Relation between paper filterability and viscosity of normal and abnormal red cell suspensions

Abstract

The filterability of concentrated red cell suspensions as assayed with filter paper is considered to be a measure of the suspension viscosity. In order to investigate how filterability is related to viscosity as determined in a cone and plate rotational viscometer we have studied suspensions of normal and artificially altered red cells with both methods.

For shear rates between 11 and 230 sec⁻¹ a positive correlation was found between apparent viscosity and index of filterability. The correlation was better the higher the shear rates used in viscometry. At high shear rates the common critical variable appears to be red cell deformability. The lower the shear rate, cell-cell-interactions and other factors become more important. Such factors may be of particular significance for red cell behaviour in the microcirculation of which the filter paper represents a possible model.