Pharmacology: Haemostasis

Question 1

haemostasis

Answer 1

arrest of blood loss from a damaged vessels

Question 2

stages in haemostasis

Answer 2

1. vascular damage exposes collagen and TF
2. vasoconstriction, platelet adhesion and aggregation by fibrinogen
3. formation of clot by TXA2 and ADP with P2Y12

Question 3

what are anticoagulants used in?

Answer 3

venous thrombosis and embolism (DVT, post-op, artificial heart valves and AF)

Question 4

what do all anticoagulants carry a risk of?

Answer 4

haemorrhage

Question 5

mechanism of action of warfarin

Answer 5

renders factors II, VII, IX and X inactive

Question 6

how is an overdose of warfarin treated with?

Answer 6

phytomenadione

Question 7

factors that increase warfarin action

Answer 7

• liver disease
• metabolic rate
• NSAIDS

Question 8

factors that lessen the action of warfarin

Answer 8

• pregnancy

- vitamin K consumption

Question 9

mechanism of action of heparin

Answer 9

binds to antithrombin III which inhibits Xa and IIa

Question 10

examples of LWMHs

Answer 10

enoxaparin

dalteparin

Question 11

mechanism of action of LMWHs

Answer 11

inhibits Xa not IIa

Question 12

adverse of heparin and LMWHs

Answer 12

osteoporosis
hypoaldosteronism
hypersensitivity

Question 13

orally active inhibitors

Answer 13

dabigatran etexilate

rivaroxaban

Question 14

when are antiplatelets used

Answer 14

arterial thrombosis

Question 15

four types of anticoagulation

Answer 15

• warfarin
• heparin
• LMWHs
• orally active inhibitors

Question 16

three types of antiplatelets

Answer 16

• asprin
• clopidogrel
• tirofiban

Question 17

mechanism of action of aspirin

Answer 17

blocks COX in platelets

Question 18

adverse of aspirin

Answer 18

GI bleeding and ulceration

Question 19

mechanism of action of clopidogrel

Answer 19

links to P2Y12 receptors

Question 20

when is clopidogrel used

Answer 20

if intolerance to aspirin

Question 21

when is tirofiban used

Answer 21

prevent MI for patients with stable angina

Question 22

what are fibrinolytics used used for?

Answer 22

reopen arteries following MI and stroke

Question 23

two types of fibrinolytics

Answer 23

1. streptokinase

2. alteplase and duteplase

Question 24

what is streptokinase

Answer 24

protein extracted from streptococci (action blocked after 4 days due to generation of antibodies)

Question 25

adverse of streptokinase

Answer 25

can cause allergic reaction

Question 26

what are alteplase and duteplase

Answer 26

recombinant tissue plasminogen activator

Question 27

two types of diuretics

Answer 27

• thiazide

- loop

Question 28

example of a thiazide diuretic

Answer 28

bendoflumethiazide

Question 29

example of a loop diuretic

Answer 29

furosemide

Question 30

adverse of diuretics

Answer 30

diabetes exacerbation
gout exacerbation
hyperaldosteronism
hypokalaemia
enlarged prostate (urinary retention)

Question 31

what is fondaparinux?

Answer 31

anticoagulant Xa inhibitor

Question 32

which drug is the anticoagulant of choice for mechanical valves?

Answer 32

warfarin