[A rheological method for the measurement of red cell deformability (author's transl)].

In a comparison of the filtration methods of Reid et al. and Schmid-Schönbein et al., the significance of other formed blood elements for the assessment of red cell deformability is established. The hydrodynamic measurements and the morphological inspection of the sieves show the interference of red cell pore passage by thrombozyte aggregates and white blood cells (which were not further identified). In light of these findings, which have since been corroborated by other groups, it is mandatory to remove all cellular blood elements exept the red cells in filtration test of the latter. Lowering the hematocrit improves the reliability of the test. The whole blood filtration test, popular because of its simplicity, cannot be standardized and yields results of questionable relevance.