Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Comparison of Different Mathematical Models for the Evaluation of Hemolytic and Thrombogenic Potentials in Central Venous Access for Hemodialysis
Submission Author:
Matheus Carvalho Barbosa Costa , MG
Co-Authors:
Matheus Carvalho Barbosa Costa, Saulo Gonçalves, Mário Silva, Thabata Lucas, Rudolf Huebner
Presenter: Matheus Carvalho Barbosa Costa
doi://10.26678/ABCM.COBEM2023.COB2023-0715
Abstract
Central Venous Catheter is a form of vascular access to perform the renal clearance procedure of hemodialysis, and is in increasing use worldwide. Despite the catheter has advantages over other forms of vascular access, it has some risks, such as thrombus formation and hemolysis. The increasing thrombus formation causes obstructions in the catheter orifices, thus causing a decrease in the efficiency of the device, as well as increasing the incidence of other secondary adversities, such as thrombosis and pulmonary embolism. Studies indicate that hemolysis and thrombus formation are associated with two physical factors of blood flow: shear stress and time of exposure to these stresses. There are two types of mathematical models that aim to predict thrombus formation and hemolysis, each having its advantages and disadvantages: Lagrangian models and Eulerian model. The present work aims to evaluate different mathematical models to estimate the hemolytic and thrombogenic potentials, and the contribution of the dialysis flow in these variables, in the central venous access for hemodialysis using Computational Fluid Dynamics. The geometry of the central veins was obtained through a Computed Tomography of a healthy, male, 74-year-old patient and was used a catheter MedCOMP/HEMO-CATH model. The simulations were carried out in a transient regime with physiological boundary conditions, using the K-ω SST model to characterize the turbulence, the Carreau Yasuda model for the rheological behavior of the blood and five Lagrangian models and the Eulerian model were implemented to estimate the hemolytic and thrombogenic potentials. In addition, three different dialysis flows were considered: 200, 300 and 400 mL/min. With the simulations, it is expected that the thrombogenic and hemolytic potentials increase, both for the Lagrangian models and for the Eulerian model, due to the increase in the dialysis flow rate. This is expected, since the shear stress increases considerably with the increase in dialysis flow. In addition, it is expected that the six analyzed models present different values, since the integrations along the trajectory lines are different for each model. With the present work, it is possible to observe that numerical studies are a viable alternative to study the possibility of improving hemodialysis procedures, in order to reduce the complications that imply the removal and replacement of catheters, to guarantee a process of clinical practice more efficient and avoid risks related to the propagation of secondary adversities.
Keywords
hemodialysis, central venous catheter, Hemolytic Potential, Thrombogenic potential, Computational Fluid Dynamics, Eulerian model, Lagrangian model
