Plasma Products

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Three plasma products are generally available today: Fresh Frozen Plasma (FFP), Plasma frozen within 24 hours after Phlebotomy (FP24) and Thawed Plasma.  All of these products are usually prepared from a unit of whole blood, but may also be collected by apheresis. Each bag of plasma prepared from whole blood has a volume between 175 and 250 mL. Plasma prepared by apheresis contains a volume of 400 to 600 mL.

The major difference between FFP and FP24 is that FFP is separated from a unit of whole blood and frozen at -18^oC within 8 hours after collection, whereas a unit of FP24 is frozen within 8 to 24 hours after collection.  Both products can be stored frozen for up to 1 year and expire 24 hours after thawing. Because of the delay in freezing, the Factor VIII content of FP24 is 20 to 40% lower than the pre-storage concentration, compared to a 10 to 20% decrease for FFP. The decreased level of Factor VIII does not prevent FP24 from correcting a coagulopathy because the Factor VIII concentration of the unit remains above the minimal hemostatic level of 30% and many patients have elevated Factor VIII levels because it is an acute phase reactant.

If a unit of FFP or FP24 is not transfused within 24 hours after thawing, it can be relabeled as Thawed Plasma and stored for an additional 4 days at 1 to 6^o C. The FDA has not issued guidance on conversion of FP24 to Thawed Plasma, but this appears to be common practice.  All coagulation factors are maintained at relatively normal levels, except for Factor VIII which declines to 40% of the prestorage level.  Conversion of FFP or FP24 decreases product wastage and improves turnaround time in emergency situations because it has already been thawed and can be issued immediately.

Pre-transfusion crossmatching of plasma is not necessary.  Units of FFP should be ABO compatible whenever possible. Alternative ABO groups may be substituted as long as the recipients’ red blood cells are compatible with anti-A or B antibodies present in the donor plasma.  The following table provides guidelines for selection of compatible FFP units:

ABO Compatible FFP