Infusion of fresh frozen plasma (FFP) can rapidly reverse the effects of a vitamin K antagonist like coumadin. This does not depend on hepatic synthetic capacity but may involve a considerable volume load. In addition, FFP may have a higher risk for infectious or other late complications.


dose of coagulation factor activity required in IU =

= ((target level of prothrombin complex as a percent from 0 to 100) - (current estimate of the prothrombin complex in percent)) * (body weight in kilograms)



• The body weight is a surrogate marker for plasma volume.

• Each mL of plasma has about 1 IU of coagulation factor activity.

• The average volume of an FFP product is about 250 mL.

• A quick estimate for plasma volume in the adult (from Chapter 2) is 40 mL/kg in males and 36 mL/kg in females.

• An equation to calculate the prothrombin complex activity from the INR is available in section 04.05.02 .


volume of FFP required in mL =

= (dose of coagulation factor activity required in IU)


number of units of FFP to infuse =

= (volume of FFP required) / 250 mL


The number of units of FFP may be rounded up or down to the nearest integer.


In addition, a small dose of vitamin K may be administered.


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