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Abstract Background Peripheral veno-arterial extracorporeal membrane oxygenation (pECMO) has become the first-line device in refractory cardiogenic shock (rCS). Some pECMO complications can preclude any bridging strategies and a peripheral-to-central ECMO (cECMO) switch can be considered as a bridge-to-decision. We conducted this study to appraise the in-hospital survival and the bridging strategies in patients undergoing peripheral-to-central ECMO switch. Methods This retrospective monocenter study included patients admitted to a ECMO-dedicated intensive care unit from February 2006 to January 2023. Patients with rCS requiring pECMO switched to cECMO were included. Patients were not included when the cECMO was the first mechanical circulatory support. Results Eighty patients, with a median [IQR25-75] age of 44 [29–53] years at admission and a female-to-male sex ratio of 0.6 were included in the study. Refractory pulmonary edema was the main switching reason. Thirty patients (38%) were successfully bridged to: heart transplantation (n = 16/80, 20%), recovery (n = 10/80, 12%) and ventricle assist device (VAD, n = 4/30, 5%) while the others died on cECMO (n = 50/80, 62%). The most frequent complications were the need for renal replacement therapy (76%), hemothorax or tamponade (48%), need for surgical revision (34%), mediastinitis (28%), and stroke (28%). The in-hospital and one-year survival rates were 31% and 27% respectively. Myocardial infarction as the cause of the rCS was the only variable independently associated with in-hospital mortality (HR 2.5 [1.3–4.9], p = 0.009). Conclusions The switch from a failing pECMO support to a cECMO as a bridge-to-decision is a possible strategy for a very selected population of young patients with a realistic chance of heart function recovery or heart transplantation. In this setting, cECMO allows patients triage preventing from wasting expensive and limited resources.

Abstract Background Right ventricle impairment (RVI) is common during acute respiratory distress syndrome (ARDS) in adults and children, possibly mediated by the level of transpulmonary pressure (P L). We sought to investigate the impact of the level of P L on ARDS-associated right ventricle impairment (RVI). Methods Adults and children (> 72 h of life) were included in this two centers prospective study if they were ventilated for a new-onset ARDS or pediatric ARDS, without spontaneous breathing and contra-indication to esophageal catheter. Serial measures of static lung, chest wall, and respiratory mechanics were coupled to critical care echocardiography (CCE) for 3 days. Mixed-effect logistic regression models tested the impact of lung stress (ΔP L) along with age, lung injury severity, and carbon dioxide partial pressure, on RVI using two definitions: acute cor pulmonale (ACP), and RV dysfunction (RVD). ACP was defined as a dilated RV with septal dyskinesia; RVD was defined as a composite criterion using tricuspid annular plane systolic excursion, S wave velocity, and fractional area change. Results 46 patients were included (16 children, 30 adults) with 106 CCE (median of 2 CCE/patient). At day one, 19% of adults and 4/7 children > 1 year exhibited ACP, while 59% of adults and 44% of children exhibited RVD. In the entire population, ACP was present on 17/75 (23%) CCE. ACP was associated with an increased lung stress (mean ΔP L of 16.2 ± 6.6 cmH2O in ACP vs 11.3 ± 3.6 cmH2O, adjusted OR of 1.33, CI95% [1.11–1.59], p = 0.002) and being a child. RVD was present in 59/102 (58%) CCE and associated with lung stress. In children > 1 year, PEEP was significantly lower in case of ACP (9.3 [8.6; 10.0] cmH2O in ACP vs 15.0 [11.9; 16.3] cmH2O, p = 0.03). Conclusion Lung stress was associated with RVI in adults and children with ARDS, children being particularly susceptible to RVI. Trial registration Clinical trials identifier: NCT0418467.

Abstract Background The optimal timing of weaning from venovenous extracorporeal membrane oxygenation (VV ECMO) and its modalities have been rarely studied. Methods Retrospective, multicenter cohort study over 7 years in two tertiary ICUs, high-volume ECMO centers in France and Italy. Patients with ARDS on ECMO and successfully weaned from VV ECMO were classified based on their mechanical ventilation modality during the sweep gas-off trial (SGOT) with either controlled mechanical ventilation or spontaneous breathing (i.e. pressure support ventilation). The primary endpoint was the time to successful weaning from mechanical ventilation within 90 days post-ECMO weaning. Results 292 adult patients with severe ARDS were weaned from controlled ventilation, and 101 were on spontaneous breathing during SGOT. The 90-day probability of successful weaning from mechanical ventilation was not significantly different between the two groups (sHR [95% CI], 1.23 [0.84–1.82]). ECMO-related complications were not statistically different between patients receiving these two mechanical ventilation strategies. After adjusting for covariates, older age, higher pre-ECMO sequential organ failure assessment score, pneumothorax, ventilator-associated pneumonia, and renal replacement therapy, but not mechanical ventilation modalities during SGOT, were independently associated with a lower probability of successful weaning from mechanical ventilation after ECMO weaning. Conclusions Time to successful weaning from mechanical ventilation within 90 days post-ECMO was not associated with the mechanical ventilation strategy used during SGOT. Further research is needed to assess the optimal ventilation strategy during weaning off VV ECMO and its impact on short- and long-term outcomes.

This article examines supervisory practices in vocational education and training teaching internships within a blended-learning system. Using a multiple-case study of five triads made up of a university supervisor, a cooperative teacher from the workplace and a student teacher, practices were analysed through the lens of supervisory functions: support, mediation between theory and practice, collaboration, evaluation and internship management. Findings show that support and evaluation practices are dominant within triads. The management function is characterized by practices surrounding the selection and use of digital tools to supervise student teachers in a blended-learning system. The collaboration function appears to be inconsistent from one triad to another, while the mediation between theory and practice function plays a limited role in the practices of all supervisors, despite being identified as one of their main responsibilities.

Abstract Background Coronavirus disease 2019 (COVID-19)-related acute respiratory distress syndrome (ARDS) is associated with high mortality. Extracorporeal membrane oxygenation (ECMO) has been proposed in this setting, but optimal criteria to select target patients remain unknown. Our hypothesis is that evaluation of right ventricular (RV) function could be helpful. The aims of our study were to report the incidence and outcomes of patients eligible for ECMO according to EOLIA criteria, and to identify a subgroup of patients with RV injury, which could be a target for ECMO. Methods Retrospective observational study involving 3 French intensive care units (ICUs) of teaching hospitals. Patients with confirmed SARS-CoV-2 infection between March 2020 and March 2021, presenting ARDS and with available echocardiography, were included. Patients were classified in three groups according to whether or not they met the EOLIA criteria and the presence of RV injury (RVI) (“EOLIA −”, “EOLIA + RVI −” and “EOLIA + RVI + ”). RVI was defined by the association of RV to left ventricular end-diastolic area ratio > 0.8 and paradoxical septal motion. Kaplan–Meier survival curves were used to analyze outcome as well as a Cox model for 90 day mortality. Results 915 patients were hospitalized for COVID-19, 418 of them with ARDS. A total of 283 patients with available echocardiography were included. Eighteen (6.3%) patients received ECMO. After exclusion of these patients, 107 (40.5%) were classified as EOLIA −, 126 (47.5%) as EOLIA + RVI −, and 32 (12%) as EOLIA + RVI + . Ninety-day mortality was 21% in the EOLIA-group, 44% in the EOLIA + RVI-group, and 66% in the EOLIA + RVI + group (p

Abstract Background Fulminant myocarditis is a rare and severe disease whose definite and etiological diagnoses rely on pathological examination. Albeit, myocardial biopsy can be associated with significant morbidity and mortality, its therapeutic consequences are unclear. We conducted a study to determine the diagnostic yield, the safety and the therapeutic consequences of myocardial biopsy in patients with fulminant clinically suspected myocarditis unweanable from mechanical circulatory support (MCS). Methods Monocenter, retrospective, observational cohort study in a 26-bed French tertiary ICU between January 2002 and February 2019. Inclusion of all fulminant clinically suspected myocarditis patients undergoing in-ICU myocardial biopsy while being on MCS. The primary endpoint was the proportion of patients classified as definite myocarditis using Bonaca criteria before and after including myocardial biopsy results. Results Forty-seven patients (median age 41 [30–47], female 53%) were included: 55% died before hospital discharge, 34% could be bridged-to-recovery and 15% bridged-to-transplant. Myocardial biopsy was endomyocardial or surgical in 36% and 64% cases respectively. Tamponade requiring emergency pericardiocentesis occurred in 29% patients after endomyocardial biopsy. After adding the biopsy results in the Bonaca classification algorithm the percentage of definite myocarditis raised from 13 to 55% (p

The review focuses on the mechanism of ventricular interdependence, a frequently encountered phenomena, especially in critically ill patients. It is explained by the anatomy of the heart, with two ventricles sharing a common wall, the septum, and nested in an acutely inextensible envelope, the pericardium. In pathological situation, it results in abnormal movements of the interventricular septum driven by respiration, leading to abnormal filling of one or the other ventricle. Ventricular interdependence has several clinical applications and explains some situations of hemodynamic impairment, especially in situations of cardiac tamponade, severe acute asthma, right ventricular (RV) overload, or more simply, in case of positive pressure ventilation with underlying acute pulmonary hypertension. Ventricular interdependence can be monitored with pulmonary arterial catheter or echocardiography. Knowledge of this phenomena has very concrete clinical applications in the management of filling or in the prevention or treatment of RV overload.

Abstract Background Prone positioning (PP) reduces mortality of patients with acute respiratory distress syndrome (ARDS). The potential benefit of prone positioning maneuvers during venovenous extracorporeal membrane oxygenation (ECMO) is unknown. The aim of this study was to evaluate the association between the use of prone positioning during extracorporeal support and ICU mortality in a pooled population of patients from previous European cohort studies. Methods We performed a pooled individual patient data analysis of European cohort studies which compared patients treated with prone positioning during ECMO (Prone group) to “conventional” ECMO management (Supine group) in patients with severe ARDS. Results 889 patients from five studies were included. Unadjusted ICU mortality was 52.8% in the Supine Group and 40.8% in the Prone group. At a Cox multiple regression analysis PP during ECMO was not significantly associated with a reduction of ICU mortality (HR 0.67 95% CI: 0.42–1.06). Propensity score matching identified 227 patients in each group. ICU mortality of the matched samples was 48.0% and 39.6% for patients in the Supine and Prone group, respectively (p = 0.072). Conclusions In a large population of ARDS patients receiving venovenous extracorporeal support, the use of prone positioning during ECMO was not significantly associated with reduced ICU mortality. The impact of this procedure will have to be definitively assessed by prospective randomized controlled trials.

When digital technologies are used to supervise teacher trainees, internship supervisors adjust their practices to enhance their presence within their cohort in order to reduce the isolation felt by those who choose to do their internship locally, when home is in a remote location from their campus or university. In this article, we will share findings about the concept of social presence through a description of practices according to three indicators from the online community of inquiry theoretical model: emotional expression, open communication and group cohesion. From a qualitative methodology, our results attest to the humanistic nature of the remote supervision. During their online interactions with trainees, the internship supervisors interviewed share their feedback about videos and graded work tactfully, bearing in mind the distance that separates them. Despite how difficult it is to show empathy in mediated communication, they try by many means, including video and immediacy, to comfort trainees who may feel alone. They offer them frequent practical support and check in with them at the beginning and throughout the internship. Their support is bolstered by the authenticity of the situations observed in video footage, above and beyond the institutional systems.

Background: Patients admitted after cardiac arrest with non-shockable rhythm frequently experience hemodynamic instability. This study assessed the hemodynamic consequences of TTM in this sub population. Methods: This is a post hoc analysis of the HYPERION trial (NCT01994772), that randomized patients to either hypothermia or normothermia after non-shockable rhythm related cardiac arrest. Patients with no, moderate or severe circulatory failure were identified with cardiovascular Sequential Organ Failure Assessment at randomization. Primary outcome was the number of patients at day 7 with resolution of shock, accounting for the risk of death (competing risk analysis). Secondary endpoint included neurological outcome and death at day-90. Results: 584 patients were included in the analysis: 195 (34%), 46 (8%) and 340 (59%) had no, moderate and severe circulatory failure, respectively. Resolution of circulatory failure at day 7 was more frequently observed in the normothermia group than in the TTM group (60% [95 %CI 54–66] versus 53% [95 %CI 46–60], Gray-test: p = 0.016). The severity of circulatory failure at randomization was associated with its less frequent resolution at day 7 accounting for the risk of death (76 % [62–86] versus 54% [49–59] for patients with moderate versus severe circulatory failure, Gray test, p

La crise historique que nous venons de traverser dans le monde entier avec la pandémie de la COVID-19 n’a fait que souligner avec une acuité plus intense encore que d’habitude que les effets du numérique sur l’éducation et la formation sont multiples. Nous retenons notamment l’importance de la mise en place de dispositifs technopédagogiques de qualité, qu’ils soient présentiels (en classe), distanciels (à la maison ou au travail) ou hybrides (combinant des activités pédagogiques dans un même espace physique et des activités pédagogiques en ligne), afin de favoriser la création de contextes d’apprentissage permettant à toutes les personnes apprenantes, quelles que soient leurs situations, d’être engagées, d’être accompagnées, d’être guidées, d’être soutenues. Mais, comment concevoir la qualité, alors que l’activité pédagogique, soumise à des tensions, est perçue comme étant entrée en « mode dégradé »? Ce numéro thématique propose une réflexion croisée autour des apports, des possibilités et des contraintes qu’impose le numérique en éducation et en formation. Les autrices et auteurs réunis questionnent également la conception et les éléments qui contribuent à la qualité des dispositifs de formations en ligne et hybrides. Ce quatrième numéro de Médiations & médiatisations restitue des analyses, des réflexions ou des expériences vécues dans ces modalités d’enseignement, illustrant à la fois des réorganisations et la nécessité d’un développement professionnel.

Face au caractère polysémique du terme téléprésence, cet article propose diverses définitions du concept et identifie des utilisations de dispositifs numériques en contexte de formation afin d’être « présent à distance ». Issus d’une démarche de recension systématique des écrits, les dispositifs de téléprésence recensés sont : les salles de visioconférence immersives, les robots de téléprésence, la réalité virtuelle et les hologrammes. Cette vue d’ensemble sur la téléprésence permet de mieux établir les paramètres d’un concept qui permet d’aborder la formation à l’ère du numérique se donnant bien souvent en ligne.

Dirigé par Jean-Luc Rinaudo, « La téléprésence en formation » découle de la tenue en 2017 d’un symposium ayant regroupé des chercheuses et chercheurs de quatre différents pays (France, Belgique, Suisse et Canada) lors des rencontres du Réseau international de recherche en éducation et formation (RÉF). Composé de neuf chapitres répartis selon trois thèmes, l’ouvrage repose sur différents travaux de recherche s’intéressant à la téléprésence, et offre ainsi un vaste panorama de ce sujet phare pour la formation en ligne

Les dispositifs technopédagogiques de type visioconférence sont des technologies émergentes de plus en plus utilisées en enseignement supérieur. Certains établissements d’enseignement investissent largement dans leur implantation et dans leur déploiement au service de la formation à distance. Mais qu’en est-il des usages qu’en font les formateurs? Qu’en est-il du rôle des conseillers/ingénieurs pédagogiques dans un tel contexte? Le présent article traite d’une étude réalisée dans le cadre du projet TOPIC (Téléprésence comme OPportunité d’Innovation dans la Conception de formation) tiré d’un travail conjoint entre l’Université de Sherbrooke (Canada) et l’Université Bretagne Loire (France). Il s’agit d’une enquête en ligne réalisée auprès de 174 formateurs des deux universités partenaires pour répondre à la question : « Quels sont les usages actuels, le niveau d’aisance et les attentes des formateurs face aux dispositifs technopédagogiques de type visioconférence? ». L’enquête fait ressortir que les dispositifs de visioconférence sont peu utilisés et que les formateurs sont peu formés à leur utilisation. Malgré tout, une majorité des répondants se dit à l’aise avec leur capacité d’enseigner avec le numérique. En termes de formations, il ressort de l’enquête que les formateurs privilégient des ressources propices à l’autoformation, à un accompagnement personnalisé ou à une combinaison de ressources et d’accompagnement.

Acute respiratory distress syndrome (ARDS) is characterized by protein-rich alveolar edema, reduced lung compliance and severe hypoxemia. Despite some evidence of improvements in mortality over recent decades, ARDS remains a major public health problem with 30% 28-day mortality in recent cohorts. Pulmonary vascular dysfunction is one of the pivot points of the pathophysiology of ARDS, resulting in a certain degree of pulmonary hypertension, higher levels of which are associated with morbidity and mortality. Pulmonary hypertension develops as a result of endothelial dysfunction, pulmonary vascular occlusion, increased vascular tone, extrinsic vessel occlusion, and vascular remodeling. This increase in right ventricular (RV) afterload causes uncoupling between the pulmonary circulation and RV function. Without any contractile reserve, the right ventricle has no adaptive reserve mechanism other than dilatation, which is responsible for left ventricular compression, leading to circulatory failure and worsening of oxygen delivery. This state, also called severe acute cor pulmonale (ACP), is responsible for excess mortality. Strategies designed to protect the pulmonary circulation and the right ventricle in ARDS should be the cornerstones of the care and support of patients with the severest disease, in order to improve prognosis, pending stronger evidence. Acute cor pulmonale is associated with higher driving pressure (≥18 cmH2O), hypercapnia (PaCO2 ≥ 48 mmHg), and hypoxemia (PaO2/FiO2 < 150 mmHg). RV protection should focus on these three preventable factors identified in the last decade. Prone positioning, the setting of positive end-expiratory pressure, and inhaled nitric oxide (INO) can also unload the right ventricle, restore better coupling between the right ventricle and the pulmonary circulation, and correct circulatory failure. When all these strategies are insufficient, extracorporeal membrane oxygenation (ECMO), which improves decarboxylation and oxygenation and enables ultra-protective ventilation by decreasing driving pressure, should be discussed in seeking better control of RV afterload. This review reports the pathophysiology of pulmonary hypertension in ARDS, describes right heart function, and proposes an RV protective approach, ranging from ventilatory settings and prone positioning to INO and selection of patients potentially eligible for veno-venous extracorporeal membrane oxygenation (VV ECMO).

Ce numéro spécial repose sur différentes études liées au portfolio numérique en enseignement supérieur. Ce texte de cadrage propose un survol des visées et des cadres de référence des articles qui y sont réunis, en plus d’établir un éventail de contextes d’implantation du portfolio numérique au Canada et en Europe. Divers enjeux émanant de cette publication sont également identifiés afin de contribuer à la réflexion de ceux qui utilisent cet outil de près ou de loin, ou qui songent à son implantation dans un cours ou un programme de formation. This special issue is based on various studies related to the digital portfolio in higher education. This scoping text provides an overview of the aims and conceptual frameworks of the articles that are brought together, as well as establishing a range of digital portfolio implementation contexts in Canada and Europe. In addition, various issues emanating from this publication are identified to contribute to the reflection of those who use this tool from near or far, or who are thinking about its implementation in a course or a training program.

Lorsque la supervision de stage en enseignement se fait à distance, l’approche collaborative des acteurs du milieu universitaire et de ceux du milieu scolaire nécessite des ajustements, voire de nouvelles façons de faire au service d’un dialogue favorable au développement professionnel des stagiaires. Si cette collaboration relève à la fois de possibilités et de limites à l’égard de la « présence » lors d’une supervision de stage à distance, notre recherche en révèle certaines caractéristiques selon un contexte particulier. L’objet de cette recherche était initialement le sentiment de présence de stagiaires supervisés à distance; la collaboration entre les superviseurs et les acteurs du milieu scolaire à l’aide des technologies de l’information et de la communication (TIC) s’est imposée au cours de l’analyse des données et cet article y est consacré. Selon le cadre de l’apprentissage collaboratif à distance de Henri et Lundgren-Cayrol (2001), nous en viendrons à proposer un collectif d’accompagnement au sein duquel la collaboration comporte des interactions enseignantes, cognitives et sociales dans un environnement en ligne réunissant entre autres le stagiaire, le superviseur et les acteurs du milieu.

Three-dimensionally (3D) nanoarchitectured palladium/nickel (Pd/Ni) catalysts, which were prepared by atomic layer deposition (ALD) on high-aspect-ratio nanoporous alumina templates are investigated with regard to the electrooxidation of formic acid in an acidic medium (0.5 M H2SO4). Both deposition processes, Ni and Pd, with various mass content ratios have been continuously monitored by using a quartz crystal microbalance. The morphology of the Pd/Ni systems has been studied by electron microscopy and shows a homogeneous deposition of granularly structured Pd onto the Ni substrate. X-ray diffraction analysis performed on Ni and NiO substrates revealed an amorphous structure, while the Pd coating crystallized into a fcc lattice with a preferential orientation along the [220]-direction. Surface chemistry analysis by X-ray photoelectron spectroscopy showed both metallic and oxide contributions for the Ni and Pd deposits. Cyclic voltammetry of the Pd/Ni nanocatalysts revealed that the electrooxidation of HCOOH proceeds through the direct dehydrogenation mechanism with the formation of active intermediates. High catalytic activities are measured for low masses of Pd coatings that were generated by a low number of ALD cycles, probably because of the cluster size effect, electronic interactions between Pd and Ni, or diffusion effects.

Guidés par une démarche SoTL (Scholarship of teaching and learning), nous témoignons dans cet article de l’implantation d’une nouvelle plateforme de portfolio numérique au sein de deux programmes universitaires de formation en enseignement. Ces démarches d’innovation curriculaire reposent sur des conceptions pédagogiques liées aux portfolios d’apprentissage et de développement professionnel. À partir des réponses obtenues d’un questionnaire rempli par des étudiants de ces programmes, notre réflexion permet de dégager des avenues de formation ainsi que des questionnements qui font écho à des résultats de recherches sur le portfolio numérique en enseignement supérieur.

The Mn _5 Ge _3 compound, thanks to its room-temperature ferromagnetism, metallic character and ability to epitaxially grow on germanium, acts as a potential candidate for spin injection into group-IV semiconductors. Understanding and controlling Ge overgrowth behaviour on Mn _5 Ge _3 /Ge heterostructures represents a crucial step to realize Ge/Mn _5 Ge _3 /Ge multilayers for numerous spintronic applications. Here, we have combined structural and morphological characterizations with magnetic analyses to study the mechanisms of Ge overgrowth on epitaxial Mn _5 Ge _3 layers in the temperature range of 450–550 °C. It is found that deposited Ge instantly reacts with Mn to form a Mn _5 Ge _3 surface layer, which, acting as a surfactant, continuously floats upwards from the growing surface to a distance larger than 70 nm. New Ge layers are successively formed underneath, allowing such a floating Mn _5 Ge _3 surface layer to be stabilized by epitaxy. These observations can be considered as a typical example in which the stabilization of metastable thin films by epitaxy can overcome thermodynamic equilibrium. We have also investigated the effect of carbon adsorption on the top of the Mn _5 Ge _3 layer prior to Ge deposition to control the Mn:Ge reaction. It is shown that adsorbed carbon effectively reduces the out-diffusion of Mn from Mn _5 Ge _3 , allowing Ge layers to stack up on top of Mn _5 Ge _3 . However, at temperatures of 450–550 °C, carbon may react with Mn to form manganese carbides and the resulting Ge overlayers are found to change their orientation from the (111) plane to the (001) plane, which has a higher surface energy. Finally, a strategy to realize Ge/Mn _5 Ge _3 /Ge multilayers will be addressed.

When a teaching internship takes place abroad or in remote areas, the support offered by the university (or a higher education school) can be done without presence. Increasingly, supervisors of these internships can use a range of ICT to limit problems caused by distance, including the isolation of the learner. From qualitative and quantitative results of an exploratory-descriptive study of comprehensive nature, we identify the key features of a remote internship supervision regarding the creation of a sense of presence. According to different types of presence (teaching, cognitive and social), ICT use, the possibility of a hybrid supervision, collaboration with members in the school community, and ethical issues, these features facilitate the identification of robust actions for creating presence in internship supervision.