Effects of aggregation on the blood flow velocity field measured by a μPIV based technique

Abstract

The flow of red blood cells is investigated by means of a micro-PIV based technique at physiological hematocrit levels and in the presence of aggregation. The technique developed differs from typical micro-PIV as the RBCs are used as tracer particles and illumination is provided by a simple halogen light source. Changes in the microstructure of blood caused by aggregation were observed to affect the RBC flow characteristics in a narrow-gap plate-plate geometry. At low shear rates, high aggregation caused the RBC motion to become essentially two-dimensional and network formation lead to the flow deviating from the expected radial profile. The accuracy of the micro-PIV technique was shown to be dependent on aggregation, illustrating the need to take aggregation into account in future RBC flow studies.