Bleeding

Question 1

how can infection lead to multi-organ failure

Answer 1

• infection
• sepsis-systemic infection
• intravascular TF exposure
• systemic coagulation –> microvascular clots
• consumption of clottign factors –> bleeding
• multiple organ failure

Question 2

what causes intravascular activation of coagulation

Answer 2

loss of localisation

Question 3

why uncontrolled bleeding can’t stop

Answer 3

• coagulation factors consumed at faster rate than produced

- platelets consumed at faster rate than produced

Question 4

what factors does vitamin K help

Answer 4

• factor ii
• factor vii
• factor ix
• factor x
• protein c
• protein s

Question 5

what do completed forms of factors ii, vii, ix, x and proteins c & s do

Answer 5

• more effective binding of Ca2+ and phospholipids on platelet surface

Question 6

what are VKA monitored by

Answer 6

• INR –> based on PT assay

- keep blood levels within therapeutic window

Question 7

what are circulating anticoagulants and what types are they split into

Answer 7

• antibodies that neutralise clotting factors activity

- lupus & factor viii antibodies

Question 8

what are lupus anticoagulants

Answer 8

• antibodies to phospholipid binding sites on clotting Fs

- prevent factors accumulating on phospholipid surfaces

Question 9

what are factor viii anticoagulants

Answer 9

• antibodies

- same profile as haemophilia A

Question 10

Defects in platelet-vessel wall interaction

Answer 10

Von Willebrand syndrome.​

Bernard–Soulier syndrome.​

Question 11

Defects in platelet-platelet interaction

Answer 11

Glanzmann thrombasthenia.​

Congenital afibrinogenemia.​

Question 12

Defects in platelet granules, secretion and signal transduction.​

Answer 12

Wiskott-Aldrich Syndrome

Question 13

what is haemophilia

Answer 13

• X-linked disease

Question 14

how many cases of haemophilia are mutations

Answer 14

• 30%

Question 15

what does haemophilia result in

Answer 15

insufficient thrombin generation

Question 16

what factor is deficient in haemophilia A

Answer 16

• Factor VIII

Question 17

what factor is deficient in haemophilia B

Answer 17

• Factor IX

Question 18

what are normal levels of factors VIII & IX

Answer 18

• 50-150%

Question 19

what are the levels of factors VIII & IX at different stages of haemophilia

Answer 19

• mild: 6-50%
• moderate: 1-5%
• severe: <1%

Question 20

what are the consequences of haemophilia

Answer 20

• bruising

- joint bleeding & destruction

Question 21

how is clotting time restored

Answer 21

• mixing with normal plasma

- replacement of VIII

Question 22

what factor affect PT (prothrombin)

Answer 22

Factor VII

Question 23

what factors affect APTT (Activated partial thermoplastin time)

Answer 23

• factor XII
• factor PK
• factor XI
• factor IX
• factor VIII

Question 24

what factors affect TT (thrombin time)

Answer 24

• factor X
• factor V
• factor II
• factor I