[Monitoring of heparinization in cardiac surgery with ACT: accreditation of the point-of-care test in the Bordeaux University Hospital Centre]. / Surveillance de l'héparinisation en chirurgie cardiaque par l'ACT : accréditation de l'analyse en biologie délocalisée au CHU de Bordeaux.

ACT (Activated Clotting Time) is a point of care test (POCT) on whole blood, used to monitor the heparinization of patients in the operating room in cardiac surgery (ExtraCorporeal Circulation ECC) and in interventional cardiology (TAVI, AF ablation). The ACT is concerned both by the ISO 22 870 standard and French regulations regarding POCT. We performed an important work at the Bordeaux CHU on its accreditation, by rationalizing and making the park uniform (11 HemochronTM Signature Elite), standardizing the training and the habilitation of operators in medical units, introducing periodic quality controls, centralizing in the laboratory the management of the devices and reagents and by connecting it to the laboratory's computer system (Middleware, SIL et expert softwares). One year after, we have some positive feedbacks with only a few technical problems and with only few remarks raised during internal audits.

[How to accredit bedside total hemoglobin measurement with the HemoCue® point-of-care device?] / Accréditer la mesure de l'hémoglobine totale au lit du malade sur équipement de biologie délocalisée de type HemoCue®.

HemoCue® point-of care devices are widely used in Bordeaux university hospital center to assess hemoglobin in critical situations, with 45 devices in 13 health units. Based on our experience, we here propose essential steps in order to prepare the accreditation file. We develop risks analysis, mandatory validation method check points, and caregiver professional training. Among the tasks, precise reference quality instructions i.e. instruction for use, maintenance and troubleshooting should be available. We also share reflections to offer solutions to encountered difficulties. The implemented quality management must rely on a solid and involved laboratory organization. A strong caregiver membership also appears to be the key to move forward.

[Point-of-care testing: place of France in the world National survey in healthcare establisments in 2019]. / Examens de biologie médicale délocalisée : place de la France dans le monde Enquête nationale en 2019 dans les établissements de santé.

The point-of-care tests (POCT) are subject to accreditation. A national inventory survey provides a synthesis of knowledge. The survey distributed 31 questions in 2019. 147 responses were received (75% biologists, 49% CHU, 42% CHG). Only 20.41% are accredited ISO22870, the majority for <50% of the medical departments; 70% say they are going there at the end of 2019 or in 2020. The maps are unknown for 32% (EBMD) and 82% (TROD). Visibility is poor with: medical establishment committee (40%), IT department (31%). Connection is necessary for 87-95% depending on the criterion (QC, authorizations, etc.) and 66% of answers highlight that less than 50% of connexion is effective. The major advantage is the delay of the result (62.5%), then the relationship with the health teams (33.3%). The disadvantages: difficulty of the quality approach (45%), cost of tests (34.3%). Human resource requirements are identified for technicians (82%) and biologists (76%). The multiplicity of sites, devices and operators means that it is difficult to set up and maintain. Biology outside the laboratories, under biological responsibility, must meet a rigorous imperative quality approach.

Effect of magnesium on mRNA expression and production of endothelin-1 in DOCA-salt hypertensive rats.

The aim of this study was to investigate whether or not the decrease in blood pressure induced by dietary magnesium supplementation in DOCA-salt hypertensive rats is associated with modifications in expression and tissular production of endothelin-1. DOCA-salt treatment increased blood pressure, induced renal and cardiac hypertrophy, and increased endothelin-1 expression and production in the kidney, heart, and aorta. Mg supplementation for 8 weeks lowered blood pressure in DOCA-salt hypertensive rats and prevented hypertrophies and the increase of endothelin-1 expression and production in the heart, aorta, and kidney. Treatment with a receptor ETA antagonist, ABT-627, was used to clarify the relationship between the lowering effect of Mg supplementation on blood pressure and endothelin-1 production. When DOCA-salt rats were treated with ABT-627 for 8 weeks, Mg supplementation failed to lower blood pressure. In conclusion, these findings suggest that the lowering effect of Mg supplementation on blood pressure requires an inhibitory effect on endothelin-1 activity and/or endothelin-1 production in DOCA-salt hypertensive rats.

Magnesium supplementation and deoxycorticosterone acetate--salt hypertension: effect on arterial mechanical properties and on activity of endothelin-1.

The aim of this study was to show whether the decrease in blood pressure induced by Mg supplementation in deoxycorticosterone acetate - salt (DOCA-salt) hypertensive rats is associated with mechanical modifications of blood vessels and (or) changes in tissular production and (or) vasoconstrictor activity to endothelin-1. DOCA-salt treatment increased blood pressure, media thickness, cross-sectional area, and lumen diameter of carotid arteries. Distensibility and incremental elastic modulus versus stress were not altered in carotid arteries, suggesting that the DOCA-salt vessel wall adapts structurally to preserve its blood pressure buffering capacity. Magnesium supplementation attenuated DOCA-salt hypertension. In comparison with normotensive rats, systolic, mean, and pulse pressures were higher whereas diastolic pressure was not different in Mg-supplemented DOCA-salt rats. Magnesium supplementation did not significantly modify the elastic parameters of carotid arteries. In resistance mesenteric arteries, DOCA-salt hypertension induces an inward hypertrophic remodeling. Magnesium supplementation attenuates wall hypertrophy and increases lumen diameter to the normotensive diameter, suggesting a decrease in peripheral resistance. Magnesium supplementation normalizes the altered vasoconstrictor activity of endothelin-1 in mesenteric arteries and attenuates endothelin-1 overproduction in kidney, left ventricle, and aorta of DOCA-salt rats. These findings suggest that Mg supplementation prevents blood pressure elevation by attenuating peripheral resistance and by decreasing hypertrophic effect of endothelin-1 via inhibition of endothelin-1 production.