VTE Prophylaxis / Anti-coagulants Flashcards
DVT prophylaxis?
Daily SC LMWH + TED stockings
Tx of DVT/PE?
Treatment dose LMWH + Warfarin or DOAC
Stop LMWH once INR in therapeutic range (2-3)
Tx duration = Min. 3 months
NOTE: Continue LMWH while starting Warfarin as warfarin inhibits Protein C/S as well, hence pro-coagulant in 1st few days
Heparin mechanism?
Potentiates Antithrombin III
This inactivates thrombin (F2) and F9/10/11
LMWH: route of admin + how do you monitor?
SC once daily
Doesn’t require monitoring EXCEPT pregnancy and renal failure. In these cases monitor using Anti-Xa levels
Unfractionated heparin: route of admin + how do you monitor?
IV loading dose then infusion Monitor APTT (or anti-Xa)
Antidote for heparin?
Protamine sulphate
Potential side effects of heparin?
Bleeding
Osteoporosis with long-term use
Heparin Induced Thrombocytopenia (HIP) - same features as HUS
Warfarin mechanism?
Inhibits enzyme responsible for regenerating active Vit K
Therefore inhibits synthesis of Factor 2, 7, 9, 10 + Protein C/S/Z
How do you monitor warfarin?
INR (= PT/10)
How do you reverse warfarin?
Prothrombin Complex Concentrate (Octaplex, Beriplex) - takes 30 mins
IV Vitamin K - takes 6hrs
Target INR for 1st episode DVT/PE?
2.5
Target INR for someone with AF?
2-3
Target INR for recurrent DVT/PE?
3.5
Target INR for mechanical prosthetic valve?
2.5-3.5
If INR is 5-8 with no bleeding what do you do?
Withhold few doses + Reduce maintenance dose
Restart when INR <5
