Measurement of erythrocyte deformability by cell transit analyser

Abstract

Erythrocyte deformability (filterability) as measured by the Cell Transit Analyser was studied in the presence and absence of contaminating leucocytes and platelets. The effects of two anticoagulants (lithium heparin and K₂ EDTA), no anticoagulant (defibrinated blood) and two buffers (HEPES and phosphate) were also evaluated. Erythrocyte transit time was unaffected by contaminating leucocytes (range 0–78.6 × 10⁹/l) but was influenced slightly by the presence of platelets. False rapid transit times were obtained using EDTA anticoagulant and/or phosphate buffer which may in part be a consequence of calcium removal from the erythrocyte membrane. The combination of lithium heparin anticoagulant and HEPES buffered saline gave optimal transit times for human erythrocytes.