Other Anti-coags Flashcards
Factor Xa inhibitors (oral), MOA
- Rivaroxaban
- Edoxaban
- Apixaban
-MOA: oral direct factor Xa inhibitor (inhibits free and clot-bound factor Xa)
Clinical indications of factor Xa
- Prevention of VTE in pts undergoing THA/TKA (tx for at least 10-14d, preferably 35d)
- Prevention of stroke/systemic embolism in pts with non-valvular AF
- Prevention and tx of VTE
Clinical indication for Rivaroxaban
PAD
When should you start the oral factor Xa inhibitors? How’s the bleeding risk?
- Start after surgery
- Bleeding risk LESS than warfarin (apixaban has the least)
What is the reversal agent for the oral Xa inhibitors?
Andexanet-alpha
Drug interactions for oral Xa inhibitors
- Most are substrates of P-GP and 3A4
- Don’t use with other anticoags
LMWH drug and MOA
- Enoxaparin
- MOA: antithrombin mediated inhibition of factors Xa > IIa
LMWH clinical indications
-DVT prophylaxis of hip/knee/abd sxs, restricted mobility
-DVT/PE tx
-ACS
(use this unless you can’t, lots of advantages)
What is a limitation of LMWH?
Harder to dose in CKD and obese pts
Drug monitoring for LMWH
- Monitor for anemia/signs of bleeding (H/H)
- No anticoag monitoring necessary, best during tx rather than prophylaxis
What is the reversal agent for LMWH?
Protamine sulfate
Common ADRs of LMWH
- Injection site pain and hematoma
- Hemorrhage less than UFH
- Thrombocytopenia < UFH
- HIT rarely (<1%)
Synthetic analog of Heparin, MOA
Fondaparinux, anti-thrombin mediated inhibition of factor Xa
Clinical indications of Fondaparinux
- DVT prophylaxis of hip/knee/abd sxs
- VTE tx
What is a unique advantage of Fondaparinux?
Long half life (qd dosing)
What is the drug monitoring, drug interactions, and ADRs to be aware of in Fondaparinux?
- Monitor: H/H, SCr, anti-Xa assay
- Interactions: other antiplatelets/anticoags/NSAIDs -> bleeding
- ADRs: hemorrhage
What are the direct thrombin inhibitors (oral, IV)
- Oral: Dabigatran
- IV: Argatroban, Bivalirudin
MOA of Dabigatran
Synthetic, non-peptide, direct thrombin (IIa) inhibitor, inhibits both clot bound and circulating thrombin -> decreases thrombin-stimulated platelet aggregation
Clinical indications of Dabigatran
- Prevention of stroke in pts with non-valvular AF
- Prevention of VTE in pts undergoing THA/TKA
- VTE tx (not initial)
What is the reversal agent for Dabigatran?
Idarucizumab
What is a unique pearl about the storage of Dabigatran?
Sensitive to moisture, should be kept in original bottle and tightly capped
Dabigatran + __________ = increase hemorrhage
Simvastatin
ADRs of Dabigatran
- Bleeding
- Dyspepsia/gastritis
What is the only approved product for pts with HIT?
Argatroban
Argatroban has a very short half life and is safest in a patient with what?
CKD, metabolized by the liver
Bivalirudin pearls
- Approved for ACS managed with PCI
- Pts with/at risk of HIT undergoing PCI
- Cannot reverse
Old fibrinolytics
- Streptokinase
- Urokinase
Older fibrinolytic, MOA
- Alteplase aka recombinant tissue-type plasminogen activator (tPA)
- MOA: initiates local fibrinolysis by binding to fibrin in a thrombus, converts entrapped plasminogen to plasmin
Clinical indications of alteplase
- STEMI
- Acute pulm embolism
- Acute ischemic stroke
- Central venous cath clearance
- Acute peripheral arterial occlusive disease
Newer fibrinolytic, MOA
- Tenecteplase
- 14x more fibrin specific
- MOA: same as alteplase with longer half life (single IV bolus)
Clinical indications of Tenecteplase
STEMI
Warfarin, UFH, LMWH in pregnancy
- Warfarin: crosses placenta, teratogenic
- UFH: cat C (no known teratogenecity, does not cross placenta)
- LMWH: enoxaparin is cat B for VTE
Warfarin embryopathy is characterized by:
- Midface hypoplasia
- Stippled chondral calcification
- Scoliosis
- Short proximal limbs/phalanges
