title: Effect of delayed blood processing on the yield of factor VIII in cryoprecipitate and factor VIII concentrate.
abstract: Current standards for the preparation of factor VIII (FVIII) concentrates from human plasma recommend separation of plasma from red cells (RBCs) within 6 hours of blood donation, thereby reducing the volume of plasma from donated whole blood available for processing to FVIII concentrate. The decay of FVIII clotting activity (FVIII:C) in whole blood and plasma stored at 22 and 4 degrees C and the recovery of FVIII:C in cryoprecipitate and FVIII concentrate prepared from plasma separated from whole blood stored overnight at 4 degrees C were investigated. In whole blood stored at 22 degrees C and plasma stored at either 4 or 22 degrees C, 90 percent of the original FVIII:C was present at 6 hours, 80 percent at 12 hours, and 65 to 70 percent at 18 hours. At these times lower levels of FVIII:C were recovered from whole blood stored at 4 degrees C, that is, 84, 68, and 56 percent, respectively. In cryoprecipitates prepared from plasma separated from RBCs after 18 hours' storage at 4 degrees C (18-hour plasma), 43 percent of FVIII:C activity was recovered, as compared with 61 percent recovered from standard plasma separated within 6 hours of donation (6-hour plasma), p less than 0.05. With large-scale preparation of FVIII concentrates, however, the yield of FVIII:C was similar whether 18- or 6-hour plasma was used. Thus FVIII concentrates--but not cryoprecipitates--can be prepared from plasma separated from whole blood stored at 4 degrees C for up to 18 hours without undue loss of potency.
mesh_terms: D000941:Antigens / Q000302:isolation & purification*; D001793:Blood Preservation / Q000379:methods; D001803:Blood Transfusion; D005169:Factor VIII / Q000302:isolation & purification*; D005340:Fibrinogen / Q000032:analysis / Q000302:isolation & purification*; D005353:Fibronectins / Q000032:analysis; D006801:Humans; D010949:Plasma / Q000032:analysis; D013696:Temperature; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D000941:Antigens; D005353:Fibronectins; C026912:cryoprecipitate coagulum; D014841:von Willebrand Factor; D005169:Factor VIII; D005340:Fibrinogen