Abstract: An apparatus for the measurement of the red blood cell deformability having a measurement cell formed of two electrically insulated compartments clamped mechanically one against the other, with a commercially available multipore membrane therebetween, each of the parts having inlet and outlet orifices as well as a cavity having one electrode and a lateral hole. One of the cavities contains a buffer, the other being intended to receive a suspension of red blood cells consisting of a dilution of a small volume of red blood cells in a large volume of an isotonic conducting buffer, having a volume concentration allowing substantially the transit of a single red blood cell at a time through the multipore membrane, under the action of a device for applying pressure connected to the cavity containing the suspension. An electronic device translates into transit times the electric impedance variations corresponding to the transit of each single red blood cell through the multipore membrane.

Abstract: An apparatus for determining the filterability of red blood cells comprises a first upper transparent block containing at the center a capillary having an inner diameter between 1 and 10 mm, which block is provided with two level detectors; a second lower transparent block, provided with a central duct--facing the capillary of the upper block--inside which duct is housed a drop-taking device, such duct being connected on the one hand to a drain circuit and on the other to a pressure regulating circuit; a filtering membrane housed between the two blocks and a frame for holding the apparatus.First the initial mean flow time of the serum is measured, then the initial mean flow time of a volume of the suspension of cells in the plasma at a given concentration using such apparatus, and then the index of filterability is calculated.