Hemodiafiltration maintains a sustained improvement in blood pressure compared to conventional hemodialysis in children-the HDF, heart and height (3H) study

BACKGROUND: Hypertension is prevalent in children on dialysis and associated with cardiovascular disease. We studied the blood pressure (BP) trends and the evolution of BP over 1 year in children on conventional hemodialysis (HD) vs. hemodiafiltration (HDF). METHODS: This is a post hoc analysis of the "3H - HDF-Hearts-Height" dataset, a multicenter, parallel-arm observational study. Seventy-eight children on HD and 55 on HDF who had three 24-h ambulatory BP monitoring (ABPM) measures over 1 year were included. Mean arterial pressure (MAP) was calculated and hypertension defined as 24-h MAP standard deviation score (SDS) ≥95th percentile. RESULTS: Poor agreement between pre-dialysis systolic BP-SDS and 24-h MAP was found (mean difference - 0.6; 95% limits of agreement -4.9-3.8). At baseline, 82% on HD and 44% on HDF were hypertensive, with uncontrolled hypertension in 88% vs. 25% respectively; p < 0.001. At 12 months, children on HDF had consistently lower MAP-SDS compared to those on HD (p < 0.001). Over 1-year follow-up, the HD group had mean MAP-SDS increase of +0.98 (95%CI 0.77-1.20; p < 0.0001), whereas the HDF group had a non-significant increase of +0.15 (95%CI -0.10-0.40; p = 0.23). Significant predictors of MAP-SDS were dialysis modality (β = +0.83 [95%CI +0.51 - +1.15] HD vs. HDF, p < 0.0001) and higher inter-dialytic-weight-gain (IDWG)% (β = 0.13 [95%CI 0.06-0.19]; p = 0.0003). CONCLUSIONS: Children on HD had a significant and sustained increase in BP over 1 year compared to a stable BP in those on HDF, despite an equivalent dialysis dose. Higher IDWG% was associated with higher 24-h MAP-SDS in both groups

Global Variation of Nutritional Status in Children Undergoing Chronic Peritoneal Dialysis : A Longitudinal Study of the International Pediatric Peritoneal Dialysis Network

While children approaching end-stage kidney disease (ESKD) are considered at risk of uremic anorexia and underweight they are also exposed to the global obesity epidemic. We sought to investigate the variation of nutritional status in children undergoing chronic peritoneal dialysis (CPD) around the globe. The distribution and course of body mass index (BMI) standard deviation score over time was examined prospectively in 1001 children and adolescents from 35 countries starting CPD who were followed in the International Pediatric PD Network (IPPN) Registry. The overall prevalence of underweight, and overweight/obesity at start of CPD was 8.9% and 19.7%, respectively. Underweight was most prevalent in South and Southeast Asia (20%), Central Europe (16.7%) and Turkey (15.2%), whereas overweight and obesity were most common in the Middle East (40%) and the US (33%). BMI SDS at PD initiation was associated positively with current eGFR and gastrostomy feeding prior to PD start. Over the course of PD BMI SDS tended to increase on CPD in underweight and normal weight children, whereas it decreased in initially overweight patients. In infancy, mortality risk was amplified by obesity, whereas in older children mortality was markedly increased in association with underweight. Both underweight and overweight are prevalent in pediatric ESKD, with the prevalence varying across the globe. Late dialysis start is associated with underweight, while enteral feeding can lead to obesity. Nutritional abnormalities tend to attenuate with time on dialysis. Mortality risk appears increased with obesity in infants and with underweight in older children.Peer reviewe

B30 : Tore Supra WEST Cooling Water System for ITER-like conditions

International audienceThe WEST project aims at transforming Tore Supra into an X-point divertor tokamak in order to adapt it to a unique relevant facility as test bed for ITER offering the key capability of testing the ITER technology of high flux components in real plasma environment. All equipment of the existing cooling loop B30 cannot ensure the cooling of the W divertor elements under ITER nominal conditions (12 m/s), so a new pressurized water loop must be designed to exhaust all the heat coming from the plasma and transmitted to the in-vessel components. It includes additional piping networks of around 50m3, replacement of the E30 exchanger and add of a P33 pump

Study of the pores inside tungsten coating after thermal cycling for fusion device

15th International Conference on Plasma-Facing Materials and Components for Fusion Applications (PFMC), Aix en Provence, FRANCE, MAY, 2015International audienceIn the next fusion devices, all the plasma facing components will consist of bulk tungsten or tungsten coating on carbon. This paper focuses on the behaviour of tungsten coated on carbon fibre composite designed for the WEST project (Bucalossi et al 2011 Fusion Eng. Des. 86 684-688) under intensive thermal cycling delivered by an electron beam. The use of scanning electron microscope has allowed in particular, the observation of several pore lines inside the coating. These pore lines have different aspects depending on the observed zone according to the localisation of the electron beam, accentuated lines with more numerous enlarged pores in zone exposed to the electron beam. An analogous trend is also observed for JET tungsten-coated samples under similar thermal cycles despite their different properties due to an alternative manufacturing method of the substrate. A systematic and attentive comparison on the coating changes after the application of the electron beam heating is presented. The observed comportments as the formation of the pore lines or the pore shapes are assumed to be inherent to simultaneous diffusion processes. In association with the pore line formation, a migration of the carbon substrate towards the surface is presumed and discussed

The WEST project: validation program for WEST tungsten coated plasma facing components

The W—for tungsten—Environment in Steady-state Tokamak (WEST) project is based on an upgrade of the Tore Supra tokamak from a carbon limiter to an X-point divertor device. A new set of actively cooled tungsten coated plasma facing components will cover a part of the vessel to provide a fully metallic environment. This paper deals with the validation program performed for tungsten coatings (≥15 μm) on a CuCrZr substrate. The first step was dedicated to the qualification under high heat flux tests of the coating on small inertially cooled samples. To study the thermal behavior and the non-uniformity, the second step was dedicated to the validation of the coating on large inertially cooled samples with geometry and shape (540 × 120 mm) representative of the WEST coated components. The last step was dedicated to the optimization of the coating and to the high heat flux tests up to 10.5 MW m−2 on relevant coated actively cooled prototypes. Non-uniformity and thickness of the coating (15 and 30 μm) correspond to specifications. As no delamination was observed, coatings of 15 and 30 μm were qualified with regard to their application on WEST coated components. In order to decrease the risk of coating delamination under thermal loading, it was decided to cover the upper divertor and baffle targets with the thinnest coating option of 15 μm