Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
FLOW ANALYSIS IN A FLEXIBLE ARTERIOVENOUS FISTULA MODEL
Submission Author:
Sabrina Machado Santos , RN , Brazil
Co-Authors:
Sabrina Machado Santos, Jonhattan Ferreira Rangel, Willyam Brito de Almeida Santos, Lucas Penha, Kleiber Lima de Bessa
Presenter: Sabrina Machado Santos
doi://10.26678/ABCM.COBEM2023.COB2023-1012
Abstract
The arteriovenous fistula (AVF) is recognized as the best vascular access for patients with chronic renal failure. It is created by surgically connecting an artery and a vein. One of the common complications after its creation is the reduction of blood flow distally due to arterial blood diversion towards the AVF, known as steal syndrome or hand ischemia. This study aims to analyze the pressure field in a flexible AVF model based on data from a real patient under normal flow conditions and with steal syndrome. A flexible AVF model was manufactured using 3D printing mold injection for conducting the research. The experimental data were collected from pressure transducers at 7 access points in the AVF, and a flow sensor located in the inlet pipe before the artery was used for flow measurement. Two flow regimes were analyzed: without steal syndrome and with steal syndrome (thirty percent of the total flow in the anastomosis coming from the distal artery). The results showed that the pressure exhibited a similar behavior in both cases. The pressure was highest at the inlet and decreased until point 3 (anastomosis). At point 4, the pressure increased compared to the previous point and then decreased again until the final measurement point. For the case without steal syndrome, the inlet and outlet pressures were 3.99 kPa and 0.34 kPa, respectively, and the flow measured at the AVF inlet was 2113.3 ml/min ± 89.66 ml/min. In the case with steal syndrome, the inlet pressure was 3.44 kPa, the outlet pressure was 0.30 kPa, and the flow was 1474.5 ml/min ± 56.53 ml/min. It was observed that the pressure differential in the system for the case with steal syndrome was 3.15 kPa, while for the case without steal syndrome, it was 3.66 kPa. These results indicate a lower average pressure in the system when steal syndrome is present.
Keywords
AVF, pressure, Flow rate, Ischemic steal syndrome, Flexible arteriovenous fistula, pressure drop
