Fluid portion of blood.
The composition of plasma is placed at >90% water.
Remains fluid until 25-30% of plasma fibrinogen is cleaved by thrombin, allowing fibrin to polymerize while simultaneously promoting thrombin activation of plasma factor XIII.
Contains ions, inorganic molecules and organic molecules.
Normal plasma volume is about 5% of body weight, approximately 3500 cc in a 70 kg adult man.
Clots on standing.
When whole blood clots, the remaining fluid is serum.
Serum contains the same composition as plasma without fibrinogen, factors II, V, and VIII.
Serum has higher serotonin levels than does plasma.
Nearly 4 million units transfused annually in the U.S.
Estimated that approximately 50% of plasma transfusions are outside of published guidelines.
Most common reason for plasma transfusions is the correction of abnormal results of coagulation tests before an invasive procedure.
Studies have shown that there is no correlation between mild to moderate coagulation abnormalities of INR 2 or less than two and bleeding complications in patients undergoing basic invasive percutaneous procedures.
Plasma transfusion does not reliably normalize mild to moderate elevations in INR, and in the absence of active hemorrhage, it is not recommended for the correction of mild coagulopathy.
Studies have failed to establish a relationship between mild moderate elevations in INR and increased procedure bleeding risk, utility of decreasing an elevated INR for the prevention of bleeding complications is theoretical.
In a study of patients undergoing interventional radiology procedures, preprocedure plasma transfusion giving in the setting of an elevated INR was associated with increased periprocedural red blood cell transfusion use (Warner MA entail).