Computational fluid dynamics analysis of venous air trap chamber geometry for reduction of blood coagulation

(Introduction) In blood purification therapy, contact between foreign particles and the blood can activate blood coagulation factors or platelets. Consideration of the effects of differences in chamber geometry has generally been absent from reports on standardization of hemodialysis circuits, even though blood coagulation tends to occur in the venous air-trap chamber of a hemodialysis circuit because of both exposure of blood to internal air and delay or stagnation of blood flow. We considered that improving the filter and blood inflow design to control eddy formation and pooling and reduce the duration of blood pooling could potentially reduce coagulation in the chamber. In the present study, a theoretical investigation of the effects of chamber design parameters on coagulation was performed using computational fluid dynamics (CFD), and the appropriateness of CFD analysis was evaluated through visualization of the flow using particle image velocimetry (PIV). © 2021, Japan Soc. of Med. Electronics and Biol. Engineering. All rights reserved.