Cryoprecipitate

Cryoprecipitate

Clinical data
Other names	Cryo, cryoprecipitated antihaemophilic factor, cryoprecipitated AHF
Identifiers
ChemSpider	none

Cryoprecipitate,also calledcryofor short, is a frozenblood productprepared fromblood plasma.To create cryoprecipitate,fresh frozen plasmathawed to 1–6 °C is thencentrifugedand the precipitate is collected. The precipitate is resuspended in a small amount of residual plasma (generally 10–15 mL) and is then re-frozen for storage. It is oftentransfusedto adults as two 5-unit pools instead of as a single product. One of the most important constituents isfactor VIII(also called antihaemophilic factor or AHF), which is why cryoprecipitate is sometimes calledcryoprecipitated antihaemophilic factororcryoprecipitated AHF.In many clinical contexts, use of whole cryoprecipitate has been replaced with use ofclotting factorconcentrates made therefrom (where available), but the whole form is still routinely stocked by many, if not most, hospitalblood banks.Cryo can be stored at −18 °C or colder for 12 months from the original collection date.After thawing, single units of cryo (or units pooled using a sterile method) 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(compatibility testing) 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:

• Haemophilia– Used for emergency back up when factor concentrates are not available.
• von Willebrand disease– Not currently recommended unless last reserve.ddAVPis first line, followed by factor concentrates.
• Hypofibrinogenaemia(lowfibrinogenlevels), as can occur with massive transfusions
• Afibrinogenemia
• Bleeding from excessiveanticoagulation– Fresh frozen plasma contains most of the coagulation factors and is an alternative choice when anticoagulation has to be reversed quickly.
• Massivehaemorrhage–RBCsandvolume expandersare preferred therapies.
• Disseminated intravascular coagulation
• Uremic bleeding tendency
• Reversing tpa (with aminocaproic acid)

Adverse effects

Adverse effects reported with the usage of cryoprecipitate include hemolytictransfusion reactions,febrile non-hemolytic reactions, allergic reactions (ranging fromurticariatoanaphylaxis), septic reactions,transfusion related acute lung injury,circulatory overload, transfusion-associatedgraft-versus-host disease,andpost-transfusion purpura.

Composition

Each unit (around 10 to 15 mL) typically provides:

• Fibrinogen150–250 mg with ahalf-lifeof 100–150 hours
• Factor VIII80–150 U with a half-life of 12 hours
• Factor XIII50–75 U with a half-life of 150–300 hours.
• von Willebrand factor100–150 U with a half-life of 24 hours

Cryoprecipitate also containsfibronectin;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 totransfusejust one unit.

History

While the method for the creation of Cryo was discovered by Judith Graham Pool fromStanford Universityin 1964,it was initially approved in 1971 by theU.S. Food and Drug Administrationunder the nameCryoprecipitated AHFfor the Hoxworth Blood CenterUniversity of Cincinnati Medical Center.