Summary of the key points with NOACS and anticoagulation, which is likely to present in context of Atrial Fibrillation, Stroke, MI, any cause of thrombosis and embolism. This is all high yield as direct list questions and core knowledge that is highly likely to be assessed.
HASBLED
- H = HTN > 160
- A= abnormal liver or renal (Cirrhosis or Bilirubin 2 x normal, ALT/AST/ALP (all) 3 x upper limit normal. Creatine > 200 or Dialysis or transplant
- S = stroke
- B = bleeding history or predisposition
- L = labile INR (< 6 of 10 in range)
- E = elderly
- D = drugs (anti-platelets, alcohol, NSAIDs) (Alcohol more than 8 drinks per week, NAISDs use or prednisone.
ABCD2 risk TIA
- A = Age > 60 (1)
- B = BP > 140/90 (1)
- C = clinical features (unilateral limb weakness (2) speech impairment (1)
- D = duration > 60 min (2); 10 -60 min (1)
- D = diabetes (1)
Advantages of NOACs
- Fixed dosing
- Lack of required monitoring
- Fast onset
- Fast offset
- Fewer drug and food interactions
What are the classes of NOACs? List 2
- Factor Xa – Rivaroxaban – once daily
- Thrombin – Dabigatran – has reversal agent – twice daily
What are the TGA approved indications for NOACs
- Non-valvular AF and at least one additional risk factor for stroke
- Check thuis
What are the disadvantages of NOACs
- May be effected in hyperthyroidism – no data but likely to be less affective needing a higher dose
- Antidotes to only dabigatran – but expensive and not easily available in Australia
- Used cautiously in renal disease
- Contraindicated in renal failure
What are the 3 NOACs available in Australia? List 3
- Rivaroxaban
- Dabigatran
- Apixaban
What are the indications for all NOACs?
- VTE prophylaxis in non valvular AF
- Elective knee replacement surgery – DVT prophylaxis on this context
What is the only NOAC approved for DVT and PE?
- Rivaroxaban
Which NOAC has an antidote?
- Dabigatran
- Its called Praxbind
What are the drug-drug interactions of Rivaroxaban? List 2
- Azoles
- HIV protease inhibitors
What is the relative risks of warfarin vs NOACs – list 1
- GI bleeding more with NOACs than warfarin
When would you elect warfarin over NOACs?
- Prosthetic valves
- Valvular AF
- GI bleed
- High HASBLED score
- Renal impairment
Do you stop NOACs prior to procedures?
- Depends on risk benefit
How long before procedures do you stop NOACs?
- Warfarin stopped 5 days before surgery
- Bridging with LMWH or UF heparin
- Rivaroxaban stopped 1-2 days before
- Aspirin stopped 5-7 days before surgery
- Clopidogrel stopped 5-7 days before
When do you restart anticoagulation after surgery?
- High risk would be 2-3 days
Immediate management of GI bleeding on NOACs
- Use Praxbind for Dabigatran
- Supportive management with haemodynamic resuscitation
- Cease NOAC
- Haemostatic measures
Non-pharmacological approaches to stopping AF
- AV node ablation with permanent ventricular pacing
How do you switch from warfarin to NOAC?
- You start when INR < 2
- You just start it
