IC5 SPAF

Question 1

Dabigatran: when to decr dose from 150mg BD to 110mg BD ?

Answer 1

Any of following:
- ≥ 80y/o
- use of PGP inhibitors
- high bleeding risk

Question 2

Apixaban: when to decr dose from 5mg BD to 2.5mg BD?

Answer 2

Any 2 of following:
- ≥ 80y/o
- ≤ 60kg
- Scr ≥ 1.5mg/dL or 132.6mmol/L

OR CrCl 15-29ml/min

Question 3

Normal BW in DOAC

Answer 3

60-120kg

Question 4

4 key reasons why DOACs are preferred over warfarin

Answer 4

1. Ease of dosing, no need titration
2. No need tight monitoring
3. Significantly lesser DDI
4. Less major bleeding

Question 5

Which agent to give when loading warfarin?

Answer 5

Enoxaparin (LMWH)

Question 6

Which clotting factor is not included in INR?

Answer 6

IX (9)

Question 6

Which clotting factor plummets the fastest upon warfarin initiation?

Answer 6

factor VII (7)

Question 7

PGx-related enzymes for warfarin

Answer 7

VKOR, 2C9 polymorphisms

Question 8

Locally, which population require higher mean daily dose (VKORC1) for warfarin?

Answer 8

Indians

Question 9

When would PGx for warfarin be beneficial?

Answer 9

Beneficial for those requiring ≤21mg/week or ≥49mg/week

Question 10

When to adjust warfarin dose pre-emptively?

Answer 10

• Bactrim (Sulfamethoxazole / Trimethoprim)
• Ciprofloxacin

Question 11

When is warfarin still needed

Answer 11

• Left Ventricular Thrombus
• Prosthetic -Heart Valve
• Antiphospholipid Syndrome-related VTEs

Question 12

Impact of Alcohol Binge on INR and why

Answer 12

Incr INR; CYP450 enz inhibition

Question 13

INR can be raised in febrile states because of the _______

Answer 13

increased turnover of clotting factors

Question 14

Antibiotics that do not need dose adj for warfarin

Answer 14

• Macrolide
• Augmentin
• Doxycycline

Question 15

Impact of Chronic alcoholism on INR and why

Answer 15

Decr INR; CYP450 enz induction -> incr warfarin metabolism

Question 16

Impact of sudden incr in physical activity on INR and why

Answer 16

Decr INR; incr warfarin metabolism

Question 17

Impact of smoking on INR and why

Answer 17

Decr INR; CYP450 enz induction -> incr warfarin metabolism

Question 18

Impact of fluid retention (gut) on INR

Answer 18

Decr INR

Question 19

Impact of fluid retention (liver) on INR

Answer 19

Incr INR

Question 20

Impact of hyperthyroidism on INR and why

Answer 20

Incr INR; Hyperthyroidism increases clotting factor turnover