Plasma
is obtained by separating the liquid portion of blood from the cells. One unit of plasma is the plasma taken from a unit of whole blood. Plasma is frozen quickly after donation, usually within 8-24 hours of collection, to preserve the clotting factors. Frozen plasma can be stored up to one year, and thawed shortly before use. Frozen plasma contains all coagulation factors in close to normal concentrations.
Thawed plasma may be transfused up to 5 days after thawing and contains slightly decreased levels of Factor V (66+/-9%) and decreased Factor VIII levels (41+/-8%). Plasma is free of red blood cells, leukocytes and platelets, and in general must be ABO compatible with the recipient's red blood cells. Rh factor need not be considered. Since there are no viable leukocytes, plasma does not carry a risk of transmission of cytomegalovirus (CMV) or graft versus host disease (GVHD).
Plasma transfusion
is indicated in patients with documented coagulation factor deficiencies and active bleeding, or who are about to undergo an invasive procedure. Deficiencies may be congenital or acquired secondary to liver disease, disseminated intravascular coagulation
(DIC), or hemodilution after massive transfusion with red blood cells and crystalloid / colloid solutions. Additionally, plasma transfusion is indicated in the treatment of thrombotic thrombocytopenic purpura (TTP), usually in conjunction with plasma
exchange.
Plasma should not be used for coagulation factor deficiencies for which a safer product is available, i.e. factor VIII and IX concentrates for hemophilia A and B respectively. As well, plasma should not be used for reversal of warfarin (Coumadin)
anticoagulation. This can safely be achieved by giving Vitamin K or holding warfarin two to three days prior to a planned procedure. Rapid reversal of warfarin anticoagulation for life threatening bleeding may be achieved with Kcentra®, a 4 factor
prothrombin complex concentrate (PCC).
Plasma should not be used for volume expansion unless the patient also has a significant coagulopathy and is bleeding.
Dosage:
The volume of one unit of plasma is 200-250 mL. The initial recommended dose for adults is 10 mL/kg, and is 10-15 mL/kg for pediatric patients.
Example: 70 kg patient x 10mL/kg = 700 mL (round up to nearest 200mL) = 800 mL = 4 units of plasma.
When in doubt, Hematology or Blood Bank consultation is advised concerning the dose of plasma.
