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Refractory septic shock is associated with a high risk of death. Circulatory support in the form of veno-arterial extracorporeal membrane oxygenation (VA ECMO) may function as a bridge to recovery, allowing for the treatment of the source of the sepsis. Whilst VA ECMO has been accepted as the means of hemodynamic support for children, in adults, single center observational studies show survival rates of only 70–90% for hypodynamic septic shock. The use of VA ECMO for circulatory support in hyperdynamic septic shock with preserved cardiac output or when applied late during cardio-pulmonary resuscitation is not recommended. With unresolving septic shock and a loss of ventriculo–arterial coupling, stress cardiomyopathy often develops. If the cardiac index (CI) approaches subnormal levels (CI < 2.5 L/min m−2) that do not match low systemic vascular resistance with a resulting loss of vital systemic perfusion pressure, VA ECMO support should be considered. A further decrease to the level of cardiogenic shock (CI < 1.8 L/min m−2) should be regarded as an indication for VA ECMO insertion. For patients who maintain a normal-to-high CI as part of their refractory vasoparalysis, VA ECMO support is justified in children and possibly in patients with a low body mass index. Extracorporeal support for septic shock should be limited to high-volume ECMO centers. [ABSTRACT FROM AUTHOR]

Aim: Risk of treatment-related life-threatening toxicity is high in childhood acute myeloid leukaemia (AML), and access to intensive care units (ICU) is crucial. We explored the ICU admission rate and outcome after intensive care in childhood AML in Sweden. Methods: Patients diagnosed between 2008 and 2016 were identified from the Swedish Childhood Cancer Registry (SCCR), a national quality registry. Data from SCCR was cross-referenced with clinical questionnaire data from paediatric oncology centers and the Swedish Intensive Care Registry (SIR), another national quality registry. Results: According to combined data, 46% of the children (58/126) were admitted to ICU, 17% (21/126) within 1 month from diagnosis. Overall, ICU mortality per admission was 12% and 6% during first-line treatment. There was a discrepancy between admission rate from the clinical questionnaires and SCCR (29%; 36/126 children) and SIR (44%; 55/126) All deaths during first-line treatment occurred at or after ICU care. Conclusion: Although admission rate under AML treatment was high, the treatment-related mortality under first-line treatment was low. No child died under first-line treatment without admission to ICU, suggesting good availability. The discrepancy between the two registries, SCCR and SIR, highlights the need for future validation of registry data. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: General selenium supplementation to intensive care unit (ICU) patients in regions with selenium-rich soil does not improve outcomes. Still selenium supplementation may reduce morbidity and mortality in patients with low-serum selenium concentration (S-Se) in selenium-poor areas who respond to treatment. The primary aim of this observational study was to investigate S-Se in a selenium-deficient region at time of intensive care admission, and in addition to monitor S-Se during high-dose selenium supplementation for safety.Methods: We measured S-Se in 100 consecutive patients admitted to a tertiary general ICU. After initial sampling, high-dose intravenous (iv) selenium supplementation was administered up to 20 days.Results: At admission, in 95% of the cases, S-Se was below the saturation level for selenoenzymes, in 91%, below the Swedish reference level, and in 71%, below the level where selenoenzyme function may be impaired. At day 5 of substitution, all patients still remaining in the ICU (n = 26) were within the range for enzyme function, 12% were below reference, and 24% did not reach full enzymatic saturation. At day 10 and forward, all patients were within target for treatment. No patients were at risk for toxic S-Se concentration.Conclusions: S-Se concentration was substantially lower compared to normal values at ICU admission in this cohort of unselected Swedish critical care patients. Selenium supplementation restituted S-Se to levels corresponding to enzymatic saturation and the Swedish reference interval for all subjects remaining in the ICU on day 5. [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]

Extracorporeal life support (ECLS) includes life-saving support in severe acute cardiac and/or pulmonary failure. In the past 20 years, centrifugal pumps have become the primary choice to deliver the required blood flow. Pumps of various designs, with different approved operating ranges, are today available to clinicians. The use of centrifugal pumps in the low flow condition has been shown to increase hemolytic and thrombogenic risks of the treatment. Further, low flow operation has been associated with retrograde flow at the pump inlet. In this study, experimental and numerical methods have been applied to investigate the operating conditions and fluid dynamical mechanisms leading to reverse flow (or backflow) at the inlet. Reverse flow was predominantly observed in pumps having a top shroud covering the impeller blades, showing a relation between pump geometry and backflow. The shroud divides the pump volume above the impeller into two regions, separating the swirling reverse flow migrating toward the upper pump volute from the main flow, reducing the dissipation of the vortical structures, and allowing the swirling reverse flow to reach further in the pump inlet. At the inlet, backflow was observed as stable recirculation areas at the side of the pump inlet. [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]

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. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation is a life-saving support therapy in the case of cardiopulmonary refractory failure. Its use is associated to complications due to the presence of artificial surfaces and supraphysiological stress conditions. Thus, knowledge of the fluid structures associated to each component can give insight into sources of blood damage. In this study, an experimentally validated numerical study of a conventional lighthouse tip cannula in return configuration was carried out to characterize the flow structures using water or a Newtonian blood analog with different flow rate ratios and cannula positioning and their influence on hemolysis. The results showed that strong shear layers developed where the jets from the side holes met the co-flow. Stationary backflow regions at the vessel wall were also present downstream of the cannula. In the tilted case, the recirculation was much more pronounced on the wide side and almost absent on the narrow side. Small vortical backflow structures developed at the side holes which behaved like obstacles to the co-flow, creating pairs of counter-rotating vortices, which induced locally higher risk of hemolysis. However, global hemolysis index did not show significant deviations. Across the examined flow rate ratios, the holes on the narrow side consistently reinfused a larger fraction of fluid. A radial force developed in the tilted case in a direction so as to recenter the cannula in the vessel. [ABSTRACT FROM AUTHOR]

Key Clinical Message We report a 17-year-old woman with bronchiolitis obliterans-organizing pneumonia ( BOOP)-like granulomatosis with polyangiitis developing severe airway obliterations. Pending age, phase and grade of autoimmune treatment, and offering ECMO treatment may be crucial for survival but occasionally preface futility. ECMO-treated patient with BOOP-like GPA has never been described before. [ABSTRACT FROM AUTHOR]

Background: Extracorporeal membrane oxygenation is a life‐saving therapy used in case of acute respiratory/circulatory failure. Exposure of blood to non‐physiological surfaces and high shear stresses is related to hemolytic damage and platelet activation. A detailed knowledge of the fluid dynamics of the components under different scenarios is thus paramount to assess the thrombogenicity of the circuit. Methods: An investigation of the flow structures developing in a conventional lighthouse tip (single‐staged) drainage cannula was performed with cross‐validated computational fluid dynamics and particle image velocimetry. The aim was to quantify the variation in drainage performance and stress levels induced by different fluid models, hematocrit and vessel‐to‐cannula flow rate ratios. Results: The results showed that the 90° bends of the flow through the side holes created a recirculation zone inside the cannula which increased residence time. Flow structures resembling a jet in a crossflow were also observed. The use of different hematocrits did not significantly affect drainage performances. The most proximal set of holes drained the largest fraction of fluid. However, different flow rate ratios altered the flow rate drained through the tip. The use of 2D data led to a 50% underestimation of shear rate levels. In the drainage zone the non‐Newtonian behavior of blood was less relevant. Conclusions: The most proximal holes drained the largest amount of fluid. The flow features and distribution of flow rates among the holes showed little dependence on the hematocrit. The non‐Newtonian behavior of blood had a small influence on the dynamics of the flow. [ABSTRACT FROM AUTHOR]

Venovenous extracorporeal membrane oxygenation is used for respiratory support in the most severe cases of acute respiratory distress syndrome. Blood is drained from the large veins, oxygenated in an artificial lung, and returned to the right atrium (RA). In this study, we have used large eddy simulations to simulate a single-stage "lighthouse" drainage cannula in a patient-averaged model of the large veins and RA, including the return cannula. We compared the results with previous experimental and numerical studies of these cannulas in idealized tube geometries. According to the simulations, wall proximity at the drainage holes and the presence of the return cannula greatly increased drainage through the tip (33% at 5 L/min). We then simulated a multi-stage device in the same patient-averaged model, showing similar recirculation performance across the range of extracorporeal membrane oxygenation (ECMO) flow rates compared to the lighthouse cannula. Mean and maximum time-averaged wall shear stress were slightly higher for the lighthouse design. At high ECMO flow rates, the multi-stage device developed a negative caval pressure, which may be a cause of drainage obstruction in a clinical environment. Finally, through calculation of the energy spectra and vorticity field, we observed ring-like vortices inside the cannula originating from the side holes, most prominent in the proximal position. Our work highlights the important differences between a patient-derived and simplified venous model, with the latter tending to underestimate tip drainage. We also draw attention to the different dynamics of single-stage and multistage drainage cannulas, which may guide clinical use. [ABSTRACT FROM AUTHOR]

Limb ischaemia is a clinically relevant complication of venoarterial extracorporeal membrane oxygenation (VA ECMO) with femoral artery cannulation. No selective distal perfusion or other advanced techniques were used in the past to maintain adequate distal limb perfusion. A more recent trend is the shift from the reactive or emergency management to the pro-active or prophylactic placement of a distal perfusion cannula to avoid or reduce limb ischaemia-related complications. Multiple alternative cannulation techniques to the distal perfusion cannula have been developed to maintain distal limb perfusion, including end-to-side grafting, external or endovascular femoro-femoral bypass, retrograde limb perfusion (e.g., via the posterior tibial, dorsalis pedis or anterior tibial artery), and, more recently, use of a bidirectional cannula. Venous congestion has also been recognized as a potential contributing factor to limb ischaemia development and specific techniques have been described with facilitated venous drainage or bilateral cannulation being the most recent, to reduce or avoid venous stasis as a contributor to impaired limb perfusion. Advances in monitoring techniques, such as nearinfrared spectroscopy and duplex ultrasound analysis, have been applied to improve decision-making regarding both the monitoring and management of limb ischaemia. This narrative review describes the evolution of techniques used for distal limb perfusion during peripheral VA ECMO. [ABSTRACT FROM AUTHOR]

Background: Extracorporeal membrane oxygenation (ECMO) is indicated for patients with severe respiratory and/or circulatory failure. The standard technique to visualize the extent of pulmonary damage during ECMO is computed tomography (CT). Purpose: This single-center, retrospective study investigated whether pulmonary blood flow (PBF) measured with echocardiography can assist in assessing the extent of pulmonary damage and whether echocardiography and CT findings are associated with patient outcomes. Methods: All patients (>15 years) commenced on ECMO between 2011 and 2017 with septic shock of pulmonary origin and a treatment time >28 days were screened. Of 277 eligible patients, 9 were identified where both CT and echocardiography had been consecutively performed. Results: CT failed to indicate any differences in viable lung parenchyma within or between survivors and non-survivors at any time during ECMO treatment. Upon initiation of ECMO, the survivors (n = 5) and non-survivors (n = 4) had similar PBF. During a full course of ECMO support, survivors showed no change in PBF (3.8 ± 2.1 at ECMO start vs. 7.9 ± 4.3 L/min, p = 0.12), whereas non-survivors significantly deteriorated in PBF from 3.5 ± 1.0 to 1.0 ± 1.1 L/min (p = 0.029). Tidal volumes were significantly lower over time among the non-survivors, p = 0.047. Conclusions: In prolonged ECMO for pulmonary septic shock, CT was not found to be effective for the evaluation of pulmonary viability or recovery. This hypothesis-generating investigation supports echocardiography as a tool to predict pulmonary recovery via the assessment of PBF at the early to later stages of ECMO support. [ABSTRACT FROM AUTHOR]

Extracorporeal life support (ECLS) is a means to support patients with acute respiratory failure. Initially, recommendations to treat severe cases of pandemic coronavirus disease 2019 (COVID‐19) with ECLS have been restrained. In the meantime, ECLS has been shown to produce similar outcomes in patients with severe COVID‐19 compared to existing data on ARDS mortality. We performed an international email survey to assess how ECLS providers worldwide have previously used ECLS during the treatment of critically ill patients with COVID‐19. A questionnaire with 45 questions (covering, e.g., indication, technical aspects, benefit, and reasons for treatment discontinuation), mostly multiple choice, was distributed by email to ECLS centers. The survey was approved by the European branch of the Extracorporeal Life Support Organization (ELSO); 276 ECMO professionals from 98 centers in 30 different countries on four continents reported that they employed ECMO for very severe COVID‐19 cases, mostly in veno‐venous configuration (87%). The most common reason to establish ECLS was isolated hypoxemic respiratory failure (50%), followed by a combination of hypoxemia and hypercapnia (39%). Only a small fraction of patients required veno‐arterial cannulation due to heart failure (3%). Time on ECLS varied between less than 2 and more than 4 weeks. The main reason to discontinue ECLS treatment prior to patient's recovery was lack of clinical improvement (53%), followed by major bleeding, mostly intracranially (13%). Only 4% of respondents reported that triage situations, lack of staff or lack of oxygenators, were responsible for discontinuation of ECLS support. Most ECLS physicians (51%, IQR 30%) agreed that patients with COVID‐19‐induced ARDS (CARDS) benefitted from ECLS. Overall mortality of COVID‐19 patients on ECLS was estimated to be about 55%. ECLS has been utilized successfully during the COVID‐19 pandemic to stabilize CARDS patients in hypoxemic or hypercapnic lung failure. Age and multimorbidity limited the use of ECLS. Triage situations were rarely a concern. ECLS providers stated that patients with severe COVID‐19 benefitted from ECLS. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation (ECMO) is a life-supportive treatment in neonatal patients with refractory lung and/or heart failure. Intracranial hemorrhage (ICH) is a severe complication and reliable predictors are warranted. The aims of this study were to explore the incidence and possible predictors of ICH in ECMO-treated neonatal patients. We performed a single-center retrospective observational cohort study. Patients aged ≤ 28 days treated with ECMO between 2010 and 2018 were included. Exclusion criteria were ICH, ischemic stroke, cerebrovascular malformation before ECMO initiation or detected within 12 h of admission, ECMO treatment < 12 h, or prior treatment with ECMO at another facility > 12 h. The primary outcome was a CT-verified ICH. Logistic regression models were employed to identify possible predictors of the primary outcome. Of the 223 patients included, 29 (13%) developed an ICH during ECMO treatment. Thirty-day mortality was 59% in the ICH group and 16% in the non-ICH group (p < 0.0001). Lower gestational age (p < 0.01, odds ratio (OR) 0.96; 95%CI 0.94–0.98), and higher pre-ECMO lactate levels (p = 0.017, OR 1.1; 95%CI 1.01–1.18) were independently associated with increased risk of ICH-development. In the clinical setting, identification of risk factors and multimodal neuromonitoring could help initiate steps that lower the risk of ICH in these patients. [ABSTRACT FROM AUTHOR]

Background: Patients with multiple organ failure (MOF) often receive large amounts of resuscitation fluid, making them at high risk of fluid overload (FO). Our main objective was to investigate if the ability to achieve a negative fluid balance during the first 3 continuous renal replacement therapy (CRRT) days was associated with mortality in children with MOF.Methods: Retrospective cohort study in a tertiary multidisciplinary academic paediatric hospital. The study included 63 patients (age 0-18 years) with 3 or more failing organs receiving CRRT due to acute kidney injury and/or fluid overload.Results: The median age was 4 months, and PICU mortality was 29%. Survivors had significantly lower degree of FO at CRRT initiation, (median 15% (Interquartile range 9-22)) than non-survivors (24% (17%-37%), P = 0.002). On PICU admission, PIM-3 score was significantly higher in non-survivors (P = 0.01), but at CRRT initiation there was no difference in PELOD-2 score (P = 0.98). Mortality in patients achieving a cumulative net negative fluid balance during the first 3 days after CRRT initiation was 12%, compared to 86% in those not achieving this (P < 0.0001). In multivariate analysis, the inability to achieve a net negative fluid balance during 3 days after CRRT initiation (P < 0.0001) and FO >20% at CRRT initiation (P = 0.0019) remained associated with mortality.Conclusion: Our results suggest that early fluid removal is associated with improved patient outcome in critically ill children receiving CRRT, and that prompt measures should be taken to prevent fluid overload in critical illness. These results need to be verified in further, prospective studies. [ABSTRACT FROM AUTHOR]

Objectives: Septic shock carries a high mortality risk. Studies have indicated that patients with septic shock may benefit from extracorporeal membrane oxygenation. In most studies, patients exhibited shock due to myocardial dysfunction rather than distributive/vasoplegic shock. One proposed theory is that venoarterial extracorporeal membrane oxygenation alleviates a failing myocardial function.Design: Retrospective observational study.Setting: Single-center, high-volume extracorporeal membrane oxygenation unit.Patients: All patients treated for septic shock between 2012 and 2017 with an age greater than 18 years old, fulfilling septic shock criteria according to "Sepsis-3" at acceptance for extracorporeal membrane oxygenation, presence of cardiocirculatory failure requiring a support equivalent to a Vasoactive Inotropic Score greater than 50 to reach a mean arterial pressure greater than 65 mm Hg despite adequate fluid resuscitation, were included.Interventions: None.Measurements and Main Results: Thirty-seven patients, mean age 54.7 years old, were included. Median Simplified Acute Physiology Score-3 score was 86 and Sequential Organ Failure Assessment 16. Twenty-seven patients were submitted to venoarterial and 10 patients to venovenous extracorporeal membrane oxygenation. Hospital survival was 90% for septic shock with left ventricular failure and 64.7% in patients with distributive shock. At long-term follow-up at 46.1 months, total survival was 59.5%. Commencement of venovenous extracorporeal membrane oxygenation and more organ failures at admission showed a less favorable outcome in terms of hospital and long-term survival.Conclusions: The current results add not only to the growing evidence of the benefit of venoarterial extracorporeal membrane oxygenation for septic cardiomyopathy but also indicate improved hospital survival in distributive septic shock. [ABSTRACT FROM AUTHOR]

Venovenous extracorporeal membrane oxygenation (ECMO) can be performed with two single lumen cannulas (SLCs) or one dual-lumen cannula (DLC) where low recirculation fraction ( R f ) is a key performance criterion. DLCs are widely believed to have lower R f , though these have not been directly compared. Similarly, correct positioning is considered critical although its impact is unclear. We aimed to compare two common bi-caval DLC designs and quantify R f in several positions. Two different commercially available DLCs were sectioned, measured, reconstructed, scaled to 27Fr and simulated in our previously published patient-averaged computational model of the right atrium (RA) and venae cavae at 2–6 L/min. One DLC was then used to simulate ± 30° and ± 60° rotation and ± 4 cm insertion depth. Both designs had low R f (< 7%) and similar SVC/IVC drainage fractions and pressure drops. Both cannula reinfusion ports created a high-velocity jet and high shear stresses in the cannula (> 413 Pa) and RA (> 52 Pa) even at low flow rates. Caval pressures were abnormally high (16.2–23.9 mmHg) at low flow rates. Rotation did not significantly impact R f . Short insertion depth increased R f (> 31%) for all flow rates whilst long insertion only increased R f at 6 L/min (24%). Our results show that DLCs have lower R f compared to SLCs at moderate-high flow rates (> 4 L/min), but high shear stresses. Obstruction from DLCs increases caval pressures at low flow rates, a potential reason for increased intracranial hemorrhages. Cannula rotation does not impact R f though correct insertion depth is critical. [ABSTRACT FROM AUTHOR]

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]

Background: Adverse neurological events during extracorporeal membrane oxygenation (ECMO) are common and may be associated with devastating consequences. Close monitoring, early identification and prompt intervention can mitigate early and late neurological morbidity. Neuromonitoring and neurocognitive/neurodevelopmental follow-up are critically important to optimize outcomes in both adults and children. Objective: To assess current practice of neuromonitoring during ECMO and neurocognitive/neurodevelopmental follow-up after ECMO across Europe and to inform the development of neuromonitoring and follow-up guidelines. Methods: The EuroELSO Neurological Monitoring and Outcome Working Group conducted an electronic, web-based, multi-institutional, multinational survey in Europe. Results: Of the 211 European ECMO centres (including non-ELSO centres) identified and approached in 23 countries, 133 (63%) responded. Of these, 43% reported routine neuromonitoring during ECMO for all patients, 35% indicated selective use, and 22% practiced bedside clinical examination alone. The reported neuromonitoring modalities were NIRS (n = 88, 66.2%), electroencephalography (n = 52, 39.1%), transcranial Doppler (n = 38, 28.5%) and brain injury biomarkers (n = 33, 24.8%). Paediatric centres (67%) reported using cranial ultrasound, though the frequency of monitoring varied widely. Before hospital discharge following ECMO, 50 (37.6%) reported routine neurological assessment and 22 (16.5%) routinely performed neuroimaging with more paediatric centres offering neurological assessment (65%) as compared to adult centres (20%). Only 15 (11.2%) had a structured longitudinal follow-up pathway (defined followup at regular intervals), while 99 (74.4%) had no follow-up programme. The majority (n = 96, 72.2%) agreed that there should be a longitudinal structured follow-up for ECMO survivors. Conclusions: This survey demonstrated significant variability in the use of different neuromonitoring modalities during and after ECMO. The perceived importance of neuromonitoring and follow-up was noted to be very high with agreement for a longitudinal structured follow-up programme, particularly in paediatric patients. Scientific society endorsed guidelines and minimum standards should be developed to inform local protocols. [ABSTRACT FROM AUTHOR]

Purpose: This scoping review aims to identify and describe knowledge gaps and research priorities in veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Methods: An expert panel was recruited consisting of eight international experts from different backgrounds. First, a list of priority topics was made. Second, the panel developed structured questions using population, intervention, comparison and outcomes (PICO) format. All PICOs were scored and prioritized. For every selected PICO, a structured literature search was performed. Results: After an initial list of 49 topics, eight were scored as high-priority. For most of these selected topics, current literature is limited to observational studies, mainly consisting of retrospective cohorts. Only for ECPR and anticoagulation, randomized controlled trials (RCTs) have been performed or are ongoing. Per topic, a summary of the literature is stated including recommendations for further research. Conclusions: This scoping review identifies and presents an overview of knowledge gaps and research priorities in VA-ECMO. Current literature is mostly limited to observational studies, although with increasing attention for this patient population, more RCTs are finishing or ongoing. Translational research, from preclinical trials to high-quality or randomized controlled trials, is important to improve the standard practices in this critically ill patient population. Take-home message This scoping review identifies and presents an overview of research gaps and priorities in VA-ECMO. Translational research, from preclinical trials to high-quality or randomized controlled trials, is important to improve the standard practices in this critically ill patient population. [ABSTRACT FROM AUTHOR]

Venovenous extracorporeal membrane oxygenation is a treatment for acute respiratory distress syndrome. Femoro-atrial cannulation means blood is drained from the inferior vena cava and returned to the superior vena cava; the opposite is termed atrio-femoral. Clinical data comparing these two methods is scarce and conflicting. Using computational fluid dynamics, we aim to compare atrio-femoral and femoro-atrial cannulation to assess the impact on recirculation fraction, under ideal conditions and several clinical scenarios. Using a patient-averaged model of the venae cavae and right atrium, commercially-available cannulae were positioned in each configuration. Additionally, occlusion of the femoro-atrial drainage cannula side-holes with/without reduced inferior vena cava inflow (0–75%) and retraction of the atrio-femoral drainage cannula were modelled. Large-eddy simulations were run for 2-6L/min circuit flow, obtaining time-averaged flow data. The model showed good agreement with clinical atrio-femoral recirculation data. Under ideal conditions, atrio-femoral yielded 13.5% higher recirculation than femoro-atrial across all circuit flow rates. Atrio-femoral right atrium flow patterns resembled normal physiology with a single large vortex. Femoro-atrial cannulation resulted in multiple vortices and increased turbulent kinetic energy at > 3L/min circuit flow. Occluding femoro-atrial drainage cannula side-holes and reducing inferior vena cava inflow increased mean recirculation by 11% and 32%, respectively. Retracting the atrio-femoral drainage cannula did not affect recirculation. These results suggest that, depending on drainage issues, either atrio-femoral or femoro-atrial cannulation may be preferrable. Rather than cannula tip proximity, the supply of available venous blood at the drainage site appears to be the strongest factor affecting recirculation. [ABSTRACT FROM AUTHOR]

Extracorporeal cardiopulmonary resuscitation (ECPR) is a rescue therapy for refractory cardiac arrest, but its high mortality has raised questions about patient selection. No selection criteria have been proposed for patients experiencing in-hospital cardiac arrest. We aimed to identify selection criteria available at the time ECPR was considered for patients with in-hospital cardiac arrest. We analyzed data of in-hospital cardiac arrest patients undergoing ECPR in our extracorporeal membrane oxygenation (ECMO) center (March 2007 to March 2019). Intensive care unit (ICU) and 1-year survival post-hospital discharge were assessed. Factors associated with ICU survival before ECPR were investigated. An external validation cohort from a previous multicenter study was used to validate our results. Among the 137 patients (67.9% men; median [IQR] age, 54 [43–62] years; low-flow duration, 45 [30–70] min) requiring ECPR, 32.1% were weaned-off ECMO. Their respective ICU- and 1-year survival rates were 21.9% and 19%. Most 1-year survivors had favorable neurological outcomes (cerebral performance category score 1 or 2). ICU survivors compared to nonsurvivors, respectively, were more likely to have a shockable initial rhythm (53.3% versus 24.3%; P < 0.01), a shorter median (IQR) low-flow time (30 (25–53) versus 50 (35–80) min, P < 0.01) and they more frequently underwent a subsequent intervention (63.3% versus 26.2%, P < 0.01). The algorithm obtained by combining age, initial rhythm and low-flow duration discriminated between patient groups with very different survival probabilities in the derivation and validation cohorts. Survival of ECPR-managed in-hospital cardiac arrest patients in this cohort was poor but hospital survivors' 1-year neurological outcomes were favorable. When deciding whether or not to use ECPR, the combination of age, initial rhythm and low-flow duration can improve patient selection. • This cohort study gathered 137 patients with refractory in-hospital cardiac arrest requiring ECPR. • 1-year survival was 19% and most of survivors had favorable neurological outcome. • An algorithm based on age, initial rhythm (shockable or not) and low-flow duration identifies among patients those with the highest–as well as those with the lowest– probability of survival. [ABSTRACT FROM AUTHOR]

In‐hospital mortality of adult veno‐venous extracorporeal membrane oxygenation (V‐V ECMO) patients remains invariably high. However, little is known regarding timing and causes of in‐hospital death, either on‐ECMO or after weaning. The current review aims to investigate the timing and causes of death of adult patients during hospital admittance for V‐V ECMO, and to define the V‐V ECMO gap, which is represented by the patients that are successfully weaned of ECMO but still die during hospital stay. A systematic search was performed using electronic MEDLINE and EMBASE databases through PubMed. Studies reporting on adult V‐V ECMO patients from January 2006 to December 2020 were screened. Studies that did not report on at least on‐ECMO mortality and discharge rate were excluded from analysis as they could not provide the required information regarding the proposed V‐V ECMO‐gap. Mortality rates on‐ECMO and after weaning, as well as weaning and discharge rates, were analyzed as primary outcomes. Secondary outcomes were the causes of death and complications. Initially, 35 studies were finally included in this review. Merely 24 of these studies (comprising 975 patients) reported on prespecified V‐V ECMO outcomes (on‐ECMO mortality and discharge rate). Mortality on V‐V ECMO support was 27.8% (95% confidence interval (CI) 22.5%‐33.2%), whereas mortality after successful weaning was 12.7% (95% CI 8.8%‐16.6%, defining the V‐V ECMO gap). 72.2% of patients (95% CI 66.8%‐77.5%) were weaned successfully from support and 56.8% (95% CI 49.9%‐63.8%) of patients were discharged from hospital. The most common causes of death on ECMO were multiple organ failure, bleeding, and sepsis. Most common causes of death after weaning were multiorgan failure and sepsis. Although the majority of patients are weaned successfully from V‐V ECMO support, a significant proportion of subjects still die during hospital stay, defining the V‐V ECMO gap. Overall, timing and causes of death are poorly reported in current literature. Future studies on V‐V ECMO should describe morbidity and mortality outcomes in more detail in relation to the timing of the events, to improve patient management, due to enhanced understanding of the clinical course. [ABSTRACT FROM AUTHOR]

• Lower cardiac output increases recirculation in VV ECMO. • The ratio of cardiac output to ECMO flow rate is strongly correlated with recirculation fraction. • VV ECMO return cannulas expose blood to high shear stress (>10 Pa) at any ECMO flow rate. : Increasingly, computational fluid dynamics (CFD) is helping explore the impact of variables like: cannula design/size/position/flow rate and patient physiology on venovenous (VV) extracorporeal membrane oxygenation (ECMO). Here we use a CFD model to determine what role cardiac output (CO) plays and to analyse return cannula dynamics. : Using a patient-averaged model of the right atrium and venae cava, we virtually inserted a 19Fr return cannula and a 25Fr drainage cannula. Running large eddy simulations, we assessed cardiac output at: 3.5–6.5 L/min and ECMO flow rate at: 2–6 L/min. We analysed recirculation fraction (R f), time-averaged wall shear stress (TAWSS), pressure, velocity, and turbulent kinetic energy (TKE) and extracorporeal flow fraction (EFF = ECMO flow rate/CO). : Increased ECMO flow rate and decreased CO (high EFF) led to increased R f (R = 0.98, log fit). Negative pressures developed in the venae cavae at low CO and high ECMO flow (high CR). Mean return cannula TAWSS was >10 Pa for all ECMO flow rates, with majority of the flow exiting the tip (94.0–95.8 %). : Our results underpin the strong impact of CO on VV ECMO. A simple metric like EFF, once supported by clinical data, might help predict R f for a patient at a given ECMO flow rate. The return cannula imparts high shear stresses on the blood, largely a result of the internal diameter. [ABSTRACT FROM AUTHOR]

Background: The objective was to assess predictors for unfavorable neurological outcome (UO) in out-of-hospital (OHCA) and in-hospital (IHCA) cardiac arrest patients treated with Extracorporeal cardiopulmonary resuscitation (ECPR).Methods: A post hoc analysis of retrospective data from five European ECPR centers (January 2012-December 2016) was performed. The primary composite endpoint was 3-month UO defined as survival with a cerebral performance category (CPC) of 3-4 or death (CPC 5).Results: A total of 413 patients treated with ECPR were included (median age was 57 [48-65] years, male gender 78%): 61% of patients (n = 250) suffered OHCA. The median time from collapse to ECMO placement was 63 [45-82] minutes. Overall, 81% patients (n = 333) showed unfavorable UO, which was higher in OHCA patients (90% vs 66%), as compared to IHCA. In OHCA, prolonged time from collapse to ECMO initiation (OR 1.02, p < 0.01) and higher ECMO blood flow (OR 1.99, p = 0.01) were associated with UO while initial shockable rhythm (OR 0.04, p < 0.01), previous heart disease (OR 0.20, p < 0.01) and pre-hospital hypothermia (OR 0.08, p < 0.01) had a protective role. In IHCA, prolonged time from arrest to ECMO implantation (OR 1.02, p = 0.03), high lactate level on admission (OR 1.15, p < 0.01) and higher body weight (OR 1.03, p < 0.01) were independently associated with UO.Conclusions: IHCA and OHCA patients receiving ECPR have different predictors of UO at presentation, suggesting that selection criteria for ECPR should be decided according to the location of CA. After ECMO initiation, ECMO blood flow management and mean arterial pressure targets might also impact neurological recovery. [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 membrane oxygenation (ECMO) is increasingly used to treat cardiopulmonary failure in critically ill patients. Peripheral cannulation may be complicated by a persistent low cardiac output in case of veno-venous cannulation (VV-ECMO) or by differential hypoxia (e.g., lower PaO2 in the upper than in the lower body) in case of veno-arterial cannulation (VA-ECMO) and severe impairment of pulmonary function associated with cardiac recovery. The treatment of such complications remains challenging. We report the early effects of the use of veno-arterial-venous (V-AV) ECMO in this setting. Methods: Retrospective analysis including patients from five different European ECMO centers (January 2013 to December 2016) who required V-AV ECMO. We collected demographic data as well as comorbidities and ECMO characteristics, hemodynamics, and arterial blood gas values before and immediately after (i.e., within 2 h) V-AV implementation. Results: A total of 32 patients (age 53 (interquartiles, IQRs: 31–59) years) were identified: 16 were initially supported with VA-ECMO and 16 with VV-ECMO. The median time to V-AV conversion was 2 (1–5) days. After V-AV implantation, heart rate and norepinephrine dose significantly decreased, while PaO2 and SaO2 significantly increased compared to baseline values. Lactate levels significantly decreased from 3.9 (2.3–7.1) to 2.8 (1.4–4.4) mmol/L (p = 0.048). A significant increase in the overall ECMO blood flow (from 4.5 (3.8–5.0) to 4.9 (4.3–5.9) L/min; p < 0.01) was observed, with 3.0 (2.5–3.2) L/min for the arterial and 2.8 (2.1–3.6) L/min for the venous return flows. Conclusions: In ECMO patients with differential hypoxia or persistently low cardiac output syndrome, V-AV conversion was associated with improvement in some hemodynamic and respiratory parameters. A significant increase in the overall ECMO blood flow was also observed, with similar flow distributed into the arterial and venous return cannulas. [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]

Non-hemorrhagic brain infarction (BI) is a recognized complication in adults treated with extracorporeal membrane oxygenation (ECMO) and associated with increased mortality. However, predictors of BI in these patients are poorly understood. The aim of this study was to identify predictors of BI in ECMO-treated adult patients. We conducted an observational cohort study of all adult patients treated with venovenous or venoarterial (VA) ECMO at our center between 2010 and 2018. The primary endpoint was a computed tomography (CT) verified BI. Logistic regression models were employed to identify BI predictors. In total, 275 patients were included, of whom 41 (15%) developed a BI. Pre-ECMO Simplified Acute Physiology Score III, pre-ECMO cardiac arrest, VA ECMO and conversion between ECMO modes were identified as predictors of BI. In the multivariable analysis, VA ECMO demonstrated independent risk association. VA ECMO also remained the independent BI predictor in a sub-group analysis excluding patients who did not undergo a head CT scan during ECMO treatment. The incidence of BI in adult ECMO patients may be higher than previously believed and is independently associated with VA ECMO mode. Larger prospective trials are warranted to validate these findings and ascertain their clinical significance. [ABSTRACT FROM AUTHOR]

Contou et al ([1]) compare the results from our unit, recently published in I Critical Care Medicine i ([2]), with data obtained from a retrospective multicenter study on septic shock patients with purpura fulminans admitted to any of 55 participating French hospitals during a 17-year period. In total 0.13 patients/participating center per year, and 0.03 patients/center per year supported with ECMO. ECMO Center Karolinska is a unique specialized high-volume ECMO ICU that has offered ECMO support in refractory septic shock patients for more than 2 decades. [Extracted from the article]

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. [ABSTRACT FROM AUTHOR]

The substantial increase in the number of patients receiving extracorporeal membrane oxygenation over the last decade has led to an evolution of indications and an expansion into wider patient groups. One of the unanticipated benefits of the increase in extracorporeal membrane oxygenation has been a change in the understanding of the natural history of many respiratory diseases. Development in technology and materials, reduced extracorporeal membrane oxygenation–specific complications, and improvement of critical care, in general, have facilitated longer extracorporeal membrane oxygenation runs, and the definition of prolonged extracorporeal membrane oxygenation was recently expanded to continuous support for more than 28 days. This survey aimed to describe European ECMO centers' perception and arbitrary definition of prolonged extracorporeal membrane oxygenation, patient management, and futility. Of 94 center responses, 37% regarded 14-21 days, 30% 21-28 days, and 28% >28 days as prolonged treatment. Bridge to recovery (64%) or to transplantation (20%) was the most common causes. Awake, and ambulation while on extracorporeal membrane oxygenation was reported from 34% of the centers. In case of perceived futility, decision to withdraw was taken in 65% of the centers in agreement between profession and family and in 30% by profession only. One-fourth of the centers did not discontinue support. Large differences prevail among European ECMO centers concerning local perception and patient management in prolonged extracorporeal membrane oxygenation. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to assess the neurologic outcome following extracorporeal cardiopulmonary resuscitation (ECPR) in five European centers.Methods: Retrospective database analysis of prospective observational cohorts of patients undergoing ECPR (January 2012-December 2016) was performed. The primary outcome was 3-month favorable neurologic outcome (FO), defined as the cerebral performance categories of 1-2. Survival to ICU discharge and the number of patients undergoing organ donation were secondary outcomes. A subgroup of patients with stringent selection criteria (i.e., age ≤ 65 years, witnessed bystander CPR, no major co-morbidity and ECMO implemented within 1 h from arrest) was also analyzed.Results: A total of 423 patients treated with ECPR were included (median age 57 [48-65] years; male gender 78%); ECPR was initiated for OHCA in 258 (61%) patients. Time from arrest to ECMO implementation was 65 [48-84] min. Eighty patients (19%) had favorable neurological outcome. ICU survival was 24% (n = 102); 23 (5%) non-survivors underwent organ donation procedures. Favorable neurological outcome rate was lower (9% vs. 34%, p < 0.01) in out-of-hospital than in-hospital cardiac arrest and was significantly associated with shorter time from collapse to ECMO. The application of stringent ECPR criteria (n = 105) resulted in 38% of patients with favorable neurologic outcome.Conclusions: ECPR was associated with intact neurological recovery in 19% of unselected cardiac arrest victims, with 38% favorable outcome if stringent selection criteria would have been applied. [ABSTRACT FROM AUTHOR]

The objective of this animal study was to evaluate the hemodynamic performance of a new centrifugal pump for extra-corporeal membrane oxygenation (ECMO) support in neonates.Six healthy swines were supported with veno-venous ECMO with the New Born ECMOLife centrifugal pump (Eurosets, Medolla, Italy) at different flow rates: 0.25, 0.5, 0.6, and 0.8 L/min; three animals were evaluated at low-flows (0.25 and 0.5 L/min) and three at high-flows (0.6 and 0.8 L/min). Each flow was maintained for 4 hours. Blood samples were collected at different time-points. Hematological and biochemical parameters and ECMO parameters [flow, revolutions per minute (RPM), drainage pressure, and the oxygenator pressure drop] were evaluated.The increase of the pump flow from 0.25 to 0.5 L/min or from 0.6 to 0.8 L/min required significantly higher RPM and produced significantly higher pump pressures [from 0.25 to 0.5 L/min: 1470 (1253–1569) versus 2652 (2589–2750) RPM and 40 (26–57) versus 125 (113–139) mmHg, respectively; p < .0001 for both - from 0.60 to 0.8 L/min: 1950 (1901–2271) versus 2428 (2400–2518) RPM and 66 (62–86) versus 106 (101–113) mmHg, respectively; p < .0001 for both]. Median drainage pressure significantly decreased from −18 (−22; −16) mmHg to −55 (−63; −48) mmHg when the pump flow was increased from 0.25 to 0.5 L/min (p < .0001). When pump flow increased from 0.6 to 0.8 L/min, drainage pressure decreased from −32 (−39; −24) mmHg to −50 (−52; −43) mmHg, (p < .0001). Compared to pre-ECMO values, the median levels of lactate dehydrogenase, d-dimer, hematocrit, and platelet count decreased after ECMO start at all flow rates, probably due to hemodilution. Plasma-free hemoglobin, instead, showed a modest increase compared to pre-ECMO values during all experiments at different pump flow rates. However, these changes were not clinically relevant.In this animal study, the “New Born ECMOLife” centrifugal pump showed good hemodynamic performance. Long-term studies are needed to evaluate biocompatibility of this new ECMO pump. [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]

No major study has been performed on the conversion from venovenous (VV) to venoarterial (VA) extracorporeal membrane oxygenation (ECMO) in adults. This single-center retrospective cohort study aimed to investigate the incidence, indication, and outcome in patients who converted from VV to VA ECMO. All adult patients (≥18 years) who commenced VV ECMO at our center between 2005 and 2018 were screened. Of 219 VV ECMO patients, 21% (n = 46) were converted to VA ECMO. The indications for conversion were right ventricular failure (RVF) (65%), cardiogenic shock (26%), and other (9%). In the converted patients, there was a significant increase in Sequential Organ Failure Assessment (SOFA) scores between admission 12 (9–13) and conversion 15 (13–17, p < 0.001). Compared to non-converted patients, converted patients also had a higher mortality rate (62% vs. 16%, p < 0.001) and a lower admission Respiratory Extracorporeal Membrane Oxygenation Survival Prediction (RESP) score (p < 0.001). Outcomes were especially unfavorable in those converted due to RVF. These results indicate that VA ECMO, as opposed to VV ECMO, should be considered as the first mode of choice in patients with respiratory failure and signs of circulatory impairment, especially in those with impaired RV function. For the remaining patients, Pre-admission RESP score, daily echocardiography, and SOFA score trajectories may help in the early identification of those where conversion from VV to VA ECMO is warranted. Multi-centric studies are warranted to validate these findings. [ABSTRACT FROM AUTHOR]

Multiple prognostic scores have been developed for both veno-arterial (VA) and veno-venous (VV) extracorporeal membrane oxygenation (ECMO), mostly in single-center cohorts. The aim of this study was to compare and validate different prediction scores in a large multicenter ECMO-population. Methods: Data from five ECMO centers included 300 patients on VA and 329 on VV ECMO support (March 2008 to November 2016). Different prognostic scores were compared between survivors and non-survivors: APACHE II, SOFA, SAPS II in all patients; SAVE, modified SAVE and MELD-XI in VA ECMO; RESP, PRESET, ROCH and PRESERVE in VV ECMO. Model performance was compared using receiver-operating-curve analysis and assessment of model calibration. Survival was assessed at intensive care unit discharge. Results: The main indication for VA ECMO was cardiogenic shock; overall survival was 51%. ICU survivors had higher Glasgow Coma Scale scores and pH, required cardiopulmonary resuscitation (CPR) less frequently, had lower lactate levels and shorter ventilation time pre-ECMO at baseline. The best discrimination between survivors and non-survivors was observed with the SAPS II score (area under the curve [AUC] of 0.73 (95% CI 0.67–0.78)). The main indication for VV ECMO was pneumonia; overall survival was 60%. Lower PaCO2, higher pH, lower lactate and lesser need for CPR were observed among survivors. The best discrimination between survivors and non-survivors was observed with the PRESET score (AUC 0.66 (95% CI 0.60–0.72)). Conclusion: The prognostic performance of most scores was moderate in ECMO patients. The use of such scores to decide about ECMO implementation in potential candidates should be discouraged. [ABSTRACT FROM AUTHOR]

Mechanical power (MP) represents a useful parameter to describe and quantify the forces applied to the lungs during mechanical ventilation (MV). In this multi-center, prospective, observational study, we analyzed MP variations following MV adjustments after veno-venous extra-corporeal membrane oxygenation (VV ECMO) initiation. We also investigated whether the MV parameters (including MP) in the early phases of VV ECMO run may be related to the intensive care unit (ICU) mortality. Thirty-five patients with severe acute respiratory distress syndrome were prospectively enrolled and analyzed. After VV ECMO initiation, we observed a significant decrease in median MP (32.4 vs. 8.2 J/min, p < 0.001), plateau pressure (27 vs. 21 cmH2O, p = 0.012), driving pressure (11 vs. 8 cmH2O, p = 0.014), respiratory rate (RR, 22 vs. 14 breaths/min, p < 0.001), and tidal volume adjusted to patient ideal body weight (VT/IBW, 5.5 vs. 4.0 mL/kg, p = 0.001) values. During the early phase of ECMO run, RR (17 vs. 13 breaths/min, p = 0.003) was significantly higher, while positive end-expiratory pressure (10 vs. 14 cmH2O, p = 0.048) and VT/IBW (3.0 vs. 4.0 mL/kg, p = 0.028) were lower in ICU non-survivors, when compared to the survivors. The observed decrease in MP after ECMO initiation did not influence ICU outcome. Waiting for large studies assessing the role of these parameters in VV ECMO patients, RR and MP monitoring should not be underrated during ECMO. [ABSTRACT FROM AUTHOR]

Background: Ultra-protective lung ventilation in acute respiratory distress syndrome or early weaning and/or avoidance of mechanical ventilation in decompensated chronic obstructive pulmonary disease may be facilitated by the use of extracorporeal CO2 removal (ECCO2R). We tested the CO2 removal performance of a new ECCO2R (CO2RESET) device in an experimental animal model. Methods: Three healthy pigs were mechanically ventilated and connected to the CO2RESET device (surface area = 1.8 m2, EUROSETS S.r.l., Medolla, Italy). Respiratory settings were adjusted to induce respiratory acidosis with the adjunct of an external source of pure CO2 (target pre membrane lung venous PCO2 (PpreCO2): 80–120 mmHg). The amount of CO2 removed (VCO2, mL/min) by the membrane lung was assessed directly by the ECCO2R device. Results: Before the initiation of ECCO2R, the median PpreCO2 was 102.50 (95.30–118.20) mmHg. Using fixed incremental steps of the sweep gas flow and maintaining a fixed blood flow of 600 mL/min, VCO2 progressively increased from 0 mL/min (gas flow of 0 mL/min) to 170.00 (160.00–200.00) mL/min at a gas flow of 10 L/min. In particular, a high increase of VCO2 was observed increasing the gas flow from 0 to 2 L/min, then, VCO2 tended to progressively achieve a steady-state for higher gas flows. No animal or pump complications were observed. Conclusions: Medium-flow ECCO2R devices with a blood flow of 600 mL/min and a high surface membrane lung (1.8 m2) provided a high VCO2 using moderate sweep gas flows (i.e., >2 L/min) in an experimental swine models with healthy lungs. [ABSTRACT FROM AUTHOR]