On the effect of dynamic flow conditions on blood microstructure investigated with optical shearing microscopy and rheometry

Efstathios Kaliviotis1, M. Yianneskis1
1Department of Mechanical Engineering, Experimental and Computational Laboratory for the Analysis of Turbulence, King's College London, London, UK

Tóm tắt

Red blood cell (RBC) aggregation affects significantly the flow of blood at low shear rates. Increased RBC aggregation is associated with various pathological conditions; hence an accurate quantification and better understanding of the phenomenon is important. The present study aims to improve understanding of the effect of dynamic flow conditions on aggregate formation; whole blood samples from healthy volunteers, adjusted at 0.45 haematocrit were tested in different flow conditions with a plate-plate optical shearing system, image analysis, and a double-walled Couette rheometric cell. Results are presented in terms of aggregation index Aa, aggregate size index As and number of aggregates, which are shown to vary with shear rate γ and with different shear rate variations with time γ. The aggregation index Aa was observed to increase as the shear rate decreased between 10 and 3 s−1. Above 10 s−1, Aa was found to have a minimum value indicating minimal aggregation while, at approximately 3 s−1, Aa reaches a maximum. The aggregation size index As, the number of aggregates, and the blood viscosity were found to vary considerably when the same sample was examined over the same shear rate range, but for different variations of shear rate with time, γ.

Từ khóa


Tài liệu tham khảo

Rampling M. W., 2004, Biorheology, 41, 91

10.1146/annurev.fluid.37.042604.133933

10.1016/S0006-3495(00)76791-9

Lowe G. D.O., 1989, Clin. Blood Rheol., 1, 11

Rampling M. W., 1989, Clin. Blood Rheol., 1, 45

10.1002/1522-2683(200207)23:13<2103::AID-ELPS2103>3.0.CO;2-O

10.1016/S0927-7757(99)00345-3

10.1016/S0006-3495(72)86156-3

10.1016/S0006-355X(97)00002-4

10.1046/j.1525-1594.1999.06408.x

10.1136/jcp.46.3.198

Baskurt O., 1998, Clin. Hemorheol. Microcirculation, 19, 307

Marton Z., 2001, Clin. Hemorheol. Microcirculation, 24, 75

Schmid-Schoenbein H., 1983, Clinical Hemorheol., 2, 93

10.1063/1.1832456

10.1152/jappl.1969.26.5.674

10.3233/BIR-1975-12501

10.1152/ajpheart.1983.245.2.H252

10.1152/ajpheart.00690.2004

10.1590/S1516-14392002000300008

10.1016/j.thromres.2004.04.009

1998, Biotechnology - laboratories for research, development and analysis - containment levels of microbiology laboratories, areas of risk, localities and physical safety requirements

10.1079/BJN19860136

Kaliviotis E., Jackson S. H. D., Ouldred E., Yianneskis M. Investigation of the fluid mechanics of the red blood cell aggregation in blood flow. In Proceedings of the First Meeting of the Physiological Flow Network, Nottingham, UK, 11–12 April 2005, pp. 23–24.

10.1016/S0377-0257(00)00162-2

Snabre P., 1996, J. Phys., Paris, III, 6, 1835

10.1016/0377-0257(94)01282-M

Baskurt O., 2005, Biorheology, 42, 319

10.1126/science.168.3934.977