Anticoagulation (1*)

Question 1

Heparins:
Unfractionated Heparin - What is it used for?
→ How does it work?
→ What is its benefit?
→ Does it require monitoring?

LMWH - What is it used for?
→ How does it work?
→ Does it require monitoring?
→ What are some examples?

What are the SEs of Heparins?

What can be used to reverse the effects of Heparin?

Answer 1

➊ Therapeutic anticoagulation peri-operatively, or if significant bleeding risk
→ Activates Antithrombin
→ Works very quickly and has a very short-half life, allowing it to provide interim anticoagulation
→ Yes as it consists of a variety of chain lengths, so its effects are less predictable

➋ VTE prophylaxis and treatment
→ Inactivates Factor Xa
→ No as it only consists of short-chain heparins, so its effects are more predictable
→ Dalteparin, Enoxaparin

➌ Bleeding, Heparin-induced Thrombocytopenia (HIT)

➍ Protamine Sulphate

Question 2

Warfarin:
What’s it used for?

How does it work?

What is used to monitor its effects?

What are its CIs?

Answer 2

➊ Long-term anticoagulation

➋ Reduced production of Vit K-dependant clotting factors (2, 7, 9, 10)

N.B. A good way of remembering these factors is “1972”.

➌ INR

➍ Bleeding disorders, Peptic ulcer, Pregnancy (teratogen)

N.B. Important to note that warfarin is initiallyprothrombotic. So, when initiating, pts are usually bridged with a LMWH for 5 days.

Question 3

DOACs:
What are some examples?

How do they work?

Does it require monitoring?

Answer 3

➊ Rivaroxaban, Apixaban, Dabigatran

➋ • Rivaroxaban, Apixaban - Factor Xa inhibitors
• Dabigatran - direct Thrombin inhibitor

➌ No