Cryoprecipitate


Cryoprecipitate, also called cryo for short, is a frozen blood product prepared from blood plasma. To create cryoprecipitate, fresh frozen plasma thawed at 1–6 °C, is then centrifuged and the precipitate is collected. The precipitate is resuspended in a small amount of residual plasma and is then re-frozen for storage. It is often transfused to adults as two 5-unit pools instead of as a single product. One of the most important constituents is factor VIII, which is why cryoprecipitate is sometimes called cryoprecipitated antihaemophilic factor or cryoprecipitated AHF. In many clinical contexts, use of whole cryoprecipitate has been replaced with use of clotting factor concentrates made therefrom, but the whole form is still routinely stocked by many, if not most, hospital blood banks. Cryo can be stored at −18 °C or colder for 12 months from the original collection date. After thawing, single units of cryo can be stored at 20–24 °C for up to 6 hours. If units of cryo are pooled in an open system, they can only be held at 20–24 °C for up to 4 hours. Presently cryo cannot be re-frozen for storage after it is thawed for use if it is not transfused.
Cross-matching is not necessary and all ABO groups are acceptable for transfusion to people of all ABO types.

Medical uses

Medical uses for giving cryoprecipitate include:
Adverse effects reported with the usage of cryoprecipitate include hemolytic transfusion reactions, febrile non-hemolytic reactions, allergic reactions, septic reactions, transfusion related acute lung injury, circulatory overload, transfusion-associated graft-versus-host disease, and post-transfusion purpura.

Composition

Each unit typically provides:
Cryoprecipitate also contains fibronectin; however there are no clear indications for fibronectin replacement.
US standards require manufacturers to test at least four units each month, and the products must have a minimum of 150 mg or more of fibrinogen and 80 IU of factor VIII. Individual products may actually have less than these amounts as long as the average remains above these minimums. Typical values for a unit are substantially higher, and aside from infants it is rare to transfuse just one unit.

History

While the method for the creation of Cryo was discovered by Dr. Judith Graham Pool from Stanford University in 1964, it was initially approved in 1971 by the U.S. Food and Drug Administration under the name Cryoprecipitated AHF for the Hoxworth Blood Center University of Cincinnati Medical Center.