Affiliations: [a] Department of Engineering and Maintenance, Kaohsiung Veteran General Hospital, Kaohsiung, Taiwan | [b] Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan | [c] Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, Taiwan
Correspondence:
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Corresponding author: Cheng Dann Kan, Department of Surgery, National Cheng Kung University Hospotal, Taiwan, Taiwan. E-mail:lynnchen.k@gmail.com
Abstract: Vascular access dysfunction commonly occurs in
hemodialysis patients. Regularly monitoring and evaluating the vascular
access condition is an important issue for these diseased patients. The
objective of this study was to identify acoustic parameters and hemodynamics
that related to changes in the stenosis of vascular access. In-vitro
experimental circulation system offered pulsatile and physiological
condition to simulate the arteriovenouse access in hemodialysis patient. We
created the environments of various degrees of stenosis (DOS) inside the
arteriovenouse access to simulate the stenotic conditions in patients. And
we also used the computational fluid dynamics (CFD) to simulate the pressure
distribution, primary axial velocity distribution, and secondary flow
distribution in the same various DOS and boundary condition. There are two
findings, one is recorded the bruit which caused by the fluctuation of fluid
in different severe stenosis, the other is described the correlation between
bruit and hemodynamic parameters. Experimental results show the time
constants have linear regression with a positive correlation as the degree
of stenosis (DOS) increases. Finally, in contrast to CFD computerized
analysis and acoustic methods, the proposed parameter provides a feasibility
index for evaluating the risk of AVG dysfunction in on-line/real time
analysis.
