Proposal for a quantitative description of blood spiral flow in medical devices.
The association between specific blood flow patterns and blood behaviour through medical devices suggests that a Lagrangian study may be a useful instrument for the evaluation of the thrombogenic and/or hemolytic potential of certain devices' geometries and biomaterials. In this study a description of blood particle trajectories in terms of their spiral contents is proposed; such a mathematical description for blood spiral flow, computed along several pathlines, is tested for a quantitative determination of the spiralled motion of blood flow into two three-dimensional numerical models, having different design characteristics, of venous cannula inserted in a vessel. As the influence of vortical flow conditions have been observed to have both beneficial and detrimental influence on blood behaviour in terms of blood-device interaction, of the degradation of its components, and of the efficiency of mass-exchange (in red cells oxygenation and plasma filtration, for example), the herein proposed method for the description of spiral laminar motion may be a helpful instrument to build up a tool to investigate, for example, the existence of correlations between level of spiral flow and geometry (as in the present investigated test case), rather than the effects of blood-surface contact. The results obtained in this test case investigation, confirm the effectiveness of the proposed function for a quantitative analysis of spiral flow in medical devices.
Grigioni
M
M
Laboratory of Biomedical Engineering, Istituto Superiore di Sanità, Rome, Italy. grigioni@iss.it
Daniele
C
C
Morbiducci
U
U
Del Gaudio
C
C
D'Avenio
G
G
Balducci
A
A
Barbaro
V
V
D001783:Blood Flow Velocity / Q000502:physiology; D001790:Blood Physiological Phenomena; D004867:Equipment Design; D004864:Equipment and Supplies; D006801:Humans; D008955:Models, Cardiovascular