Cryoprecipitate/Fibrinogen Concentrate Transfusions

Fibrinogen is a critical coagulation protein involved in both primary and secondary hemostasis. Cryoprecipitate preparation was first described by Dr. Judith Graham Pool in 1964 at Stanford University as a product for factor VIII replacement in patients with hemophilia A. Its use for hemophilia A has been superseded by safer, virally inactivated recombinant products. At the present time, cryoprecipitate is only used for fibrinogen replacement for patients with acquired bleeding disorders and hypofibrinogenemia. The product also contains fibrinogen, von Willebrand factor, fibronectin, factor XIII, and platelet microparticles. The hemostatic contribution of these other hemostatic factors in the management of the trauma patient is unknown. Each 10-unit pool must contain typically at least 1.5 g (150 mg per unit) of fibrinogen by regulatory requirements, although may contain substantially more due to donor variability. In contrast, fibrinogen concentrate is a heat-treated, lyophilized fibrinogen powder made from pooled human plasma which must be reconstituted with water prior to injection. Each vial contains between 900 and 1300 mg fibrinogen, as well as 400 and 700 mg human albumin. Hypofibrinogenemia is common in trauma patients on arrival ( 1.5–2.0 g/L). A large clinical trial in trauma hemorrhage to access the effects of early high dose fibrinogen replacement with cryoprecipitate on survival is currently in progress. While we await better evidence on when and how cryoprecipitate should be used, it is reasonable to administer cryoprecipitate if the fibrinogen is under 2 g/L and the patient has serious ongoing hemorrhage. A dose of 10 units (or 50 mg/kg of fibrinogen in pediatrics) or equivalent does of fibrinogen concentrate (4 g) is a reasonable starting dose as such patients will typically be receiving some fibrinogen replacement with each bag of plasma.