haemostasis aquired disorders

Question 1

aquired vascualr bleeding disorders

Answer 1

• senile purpura
• scurvy (vit C deficiency)
• steroid purpura

Question 2

senile puprora

Answer 2

• collagen reduces, more likely to bruise

- do not bleed excessively after procedures

Question 3

causes of thrombocytopenia

Answer 3

failure of platelet production
increased consumption of platelets
hypersplenism

Question 4

failure of platelet production causes

Answer 4

• vitamin B12 or folate deficiency
• bone marrow infiltration (leukaemia or metastases)
• radiation, cytotoxic therapy

Question 5

increased consumption of platelet causes

Answer 5

• immune thrombocytopenia (ITP)
• disseminated intravascular coagulation
• HIV infection

Question 6

immune thrombocytopenai

Answer 6

children usually follows acte infection

adults cause usually unclear

Question 7

treatments for thrombocytopenia

Answer 7

• steroids
• intravenous immunoglobulin
• splenectomy
• thrombopoietin receptor analogues

Question 8

disseminated intravascualr coagulation

Answer 8

breakdown of haemosttic balance

- simultaneous bleeding and microvascular thrombosis

Question 9

causes and treatment of disseminated intravascualr coagulation

Answer 9

sepsis
obsteric
malignancy

• remove underlying cause
• give plasma and platelets if bleeding once cause removed

Question 10

splenomegaly hypersplenism

Answer 10

more platlets found in the spleen

Question 11

platelet function abnormalities aquired diseases

Answer 11

• antiplatelet drugs
• renal disease
• liver disease
• DIC

Question 12

antiplatlet drugs

Answer 12

asprin
clopidogrel
prasugrel

Question 13

asprin how it works

Answer 13

• inhibits cyclo-oxygenase (platelet enzyme) irreversibly

- act for a lifetime of platelet i.e. 7-10 days

Question 14

how does clopidogrel work

Answer 14

• blocks ADP receptor (or platelet surface) irreversibly

- acts for a lifetime of platelet i.e. 7-10 days

Question 15

how does prasugrel work

Answer 15

• blocks ADP receptor irreversibly
• acts for a lifetime of platelet i.e. 7-10 days
• more rapid and consistent inhibition than clopidogrel

Question 16

renal disease types

Answer 16

1) increased bleeding
- anaemia
- thrombocytopenia in autoimmune renal disease
- uraemia
- treat with DDAVP and or dialysis
2) increased thrombotic risk
- in nephrotic syndrome (Acquired antithrombin deficiency)

Question 17

what is the liver the site of

Answer 17

synthesis of coagluation facors and fibriongen

Question 18

what is liver disease associated with

Answer 18

bleeding and prolonged prothrombin time

Question 19

causes of bleeding with liver disease

Answer 19

1) reduced clotting factors
- due to poor synthesis or vit k deficiency
2) thrombocytopenia due to hypersplenism
3) platelet function defect
4) portal hypertension – bleeding from varices
5) dysfibrinogenemia
6) increased fribrino lysis

Question 20

what is vit K needed for

Answer 20

synthesis of coagulation factors 2, 7, 9 and 10

Question 21

what does vit k manifest as

Answer 21

prolonged prothrombin time

Question 22

drugs which cause acquired bleeding disorders

Answer 22

asprin (platelet fuction affected)
heparin (affect coagulation cascade)
warfarin
steroids

Question 23

thrombosis types

Answer 23

1) in arterial circulation (eg MI or stroke)
- high pressure system
- platelet rich
- treat with antiplatelet drigs
2) in venous circulation (eg DVT or PE)
- low pressure system
- fibrin rich
- treat with anticoagulant drugs

Question 24

antiplatlet drugs

Answer 24

1) asrpisin
2) clopidogrel
3) prasugrel
4) ticagrelor

Question 25

anticoagulants

Answer 25

1) intravenous
- unfractionated heparin
2) subcutaneous
- low molecular weight heparin
3) oral
- warfarin
- dabigatran, rivaroxaban, apixaban, edoxaban (direct oral antigoagualnts)

Question 26

Heparin

Answer 26

glycosaminolycan

• binds to antithrombin, increases its activity
• indirect thrombin inhibitor
• inactivates clotting factors, 2a, 10a, 9a ,11a

Question 27

low molecular weight heparin

Answer 27

smaller molecule made from heparin

• less variation in dose
• given subcutaneously
• renally excreted
• given once daily, weight adjusted dosing

Question 28

warfarin

Answer 28

• Inhibits production of factors 2,7,9,10

Question 29

monitoring warfarin

Answer 29

INR

Question 30

direct oral anticoagulants

Answer 30

• no monitoring

inhibits 10a

• aiming to replace heparin and warfarin
• standard dosing
• no alcohol/food interactions/few drug interactions
• short half life 10-15 hours
• more expensive than warfarin