Thixotropy of Blood and Proneness to Thrombus Formation

Abstract

A study of the viscosity and thixotropy of human blood in the absence of anticoagulants was carried out by means of a rotational cone-in-cone viscometer. The plots of viscosity against the rate of shear on a log-log scale show that the thixotropy of normal blood is pronounced only below 5 sec.^-1; abnormally thixotropic blood was characterized by the critical rates of shear of 30 to 60 sec.^-1. The significance of thixotropy of blood is due to its intimate relationship with the aggregation of red cells. It is suggested that it may be also related to the proneness of thrombus formation.