Warfarin

Question 1

Why does warfarin cause a transient increase in clotting risk when it is started?

Answer 1

Warfarin also reduces protein C and protein S production

protein c and s are anti-coagulants

Question 2

How to mitigate the transient increased clotting risk when pts start warfarin

Answer 2

Give heparin to cover the starting period

(note this is done in primary care)

Question 3

INR in mechanical aortic valve

Answer 3

3

this A-OR-TIC has 3 syllables so INR is 3

((aortic valve has higher pressures and flow rate so therefore thrombus less likely in aortic mechanical valve than mitral mechanical valve))

Question 4

INR in mechanical mitral valve

Answer 4

3.5

Mitral MEGA = higher than mechanical aortic INR

Question 5

INR in VTE prophylaxis
(1st VTE and recurrent VTE)

Answer 5

2.5 first
3.5 recurrent

Question 6

AF target INR

Answer 6

2.5

Question 7

Indications for warfarin

Answer 7

Mechanical heart valves is the only indication where warfarin is 1st line

can be used in VTE prophylaxis and AF if DOACs cant be used

Question 8

pt on warfarin and they are having major haemorrhage.. what do you do?

(dosent matter what INR is)

Answer 8

Stop warf

give vit k (5mg IV)

prothrombin complex concentrate (FFP 2nd line)

Question 9

what are the different levels of high INR management

Answer 9

major bleeding (no matter the INR) - high dose IV vit k (5mg). hold warfarin and give PCC

no bleeding INR >8 oral vit K and hold warf till INR,5
minor bleeding INR>8 IV Vit K and hold till INR <5

no bleeding INR 5-8- hold 1-2 doses
minor bleeding INR 5-8- IV Vit K and hold till INR <5