Blood transfusion

Question 1

What divides blood groups?

Answer 1

Red cell antigens are expressed on cell surfaces and can provoke antibodies

Question 2

What does ABO gene encode?

Answer 2

Glycosyltransferase

Question 3

What do A and B genes code for?

Answer 3

Transferase enzymes

Question 4

What is the A antigen?

Answer 4

N-acetyl-galactosamine

Question 5

What is the B antigen?

Answer 5

Galactose

Question 6

Are A, B and O genes dominant or recessive?

Answer 6

A and B are codominant and O is recessive

Question 7

What are A group antibodies against?

Answer 7

B

Question 8

What are B group antibodies against?

Answer 8

A

Question 9

What are O group antibodies against?

Answer 9

A and B

Question 10

What are AB group antibodies against?

Answer 10

AB group has no antibodies against A or B

Question 11

Which type is the universal donor?

Answer 11

O

Question 12

Which type is the universal recipient?

Answer 12

AB

Question 13

What does RhD encode?

Answer 13

Protein antigen which crosses membrane and forms pore for unidentified molecule

Question 14

Is RhD gene immunogenic?

Answer 14

Yes

If you are an RhD positive and are exposed to these epitopes then you are very likely to develop antibodies

Question 15

How might an RhD negative individual be exposed to RhD+ cells?

Answer 15

Transfusion

Pregnancy and foetus expresses these cells

Question 16

What are the consequences of an RhD- individual being exposed to RhD+ cells?

Answer 16

Anti-D may be produced

Can cause transfusion reactions or haemolytic disease in the newborn

Question 17

Why is there a diversion pouch for blood donations?

Answer 17

First bit of blood is syphoned off as this is where most of the bacteria would be

Question 18

Why may red cell transfusion be used?

Answer 18

Sever acute anaemia
Improve quality of life in incorrectable anaemia
Prepare a patient for surgery or speed up recovery
To reverse damage from own cells e.g. sickle cell disease

Question 19

At what temperature are red blood cells stored?

Answer 19

4*C

Question 20

At what temperature are platelets stored at?

Answer 20

-22*C

Question 21

What are the uses of platelets?

Answer 21

Massive haemorrhage
Bone marrow failure
Prophylaxis for surgery
Cardiopulmonary bypass

Question 22

What is the most common cause of ABO reactions and how is this prevented?

Answer 22

Vials mislabelled

2 different samples brought in

Question 23

What is the Coombs test (DAGT) used for?

Answer 23

Detecting antibodies on surface of red blood cells

Question 24

Can mums develop antibodies against foetal foreign antigens?

Answer 24

Yes

Important for tolerating RhD+ babies (can inherit from dad)

Question 25

What are some possible complications of haemolytic disease of the newborn?

Answer 25

May die in utero Profound haemolysis Placenta can no longer detoxify the blood Very high bilirubin levels and brain damage

Question 26

What is anti-D prophylaxis for pregnancy?

Answer 26

At about 28 weeks, RhD-negative mothers are given anti-D to mop up red cells from neonate before mother can develop antibodies