Year in review: Highlights in ECLS Innovation and Technology, Anno 2022-2023.

BACKGROUND: In the field of extracorporeal life support (ECLS), the rapid influx of novel technologies and innovative techniques presents an ongoing challenge for professionals to stay informed about these advancements. To address this issue and ensure the ECLS community remains up-to-date, we have compiled a concise overview of recent technological innovations in ECLS. PURPOSE: This overview focuses primarily on academically investigated and reported advancements in the ECLS domain. It underscores the importance of transparent communication regarding technological limitations in healthcare and advocates for collaboration between medical professionals and engineers to elevate patient care. RESEARCH DESIGN: This manuscript presents a compilation of recent technological advancements in ECLS, with an emphasis on innovations that have been academically explored and documented. The research approach involves gathering information from scholarly sources, reports, and studies to provide a comprehensive overview. STUDY SAMPLE: The study sample comprises a diverse range of recent technological innovations in the field of extracorporeal life support (ECLS). These innovations span various aspects of ECLS technology and have been investigated and reported on within the academic literature. ANALYSIS: Data collection involved systematically reviewing academic literature, reports, and studies related to recent technological advancements in ECLS. The collected information was then analyzed to identify common trends, notable developments, and the impact of these innovations on patient care. RESULTS: The compilation highlights several significant technological innovations within the ECLS domain. Notable advancements include the development of new dual lumen cannulae, innovative devices for left ventricular (LV) unloading, lightweight ECMO transport systems, streamlined driving consoles to facilitate patient mobility, intricate systems for extracorporeal cardiopulmonary resuscitation (ECPR), standardized driving consoles for networking, and non-invasive circuit pressure monitoring. Some of these innovations have obtained regulatory approvals for distribution in the United States and/or authorization for the European market. CONCLUSIONS: The manuscript underscores the critical role of collaboration between clinicians, researchers, and industry in driving recent technological innovations within the ECLS field. It emphasizes the necessity of open communication about technological limitations and the potential for repurposing established technologies in novel ways. However, the resourcefulness of physicians in repurposing devices requires validation through comprehensive scientific and technical investigation. Thus, fostering broader collaboration among stakeholders is recommended to ensure the rigorous evaluation and validation of new applications for established ECLS devices.

Extracorporeal life support provision in COVID-19 patients - An international EuroELSO 2022 update survey.

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.

ECLS Training and Simulation - Evaluation of the 8th Educational Corner of the EuroELSO Congress 2019 Held in Barcelona.

Introduction: Simulation-based learning and hands-on learning are popular in medicine, particularly in areas where life-saving manoeuvres and team skills are required. Simulations can be provided in different environments: directly in hospitals (in situ), in dedicated facilities (simulation rooms) or, on occasion, at scientific meetings, thus taking advantage of the delegates' motivation. Simulation-based learning in extracorporeal life support is also increasingly relevant due to the inherent features of the often difficult and emergent decision-making, approaches and management involved, as well as to the challenging multidisciplinary teamwork. Aim: Based on these premises and on the constant rise in interest in starting new extracorporeal life support programmes, the EuroELSO organization has, since the beginning of its scientific activities, established an 'ad hoc' space (Educational Corner) for training and hands-on sessions with a limited number of attendees per session during its annual congress. Methods: Experienced trainers deliver repeated dedicated sessions on fundamental aspects of extracorporeal life support management. After several years of sessions, a questionnaire was prepared and delivered to the attendees at the 8th annual congress in Barcelona. Results: More than 90% of the responders indicated that they would recommend the workshop to their colleagues and that they received useful information during the workshops. Over 85% of the responders (85-97%) indicated that the workshops met the set educational goals and objectives and indicated that the simulation sessions would have a positive impact on their daily practice. Conclusion: The Educational Corner during the EuroELSO Congress has achieved great popularity, as shown by the number of attendees participating each year, and presumably improves many technical and behavioural skills among the attendees.

Ex vivo models for research in extracorporeal membrane oxygenation: a systematic review of the literature.

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.

Pressure and flow properties of dual-lumen cannulae for extracorporeal membrane oxygenation.

INTRODUCTION: In the last decade, dual-lumen cannulae have been increasingly applied in patients undergoing extracorporeal life support. Well-performing vascular access is crucial for efficient extracorporeal membrane oxygenation support; thus, guidance for proper cannulae size is required. Pressure-flow charts provided by manufacturers are often based on tests performed using water, rarely blood. However, blood is a shear-thinning and viscoelastic fluid characterized by different flow properties than water. METHODS: We performed a study evaluating pressure-flow curves during standardized conditions using human whole blood in two commonly available dual-lumen cannulae used in neonates, pediatric, and adult patients. Results were merged and compared with the manufacturer's corresponding curves obtained from the public domain. RESULTS: The results showed that using blood as compared with water predominantly influenced drainage flow. A 10-80% higher pressure-drop was needed to obtain same drainage flow (hematocrit of 26%) compared with manufacturer's water charts in 13-31 Fr bi-caval dual-lumen cannulae. The same net difference was found in cavo-atrial cannulae (16-32 Fr), where a lower drainage pressure was required (Hct of 26%) compared with the manufacturer's test using blood with an Hct of 33%. Return pressure-flow data were similar, independent whether pumping blood or water, to the data reported by manufacturers. CONCLUSION: Non-standardized testing of pressure-flow properties of extracorporeal membrane oxygenation dual-lumen cannulae prevents an adequate prediction of pressure-flow results when these cannulae are used in patients. Properties of dual-lumen cannulae may vary between sizes within same cannula family, in particular concerning the drainage flow.

Low-flow assessment of current ECMO/ECCO2R rotary blood pumps and the potential effect on hemocompatibility.

BACKGROUND: Extracorporeal carbon dioxide removal (ECCO2R) uses an extracorporeal circuit to directly remove carbon dioxide from the blood either in lieu of mechanical ventilation or in combination with it. While the potential benefits of the technology are leading to increasing use, there are very real risks associated with it. Several studies demonstrated major bleeding and clotting complications, often associated with hemolysis and poorer outcomes in patients receiving ECCO2R. A better understanding of the risks originating specifically from the rotary blood pump component of the circuit is urgently needed. METHODS: High-resolution computational fluid dynamics was used to calculate the hemodynamics and hemocompatibility of three current rotary blood pumps for various pump flow rates. RESULTS: The hydraulic efficiency dramatically decreases to 5-10% if operating at blood flow rates below 1 L/min, the pump internal flow recirculation rate increases 6-12-fold in these flow ranges, and adverse effects are increased due to multiple exposures to high shear stress. The deleterious consequences include a steep increase in hemolysis and destruction of platelets. CONCLUSIONS: The role of blood pumps in contributing to adverse effects at the lower blood flow rates used during ECCO2R is shown here to be significant. Current rotary blood pumps should be used with caution if operated at blood flow rates below 2 L/min, because of significant and high recirculation, shear stress, and hemolysis. There is a clear and urgent need to design dedicated blood pumps which are optimized for blood flow rates in the range of 0.5-1.5 L/min.

Pressure and flow properties of cannulae for extracorporeal membrane oxygenation II: drainage (venous) cannulae.

The use of extracorporeal life support devices such as extracorporeal membrane oxygenation in adults requires cannulation of the patient's vessels with comparatively large diameter cannulae to allow circulation of large volumes of blood (>5 L/min). The cannula diameter and length are the major determinants for extracorporeal membrane oxygenation flow. Manufacturing companies present pressure-flow charts for the cannulae; however, these tests are performed with water. Aims of this study were 1. to investigate the specified pressure-flow charts obtained when using human blood as the circulating medium and 2. to support extracorporeal membrane oxygenation providers with pressure-flow data for correct choice of the cannula to reach an optimal flow with optimal hydrodynamic performance. Eighteen extracorporeal membrane oxygenation drainage cannulae, donated by the manufacturers (n = 6), were studied in a centrifugal pump driven mock loop. Pressure-flow properties and cannula features were described. The results showed that when blood with a hematocrit of 27% was used, the drainage pressure was consistently higher for a given flow (range 10%-350%) than when water was used (data from each respective manufacturer's product information). It is concluded that the information provided by manufacturers in line with regulatory guidelines does not correspond to clinical performance and therefore may not provide the best guidance for clinicians.

Pressure and flow properties of cannulae for extracorporeal membrane oxygenation I: return (arterial) cannulae.

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.

A narrative review of the technical standards for extracorporeal life support devices (pumps and oxygenators) in Europe.

This review summarizes the European rules to control the market when introducing new products. In particular, it shows all the steps to achieve the European Conformity (CE Mark), a certification that all new medical products must achieve before being used in Europe. Extracorporeal membrane oxygenation (ECMO) devices are exposed to the same procedures. Hereby, we present some regulatory issues regarding pumps and oxygenators, providing technical details as released by the manufacturers on their websites and information charts.

European practices on antithrombotic management during percutaneous mechanical circulatory support in adults: a survey of the Association for Acute CardioVascular Care of the ESC and the European branch of the Extracorporeal Life Support Organization.

AIMS: Bleeding and thrombotic complications compromise outcomes in patients undergoing percutaneous mechanical circulatory support (pMCS) with veno-arterial extracorporeal membrane oxygenation (V-A ECMO) and/or microaxial flow pumps like Impella™. Antithrombotic practices are an important determinant of the coagulopathic risk, but standardization in the antithrombotic management during pMCS is lacking. This survey outlines European practices in antithrombotic management in adults on pMCS, making an initial effort to standardize practices, inform future trials, and enhance outcomes. METHODS AND RESULTS: This online cross-sectional survey was distributed through digital newsletters and social media platforms by the Association of Acute Cardiovascular Care and the European branch of the Extracorporeal Life Support Organization. The survey was available from 17 April 2023 to 23 May 2023. The target population were European clinicians involved in care for adults on pMCS. We included 105 responses from 26 European countries. Notably, 72.4% of the respondents adhered to locally established anticoagulation protocols, with unfractionated heparin (UFH) being the predominant anticoagulant (Impella™: 97.0% and V-A ECMO: 96.1%). A minority of the respondents, 10.8 and 14.5%, respectively, utilized the anti-factor-Xa assay in parallel with activated partial thromboplastin time for UFH monitoring during Impella™ and V-A ECMO support. Anticoagulant targets varied across institutions. Following acute coronary syndrome without percutaneous coronary intervention (PCI), 54.0 and 42.7% were administered dual antiplatelet therapy during Impella™ and V-A ECMO support, increasing to 93.7 and 84.0% after PCI. CONCLUSION: Substantial heterogeneity in antithrombotic practices emerged from participants' responses, potentially contributing to variable device-associated bleeding and thrombotic complications.

Management of Bleeding and Hemolysis During Percutaneous Microaxial Flow Pump Support: A Practical Approach.

Percutaneous ventricular assist devices (pVADs) are increasingly being used because of improved experience and availability. The Impella (Abiomed), a percutaneous microaxial, continuous-flow, short-term ventricular assist device, requires meticulous postimplantation management to avoid the 2 most frequent complications, namely, bleeding and hemolysis. A standardized approach to the prevention, detection, and treatment of these complications is mandatory to improve outcomes. The risk for hemolysis is mostly influenced by pump instability, resulting from patient- or device-related factors. Upfront echocardiographic assessment, frequent monitoring, and prompt intervention are essential. The precarious hemostatic balance during pVAD support results from the combination of a procoagulant state, due to critical illness and contact pathway activation, together with a variety of factors aggravating bleeding risk. Preventive strategies and appropriate management, adapted to the impact of the bleeding, are crucial. This review offers a guide to physicians to tackle these device-related complications in this critically ill pVAD-supported patient population.

ELSO Guidelines for Adult and Pediatric Extracorporeal Membrane Oxygenation Circuits.

DISCLAIMER: This guideline describes the ECMO circuit for all patient populations. These guidelines describe safe practice based on extensive experience and are considered consensus guidelines. These guidelines are not intended to define standard of care and are revised at regular intervals as new information, devices, medications, and techniques become available.

Extracorporeal cardiopulmonary resuscitation in adults: evidence and implications.

Rates of survival with functional recovery for both in-hospital and out-of-hospital cardiac arrest are notably low. Extracorporeal cardiopulmonary resuscitation (ECPR) is emerging as a modality to improve prognosis by augmenting perfusion to vital end-organs by utilizing extracorporeal membrane oxygenation (ECMO) during conventional CPR and stabilizing the patient for interventions aimed at reversing the aetiology of the arrest. Implementing this emergent procedure requires a substantial investment in resources, and even the most successful ECPR programs may nonetheless burden healthcare systems, clinicians, patients, and their families with unsalvageable patients supported by extracorporeal devices. Non-randomized and observational studies have repeatedly shown an association between ECPR and improved survival, versus conventional CPR, for in-hospital cardiac arrest in select patient populations. Recently, randomized controlled trials suggest benefit for ECPR over standard resuscitation, as well as the feasibility of performing such trials, in out-of-hospital cardiac arrest within highly coordinated healthcare delivery systems. Application of these data to clinical practice should be done cautiously, with outcomes likely to vary by the setting and system within which ECPR is initiated. ECPR introduces important ethical challenges, including whether it should be considered an extension of CPR, at what point it becomes sustained organ replacement therapy, and how to approach patients unable to recover or be bridged to heart replacement therapy. The economic impact of ECPR varies by health system, and has the potential to outstrip resources if used indiscriminately. Ideally, studies should include economic evaluations to inform health care systems about the cost-benefits of this therapy.

Heart failure supported by veno-arterial extracorporeal membrane oxygenation (ECMO): a systematic review of pre-clinical models.

OBJECTIVES: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used to treat patients with refractory severe heart failure. Large animal models are developed to help understand physiology and build translational research projects. In order to better understand those experimental models, we conducted a systematic literature review of animal models combining heart failure and VA-ECMO. STUDIES SELECTION: A systematic review was performed using Medline via PubMed, EMBASE, and Web of Science, from January 1996 to January 2019. Animal models combining experimental acute heart failure and ECMO were included. Clinical studies, abstracts, and studies not employing VA-ECMO were excluded. DATA EXTRACTION: Following variables were extracted, relating to four key features: (1) study design, (2) animals and their peri-experimental care, (3) heart failure models and characteristics, and (4) ECMO characteristics and management. RESULTS: Nineteen models of heart failure and VA-ECMO were included in this review. All were performed in large animals, the majority (n = 13) in pigs. Acute myocardial infarction (n = 11) with left anterior descending coronary ligation (n = 9) was the commonest mean of inducing heart failure. Most models employed peripheral VA-ECMO (n = 14) with limited reporting. CONCLUSION: Among models that combined severe heart failure and VA-ECMO, there is a large heterogeneity in both design and reporting, as well as methods employed for heart failure. There is a need for standardization of reporting and minimum dataset to ensure translational research achieve high-quality standards.

Hemolysis in cardiac surgery patients undergoing cardiopulmonary bypass: a review in search of a treatment algorithm.

Hemolysis is a fact in all extracorporeal circuits, as shown in various studies by the increasing levels of plasma-free hemoglobin (PfHb) and decreasing levels of haptoglobin during and after cardiopulmonary bypass (CPB). Beside complete red blood cell (RBC) destruction or hemolysis, RBCs can also be damaged on a sublethal level, resulting in altered rheological properties. Increased levels of free RBC constituents together with an exhaust of their scavengers result in a variety of serious clinical sequela, such as increased systemic and pulmonary vascular resistance, altered coagulation profile, platelet dysfunction, renal tubular damage, and increased mortality. Sublethal RBC damage is characterized by decreased microperfusion and hypoxic RBCs, leading to end organ dysfunction caused by cellular ischemia. Isolated extracorporeal circuit components can be considered non-hemolytic if used according to recommendations, but extracorporeal circuit composition and management during CPB can still be optimized, avoiding cell damaging mechanical forces. Although most RBC destruction in standard CPB remains within the capacity of the endogenous clearing mechanisms, in some cases, levels of PfHb do substantially rise, and precautionary measures need to be taken. Higher degree of hemolysis can be expected in young children, after extensive surgery, and in prolonged support as in patients supported by ventricular assist devices (VADs) or extracorporeal membrane oxygenation (ECMO). These patients are especially susceptible to the toxic influences of unscavenged RBC constituents and the loss of rheologic properties of the RBCs. Considering the high percentage of neurologic and renal sequela in post-cardiotomy patients, all imbalances possibly contributing to these morbidities should be focused on and prevented, if not treated. Considering the severity of the consequences of RBC damage, the high incidence of this complication, and especially the lack of interventional strategies in cases of suspected or confirmed RBC damage, there may be a need for a treatment algorithm for this phenomenon.

Extracorporeal CO2 removal in critically ill patients: a systematic review.

INTRODUCTION: The use of extracorporeal CO2 removal (ECCO2R) is increasingly employed in critically ill patients. However, the clinical evidence supporting its efficacy remains currently poor. EVIDENCE ACQUISITION: A systematic review using MEDLINE via PubMed was performed to identify eligible studies (until 30th September 2016). The amount of CO2 reduction, the effect on the duration of mechanical ventilation and weaning, the impact on patients' outcome and the occurrence of complications were evaluated. The quality of evidence was evaluated according to the GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. EVIDENCE SYNTHESIS: Six studies were included (three evaluating patients with chronic obstructive pulmonary disease [COPD]; three evaluating patients with acute respiratory distress syndrome [ARDS]), involving 279 adult patients; 142 treated with ECCO2R and 137 controls. No study on pediatric population met the inclusion criteria for analysis. The overall quality of evidence of the two randomized trials and four case-control studies varied from moderate to very low. PaCO2 was generally reduced by 25-33% within a few hours following ECCO2R initiation. One ARDS study showed a significant decrease in the duration of mechanical ventilation, although this result was only found by post-hoc analysis. The three studies on COPD demonstrated that some patients supported by ECCO2R devices could avoid endotracheal intubation, however the ICU-LOS and survival was not influenced by ECCO2R when compared to controls. CONCLUSIONS: In COPD patients, a significantly reduced need for endotracheal intubation was reported. However, the use of ECCO2R has not shown significant improvement on the outcome of critically ill patients in the reviewed studies. Therefore appropriately powered, randomized, controlled studies are urgently needed.