Cryoprecipitate

Cryoprecipitate

Cryoprecipitate, also called "Cryoprecipitated Antihemophilic Factor", "Cryoprecipitated AHF", and most commonly just "cryo", is a frozen blood product prepared from plasma.

It is often transfused as a four to six unit pool instead of as a single product. Many uses of the product have been replaced by factor concentrates, but it is still routinely stocked by many hospital blood banks.

Like fresh frozen plasma, compatibility testing is not strictly necessary, but cryo is given as ABO compatible when possible. (Compatibility is reversed for plasma products: AB type is the universal plasma donor and O type is the universal plasma recipient.)

Contents

Composition

Each 15 mL unit typically contains 100 IU of factor VIII, and 250 mg of fibrinogen. It also contains von Willebrand factor (vWF) and factor XIII.

US standards require manufacturers to test at least four units each month, and the products must have an average of 150 mg or more of fibrinogen and 80 IU of factor VIII.[1] 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.

Indications

Indications for giving cryoprecipitate include:[2]

  • Haemophilia - Used for emergency back up when factor concentrates are not available.
  • von Willebrands's disease - Not currently recommended unless last reserve. ddAVP is first line, followed by factor concentrates.
  • Hypofibrinogenaemia (low fibrinogen levels), as can occur with massive transfusions
  • Bleeding from excessive anticoagulation - Fresh frozen plasma contains most of the coagulation factors and is a much better choice when anticoagulation has to be reversed quickly.
  • Massive haemorrhage - RBCs and volume expanders are preferred therapies.
  • Disseminated intravascular coagulation

Manufacture

The product is manufactured by slowly thawing a unit of FFP at temperatures just above freezing (1-6 °C), typically in a water bath or a refrigerator. The product is then centrifuged to remove the majority of the plasma, and the precipitate is resuspended in the remaining plasma or in sterile saline. The product may be pooled and frozen or frozen as individual units.

History

The first publication of the method of concentrating clotting factors from plasma was by Judith Graham Pool at Stanford University in 1964, writing in Nature.[3]

Cryoprecipitate was originally known as "Cryoprecipitate AHF", where AHF stands for "Anti-hemophiliac factor." AHF is now known as Factor VIII.

According to Dr. Charles Abildgaard, who was a Stanford medical resident at the time:

They obtained frozen plasma in very large containers that they got from Japan. They would thaw that and send her [Pool] samples of the liquid parts to assay. She wasn't really finding very much Factor VIII activity, and then someone mentioned to her that when they thawed this large amount of plasma, there was always some mucky stuff at the bottom of it, and she said, "Well, send me some of that, too." She found that at least half of the Factor VIII activity was in the residue. What was happening that, because of the large volume, as the mass thawed, it stayed cold. So this was cryoprecipitate.[4]

Others had been close to discovering cryoprecipitate but failed to make the connection between the lack of plasma clotting activity after thawing and the precipitate. According to Dr. Frederick Rickles:

I made a mistake in an experiment, and instead of putting frozen plasma back in the freezer at the end of the day's experiment, I instead stuck it in the refrigerator. When I came in the next morning, there was all this junk in the bottom of the tube which I spun out, and I used the plasma for my experiment. My experiment didn't work because there was no Factor VIII in it. And I went back and fished the junk out of the trash and assayed the junk and got these outrageously high values for Factor VIII in the junk, and neither Charlie nor I believed it, and so it was one of those things. And sure enough, about a year later Judith Graham Pool discovered cryoprecipitate.[4]

References

  1. ^ "Circular of Information For the Use of Human Blood and Blood Components" (PDF). Archived from the original on 2008-02-27. http://web.archive.org/web/20080227201214/http://www.fda.gov/cber/gdlns/crclr.pdf. Retrieved 2008-02-28. 
  2. ^ Erber WN, Perry DJ (2006). "Plasma and plasma products in the treatment of massive haemorrhage". Best Pract Res Clin Haematol 19 (1): 97–112. doi:10.1016/j.beha.2005.01.026. PMID 16377544. 
  3. ^ Pool JG, Gershgold EJ, Pappenhagen AR (18 July 1964). "High-Potency Antihaemophilic Factor Concentrate Prepared from Cryoglobulin Precipitate". Nature 203 (4942): 312. doi:10.1038/203312a0. PMID 14201780. http://www.nature.com/nature/journal/v203/n4942/abs/203312a0.html. 
  4. ^ a b Resnik, Susan (1999). Blood Saga: Hemophilia, AIDS, and the Survival of a Community. Berkeley: University of California Press. pp. 40–41. ISBN 0520211952. 

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Look at other dictionaries:

  • cryoprecipitate — Precipitate that forms when soluble material is cooled, especially with reference to the precipitate that forms in normal blood plasma which has been subjected to cold precipitation and which is rich in factor VIII. * * * cryo·pre·cip·i·tate .krī …   Medical dictionary

  • cryoprecipitate — n. a precipitate produced by freezing and thawing under controlled conditions. An example of a cryoprecipitate is the residue obtained from fresh frozen blood plasma that has been thawed at 4°C. This residue is extremely rich in a clotting factor …   The new mediacal dictionary

  • cryoprecipitate — The precipitate that forms when plasma is frozen and then thawed; particularly rich in fibronectin and blood clotting Factor VIII …   Dictionary of molecular biology

  • cryoprecipitate — [ˌkrʌɪəʊprɪ sɪpɪtət] noun chiefly Biochemistry a substance precipitated from a solution, especially from the blood, at low temperatures …   English new terms dictionary

  • cryoprecipitate — cryo·precipitate …   English syllables

  • cryoprecipitate — /ˌkraɪoʊprəˈsɪpətət/ (say .kruyohpruh sipuhtuht) noun plasma containing clotting factors, stored in a frozen state, and used to correct coagulation defects, especially in haemophilia …  

  • cryoprecipitate — …   Useful english dictionary

  • Cryoppt — cryoprecipitate …   Medical dictionary

  • Cryoppt — • cryoprecipitate …   Dictionary of medical acronyms & abbreviations

  • Cryosupernatant — The term cryosupernatant (also called cryo poor plasma, cryoprecipitate depleted) refers to plasma from which the cryoprecipitate has been removed. Components The resulting plasma has reduced levels of Factor VIII (FVIII), von Willebrand factor… …   Wikipedia

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