Anticoagulation I (Oral Antiplatelets/Anticoagulants) Flashcards
What is the function of fibrin and platelets?
Fibrin: mesh-like network to trap cells in the blood clot
Platelets: adds mass to the thrombus & builds it up
How do anticoagulants work & what are some drug examples?
E.G. Warfarin, DOAC/NOAC’s, heparins
- They reduce clotting by decreasing fibrin/thrombus formation
How do antiplatelets work & what are some drug examples?
E.G. Clopidogrel, ticagrelor, aspirin
- They prevent platelet aggregation & a clot from forming
How do thrombolytics work & what are some drug examples?
E.G. Alteplase, streptokinase, tenecteplase
- They aid in the breakdown of clots
How does aspirin work as an antiplatelet?
Aspirin prevents the COX-1 enzyme, which prevents AA acid –>TXA2, so platelets are not activated.
What drugs are factor Xa inhibitors?
Rivaroxiban, apixaban, edoxaban
What drug is a thrombin inhibitor?
Dabigatran
In what circumstances do we use antiplatelets?
- Treatment of ACS (dual antiplatelet therapy)
- Long term stroke prevention (not from AF)
- Secondary prevention of NSTEMI, STEMI, & UA
In what circumstances do we use warfarin?
- Patients with mechanical heart valves
- Thrombotic conditions
- Patients who need a higher INR range
What is the INR range used for & what is the ideal target range for someone taking warfarin?
It is used to measure the prothrombin time of a patient taking warfarin.
Ideal range should be 2-3 if taking warfarin.
High INR (>3): High risk of bleeding Low INR (<2): Thrombosis risk, e.g. stroke, DVT/PE
What must always be present on a patient taking blood-thinning medications?
An alert card.
Why does warfarin have many drug/food interactions?
Because it is metabolised by CYP450, which can also metabolise some drugs/food.
How can you ensure that a patient taking anticoagulants can reduce their chance of bleeding?
- Control their BP
- Reduce alcohol intake
- Consider PPI/H2RA
- Review pros/cons for them taking the antiplatelet
- Review NSAID, SSRI, & steroid use
