VTE - Treatments

Question 1

Dabigatran
- Dosing

Answer 1

5-10 days of parenteral treatment

Then 150 mg BID

Question 2

Dabigatran
- Antidode

Answer 2

Idarucizumab

Question 3

Edoxaban
- Dosing

Answer 3

5-10 days of parenteral treatment

60 mg daily

Reduce to 30 mg daily if:
- CrCl below 50
- Body Weight below 60 kg
- P-gp inhibitor

Question 4

Apixaban
- Dosing

Answer 4

10 mg BID for 7 days
then 5 mg BID

Question 5

Rivaroxaban
- Dosing

Answer 5

15 mg BID for 3 weeks
then 20 mg daily (With Food)

Question 6

Apixaban
- Antidote

Answer 6

Andexanet Alfa

Question 7

Rivaroxaban
- Antidote

Answer 7

Andexanet Alfa

Question 8

DOAC Drug Interactions

Answer 8

Dabigatran and Edoxaban
- P-Glycoproteins

Apixaban and Rivaroxaban
- P-Glycoproteins and CYP-3A4

Question 9

P-gp inhibitors

Answer 9

Increases DOAC levels = Increases bleeding
- Azoles
- Ritonavir

Question 10

P-gp inducers

Answer 10

Decreases DOAC levels = Increases Clotting
- Rifampin
- Carbamazepine
- Phenytoin
- St Johns Wort (As well as CYP 3A4)

Question 11

SSRI and St Johns Wort

Answer 11

SSRI are safe

Question 12

Ritonavir

Answer 12

High Clot RIsk:
- Hold DOAC, start LMWH

Low Clot Risk:
- Hold DOAC, start ASA

Stop Rivaroxaban

Question 13

INR Target

Answer 13

INR without warfarin
- 1.0

INR with warfarin
- 2.0 - 3.0

INR range for VTE
- 2.0 - 3.0

Question 14

Warfarin Initiation

Answer 14

Initiate
- 5 mg for 2 days

Check INR on Day 3 and Day 6:
- Mon / Thurs
- Tues / Fri

Question 15

Warfarin Adjustment

Answer 15

At Initiation warfarin is not at steady state, make changes now before it gets worse

INR > 1.6 = Reduce Dose
INR < 1.2 = May need higher dose

Question 16

Warfarin Maintenance

Answer 16

When INRs are not fluctuating as much

Question 17

Warfarin Adjustment Guidelines
- Increase Dose

Answer 17

<1.5
- Reload a dose is up to x2 of the daily dose
- Increase weekly dose by 5-15%

1.5 - 1.9
- Reload a dose up to daily dose
- Increase weekly dose by 0-10%

Question 18

Warfarin Adjustment Guidelines
- Decrease Dose

Answer 18

3.1 - 3.5
- Hold a dose up to daily
- Decrease weekly dose by 0-10%

3.6 - 5.0
- Hold a dose up to x2 daily dose
- Decrease weekly dose by 5-15%

> 5.0
- Hold warfarin
- Initiate Vit K 1-2.5 mg

> 9.0
- Hold warfarin
- Initiate Vit K 2-5 mg

Question 19

Factors that impact INR

Answer 19

• Changes to Health
• Changes to Medications
• Changes to Lifestyle

Question 20

Diarrhea affect INR

Answer 20

Vitamin K is lost = Increases INR
- More chance to bleed

Question 21

Exacerbations of Heart Failure

Answer 21

Slow warfarin metabolism = Increases INR
- More chance to bleed

Question 22

Hypothyroidism

Answer 22

Slow down clotting factor break down
= Decreases INR
- More chance to clot

Question 23

Alcohol Consumption

Answer 23

Increases INR
= More chance to bleed

Question 24

Level of Activity

Answer 24

Decreases INR
- More chance to clot