Experimental studies on hemodialysis access innovations

Tissue engineered blood vessels and medical devices for hemodialysis vascular access.</table

Experimental studies on hemodialysis access innovations

Tissue engineered blood vessels and medical devices for hemodialysis vascular access.HartstichtingLUMC / Geneeskund

Utilizing the Foreign Body Response to Grow Tissue Engineered Blood Vessels in Vivo

Nephrolog

Arteriovenous conduits for hemodialysis: how to better modulate the pathophysiological vascular response to optimize vascular access durability

Vascular access is the lifeline for patients on hemodialysis. Arteriovenous fistulas (AVFs) are the preferred vascular access, but AVF maturation failure remains a significant clinical problem. Currently, there are no effective therapies available to prevent or treat AVF maturation failure. AVF maturation failure frequently results from venous stenosis at the AVF anastomosis, which is secondary to poor outward vascular remodeling and excessive venous intimal hyperplasia that narrows the AVF lumen. Arteriovenous grafts (AVGs) are the next preferred vascular access when an AVF creation is not possible. AVG failure is primarily the result of venous stenosis at the vein-graft anastomosis, which originates from intimal hyperplasia development. Although there has been advancement in our knowledge of the pathophysiology of AVF maturation and AVG failure, this has not translated into effective therapies for these two important clinical problems. Further work will be required to dissect out the mechanisms of AVF maturation failure and AVG failure to develop more specific therapies. This review highlights the major recent advancements in AVF and AVG biology, reviews major clinical trials, and discusses new areas for future research.Nephrolog

Bolsa familia y la asistencia social en Brasil: de la lucha política a la mercantilización local

El propósito de este artículo es tanto teórico como metodológico: busca contribuir a la reflexión de la sociología acerca de los usos de las políticas sociales, mostrando que el estudio de una determinada "política" como Bolsa Familia requiere un dispositivo de investigación multi-escalar que permita captar los diversos conflictos que atraviesan su concretización, desde su emergencia hasta su despliegue en el territorio. En este sentido, a modo de ejercicio, se interroga la trayectoria de implementación del programa Bolsa Familia en dos momentos distintos en torno a su tecnología política "por arriba" y "por abajo": como dispositivo de gobierno (Foucault, 1976), emblemático durante el período de "Lula", y como dispositivo de gestión del territorio y de las poblaciones a través de la externalización o tercerización asistencial. En uno y otro momento, lo social adquiere valor de "mercadería política" a distintos niveles. Mostraremos cómo se produce en ellos el despliegue de la política de asistencia social: a nivel de Estado y lo público, y a nivel del territorio y la acción privada y no gubernamental. A nivel de su concretización, mostraremos, a partir de un caso de estudio en São Paulo, la importancia de seguir la cadena de producción de la política. Destacaremos, así, algunos elementos centrales de lo que podría ser llamado un modelo "PSDB", vigente en esa ciudad, como veremos al final

A Proof-of-Principle Study of the Design and Optimization of a Novel Fluid-Driven Automated Retracting Needle System

The cannulation of blood vessels is one of the most basic and essential interventions in medical practice. A common adverse event of this procedure is miscannulation with infiltration of the second part of the vessel wall, often resulting in a perivascular hematoma. In hemodialysis patients, surgically created arteriovenous conduits are cannulated 3-4 times per week to provide sufficient blood supply to the hemodialysis machine. However, the high blood flow and pressure in these vascular access sites increase the risk of complications upon miscannulation. A novel needle system that allows for rapid automatic retraction of the needle in response to contact with blood after positioning the cannula in the blood vessel was developed to reduce the risk of miscannulation. The device can easily be incorporated into existing needle designs. The mechanical functionality of the device was validated by testing prototypes in an ex vivo system. Optimization of the needle system was performed to enhance response time and piston shape. A final prototype design was manufactured and validated. The optimal membrane composition and piston shape were determined, which resulted in a needle response time of 40 ms upon contact with fluid at a pressure of 100 mmHg (arterial pressure). Here, we have successfully designed, mechanically validated, and tested a novel automated rapid needle retraction system that allows incorporation into existing needle systems. This device could notably decrease the difficulty of vessel cannulation and the prevalence of hematoma formation.Nephrolog

CHRONIC KIDNEY DISEASE DOES NOT IMPACT THE MORPHOLOGY AND CELLULAR COMPOSITION OF IN VIVO TISSUE ENGINEERED BLOOD VESSELS IN RATS

Vascular nephrolog