International Normalized Ratio (INR)
- mathematical conversion of the PT ratio to account for differences in sensitivity of thromboplastin reagents
-relies upon reference thromboplastin with known sensitivity
a,c
Which patients are treated indefinitely?
a) any VTE + cancer
b) 1st VTE
c) 2nd VTE + unprovoked + low-moderate bleed risk
d) 2nd VTE + unprovoked + high bleed risk
b,d
Which patients are treated for 3 months?
a) any VTE + cancer
b) 1st VTE
c) 2nd VTE + unprovoked + low-moderate bleed risk
d) 2nd VTE + unprovoked + high bleed risk
f; 3 or more
One or two risk factors suggest high-risk of bleeding. T/F?
e
Which is ONLY used for life-threatening PE?
a) DOACs
b) Warfarin
c) UFH
d) LMWH
e) thrombolytics
DOACs, Warfarin, injectable
Rank our VTE treatments from best to worst.
CrCl < 30, critically ill
When do we use UFH? (2)
c
Which doesn't cross the placenta or get into breast milk?
a) DOACs
b) Warfarin
c) UFH
d) LMWH
e) thrombolytics
coagulation factors, liver enzymes, hyperkalemia
Monitoring for UFH? (3)
platelet factor 4
In HIT, what are the antibodies produced against?
50% decrease or absolute level < 100,000
What platelets levels can be indicative of a HIT reaction?
direct thrombin inhibitors; argatroban & bivalirudin
What do we use if a patient has HIT?
aPTT or anti-xa
What can we monitor to adjust the heparin dose?
HIT, hypersensitivity to pork, active bleeding
CIs of Enoxaparin? (3)
b
Which has a more predictable response i.e. no monitoring?
a) enoxaparin
b) dalteparin
c) fondaparinux
renal impaired, pregnant, low weight, kids
Which patients require Anti-Xa level monitoring w/ Enoxaparin? (4)
b
Which has no renal adjustments for CrCl < 30 ml/min?
a) enoxaparin
b) dalteparin
c) fondaparinux
b,c
Which is off-label for VTE and given with Warfarin?
a) enoxaparin
b) dalteparin
c) fondaparinux
c
Which can't use aPTT monitoring?
a) enoxaparin
b) dalteparin
c) fondaparinux
efficacy= anti-xa; safety = platelets, srcr, bleeding
Monitoring for Fondaparinux?
c
Which is easiest to dose, especially in obese patients?
a) enoxaparin
b) dalteparin
c) fondaparinux
2-4 days
How long do the effects of Fondaparinux last after discontinuation?
c
Which IS CONTRAINDICATED if CrCl < 30 ml/min?
a) enoxaparin
b) dalteparin
c) fondaparinux
a
Which HAS to be kept in its original bottle?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
e) betrixaban
a
Which HAS to be taken with a full glass of water?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
e) betrixaban
a
Which is NOT metabolized by CYP450?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
e) betrixaban
rivaroxaban; 15 & 20 mg
Which Factor Xa inhibitor has an issue with absorption?
What dose? * Not Dabigatran
e
Which is only approved for VTE prophylaxis?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
e) betrixaban
e
Which has the least hepatic metabolism, *excluding dabigatran?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
e) betrixaban
e
Which DO we take with food?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
e) betrixaban
2-3
What is the Therapeutic INR for most VTE patients?
ciprofloxacin, oxfloxacin, aspirin, bactrim, amiodarone, naproxen, ketorlac, ketoprofen, metronidazole, indomethacin
Which drugs interact with Warfarin? CABANA F (10)
< 2
What INR can we change Warfarin and start Dabigatran & Apixaban ?
< 2.5
What INR can we change Warfarin and start Edoxaban?
< 3
What INR can we change Warfarin and start Rivaroxaban?
LMWH, UFH, DOACs
Which medications do we give Cancer patients? (3)
LMWH
Which medications do we give Pregnant patients?
LMWH
Which medication do we avoid with Obese patients?
abrupt cessation; can increase clot risk
All factor Xa inhibitors have BBW for ?
b,c
Which has NO parenteral overlap?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
stop DOAC, start warfarin + parenteral at next DOAC dose; stop parenteral once INR is therapeutic
How do we switch from DOAC to Warfarin?
anti-factor xa
-designed to measure anti-thrombin-catalyzed inhibition of factor Xa
diluted thrombin time (dTT)
-based on thrombin time, but sample has been diluted & manipulated.
ecarin clotting time (ECT)
-originally developed for hirudin & DTIs
-involves use of ecarin from pit vipers
bleeding, mechanical heart valves, CrCl < 50ml/min, p-gp
CI's of Dabigatran? (4)
efficacy= ECT, dTT, aPTT; safety = CBC, LFTs, SrCr
Dabigatran Monitoring?
d
Which CANNOT be used if the patient has Afib?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban
d
Which CANNOT be used if the patient has a CrCl > 95?
a) dabigatran
b) rivaroxaban
c) apixaban
d) edoxaban