Blood Transfusion

Question 1

What do each blood group have antigens against?

Answer 1

If blood group A, have antibodies against B
If blood group B, have antibodies against A
If blood group O, have antibodies against A and B
If blood group AB, have no antibodies against A and B

Question 2

What is the donor/recipient compatibility for each blood group for red blood cells?

Answer 2

A- A and O
B- B and O
AB- A, B, AB and O
O- O

Question 3

What is the donor/recipient compatibility for each blood group for freshly frozen plasma?

Answer 3

A- A and AB
B- B and AB
AB- AB
O- A, B, AB and O

Question 4

Describe how someone is rhesus positive or negative

Answer 4

There are two antigens in the RhD blood group system- RHD and RHCE. Deletions of one of these antigens is common in European populations
RhD negative individuals do not have the RHD antigen

Question 5

When is anti-D produced?

Answer 5

RhD negative individuals can develop anti-D if they are exposed to RhD +ve cells. This can occur during transfusion or pregnancy

Question 6

What are the possible complications of anti-D production?

Answer 6

Transfusion reactions

Haemolytic disease of the newborn.

Question 7

What are the indications for red cell transfusion?

Answer 7

• To correct severe acute anaemia, which might otherwise cause organ damage
• To improve quality of life in patient with otherwise uncorrectable anaemia
• To prepare a patient for surgery or speed up recovery
• To reverse damage caused by patient’s own red cells (Sickle Cell Disease)

Question 8

What are the indications for platelet transfusion?

Answer 8

• Massive haemorrhage
• Bone marrow failure
• Prophylaxis for surgery
• Cardiopulmonary bypass (only if bleeding)

Question 9

What two blood components can be made from plasma?

Answer 9

Fresh frozen plasma (FFP)

Cryoprecipitate

Question 10

When is cryoprecipitate given?

Answer 10

If the patient has low fibrinogen

Question 11

What steps need to be taken when organising a transfusion?

Answer 11

Two samples must be taken to check patients blood type.

If using frozen components then need to give time to thaw (30 mins for FFP, 20 mins for cryo)

Question 12

What is Coombs test looking for?

Answer 12

For other antigens in the red cells

Question 13

What can Coombs test test for?

Answer 13

Direct test:
-Autoimmune haemolytic anaemia
-Passive anti-D 
-Haemolytic transfusion reactions
Indirect test- cross matching

Question 14

How does haemolytic disease of the newborn develop?

Answer 14

If pregnant and RhD negative and developed an anti-D, which is always IgG then IgG will cross the placenta. If anti-D is developed but the baby is RhD +ve then haemolytic disease of the newborn can develop

Question 15

What are the complications of haemolytic disease of the newborn?

Answer 15

Anaemia
Jaundice
Death of the baby

Question 16

How is haemolytic disease of the newborn prevented?

Answer 16

Prophylactic anti-D given at 28 weeks or following any sensitising events (RTA, abruption etc)

Question 17

How is haemolytic disease of the newborn managed?

Answer 17

Careful observation with antibody titres + doppler ultrasound
Intrauterine transfusion of RhD -ve blood