Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
ANALYSIS OF PRESSURE DROP IN ARTERIOVENOUS FISTULA WITH VARIATION OF THE ANGLE OF ANASTOMOSE - in vitro study
Submission Author:
Willyam Brito de Almeida Santos , RN
Co-Authors:
Willyam Brito de Almeida Santos, Jonhattan Ferreira Rangel, Thercio Costa, Kleiber Lima de Bessa
Presenter: Willyam Brito de Almeida Santos
doi://10.26678/ABCM.COBEM2021.COB2021-0560
Abstract
The Arteriovenous Fistula (AVF) is a connection between an artery and a vein, made by a vascular surgeon for vascular access (AV) in people undergoing hemodialysis (HD). The construction of the AVF causes non-physiological conditions of blood flow, as a result of this it generates disturbances in the flow in the connection region, anastomosis. These disturbances such as recirculation zones, separation points and stagnation points are associated with the development of pathologies that cause stenosis, compromising or even canceling the use of the AVF as a VA. The Angle of Anastomosis (AA) is one of the geometric parameters that influence the intensity of perturbations in the anastomosis. Using the Fused Deposition Modeling (FDM) technique, in vitro models of the AVF were manufactured by 3D printing with 30°, 90° and 150° AA. An experimental workbench was used to provide the pulsatile flow. Pressures at the inlet and outlet of the AVF were collected using MPU5050DP pressure transducers. The results show that the upstream pressure decreases with the increase of AA and the downstream pressure increases, consequently the pressure differential decreases with the increase of AA, from 12 kPa at 30° AA to 3.1 kPa at 150 AA °. Therefore, the energy dissipated during the flow decreases in the anastomosis with the increase in AA. From the results obtained, it can be concluded that the AA influences the pressure between the region upstream and downstream of the anastomosis. The smaller the AA, the greater the pressure difference and the greater the energy dissipated in the anastomosis. In this context, it was estimated that the 150 ° AA is more favorable for the construction of the AVF because they present less changes in the system pressure, less energy dissipated in the anastomosis and, consequently, lower levels of disturbances in the flow.
Keywords
Arteriovenous Fistula, pressure drop, Angle of Anastomose
