Abstract: An apparatus for determining the viscosity of fluids, particularly blood plasma, includes an outer housing including a front surface having a groove therein; a disposable capillary tube removably mounted in the groove and including at least one loop, each of the loops having two substantially horizontal branches including an upper branch and a lower branch for flowing the fluid under the influence of gravity through a predetermined path, and a device for measuring the rate of flow of the fluid along the path in one of the horizontal branches. Also disclosed is a flexible disposable capillary tube for the fluid viscosity measuring apparatus.

Abstract: For measuring the deformation capacity of erythrocytes use is made of a sample vessel that is walled off into two spaces by a piece of foil with a pore therein. One such space is filled with buffer solution with erythrocytes and the other is filled with buffer solution without erythrocytes. A pressure head is produced acting across the foil for causing transit or passage of the erythrocytes through the opening, whose diameter is less than the major quiescent diameter of an erythrocyte so that information on the deformation capacity may be produced by measuring the transit time. This is done by electrodes placed on the two sides of the opening so that changes in the resistance to alternating current by an erythrocyte in transit may be sensed and the transit time taken. After about 200 transits the readings are processed in a processing unit.