[Changes in the thrombocyte count and density in thrombocyte concentrates during storage with reference to...

25 platelet concentrates prepared from fresh whole blood are stored for 5 days in different bags: smooth inside surface: Poli-Olefine PL 732 (Fenwal) n = 11; PVC F 702 (Biotest) n = 5; rhombic inside surface: PVC BBC 1030 (Terumo) n = 9. Samples are separated with a Perkoll gradient of densities (1.053, 1.069, 1.079 and 1.095). The platelet count of each sample of the density fractions are determinated in a Neubauer counting chamber. Moreover, pH and pCO2 are estimated. The platelet count is reduced during storage in bags with rhombic inside structure. The analysis of pH and pCO2 do not show significant differences between the groups. In platelet concentrates with counts greater than 1200 x 10(9)/L, stored in bags with a rhombic inside surface, the highest portion of light (density 1.053) and the lowest portion of heavy (density 1.079) platelets are found at the end of storage time.