Anticoagulant drugs

Question 1

Outline the coagulation cascade

Answer 1

Question 2

What is another name for thrombin?

Answer 2

Activated factor II

Question 3

What are the multiple pro-coagulative functions of thrombin?

Answer 3

Question 4

Give examples of direct factor inhibitors

Answer 4

Direct thrombin inhibitors
Direct factor Xa inhibitors

Question 5

Function of direct thrombin inhibitors

Answer 5

Bind thrombin in circulation and already attached to a clot

Question 6

Function of factor Xa inhibitor

Answer 6

Greater effect on anticoagulation. Higher in the coagulation cascade

Question 7

Lab parameters of direct thrombin inhibitors

Answer 7

Prolongs thrombin
Less effect on PT and aPTT

Question 8

Lab parameters of factor Xa inhibitor

Answer 8

Prolongs PT and aPTT
No effect on thrombin

Question 9

Direct thrombin inhibitors are especially useful when heparin causes an adverse reaction called..

Answer 9

HIT, or heparin induced thrombocytopenia

Question 10

Side effects of direct thrombin inhibitors

Answer 10

GI symptoms like dyspepsia and gastritis
Bleeding when taken in excess

Question 11

Direct thrombin inhibitors should not be discontinued suddenly as it leads to…

Answer 11

Increased thrombosis and risk of strokes

Question 12

Give examples of direct thrombin inhibitors

Answer 12

Dabigatran etexilate and dabigatran

Question 13

Give examples of direct factor Xa inhibitors

Answer 13

Apixaban, edoxaban and rivaroxaban

Question 14

Side effects of direct factor Xa inhibitors

Answer 14

Bleeding

Question 15

When are direct thrombin inhibitors used?

Answer 15

Replacement of heparin in HIT

Question 16

When are direct factor Xa inhibitors used?

Answer 16

Alternative to Warfarin

Question 17

Differentiate between unfractionated and fractionated heparin

Answer 17

Un: HMWH + LMWH
Frac: LMWH

Question 18

Only LMWH/HMWH have an effect on thrombin

Answer 18

HMWH - in order to increase antithrombin III’s activity against thrombin, the thrombin needs to bind to the long tail of the heparin

Question 19

What is used to measure the efficacy of heparin?

Answer 19

aPTT - longe than average

Question 20

If heparin aPTT is greater than 100 then the patient must be suffering from..

Answer 20

Internal bleeding

Question 21

Antithrombin also binds to active ________, which is a pivotal coagulation protein that converts ________ into ________

Answer 21

Antithrombin also binds to active factor X, which is a pivotal coagulation protein that converts prothrombin into thrombin

Question 22

Function of heparin

Answer 22

Decreases activity of clotting factors thrombin and Xa by binding to antithrombin 3 and increasing its activity

Question 23

Unfractioned heparin inhibits..

Answer 23

Factor Xa & thrombin

Question 24

Fractioned heparin inhibits..

Answer 24

Factor Xa

Question 25

Producing coagulation factors ____________ requires an enzyme that uses vitamin K

Answer 25

II, VII, IX, and X

Question 26

Function of Warfarin

Answer 26

Blocks vitamin K from getting recycled and as a result factors II, VII, IX, and X don’t get activated

Question 27

How is PT measures?

Answer 27

Using INR

Question 28

Warfarin prevents disorders that cause blood clots. Give examples of this

Answer 28

DVT
Prosthetic heart valves
A-fib

Question 29

T or F: Warfarin is C.I in pregnancy

Answer 29

True

Question 30

What does warfarin inhibit?

Answer 30

Protein C and S
II, VII, IX, X

Question 31

Heparin enhances the activity of another anticoagulation protein found in the body called..

Answer 31

Antithrombin III

Question 32

Answer 32

Question 33

Side effects of heparin

Answer 33

Bleeding
HIT
Osteoporosis

Question 34

Monitoring of heparin

Answer 34

APTT for unfractioned
Usually no monitoring for LMWH

Question 35

Reversal for heparin

Answer 35

Stop the heparin

If severe bleeding:
Protamine sulphate- reverses antithrombin effect
Complete reversal for unfractionated
Partial reversal for LMWH

Question 36

Where is vitamin K absorbed?

Answer 36

Upper intestine - bile salts for absorption

Question 37

Where is vitamin K synthesised?

Answer 37

Liver

Question 38

Warfarin reversal

Answer 38

Question 39

Answer 39

Question 40

Label where Heparin acts

Answer 40

Question 41

Label where Warfarin acts

Answer 41

Question 42

Label where DOAs act

Answer 42