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Resume Les principales sources de greffons sont les donneurs decedes en mort encephalique et les donneurs decedes apres arret circulatoire controle. L’optimisation du don d’organes est d’abord quantitative par l’augmentation du nombre de donneurs potentiels en organisant et en soutenant des filieres de prise en charge a l’echelle regionale (standardisation des pratiques, mise en commun des moyens) et en diminuant le taux de refus par la formation des equipes soignantes. L’optimisation du don d’organes est egalement qualitative et passe par : l’utilisation de protocoles dedies de reanimation et de surveillance chez tous les donneurs ; le recours chez le DDME a l’hypothermie moderee, la dopamine et l’hemissucinate d’hydrocortisone en cas de recours a la noradrenaline ; le recours systematique a un reconditionnement par CRN chez le DDAC ; l’utilisation d’une perfusion ex vivo hypothermique pour les organes issus de DDME a criteres elargis et DDAC. La conservation est un temps de reparation et de qualification des greffons. Une meilleure connaissance des mecanismes lesionnels chez les donneurs permet de proposer des algorithmes de prise en charge personnalisee des greffons.

Contains fulltext : 238746.pdf (Publisher’s version ) (Closed access) Recent biomarker innovations hold potential for transforming diagnosis, prognostic modeling, and precision therapeutic targeting of traumatic brain injury (TBI). However, many biomarkers, including brain imaging, genomics, and proteomics, involve vast quantities of high-throughput and high-content data. Management, curation, analysis, and evidence synthesis of these data are not trivial tasks. In this review, we discuss data management concepts and statistical and data sharing strategies when dealing with biomarker data in the context of TBI research. We propose that application of biomarkers involves three distinct steps-discovery, evaluation, and evidence synthesis. First, complex/big data has to be reduced to useful data elements at the stage of biomarker discovery. Second, inferential statistical approaches must be applied to these biomarker data elements for assessment of biomarker clinical utility and validity. Last, synthesis of relevant research is required to support practice guidelines and enable health decisions informed by the highest quality, up-to-date evidence available. We focus our discussion around recent experiences from the International Traumatic Brain Injury Research (InTBIR) initiative, with a specific focus on four major clinical projects (Transforming Research and Clinical Knowledge in TBI, Collaborative European NeuroTrauma Effectiveness Research in TBI, Collaborative Research on Acute Traumatic Brain Injury in Intensive Care Medicine in Europe, and Approaches and Decisions in Acute Pediatric TBI Trial), which are currently enrolling subjects in North America and Europe. We discuss common data elements, data collection efforts, data-sharing opportunities, and challenges, as well as examine the statistical techniques required to realize successful adoption and use of biomarkers in the clinic as a foundation for precision medicine in TBI.

IntroductionExpanded-criteria donors (ECDs) are used to reduce the shortage of kidneys for transplantation. However, kidneys from ECDs are associated with an increased risk of delayed graft function (DGF), a risk factor for allograft loss and mortality. HYPOREME will be a multicentre randomised controlled trial (RCT) comparing targeted hypothermia to normothermia in ECDs, in a country where the use of machine perfusion for organ storage is the standard of care. We hypothesise that hypothermia will decrease the incidence of DGF.Methods and analysisHYPOREME is a multicentre RCT comparing the effect on kidney function in recipients of targeted hypothermia (34°C–35°C) and normothermia (36.5°C–37.5°C) in the ECDs. The temperature intervention starts from randomisation and is maintained until aortic clamping in the operating room. We aim to enrol 289 ECDs in order to analyse the kidney function of 516 recipients in the 53 participating centres. The primary outcome is the occurrence of DGF in kidney recipients, defined as a requirement for renal replacement therapy within 7 days after transplantation (not counting a single session for hyperkalemia during the first 24 hours). Secondary outcomes include the proportion of patients with individual organs transplanted in each group; the number of organs transplanted from each ECD and the vital status and kidney function of the recipients 7 days, 28 days, 3 months and 1 year after transplantation. An interim analysis is planned after the enrolment of 258 kidney recipients.Ethics and disseminationThe trial was approved by the ethics committee of the French Intensive Care Society (CE-SRLF-16-07) on 26 April 2016 and by the competent French authorities on 20 April 2016 (Comité de Protection des Personnes-TOURS-Région Centre-Ouest 1, registration #2016-S3). Findings will be published in peer-reviewed journals and presented during national and international scientific meetings.Trial registration numberNCT03098706.

To understand how tube bending occurs during the quenching by a water jet, an experimental device has been designed to measure heat transfer, tube bending and to visualize the hydrodynamics of the liquid jet during the cooling of a hot steel tube (grade: 42CrMo4, length: 500 mm, diameter: 76 mm, thickness: 6 mm). The bending resulting from the thermal gradients and phase transformations inside the tube is also measured all along its cooling. Knowing the heat transfer at the wall as a function of the wall surface temperature allowed us to compute the time evolution of temperature, phase transformations and deformations using SYSWELD code. This coupled analysis allows us to better understand why bending can occur in industrial processes.

International audience; Objectives: To compare accuracy of a continuous noninvasive cutaneous temperature using zero-heat-flux method to esophageal temperature and arterial temperature.Design: Prospective study.Setting: ICU and NeuroICU, University Hospital.Patients: Fifty-two ICU patients over a 4-month period who required continuous temperature monitoring were included in the study, after informed consent.Interventions: All patients had esophageal temperature probe and a noninvasive cutaneous device to monitor their core temperature continuously. In seven patients who required cardiac output monitoring, continuous iliac arterial temperature was collected. Simultaneous core temperatures were recorded from 1 to 5 days. Comparison to the esophageal temperature, considered as the reference in this study, used the Bland and Altman method with adjustment for multiple measurements per patient.Measurements and Main Results: The esophageal temperature ranged from 33°C to 39.7°C, 61,298 pairs of temperature using zero-heat-flux and esophageal temperature were collected and 1,850 triple of temperature using zero-heat-flux, esophageal temperature, and arterial temperature. Bias and limits of agreement for temperature using zero-heat-flux were 0.19°C ± 0.53°C compared with esophageal temperature with an absolute difference of temperature pairs equal to or lower than 0.5°C of 92.6% (95% CI, 91.9–93.4%) of cases and equal to or lower than 1°C for 99.9% (95% CI, 99.7–100.0%) of cases. Compared with arterial temperature, bias and limits of agreement were –0.00°C ± 0.36°C with an absolute difference of temperature pairs equal to or lower than 0.5°C of 99.8% (95% CI, 95.3–100%) of cases. All absolute difference of temperature pairs between temperature using zero-heat-flux and arterial temperature and between arterial temperature and esophageal temperature were equal to or lower than 1°C. No local or systemic serious complication was observed.Conclusions: These results suggest a comparable reliability of the cutaneous sensor using the zero-heat-flux method compared with esophageal or iliac arterial temperatures measurements.

IF=2.647; International audience; The present communication reports the main findings of an investigation that has been conducted in order to examine the ductility of both the AISI 4130 and 52100 steel grades, in a wide range of temperatures, spanning from room temperature up to 1250 °C, deformed in tension at strain rates of approximately 0.005 s−1. The ductility of the investigated alloys has been determined employing two different methodologies. The first one is based on the classical definition of this property, as determined from the reduction in the cross sectional area of the tensile specimen after fracture. The second method, which is proposed in this work, is based on the measurement of the energy under the engineering stress-strain curve and the decomposition of the total deformation energy into the uniform plastic and non-uniform or fracture energy components. Complementary axisymmetric compression tests have also been carried out in the temperature range of 600 °Cto 900 °C, in order to determine the strain related to the onset of dynamic recrystallization (DRX) at temperatures above 800 °C, as well as the strain corresponding to the occurrence of necking at these temperatures. The ductility values determined from both methods are observed to increase from approximately 10–80% when the testing temperature increases from room temperature to 1200 °C. Both measurements are also observed to agree up to temperatures of about 600 °C. Also, it has been determined that above this temperature, the ductility values derived from the energy criterion are somewhat higher than those computed from the reduction in the cross section area of the specimens. It has been shown that the onset of DRX gives rise to an improvement in the ductility of both steels, which is also related to a significant increase in the strain for the beginning of necking. The advantage of the energy criterion, in comparison with that based on the area reduction after fracture, is discussed.

16th ESAFORM Conference on Material Forming (ESAFORM 2013), Univ Aveiro, Aveiro, PORTUGAL, APR 22-24, 2013; International audience; Cooling from impinging jet is nearly compulsory in steel industry processing especially in Run Out Table processing and steel tubes production because of the high heat transfer rates provided by the boiling of the subcooled water jet. As far as metallurgical phase transformations, residual stresses and deformations in the workpiece are concerned, the temperature drop during cooling must be perfectly controlled thanks to a fully understanding of the heat transfer mechanisms. In a previous study [1] the effect of surface to jet velocity ratio on heat transfer has been characterized and it has been shown that this parameter has a significant influence on shoulder of flux collapse. In order to understand the effect of more industrial quench process parameters, an innovative experimental quenching device has been designed and built. It allowed us to make heat transfer measurements at the surface of a hot nickel cylinder impinged by a subcooled water jet, according to several angles of impact and three jet directions against gravity. The results clearly highlight an effect of these two parameters on the heat transfer mechanisms at the surface of the tube. These results allow a better understanding of the origins of temperature heterogeneities inside the tube during the quench.

International audience; Cooling from impinging jet is nearly compulsory in steel industry processing especially in Run Out Table processing and steel tube production because of the high heat transfer provided by the boiling of the subcooled water jet. As far as metallurgical phase transformations, residual stresses and deformations in the workpiece are concerned, the temperature drop during cooling must be controlled thanks to a full understanding of the heat transfer mechanisms. One of the main characteristic using jet impingement is that the transition boiling regime may exist for very high superheat and thus the Leidenfrost temperature is higher than in pool boiling; consequently, boiling curves generally have a particular shape in the transition boiling regime which is usually called “shoulder of flux”. In this study, an innovative experimental quenching device has been used for analyzing the effect of the wall velocity of the surface to be cooled on the boiling curves (i.e. heat transfer) and we especially point out that the “shoulder of flux” (i.e. transition boiling regime) is strongly dependent on the surface to jet velocity ratio (r*). We found that a very small increase of the wall velocity has a high influence on shoulder of flux collapse.

Intestinal wall motions are not easily studied and are frequently deduced from manometric and electromyographic measurements. This study aimed to establish a method of wall movement analysis based on an automatic technique of image processing. Segments of rat jejunum were fixed in an organ bath under isometric conditions. A real-time edge-detection algorithm was used to find the contours of the intestine using video imaging. After the measurement, a mapping of intestinal wall movements was performed based on diameter variations. In the 260 experiments without stimulation, intestinal wall activity was always detected. Propagated activity was found in 40% of the experiments and periodic wall motion in 60%, with 0.5-Hz activity found more frequently (41%) than 0.24-Hz activity (19%). These cyclic activities, related to intestinal slow waves, had their amplitude decreased by acetylcholine and were modified by vapreotide. Analysis of a propagated wave after cholinergic stimulation showed that it is characterized by an increase of the diameter of the intestine followed by a decrease. Moreover, this methodology allows analysis of the initiation of a propagated wave.

Background Respiratory rate should be monitored continuously in the post-anaesthesia care unit (PACU) to avoid any delay in the detection of respiratory depression. Capnometry is the standard of care but in extubated patients requires a nasal cannula or a face mask that may be poorly tolerated or can be dislodged, leading to errors in data acquisition and false alarms. The value of a new non-invasive acoustic monitor in this setting has not been fully investigated. Methods Adult patients admitted to the PACU after general anaesthesia were included. After tracheal extubation, an adhesive sensor with an integrated acoustic transducer (RRa™) was placed on the patient's throat and connected to its monitor while the patient breathed through a face mask with a carbon dioxide sampling port (Capnomask™) connected to a capnometer. Both the acoustic monitor and the capnometer were connected to a computer to record one pair of data per second for up to 60 min. Results Fifty-two patients, mean (range) age 54 (22–84) yr and BMI 26 (19–39) kg m−2, were studied. Compared with capnometry, the bias and limits of agreement of the acoustic method were 0 (−1.4–1.4) bpm. The acoustic sensor was well tolerated while the face mask was removed by eight patients, leading to study discontinuation in two patients. Conclusions In extubated patients, continuous assessment of respiration rate with an acoustic monitor correlated well with capnometry.

Introduction La temperature centrale (Tc), presente dans les organes, fait reference car non influencee par la temperature exterieure ou la vasoconstriction cutanee. Elle fait partie du monitorage des patients en reanimation, notamment en cas d’hypothermie therapeutique ou chez les cerebro-leses pour la prevention des ACSOS [1] . Les techniques utilisees a ce jour sont invasives, discontinues ou peu fiables [2] . Un dispositif recent non invasif, 3MaSpotOna(NI), permet une mesure continue de la Tc, cerebrale, par voie transcutanee par la methode du « zero-heat flux » (ZHF) [3] . L’objectif de cette etude prospective, de soins courants (CPP ouest III), a ete d’evaluer la performance de la mesure de la Tc par le ZHF (Tzhf) comparee a la temperature œsophagienne (Toes) et la temperature invasive, sanguine, mesuree par PiCCO (Tsg), comme methodes de reference. Patients et methodes Du 2 aout au 20 novembre 2014, 52 adultes hospitalises en reanimation, monitores en continu par sonde thermique œsophagienne (SO) et NI ont ete inclus ; 7 beneficiaient egalement d’un monitorage par PiCCO recueillant la Tsg. Les donnees ont ete recueillies, pendant un a cinq jours, manuellement chaque heure ou automatiquement toutes les 5 minutes. Les donnees quantitatives ont ete exprimees en mediane et 25–75 e percentiles. La comparaison des Tc entre Tzhf et Toes et entre Tzhf et Tsg a ete realisee selon la methode de Bland et Altman avec ajustement pour mesures multiples pour obtenir les biais et les limites d’agrement (LA). Une analyse multivariee a recherche les facteurs pouvant influer la precision de la mesure entre Tzhf et Toes (curarisation[C], hemodynamique instable [HI], refroidissement actif [RA]). Resultats Les patients, âges de 57 [51–60] ans, sex-ratio (homme/femme) : 1,08, IGSII de 55 [46–60], etaient majoritairement des cerebro-leses (80 % dont 10 % d’ACR) ou hospitalises pour sepsis (10 %) ; 31 298 paires de mesures de Tc (Tzhf, Toes) et 1850 triplets de mesures (Tzh, Toes, Tsg) ont ete analysees. Les valeurs de Toes ont ete comprises entre 33 et 40 °C. Les biais et LA pour le Tzhf sont de −0,19 ± 0,53 °C comparees a Toes et de −0,04 ± 0,35 °C comparees a Tsg. Les facteurs influencant la precision (difference ≥ 0,3 °C par rapport a Toes) de la mesure de Tzhf sont l’HI [OR : 1,19(1,14–1,23)], la C [OR : 2,57(IC95 % : 2,43–2,72)] et le RA [OR : 1,66(IC95 % : 1,58–1,75)]. On retrouve une dermabrasion, sans sequelle, sous le capteur chez 5 patients avec pansement de tete sur 17. Aucune allergie n’est survenue. Discussion Ces resultats suggerent une bonne concordance entre Tzhf et Toes, ainsi que Tsg. La mesure de Tc transcutanee permet de s’affranchir du mauvais positionnement ou deplacement de la SO et d’acceder a la T° cerebrale non invasive, trouvant ainsi son indication chez les cerebro-leses ou dans l’ACR dans le controle thermique.