Antithrombotics extras (do last) Flashcards
What is the BBW for antithrombotics?
spinal anesthesia/puncture –> hematoma –> paralysis
The treatment for HIT is__________.
Fondaparinux or argatabon.
Do NOT give warfarin.
Pentasaccharide increases _________ affinity for _________ (direct pathway).
Antithrombin
Factor Xa
Activation of ____________ will form a fibrinogen bridge for platelet aggregation.
GP IIb/IIIa
What inhibits Factor IIa (thrombin)?
Dabigatran
Fondaparinus
Warfarin
What are indications for use of thrombolytics?
ischemic stroke <4 h
MI untreatable by PCI <14 h
Idarucizumab (Praxbind) is the antidote for ___________.
Dabigatran
Why is it important to start heparin along with warfarin?
Warfarin has a slow onset of action because existing functional clotting factors have to turn over. If you do not give heparin, there may be an initial procoagulant effect due to inhibition of Protein S and C.
Alteplase mechanism of action
binds fibrin to activate plasminogen on a fresh clot
What drugs REVERSIBLY blocks GP IIb/IIIa from binding to fibrinogen and vWF
Abciximab
Tirofiban
Eptifibatide
What are the DIRECT Factor Xa inhibitors?
Ribaroxaban
Apixaban
What inhibits Factor Xa?
Warfarin
Rivaroxaban
Enoxaparen
Streptokinase mechanism of action
activates circulating plasminogen
The benefit of using Ribiroxaban or Dabigatran
there is a predictable response, do not need routine monitoring (in comparison to warfarin!)
What are the DIRECT factor IIa (thrombin) inhibitors?
Dabigatran
Others used only in invasive cardiology
Drugs that inhibit Pgp/CYP34A will ________ efficacy of Rivaroxaban.
increase efficacy
Long polysaccharide chains bridge ___________ and __________.
Antithrombin
Factor IIa
What inhibits factor VIIa?
Warfarin
Why does heparin require IV or SQ administration?
it is very acidic so always negatively charged, highly sulfated, does not cross GI/placenta/brain barrier
Do not give Aspirin to people < age ______ because it may cause _____ syndrome in the setting of a viral infection/vaccine.
19
Reye
The goal/target of anticoagulation is to diminish activity of Factors _______ and/or _______.
Xa
IIa
Inhibition of COX-2 results in____
Decrease in pro inflammatory prostaglandins and an increase in anti-inflammatory lipoxins
Clopidogrel and Prasugrel irreversibly block ____________.
P2Y12, the ADP purine receptor on platelet
What is the antidote for heparin?
Protamine Sulfate
inactivates heparin by ionic binding to polysaccharide chains
Aspirin is metabolized in the liver to _________.
salicylic acid
Half life is inversely proportional to _________ of the heparins.
chain length
HIT develops when _______ binds to heparin and the body forms antibodies to the complex.
PF4, released from platelet granules
LMW Heparin (Enoxaparin) and Fondaprinux are eliminated by the ________.
kidney
What irreversibly blocks COX-1?
Aspirin
Warfarin is metabolized by __________ in the liver. People who are poor metabolizers are at increased risk of ____________.
CYP2C9
MI, stroke
What does gamma carboxyglutamate (Gla) do?
Chelates calcium to enable factors VII, IX, and Xa as well as Protein C and Protein S to the platelet membrane
What does antithrombin do?
neutralizes coagulation proteases
Drugs that induce Pg will __________ efficacy of Dabigtran.
Decrease
Inhibition of COX-1 decreases platelet recruitment/activation by what mechanism?
Decreases arachidonic acid conversion to thromboxane (TXA2), which is needed for fibrinogen bridging
________(antithrombin catalyst) can be used in pregnant women as long as there are no preservatives in it.
Heparin
Contraindications for Aspirin
NSAID hypersensitivity
asthma/rhinitis/nasal polyps
Aspirin is excreted by the _______.
Kidney
Overdose of Aspirin results in ______
uncoupling of oxidative phosphorylation
metabolic acidosis, seizures, coma
