Anticoagulants

Question 1

Anticoagulants

Answer 1

Unfractionated Heparin (UFH)
LMWH
Rivaroxaban (Xarelto), Apixaban (Eliquis)
Direct thrombin inhibitors (DTIs)
Warfarin (Coumadin)

Question 2

Heparin (Unfractionated Heparin) - MOA

Answer 2

Inactivates thrombin and factor Xa
- inhibits fibrin formation
Doesn’t dissolve existing blood clots

Question 3

Heparin (Unfractionated Heparin) - Indications and SE

Answer 3

1. Drug of choice in acute DVT, PE
2. To prevent new thrombus formation and embolization

SE - bleeding, HIT (heparin induced thrombocytopenia)

Question 4

About Heparin - how’s it administered?

what needs to be monitored?

Answer 4

Large, so cannot be absorbed if given orally = IV drip, SQ
Rapid onset, short duration = 1/2 life: 1.5 hr
Does not cross placenta
Need to monitor PTT (partial thrombin time) level
(60 - 80 sec)
Need to monitor platelet counts

Question 5

PTT levels for heparin

Answer 5

levels should be 60-80 sec.
if 45 - ⇡ rate == risk of clotting
if 90 - ↓ rate == risk of bleeding

⇡ ↓

Question 6

Why give heparin?

Answer 6

• prophylaxis for pt on bedrest (prevent clots)
• for acute thromboembolitic disorders (chest pain)
  ==> titrate to achieve PPT rate 60-80 sec
• central line catheter (PICC) flush
• reversal agent: protamine sulfate

Question 7

what is HIT?

Answer 7

heparin induced thrombocytopenia
= an immune (antibody) medicated allergic reaction => causes platelet aggregation ==> see:
- ↓ in platelet counts
- thrombosis (clot) in small arteries

Platelet count < 100,000 or 50% ↓ from baseline (between 5-14 days after start of heparin therapy)