Haematology 14: Blood Transfusions 2

Question 1

What is the most common cause of acute transfusion reactions ?

Answer 1

TACO - transfusion associated circulatory overload

Question 2

What signs do you see in ABO mismatch transfusion reactions ?

Answer 2

Signs of acute intravascular haemolysis

• fever
• vomiting
• Collapse
• Haemoglobinurea
• hypotension

Chest pain

Question 3

What signs do you get in TACO - transfusion associated circulatory overload ?

Answer 3

SOB
Tachycardia
Hypertension
Fluid overload
Heart failure

Question 4

Give 2 ways in which TACO is different from TRALI ?

Answer 4

TACO responds to Furosemide TRALI does not

TACO has raised JVP TRALI does not

Question 5

Why is male blood less likely to cause TRALI ?

Answer 5

They have not been pregnant so are less likely to have anti-HLA antibodies

Even less likely if the donor has also never received blood himself

Question 6

What happens in Transfusion related acute lung injury (TRALI) ?

Answer 6

• Antibodies against WBCs from the donor blood cause aggregation and deposition of recipients WBCs.
• The aggregates of WBCs deposit in pulmonary capillaries and cause damage

Question 7

Delayed haemolytic transfusion reactions involve …………vascular haemolysis

Answer 7

Extravascular haemolysis

They are IgG mediated

Question 8

What is alloimmunisation ?

Answer 8

• When a recipient receives a blood product with antigens they don’t have themselves.
• They produce antibodies to these antigens

Question 9

What is post transfusion purpura ?

Answer 9

• A delayed transfusion reaction (7-10 days)

- human platelet antigen 1 ( HPA-1) negative patients previously immunised via transfusion or pregnancy

Question 10

Which types of immunoglobulins can cross the placenta ?

Answer 10

IgG

Question 11

Is anti-D given routinely to RhD -ve women in the UK?

Answer 11

Yes at 28-30 weeks and again at 34 weeks

Question 12

What causes febrile non haemolytic transfusion reaction ?

Answer 12

Antibodies against donor leukocytes or HLA molecules.

-Acute onset of mild fever and rigors with no signs of haemolyisis

Question 13

Which people require washed blood transfusions ?

Answer 13

• Previous allergic reaction to blood products

- IgA deficiency

Question 14

Which people require irradiated blood products ?

Answer 14

• Immunosuppressed

Question 15

When would cell salvage be used ?

Answer 15

-Any elective operations which have cardiorespiratory bypass e.g AAA repair, CABG

Question 16

What causes a delayed transfusion reaction ?

Answer 16

• IgG mediated reaction with extravascular haemolysis
• E.g antibodies to Rhesus, kell, duffy and kidd antigens
• 5-10 days later Splenomegaly, jaundice, haemoglobinuria