Anticoagulants

Question 0

What is an embolus?

Answer 0

A clot that is free and flowing through the vessel

Question 1

What is a thrombus?

Answer 1

a clot that is attached to a vessel wall

Question 2

What are thrombi composed of?

Answer 2

platelet aggregates
fibrin
trapped blood cells

Question 3

Which type of anti-thrombotic agents disrupt the coagulation cascade?

Answer 3

anticoagulants

Question 4

Which type of anti-thrombotic agents inhibit aggregation and activation platelets?

Answer 4

anti-platelets

Question 5

Which type of anti-thrombotic agents degrade clots?

Answer 5

Fibrinolytic Agents

Question 6

What do anticoagulants, anti-platelets & fibrinolytic agents all have in common?

Answer 6

They all increase the risk of bleeding

Question 7

The more potent the anti-thrombotic agent, the __________ the risk of bleeding.
A. Higher
B. Lower

Answer 7

A. higher

Question 8

What is thrombosis?

Answer 8

alterations that favor coagulation

Question 9

What are the 2 MOA’s of anticoagulants?

Answer 9

1. inhibit the function of coagulation factors, directly or indirectly (activating anti-clotting factors)
2. interfere with the synthesis of coagulation factors

Question 10

What are 3 parenteral anticoagulants?

Answer 10

unfractionated heparin (UFH)
low molecular weight heparin (LMWH)
Fondaparinux (Arixtra®)

Question 11

What is the MOA of parenteral anticoagulants?

Answer 11

they bind to and enhance the action of antithrombin

(they indirectly inhibit thrombin and factor Xa)

Question 12

List 3 LMWH drugs.

Answer 12

Enoxaparin (Levonox)
Dalterparin (Fragmin)
Tinzaparin (Innohep)

Question 13

What drug class is derived from chemical or enzymatic degradation of UFH into fragments that are about 1/3 the size of UFH?

Answer 13

LMWH (Low Molecular Weight Heparin)

Question 14

What is the average molecular weight of LMWH?

Answer 14

4500-5000

Question 15

True or false. NSAIDs + oral anticoagulant increase bleeding risk.

Answer 15

True

Question 16

[SATA] Rivaroxaban is a \_\_\_\_\_\_\_\_ substrate. 
A. 3A5
B. Pgp
C. OATP
D. 2C9
E. 3A5

Answer 16

A, B, E

Question 18

How is Rivaroxaban eliminated?

Answer 18

Renal and hepatic (3A4, 3A5, Pgp substrate)

Question 19

SATA: Use with caution in liver and kidney impairment.
A. Rivaroxaban
B. Apixaban
C. Dabigatran

Answer 19

A, B,

C (just kidney)

Question 20

Which oral anticoagulant is NOT a direct factor Xa inhibitor?

Answer 20

Dabigatran (direct thrombin inhibitor)

Question 21

How is apixaban (Eliquis) eliminated?

Answer 21

renal and hepatic (3A & Pgp substrate)

metabolite is eliminated in urine and bile

Question 22

Which oral anticoagulant is dosed QD?

Answer 22

rivaroxaban (Xarelto)

Question 23

Which oral anticoagulant has an adverse effect of dyspepsia?

Answer 23

Dabigatran (Pradaxa)

Food, H2 blockers or PPIs may help

Question 24

How is Dabigatran eliminated?

Answer 24

10% glucuronidated into active metabolite

80% eliminated in urine

Question 25

Which oral anticoagulant is a prodrug?

Answer 25

Dabigatran

Question 26

Adverse effects of UFH?

Answer 26

Bleeding Thrombocytopenia (HIT) hypersensitivity reaction Long term use: osteoporosis & fractures, decreased effectiveness

Question 27

What is the antidote for UFH?

Answer 27

protamine 1%

Question 28

Counseling points for Rivaroxiban (Xarelto)?

Answer 28

take with LARGEST meal of the day

Question 29

Which anticoagulants have an increased risk of epidural or spinal hematoma when receiving spinal puncture or anesthesia and this anticoagulant?

Answer 29

LMWH Rivaroxaban Dabigatran

Question 30

``` [SATA] Apixaban is a ________ substrate. A. 3A B. Pgp C. OATP D. 2C8 ```

Answer 30

A, B

Question 31

True or False. Dabigatran is MOSTLY RENALLY cleared.

Answer 31

True (80%)

Question 32

Disadvantages of Oral anticoagulants?

Answer 32

``` EXPENSIVE no antidote no monitoring (hard to know if pt is compliant) Drug-drug interactions (CYPs, Pgp) ```

Question 33

Advantages of Oral anticoagulants?

Answer 33

Oral, more consistent dosing, no monitoring