Plasma Infusion

Related Information: Plasma infusion, HUS treatment therapy, FFP (fresh frozen plasma)

Plasma is the fluid part of blood and contains blood cells, enzymes, hormones and nutrients required to the body. Hemolytic Uremic Syndrome (HUS) is mostly treated by plasma therapy, which involves the addition of fresh plasma to newborns, children inherited or people who acquired HUS. Soon after the detection of HUS in a person, plasma therapy is begun.

For those who inherited HUS, FFP (fresh frozen plasma) is administered intravenously for replacing the missing or altered ADAMTS13 enzyme. For those who had acquired HUS, plasmapheresis or plasma exchange is carried out. This removes the antibodies in the blood which damages ADAMTS13 enzyme. If this is unavailable, FFP is given till it is available.

Treatment with FFP or plasma exchange continues till there is an improvement in symptoms and there are negative blood tests. It can last for days or weeks based on the patient’s condition. Though recovered from HUS, some people experience flare-ups. This can occur immediately or after some time. If this occurs, the treatment needs to be restarted.

FFP represents the plasma separated from a single unit of whole Blood and later frozen to below –20°C within the next eight hours after collection. FFP includes normal amounts of several coagulation factors and lacks RBCs, WBCs and platelets. It cannot be called a concentrate of the clotting factors. A single unit is roughly 225 ml and needs to be ABO that is compatible with the red cells of the recipient. Rh factor is not a matter of importance.

FFP is recommended for patients who are found to be deficient in coagulation factors, especially for those who are bleeding actively or about to undertake an invasive procedure. The causes for such deficiencies involve liver disease, congenital deficiency, anticoagulation with warfarin, massive red cells or crystalloid solutions transfusions, etc. Such factor deficiencies if very severe that it is clinically significant, are associated with continuation of the screening tests meant for checking coagulation of blood. The tests include partial thromboplastin time or prothrombin time. It must be a minimum time of 1.5 times the control value or at least an INR of nearly 1.6.

FFP proves to be the recommended treatment for HUS and TTP (thrombotic thrombocytopenic purpura) normally in association with plasma exchange. This procedure is not suitable for nutritional support/ supplements or volume expansion. Besides, there are immune globulin preparations available for the addition of immune proteins which can be used instead of FFP. In case if warfarin anticoagulation is reversed, it needs to be treated with Vitamin K which is effective compared to FFP. This can be done if it is possible to allow the clotting factors to come back to their normal hemostatic levels in 2-3 days. FFP is suitable for extremely bleeding patients in association with RBCs in order to avoid dilution of clotting factors/ proteins.

One ml of FFP per Kg of patient weight can increase the clotting factors by nearly 1%. FFP needs to be used soon after thawing and at the least within 24 hours. The required quantity of FFP is based on the patient’s condition. Clotting factor activity must be determined by specific assays or at least some screening tests in emergencies.