Transfusion Reactions

Question 1

what are some ways that transfusion reactions can be classified? Give 3 ways

Answer 1

As delayed or acute (w/in 24 hours); as infectious or noninfectious; or as immune or nonimmune

Question 2

describe the basic workup for evaluation of post-transfusion reaction sample for an acute transfusion reaction

Answer 2

Clerical check of info on post-rxn sample, documentaiotn, and blood bag match; Hemolysis check for free Hg in plasma (pink discoloration); DAT to check for sensitized cells; verify ABO

Question 3

what are possible symptoms of an IMMUNE -mediated acute HTR?

Answer 3

abdominal/chest/flank pain; pain at infusion site; sense of impending doom; hemoglobinemia and -uria; hypotension, renal failure, shock, DIC.

Question 4

what may be the only sign of an acute HTR in the anesthetized patient?

Answer 4

red/dark urine or diffuse oozing

Question 5

how small of a volume of incompatible blood can cause an HTR?

Answer 5

10 mL!

Question 6

What antibodies are associated with the most severe HTRs?

Answer 6

the ABO

Question 7

what is formed as a result of IgM antibody + antigen that causes activation of the complement cascade?

Answer 7

immune complexes

Question 8

name the four major events of the acute HTR that occur as a result of immune complexes forming

Answer 8

1. complement cascade activated
2. MAC activated as a result
3. secretion of vasoactive amines and mediators of inflammation
4. activation of the Coagulation cascade

Question 9

List downstream events in an acute HR caused by the coagulation cascade (potentially)

Answer 9

the cascade causes DIC, diffuse intravascular coagulation, which leads to bleeding because the coag factors are used up

Question 10

what are the hallmarks of intravascular hemolysis and which part of an acute HTR causes this

Answer 10

hemoglobinemia and hemoglobinuria; the MAC

Question 11

How can an acute HTR lead to renal failure?

Answer 11

a combo of the vascular collapse due to the vasoactive amines plus DIC-caused microthrombi in the kidneys

Question 12

If the complement cascade is not completed in a HTR, how are the red cells lysed?

Answer 12

In the spleen mainly, by its macrophages of the MPS/RES, extravascular hemolysis

Question 13

what type of hemolysis is typical of non-ABO HTRs and DHTRs

Answer 13

extravascular