Blood transfusion

Question 1

What are blood group due to?

Answer 1

Antigens on the surface of the red blood cells

Question 2

What do ABO genes encode?

Answer 2

Glycosyltransferase

Question 3

What are glycans added to?

Answer 3

Protein or lipid on the red blood cell

Question 4

What do the A and B genes code for?

Answer 4

Transferase enzyme

Question 5

What is the A antigen?

Answer 5

N-acetyl-galactosamine

Question 6

What is the B antigen?

Answer 6

Galactose

Question 7

What is the difference between A and B and O?

Answer 7

‘O’ gene is non-functional allele (doesn’t put anything on the red cell)

Question 8

How are A and B classed as?

Answer 8

Dominant

Question 9

What is O classed as?

Answer 9

Recessive

Question 10

What do people with blood group A have antibodies against?

Answer 10

Blood group B

Question 11

What do people with blood group B have antibodies against?

Answer 11

Blood group A

Question 12

What do people with blood group O have antibodies against?

Answer 12

Blood groups A and B

Question 13

Do blood group AB have antibodies?

Answer 13

No

Question 14

Which antibody is responsible for immune tolerance?

Answer 14

IgM

Question 15

If a patient is blood group A. what donor blood can the receive?

Answer 15

A and O

Question 16

If a patient is blood group B. what donor blood can the receive?

Answer 16

B and O

Question 17

If a patient is blood group AB. what donor blood can the receive?

Answer 17

A, B and O

Universal recipient

Question 18

If a patient is blood group O. what donor blood can the receive?

Answer 18

O

Question 19

If a patient is blood group A. what donor plasma can the receive?

Answer 19

A

Question 20

If a patient is blood group B. what donor plasma can the receive?

Answer 20

B

Question 21

If a patient is blood group AB. what donor plasma can the receive?

Answer 21

AB

Question 22

If a patient is blood group O, what donor plasma can the receive?

Answer 22

O

Question 23

What needs to be checked and recorded before someone can donate blood?

Answer 23

• Extensive ‘behavioural’ screening
• Sex, age, travel, tattoos
• Tested for ABO and Rh blood groups
• Screened for HepB/C/E, HIV, syphilis
• Variably screened for: HTLV1, malaria, West Nile virus, Zika virus…

Question 24

What are possible indications for a blood transfusion?

Answer 24

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 25

What is blood separated into?

Answer 25

Plasma Buffy coat Red blood cells

Question 26

What does plasma contain?

Answer 26

* Clotting or coagulation factors * Albumin * Antibodies

Question 27

What does the buffy coat contain?

Answer 27

* Platelets | * White cells/ leucocytes

Question 28

How is compatible blood chosen?

Answer 28

* Blood sample (EDTA tube) * Two sample policy * Group and Screen/Save * Cross matching

Question 29

How many samples of blood need to be taken before giving blood to a patient?

Answer 29

2 sample (policy)

Question 30

What does group and screen include?

Answer 30

* ABO and RhD type * Checked against historical records * Screen for allo-antibodies in serum

Question 31

What is Coombs test used for?

Answer 31

Trying to detect antibodies on the surface of blood cell

Question 32

What will happen if there is a reaction between antigens on the red blood cells an it is an IgM reaction?

Answer 32

Blood cells will clump together

Question 33

What will happen if there is a reaction between antigens on the red blood cells an it is an IgG reaction?

Answer 33

The blood cells wont clump together

Question 34

What is direct combs test used for?

Answer 34

Checks if the immune system is destroying the red blood cells as there aren’t enough of them

Question 35

What does indirect coombs test check?

Answer 35

to make sure donated blood is compatible with the patients

Question 36

What are some examples of what direct coombs testing looks for?

Answer 36

* autoimmune haemolytic anaemia * passive anti-D * haemolytic transfusion reactions

Question 37

What are some examples of what indirect coombs testing looks for?

Answer 37

Cross matching

Question 38

How is the transfusion of blood cells carried out?

Answer 38

* Stored in a fridge at 4oC * Transfuse over 2-4 hours * 1 unit increments hemoglobin by about ~5 g/L

Question 39

Platelets

Answer 39

1 dose platelets is the equivalent 4 blood donations(=4 pooled or 1 apheresis donor) Increases platelet count by about 30.109/L Stored at ~22oC Short shelf life- 7 days Transfuse over 20-30 minutes

Question 40

What are the uses of platelet transfusion?

Answer 40

Massive haemorrhage- Keep platelet count above 75x109/l Bone marrow failure- keep platelet count <10-15 × 109/litre, or <20 × 109/litre if additional risk, e.g. sepsis Prophylaxis for surgery • Minor procedures- keep platelet count 50x109/l; • More major surgery keep platelet count 80x109/l; CNS or eye surgery 100x109/l Cardiopulmonary bypass- use only if bleeding

Question 41

Plasma

Answer 41

1 unit from 1 unit of blood | Stored frozen, allow 30 minutes to thaw

Question 42

What are possible uses of plasma transfusion

Answer 42

* Massive haemorrhage * DIC with bleeding * Prophylaxis

Question 43

What is Cryoprecipitate?

Answer 43

* Made from gradually thawing FFP | * It is a fibrinogen concentrate