Blood groups and transfusions

Question 1

What is an antibody?

Answer 1

Protein produced by the immune system in response to a specific antigen, to neutralise and destroy it.

Question 2

What is an antigen?

Answer 2

Specific proteins our body produces to allow white blood cells to distinguish between self and non-self.

Question 3

What is agglutination?

Answer 3

The clumping of microbes or blood cells caused by antibodies and the mixing of incompatible blood types.

Question 4

How does coagulation occur?

Answer 4

-clotting factors in plasma
formation of insoluble protien threads=fibrins
- fibrins from a mesh, trap blood cells, plasma, platelets
- mesh with trapped material=clot/thrombus
- threads stick to broken vessels, hold clots in place= a scab

Question 5

What is clot retraction?

Answer 5

• fibrin network contracts which pulls the damaged vessels together
• as retraction occurs, fluid (serum) squeezes out of clot
• clot dries= scab
• scab prevent entry of infecting micro-organisms

Question 6

What are clotting factors?

Answer 6

Chemical substances in plasma that allow blood to clot (always proteins)

Question 7

What is haemophilia?

Answer 7

An inherent disorder where blood clumps slowly or not at all

Question 8

How does blood clotting occur? (3)

Answer 8

• Vasoconstriction
• Platelet plug
• Coagulation

Question 9

How does a platelet plug function?

Answer 9

-Blood vessels have smooth internal walls that become rough when damaged
-platelets stick, then attract others which results in a build up
-plug reduces blood loss
-releases vasoconstrictor like substances to enhance vessel constriction of lumen
Platelet plugs stop small almost daily tears

Question 10

Function of platelets

Answer 10

Adhere to lining of damaged blood vessel and form a scaffold for coagulation of blood to form a clot (scab)

Question 11

How does vasoconstriction function?

Answer 11

• small arteries walls constrict immediately after being damaged to reduce blood flow
• so, blood less decreases

Question 12

What are vasoconstrictors?

Answer 12

• Decrease the lumen of a blood vessel

- restriction of blood flow

Question 13

What are vasodilators?

Answer 13

• substances that relax smooth muscle surrounding arteries

- increases lumen size=increase blood flow

Question 14

What are the types of blood transfusions?

Answer 14

• Whole blood
• Platelet concentrate
• red cell concentrate
• cryoprecipitate
• immunoglobulins
• autologous transfusion

Question 15

What is whole blood transfusion?

Answer 15

-blood is taken from a donor
-chemical is added to prevent clotting
For sever blood loss in a patient

Question 16

What is platelet concentrate transfusion?

Answer 16

-after being separated, portion of blood containing platelets is given to a recipient
For abnormal platelets + reduced platelet number

Question 17

What is red blood cell concentrate transfusion?

Answer 17

Most used component
-blood is spun in centrifuge at high speed
-heavy RBC’s sink while light plasma stays at the top (due to being more dense)
For heart disease or ammonia patients

Question 18

What is cryoprecipitate transfusion?

Answer 18

-Freezing plasma
-thawing it out slowly
-when thawed, cryoprecipitate remains solid (contains clotting factors)
For haemophilia treatment or severe blood loss

Question 19

What is autologous transfusion?

Answer 19

When own patients blood is used as treatment

• collected 4 weeks prior to op.
• eliminates disease risk of blood mismatch

Question 20

What is immunoglobulins transfusion?

Answer 20

-group of proteins is extracted that shares characteristics similar to antibodies
-given to antibody deficient patients
For tetanus treatment and people with no disease immunity

Question 21

Info on blood type A

Answer 21

• A antigens
• B antibodies
• Can receive B and O
• Can donate to A and AB

Question 22

Info on blood type B

Answer 22

• B antigens
• A antibodies
• Can receive B and O
• Can donate to B and AB

Question 23

Info on blood type O

Answer 23

• no antigens
• A and B antibodies
• Can receive 0
• Can donate to AB, A, B, O

Question 24

Info on blood type AB

Answer 24

• A and B antigens
• no antibodies
• Can receive A, B, O, AB
• Can donate to AB

Question 25

Info on Rh blood groups

Answer 25

• Has protein, ABO doesn’t
• Rh positive people: no antibodies, Rh antigens
• Rh negative people: anti-Rh antibodies, no antigens