavily reliant on a multitude of factors and require a multi-disciplinary team to handle them. This article aims to provide an insight into the pathophysiology of VA-ECMO, cannulation techniques, commonly encountered problems, monitoring, weaning strategies and ethical considerations along with a literature review of current evidence-based practices.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management, and avoidance of complications, appraisal of new approaches and ethics, education, and training.

Tissue Factor Pathway Inhibitor Levels During Veno-Arterial Extracorporeal Membrane Oxygenation in Adults

Tissue factor pathway inhibitor (TFPI) has multiple anticoagulant properties. To our knowledge, no studies have measured TFPI levels in adult veno-arterial (VA) extracorporeal membrane oxygenation patients. We hypothesized that adult VA ECMO patients would have increased TFPI levels and slowed tissue factor triggered thrombin generation. Twenty VA ECMO patients had TFPI levels and thrombin generation lag time measured on ECMO day 1 or 2, day 3, and day 5. TFPI levels and thrombin generation lag time were compared against healthy control plasma samples. Mean TFPI levels were significantly higher in ECMO patients on ECMO day 1 or 2 = 81,877 ± 19,481 pg/mL, day 3 = 73,907 ± 26,690 pg/mL, and day 5 = 77,812 ± 23,484 pg/mL compared with control plasma = 38,958 ± 9,225 pg/mL (P < 0.001 for all comparisons). Median thrombin generation lag time was significantly longer in ECMO patients on ECMO day 1 or 2 = 10.0 minutes [7.5, 13.8], day 3 = 9.0 minutes [6.8, 12.1], and day 5 = 10.7 minutes [8.3, 15.2] compared with control plasma = 3.6 minutes [2.9, 4.2] (P < 0.001 for all comparisons). TFPI is increased in VA ECMO patients and tissue factor triggered thrombin generation is slowed. Increased TFPI levels could contribute to the multifactorial coagulopathy that occurs during ECMO.

Extracorporeal membrane oxygenation cannula-related chronic wound with a retained suture in a neonate

Extracorporeal membrane oxygenation (ECMO) is often employed to manage persistent pulmonary hypertension of the newborn where non-invasive therapies have failed. Delivery of ECMO requires insertion of indwelling catheters into central or peripheral vasculature; and this predisposes the recipient to development of catheter-associated skin infection; however, chronic non-healing wounds with granuloma formation are rare. We describe a case of an 8-month-old child who presented to our Plastic Surgery Services with a chronic left groin wound at ECMO cannula insertion site that failed medical management. The patient underwent wound exploration and debridement during which an old non-absorbable suture localized at the base of the wound was discovered. The foreign material as well as granuloma was removed, leading to the resolution of the chronic skin lesion and patient recovery without major complications. To our knowledge, this is the first case report describing an ECMO-associated paediatric chronic wound.

Right Atrial Perforation Leading to Cardiac Tamponade Following Veno-Venous Extracorporeal Membrane Oxygenation Cannulation

Extracorporeal membrane oxygenation (ECMO), as a supportive modality for cardiopulmonary failure, is increasing in its use due to improved advances in technology and experience lending to availability and ease of implementation. Complications with ECMO are quite common, and with increasing use, an increase in complications are a natural result. These complications can be from the underlying disease process or from the ECMO process itself, including cannula insertion. One such complication includes perforation of surrounding structures at site of insertion. We will present a case of right atrial perforation after single lumen cannula insertion, which led to development of cardiac tamponade and subsequently cardiac arrest. In addition to cannula design, lack of wire rigidity can play a role in wire migration and injury to surrounding structures. We emphasize the importance of ultrasound guidance and surveillance with echocardiogram or fluoroscopy during ECMO cannulation, regardless of cannula type, to prevent fatal complications. 

Right ventricular failure after left ventricular assist device implantation: a review of the literature

Right ventricular failure (RVF) following left ventricular assist device (LVAD) implantation remains a major complication which may significantly impair patient outcome. The genesis of RVF is, however, multifactorial, and the mechanisms underlying such a condition have not been fully elucidated, making its prevention challenging and the course not always predictable. Although preoperative risks factors can be associated with RV impairment, the physiologic changes after the LV support, can still hamper the function of the RV. Current medical treatment options are limited and sometimes, patients with a severe post-LVAD RVF may be unresponsive to pharmacological therapy and require more aggressive treatment, such as temporary RV support. We retrieved 11 publications which we assessed and divided in groups based on the RV support [extracorporeal membrane oxygenation (ECMO), right ventricular assist device (RVAD), TandemHeart with ProtekDuo cannula]. The current review comprehensively summarizes the main studies of the literature with particular attention to the RV physiology and its changes after the LVAD implantation, the predictors and prognostic score as well as the different modalities of temporary mechanical cardio-circulatory support, and its effects on patient prognosis for RVF in such a setting. In addition, it provides a decision making of the pre-, intra and post-operative management in high- and moderate- risk patients.

Acute Brain Injury in Postcardiotomy Shock Treated With Venoarterial Extracorporeal Membrane Oxygenation

OBJECTIVE

Acute brain injury (ABI) is common in venoarterial extracorporeal membrane oxygenation (VA-ECMO). One of the most common indications for use of VA-ECMO is postcardiotomy shock (PCS). The authors aimed to characterize the prevalence of ABI and its association with outcomes in this population.

DESIGN

prospective observational.

SETTING

Single-center tertiary care university hospital.

PARTICIPANTS

Fifty-two consecutive patients treated for PCS with VA-ECMO from November 2017 to March 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The median age of patients was 64 (interquartile range 44-84), 62% were male. Of 52 PCS patients treated with extracorporeal membrane oxygenation, 38% (n = 20) experienced acute brain injury. Ischemic stroke was the most common (n = 13, 25%). Patients with central versus peripheral cannulation experienced more ischemic and hemorrhagic strokes (8% v 38%, p = 0.04). Patients with intracardiac thrombus experienced more brain injury (n = 4, 8% p = 0.02). The in-hospital mortality in patients with brain injury was 90% (n = 18/20) compared to 78% (n = 25/32) in patients without brain injury.

CONCLUSIONS

ABI is common in postcardiotomy VA-ECMO and associated with worse outcome. Patients with central recanalization experienced the majority of acute strokes. Intracardiac thrombus was significantly associated with acute brain injury.

Platelet count reduction during in vitro membrane oxygenation affects platelet activation, neutrophil extracellular trap formation and clot stability, but does not prevent clotting

Introduction:

Due to improved technology and increased application the mortality during extracorporeal membrane oxygenation (ECMO) is constantly declining. Nevertheless, complications including haemorrhage or thrombus formation remain frequent. Local mitigation of coagulation within an ECMO system to prevent thrombus formation on ECMO components and optimizing systemic anticoagulation is an approach to reduce clotting and bleeding complications at once. Foreign surfaces of ECMO systems, activate platelets (PLTs), which besides their major role in coagulation, can trigger the formation of neutrophil extracellular traps (NETs) contributing to robust thrombus formation. The impact of a reduced PLT count on PLT activation and NET formation is of paramount importance and worth investigating.

Methods:

In this study platelet poor (PLT^–) and native (PLT⁺) heparinized human blood was circulated in two identical in vitro test circuits for ECMO devices for 6 hours. PLT reduction was achieved by a centrifugation protocol prior to the experiments. To achieve native coagulation characteristics within the test circuits, the initial heparin dose was antagonized by continuous protamine administration.

Results:

The PLT^– group showed significantly lower platelet activation, basal NET formation and limited clot stability measured via thromboelastometry. Fluorescent and scanning electron microscope imaging showed differences in clot composition. Both groups showed equal clot formation within the circuit.

Conclusions:

This study demonstrated that the reduction of PLTs within an ECMO system is associated with limited PLT activation and NET formation, which reduces clot stability but is not sufficient to inhibit clot formation per se.

Do-(Not-)Mechanical-Circulatory-Support Orders: Should We Ask All Cardiac Surgery Patients for Informed Consent for Post-Cardiotomy Extracorporeal Life Circulatory Support?

Post-cardiotomy extracorporeal life support (PC-ECLS) has seen a substantial increase in use over the past 10 years. PC-ECLS can be a life-saving procedure and is mostly applied in the presence of unexpected, severe cardio-respiratory complication. Despite PC-ECLS being critical in allowing for organ recovery, it is unfortunately closely connected with an unpredictable outcomes, high morbidity, and, even in the case of cardiac function improvement, potential sustained disabilities that have a life-changing impact for the patient and his or her family. Since the decision to start PC-ECLS is made in an acute setting, there is often only limited or no time for self-determined choices. Due to the major impact of the intervention, it would be highly desirable to obtain informed consent before starting PC-ECLS, since the autonomy of the patient and shared-decision making are two of the most important ethical values in modern medicine. Recent developments regarding awareness of the impacts of a prolonged intensive care stay make this a particularly relevant topic. Therefore, it would be desirable to develop a structural strategy that takes into account the likelihood of such an intervention and the wishes and preferences of the patient, and thus the related autonomy of the patient. This article proposes key points for such a strategy in the form of a PC-ECLS informed consent, a do-(not-)mechanical-circulatory-support order (D(N)MCS), and specific guidelines to determine the extent of the shared decision making. The concept presented in this article could be a starting point for improved and ethical PC-ECLS treatment and application.