Anticoagulation Flashcards
Chapter 34 (2025)
What is the HAS-BLED score?
- Assesses the bleeding risk in patients that are needing anti-coag
- Needing anti-coag is based on CHADSVASc [stroke] when compared to HAS-BLED [bleed]
What is the dosing for Riveroxaban for Nonvalvular AFib [Stroke Prevention] and Treatment of DVT/PE [VTE]?
- Nonvalvular AFib [Stroke Prevention]: CrCl > 50 = 20mg PO QD; CrCl 15-50 = 15mg PO QD; CrCl < 15 = Avoid Use
- Treatment of DVT/PE [VTE]: 15mg PO BID x 21d, then 20mg PO daily WITH FOOD [CrCl < 30 = NO]
Missed dose: If 15mg BID… take Immediatly to equal 30mg/day; if 10, 15, 20mg QD… take immediatly
What is cardioversion and what are the anticoagluation treatments if someone where to undergo one?
- Cardioversion: trying to “reset” back to normal sinus rhythm
- Afib > 48h: Anti-coag for 3w prior to and 4w after
- Afib < 48h: Full anti-coag to start; cardioversion; then continue full anti-coag dose
What is the dosing for Enoxaparin for Prophyalxis of VTE, Treatment of VTE/UA/NSTEMI, and Treatment of STEMI?
- Prophylaxis of VTE: 30mg SubQ q12h or 40mg SubQ qd [CrCl < 30 = 30mg SubQ qd]
- Treatment of VTE/UA/NSTEMI: 1mg/kg SubQ q12h or 1.5mg/kg SubQ daily [inpatient only VTE] [CrCl < 30 = 1mg/kg SubQ qd]
- Treatment of STEMI: 30mg IV bolus + 1mg/kg SubQ, followed by 1mg/kg SubQ q12h [CrCl < 30 = 30mg IV bolus = 30mg IV bolus + 1mg/kg SubQ, followed by 1mg/kg SubQ qd]
What are the Black Box Warnings for Enoxaparin?
- Those getting neuraxial anesthesia or spinal puncture are at risk of Hematomas and Subsequent Paralysis
When HIT occurs, what are some things that we need to do?
- STOP all heparin/LMWH
- If on Warfarin; D/C and start Vit K [wait until platelets are < 150,000 before starting]
- Can give Argatorban [if Cardiac Srugery or PCI = Bivalirudin]
What are the Injectable Direct Thormbin Inhibitors and what are important to know about them?
- Argatroban and Bivalirudin
- Argatroban: used for those that have HIT or are undergoing PCI with high risk for HIT
- Bivalirudin: Used for those that are undergoing PCI with high risk of HIT
What drugs are those that inhibit Xa and AT and what are some important things to note about them?
- Xa and AT: Heparin [AT>Xa] and DOACs [Xa]
- AT [Anti-Thrombin] is the bodeis natural Anticoagulant which inhibits IIa [Thrombin] and Xa
Heparins and cause HIT
What are some key counseling points for Enoxaparin?
- Inject in right or left side of abdomin at least 2 inches away form belly button
- Pull off cap straight; DO NOT rid bubbles [unless doctor said too]; Hold syringe like a pencil & pinch the skin; Insert at straight up/down & press the plunger; Remove straight out
When using the CHADSVASc Scoring system, what are the recommendations from the score?
- 0 [Males] = NO Anti-coag
- 1 [Female] = NO Anti-coag
- 1 [Male] = Consider oral anti-coag
- 2 [Female] = Consider oral anti-coag
- >2 [Male] = Oral anti-coag; DOAC preferred
- >3 [Females] = Oral anti-coag; DOAC preferred
What is the way that we score someone using CHADSVASc?
- C: CHF = 1
- H: HTN = 1
- A: Age > 75 = 2
- D: Diabetes = 1
- S: Stroke Hx = 2
- V: Vascular Disease = 1
- A: Age 65-74 = 1
- Sc: Female = 1
What is the antidote for dabigatran and how is it dosed?
- Idarucizumab
- 5g IV [as 2 separte 2.5g doses 15 mins apart]
What is the dosing for Warfarin
- Healthy Outpatients: < 10mg PO QD
- Elderly/Malnurished: < 5mg PO QD
< 5mg PO QD falso for those that have other drugs that increase warfarin levels, have liver disease, Heart Failure or increase bleed risk
What is important to know about the dosing for edoxaban?
CrCl?
- CrCl > 95 = DO NOT USE
- CrCl 51-95 = 60mg PO daily
- CrCl 15-50 = 30mg PO Daily
- CrCl < 15 = DO NOT USE
When should Injectable or Oral anti-coag drugs be used?
- Injectable: VTE [Treatment/Prevention] and ACS
- Oral: VTE [Treatment/Prevention] and Stroke Prevention [Those with AFib]
Out of the two active enantiomers, which is that more potent one?
- S-Warfarin is more potent than R-Warfarin
- S-Warfarin is 2C9
What is the Oral direct thormbin inhibitor that is used and what is the Dosing for it?
Nonvalvular AFIb and Treatment of DVT/PE
- Dabigatran (Pardaxa)
- Nonvalvular AFib: 150mg PO BID [CrCl 15-30 = 75mg PO BID & CrCl < 15 = AVOID]
- Treatment of DVT/PE: 150mg PO BID; start after 5-10 days of parenteral anticoagulation
What are some Key Counseling Points for Rivaroxaban?
- if AFib: QD with evening meal
- if VTE: QD or BID with food at the same time everyday
- Missed dose: if BID; take 2 doses at the same time
What is the dosing for Vitamin K used as an antidote for Warfarin?
- 1-10mg PO/IV
If given IV, the rate CANNOT exceed 1mg/min or phebitis happens
For warfarin reversal, what are some of the important things to note when it come down to oral, SubQ, IM, and IV Vitamin K?
- Oral: should give 2.5-5mg for those WITHOUT bleeding
- SubQ: AVOID because of slow onset and repsonse
- IM: AVOID because fo hematoma risk
- IV: for SERIOUS bleed [could cause anaphylaxis; needs slow infusion]
How long should a VTE be treated for and can that be extended? If so, how?
- VTE by surgery or reverible risk factor = treat for 3 Months; can extend IF the patient is at a low-moderate bleed risk
- Extending therapy should use reduced doses of apixban or rivaroxaban
What is the way that we score someone usign HAS-BLED?
- H: HTN = 1
- A: Abnormal Liver or Kidney function = 1-2
- S: Stroke Hx = 1
- B: Bleeding Hx = 1
- L: INR [if on warfarin] =1
- E: Elderly [> 65yo] = 1
- D: Drugs [Aspirin, NSAIDS…] = 1-2
In 3 Factor Prothrombin Complex Concentrate, what are some of the important things that are found in it?
- Contains factors II, IX, X
For patinets that have a Mechanical Heart Valve, what medication is recommended for them for their AFib?
These patients are at the highest risk for stroke
- Warfarin not DOACs or Direct Thrombin Inhibitors
- Majortity fo people that have AFib do not have Mechanical Heart Valves
What should you do if the patient has cancer and is needing anti-coagulation?>
- WITH cancer: DOACs over other oral anti-coag and LMWH
- WITHOUT cancer: Dabigatran and DOACs over Warfarin for first 3 months
What is INR and what does it mean when the valves are high or low?
- INR: how long it takes for the blood to clot
- HIGH INR = blood clots slower [thinner]
- LOW INR = blood clots easier [thicker]
What are some of the drug interactions for Dabigatran
- Avoid with Rifampin or any P-gp inhibitor [CrCl < 50]
- Reduce dose to 75mg PO BID IF CrCl 30-50 AND using Drondarone or ketoconazole
- Cobicistat can increase exposure