Background: As blood centers prepare fewer plasma products from female donors to avoid HLA antibodies, the standard starting material for cryoprecipitate (cryo), fresh-frozen plasma (FFP), might become increasingly scarce. A unit of cryo must contain at a minimum 80 IU of VIIIC and 150 mg of fibrinogen. Plasma frozen within 24 hours after phlebotomy (FP24) contains nearly equivalent levels of clotting factors as FFP at the time of thawing and, although not AABB/FDA approved for this purpose, might be a suitable starting material for cryo (cryo24) manufacture.
Study design and methods: FP24 was collected from 20 male donors and cryo24 was subsequently prepared according to standard blood center protocols. The cryo24 was then thawed and VIIIC, von Willebrand factor (VWF) antigen, and fibrinogen levels were measured in these cryo24 units and compared to the corresponding levels in 20 randomly selected units of standard cryo (prepared from FFP).
Results: The mean (+/-SD) levels in cryo and cryo24 at the time of thawing were as follows: fibrinogen (mg/unit) 455.8 (+/-172.6) and 575.8 (+/-185.9; p = 0.04), VIIIC (IU/unit) 216.1 (+/-52.3) and 252.4 (+/-70.1; p = 0.07), and VWF (IU/unit) 448.1 (+/-118.9) and 505.9 (+/-135.1; p = 0.16), respectively. All units of standard cryo and cryo24 met the current minimum content standards.
Conclusion: All units of cryo24 in this pilot study met the current minimum content standards for cryo. While clinical studies of its efficacy are warranted, cryo24's in vitro characteristics are at least equivalent to that of standard cryo.