VTE TBL Flashcards
What drives arterial clots and venous clots, and their respective treatments?
Arterial: platelets (use antiplatelet)
Venous: fibrin (use anticoag)
Arterial clots may lead to
(hint; most important places to deliver oxygenated blood)
Myocardial infarction
Stroke
Venous clots may lead to
a venous thromboembolism:
Deep Vein Thrombosis
Pulmonary Embolism
What is Virchow’s Triad?
Describes main drivers of clot formation
1. hypercoagulable state (body primed to form clot; cancer, pregnancy, estrogen tx)
2. venous stasis (pooling blood; in legs during immobility)
3. endothelial injury (trauma, surgery)
List risk factors for VTE.
- Virchow’s triad
- prior VTE
- age > 40
Major transient risk factors
- surgery w/ general anesthesia for 30+ mins
- confined to hospital bed for 3+ days w/ acute illness
- C-section
Minor transient risk factors
- surgery w/ general anesthesia for <30 mins
- in hospital <3 days w/ acute illness
- estrogen tx
- pregnancy and peurperium (6 weeks after pregnancy)
- confined to bed 3+ days
- decreases mobility for 3+ days
Persistent risk factors
- active cancer
- inflammatory bowel dx
- autoimmune dx
- chronic infections
- chronic immobility
Common drug-drug interactions of ACs (due to increased bleeding risk)
- anticoagulants
- antiplatelets
- NSAIDs
- SSRIs/SNRIs
Heparin dosing for VTE prophylaxis
5000 units subQ q8-12h
Heparin dosing for VTE treatment
- IV bolus: 80u/kg
- initial IV infusion: 18u/kg/hr
(no renal adjustment needed)
Enoxaparin dosing for VTE prophylaxis
- 40 mg subQ daily
- 30 mg subQ BID
if CrCl <30mL/min; 30 mg subQ daily
Enoxaparin dosing for VTE treatment
- 1.5 mg/kg subQ daily
- 1 mg/kg subQ q12h
if CrCl <30 mL/min; 1mg/kg subQ daily
Special monitoring parameters for LMWH (enoxaparin)
- SCr
- peak anti-Xa levels (special pops only)
If patient has a history of HIT
d/c UFH/LMWH
=> start factor Xa inhibitor “fondaparinux” (Arixtra)
*CI if CrCL < 30 mL/min
