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Introduction: An analysis on the ECLS use for patients with respiratory or cardiac support in COVID-19 based on an international response to EuroELSO survey, aims to generate a more comprehensive understanding of ECLS role during the recent viral pandemic. Methods: EuroELSO announced the survey at the 10th annual congress in London, May 2022. The survey covered 26 multiple-choice questions. Results: The survey returned 69 questionnaires from 62 centers across 22 European countries and seven centers across five non-European countries. Most of the centers providing ECLS for COVID-19 patients had more than 30 runs for respiratory support since December 2019. In the same period, at least 31 runs in adult COVID-19 patients have been performed in 48 of 69 centers (69.6%). The reported pediatric data from 18 centers is limited to less than the patients per center. Conclusion: Majority of the COVID-19 patients received respiratory ECLS support and adult patients dominated. The indications and contraindications are broadly aligned with available guidelines. Most of the centers considered age >65 or biological age as a relative or absolute contraindication for ECLS in COVID-19. ECLS withdrawal criteria in COVID-19 are controversial because the long-term outcomes after ECLS in COVID-19 and the impact of critical illness and the impact of long-COVID are still not known. [ABSTRACT FROM AUTHOR]

Timing and causes of hospital mortality in adult patients undergoing veno‐arterial extracorporeal membrane oxygenation (V‐A ECMO) have been poorly described. Aim of the current review was to investigate the timing and causes of death of adult patients supported with V‐A ECMO and subsequently define the "V‐A ECMO gap," which represents the patients who are successfully weaned of ECMO but eventually die during hospital stay. A systematic search was performed using electronic MEDLINE and EMBASE databases through PubMed. Studies reporting on adult V‐A ECMO patients from January 1993 to December 2020 were screened. The studies included in this review were studies that reported more than 10 adult, human patients, and no mechanical circulatory support other than V‐A ECMO. Information extracted from each study included mainly mortality and causes of death on ECMO and after weaning. Complications and discharge rates were also extracted. Sixty studies with 9181 patients were included for analysis in this systematic review. Overall mortality was 38.0% (95% confidence intervals [CIs] 34.2%‐41.9%) during V‐A ECMO support (reported by 60 studies) and 15.3% (95% CI 11.1%‐19.5%, reported by 57 studies) after weaning. Finally, 44.0% of patients (95% CI 39.8‐52.2) were discharged from hospital (reported by 60 studies). Most common causes of death on ECMO were multiple organ failure, followed by cardiac failure and neurological causes. More than one‐third of V‐A ECMO patients die during ECMO support. Additionally, many of successfully weaned patients still decease during hospital stay, defining the "V‐A ECMO gap." Underreporting and lack of uniformity in reporting of important parameters remains problematic in ECMO research. Future studies should uniformly define timing and causes of death in V‐A ECMO patients to better understand the effectiveness and complications of this support. [ABSTRACT FROM AUTHOR]

Extracorporeal life support (ECLS) is a temporary mechanical assistance method employed in acute respiratory, cardiocirculatory, and cardio‐respiratory failure, refractory to conventional treatments. Patient's hemodynamic, respiratory and metabolic condition, or situations related to ECLS support or performance, may change during ECLS treatment. Provision of an additional drainage or perfusion cannula, or even of an additional associated device, for example, transaortic suction device or intra‐aortic balloon pump (IABP), may be required to improve the ECLS/patient interaction and effects. Besides such a modified ECLS mode, however, a potential asset is represented by the "dynamic ECLS," which is the change of the flow direction (drainage or perfusion) in the already implanted cannula during the ECLS run. This particular management may be achieved in venous femoral or jugular cannulation, but it finds an even more appealing potential with the pulmonary artery (PA) cannulation. The PA allows the institution of a multitasking ECLS circuit, ranging from enhanced left ventricle (LV) unloading (drainage from the PA) to a right ventricular support or "central" veno‐venous ECLS (perfusing the PA), tailored according to the patient hemodynamic, gas exchange, metabolic state, underlying cardiac involvement, and ECLS performance. Dynamic ECLS may, therefore, represent an additional option in ECLS management, particularly including the PA cannulation. Based on this new dynamic management of ECLS mode, we propose the Extracorporeal Life Support Organization nomenclature update. [ABSTRACT FROM AUTHOR]

Commercially available products used for antithrombin supplementation, for example, in extracorporeal life support, may contain latent antithrombin, a hyper-stable strongly procoagulative and anti-angiogenic residue. Latent antithrombin is associated with severe thrombosis in the critically ill. In the manufacturing process of fractionated antithrombin from plasma, heat treatment, citrate, and freeze drying speed up the transformation of native antithrombin to latent antithrombin. Manufacturers are not required to assess and report the latent antithrombin content of their products. When reported, the latent antithrombin fractions in their product range from <1% to 40% of total antithrombin compared with <3% in the healthy adult and less in children. The aims of this work were (1) to convey increased awareness to clinicians who may experience defaulted, expected effect after antithrombin supplementation in, for example, heparin anticoagulation during extracorporeal life support and (2) to urge manufacturers to assess and disclose latent antithrombin content in their products. [ABSTRACT FROM AUTHOR]

With ongoing progress of components of extracorporeal membrane oxygenation including improvements of oxygenators, pumps, and coating materials, extracorporeal membrane oxygenation became increasingly accepted in the clinical practice. A suitable testing in an adequate setup is essential for the development of new technical aspects. Relevant tests can be conducted in ex vivo models specifically designed to test certain aspects. Different setups have been used in the past for specific research questions. We conducted a systematic literature review of ex vivo models of extracorporeal membrane oxygenation components. MEDLINE and Embase were searched between January 1996 and October 2017. The inclusion criteria were ex vivo models including features of extracorporeal membrane oxygenation technology. The exclusion criteria were clinical studies, abstracts, studies in which the model of extracorporeal membrane oxygenation has been reported previously, and studies not reporting on extracorporeal membrane oxygenation components. A total of 50 studies reporting on different ex vivo extracorporeal membrane oxygenation models have been identified from the literature search. Models have been grouped according to the specific research question they were designed to test for. The groups are focused on oxygenator performance, pump performance, hemostasis, and pharmacokinetics. Pre-clinical testing including use of ex vivo models is an important step in the development and improvement of extracorporeal membrane oxygenation components and materials. Furthermore, ex vivo models offer valuable insights for clinicians to better understand the consequences of choice of components, setup, and management of an extracorporeal membrane oxygenation circuit in any given condition. There is a need to standardize the reporting of pre-clinical studies in this area and to develop best practice in their design. [ABSTRACT FROM AUTHOR]

Despite ECMO being a well-accepted and established life-saving support for newborns, prematurity (<34 weeks of gestation) and low birth weight <2.0 kg are still considered relative contraindications due to the fear of intracranial bleeding complications. In the last decades, outcome in extracorporeal life support for pre-term babies has improved, and morbidity dominated by intracranial bleedings has decreased. With the introduction of new methodologies and technological development, the current ELSO guideline for ECMO (GA >34 w, BW > 2.0 kg) deserves to be challenge. The authors suggest that Prem-ECMO (GA 32-33) could be considered when r estricted to experienced high-volume neonatal ECMO centers , with closed monitoring and rigorous reporting to the ELSO registry , providing close targeting of oxygen delivery for prevention of retinopathy and being active participants in continuous development of technology and devices for improved biocompatibility for use in the neonate. [ABSTRACT FROM AUTHOR]

Adequate extracorporeal membrane oxygenation support in the adult requires cannulae permitting blood flows up to 6-8 L/minute. In accordance with Poiseuille's law, flow is proportional to the fourth power of cannula inner diameter and inversely proportional to its length. Poiseuille's law can be applied to obtain the pressure drop of an incompressible, Newtonian fluid (such as water) flowing in a cylindrical tube. However, as blood is a pseudoplastic non-Newtonian fluid, the validity of Poiseuille's law is questionable for prediction of cannula properties in clinical practice. Pressure–flow charts with non-Newtonian fluids, such as blood, are typically not provided by the manufacturers. A standardized laboratory test of return (arterial) cannulae for extracorporeal membrane oxygenation was performed. The aim was to determine pressure–flow data with human whole blood in addition to manufacturers' water tests to facilitate an appropriate choice of cannula for the desired flow range. In total, 14 cannulae from three manufacturers were tested. Data concerning design, characteristics, and performance were graphically presented for each tested cannula. Measured blood flows were in most cases 3-21% lower than those provided by manufacturers. This was most pronounced in the narrow cannulae (15-17 Fr) where the reduction ranged from 27% to 40% at low flows and 5-15% in the upper flow range. These differences were less apparent with increasing cannula diameter. There was a marked disparity between manufacturers. Based on the measured results, testing of cannulae including whole blood flows in a standardized bench test would be recommended. [ABSTRACT FROM AUTHOR]

Venoarterial extracorporeal membrane oxygenation, indicated for severe cardio-respiratory failure, may result in anatomic regional differences in oxygen saturation. This depends on cannulation, hemodynamic state, and severity of respiratory failure. Differential hypoxemia, often discrete, may cause clinical problems in peripheral femoro-femoral venoarterial extracorporeal membrane oxygenation, when the upper body is perfused with low saturated blood from the heart and the lower body with well-oxygenated extracorporeal membrane oxygenation blood. The key is to diagnose and manage fulminant differential hypoxemia, that is, a state that may develop where the upper body is deprived of oxygen. We summarize physiology, assessment of diagnosis, and management of fulminant differential hypoxemia during venoarterial extracorporeal membrane oxygenation. A possible solution is implantation of an additional jugular venous return cannula. In this article, we propose an even better solution, to drain the venous blood from the superior vena cava. Drainage from the superior vena cava provides superiority to venovenoarterial configuration in terms of physiological rationale, efficiency, safety, and simplicity in clinical circuit design. [ABSTRACT FROM AUTHOR]