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Quality analysis of blood components obtained by automated buffy-coat layer removal with a top & bottom system (Optipress (R)II).

2000; National Institutes of Health; Volume: 85; Issue: 4 Linguagem: Inglês

C. Hurtado, Santiago Bonanad, Mariana Soler, Vicente Mirabet, I. López Blasco, Dolores Planelles, Aon Miguel,

Blood groups and transfusion

There are Council of Europe recommendations for the quality of blood components. We analyzed the quality of blood components processed by a top & bottom system (Optipress((R)) II), the routine method used in our blood bank, to test whether the components reached the recommended quality.Blood was collected in triple CPD-SAGM bags (Optipac((R)) Baxter). Whole blood (WB) was centrifuged at 4,158 g for 14 min before separation by an automated top & bottom system (Optipress((R) )II). Platelet concentrate (PC) was prepared by pooling four isogroup buffy-coat (BC) units before low-speed centrifugation, and transferring the supernatant (4 BC-PC) to a 5-day storage bag (PL732, Baxter). An alternative approach involved PC preparation from a single BC unit by adding approximately 70 mL of plasma before centrifugation, followed by transfer of the platelet concentrate (1BC-PC) to a 300 mL Teruflex((R)) transfer bag. Both 4 BC-PC and 1 BC-PC were stored in a flat agitator at 22 degrees C for up to 5 days after collection. Cell counts were determined, along with hemoglobin and hematocrit in a Sysmex K-800 cell counter. The pH was determined on day 5 at 22 degrees C. Weights were measured and volumes were calculated based on specific gravity. Statistical analyses were carried out using the Kolmogorov-Smirnov test as a normality distribution test, the t-test for parametric values and Wilcoxon's test as a non-parametric test. Statistical significance between samples was considered to have been reached when p<0.05.The best parameters for configuring the system were: strength 25; BC volume 33-55; level of BC 5.5. Red blood cell (n = 1,434) volume was 279+/-20 mL, with 54.92+/-7.16 g of hemoglobin. More than 96% of units had fewer than 1.2x10(9) white blood cells. Fresh plasma volume (n = 803) averaged 279+/-19 mL, with a white blood cell contamination of fewer than 0.1x10(9)/L in all samples examined (n = 23). Platelet recovery in BC was 92+/-9% of platelets present in WB; the percentage of removed leukocytes was 74+/-10%, and between 13 and 15% of RBCs were lost in the BC (95% confidence interval). The BC volume (n = 1,037) fitted the target volume of 60 mL, except for some devices, when Optipress II((R)) lost the configuration for this parameter. Of 4 BC-PCs 80.3% yielded more than 0.6x10(11) platelets per unit, whereas this criterion was only met by 59.7% of 1 BC-PCs, and a greater proportion of 1 BC-PCs (58.8%) showed pH values within the range of 6.5-7.4 after 5 days of storage in comparison with 4 BC-PCs (44.25%).Optipress II((R)) provides standardized, leukocyte-poor blood components. Council of Europe requirements were met in a large percentage of red-cell concentrates, with less than 92 and 74% of the original platelets and leukocytes, respectively, and a small hemoglobin loss per unit. The system gave an optimal yield in terms of plasma volume. The top & bottom technique allowed us to reduce the number of blood units per platelet concentrate from 6 to 4 units, with similar platelet yields compared with traditional procedures. Nevertheless, the storage conditions must be improved to satisfy all Council of Europe requirements for platelet concentrates.