Cryoprecipitate is a specialized blood product used primarily to manage severe bleeding when a patient’s clotting proteins are dangerously low. It is a concentrated source of specific coagulation factors derived from fresh frozen plasma (FFP), not a standard blood transfusion. Developed in the 1960s, it is now a standard tool in emergency medicine and trauma centers for correcting defects in the body’s ability to form a clot. Its use focuses on replacing factors consumed rapidly during massive hemorrhage or those that are congenitally deficient.
Components and Function of Cryoprecipitate
Cryoprecipitate is prepared by slowly thawing FFP at a low temperature (1 to 6 degrees Celsius), causing cold-insoluble proteins to precipitate out. This precipitate is collected, resuspended in a small amount of plasma, and refrozen for storage. The primary active ingredient in this concentrated product is fibrinogen (Factor I).
Fibrinogen is converted into fibrin, which acts as the final “glue” to form a stable blood clot. Each unit of cryoprecipitate must contain a minimum of 150 milligrams of fibrinogen. The product also contains Factor XIII (which stabilizes the fibrin clot), von Willebrand factor (vWF), and Factor VIII. Due to its low volume and high concentration of these specific proteins, cryoprecipitate provides targeted factor replacement without the large fluid volume associated with FFP.
Specific Medical Conditions Requiring Treatment
Cryoprecipitate is indicated when a patient is bleeding and has a severe fibrinogen deficiency. The most common trigger is a fibrinogen level below 100 to 150 milligrams per deciliter (mg/dL). This is significantly lower than the normal adult range, which is typically between 200 and 400 mg/dL.
The most frequent scenario requiring cryoprecipitate is massive hemorrhage, such as severe trauma, major surgery, or obstetric bleeding. Rapid blood loss and replacement can dilute the patient’s clotting factors, including fibrinogen. For obstetric hemorrhage, a target fibrinogen level of at least 200 mg/dL is often recommended due to naturally elevated levels during pregnancy.
Cryoprecipitate is also necessary for acquired conditions that rapidly consume clotting factors. Disseminated Intravascular Coagulation (DIC), where the clotting system is abnormally activated, leads to widespread consumption of fibrinogen. It is also used to manage uremic bleeding associated with kidney failure, which relates to impaired platelet function and vWF activity.
For inherited disorders like Hemophilia A (Factor VIII deficiency) or von Willebrand disease (vWD), specific factor concentrates are the preferred treatment. Cryoprecipitate is generally reserved for these congenital conditions only if concentrates are unavailable. Its primary role remains the targeted replacement of low fibrinogen in actively bleeding patients or those undergoing high-risk invasive procedures.
Administering Cryoprecipitate
Cryoprecipitate is stored frozen at -18°C or below, giving it a shelf life of up to a year. Before administration, the product must be thawed, which takes approximately 30 minutes in a controlled environment. Once thawed, it must be used relatively quickly, usually within four to six hours to maintain effectiveness.
Dosing is typically weight-based or given as a “pool” of multiple single-donor units. An adult dose often consists of five to ten units, expected to raise the patient’s fibrinogen level by 50 to 100 mg/dL. The product is administered intravenously through a standard blood administration set, which includes a filter.
Because cryoprecipitate contains plasma but has a low volume, strict ABO blood type matching is not always necessary, except in neonates and small children. Following the infusion, laboratory tests, particularly fibrinogen level measurements, are performed to ensure the treatment goal has been met. This monitoring guides whether additional doses are needed to stop the bleeding.
Risks Associated with Transfusion
Like all blood product transfusions, cryoprecipitate administration carries certain risks that are carefully managed. Allergic reactions are the most common adverse event, ranging from mild symptoms like hives and itching to rare, severe anaphylaxis. Patients are closely monitored during and after the infusion to quickly catch any signs of a reaction.
Donor screening procedures have made the transmission of infectious diseases rare, but a theoretical risk remains for viral infections (such as HIV and hepatitis) and other pathogens. Since a single dose is often pooled from multiple donors, the potential for exposure to different infectious agents increases slightly.
Other serious complications include Transfusion-Related Acute Lung Injury (TRALI), which causes acute respiratory distress, and Transfusion-Associated Circulatory Overload (TACO). TACO is a risk when the patient’s circulatory system cannot handle the volume of the infused product, though the small volume of cryoprecipitate makes this less likely than with other blood components. There is also a risk of thrombotic complications, or unwanted clotting, particularly if fibrinogen levels are raised too high.