anticoagulants Flashcards
what are some common anticoagulants?
heparin and warfarin
what are some new anticoagulants?
danaparoid **
and lepirudin
what are anticoagulants used for?
to prevent or manage thrombophlebitis, DVT, and PE
what is the main adverse effect of anticoags?
bleeding
heparin combines with ___ to inactivate which clotting factors?
antithrombin III
clotting factors IX, X, XI, and XII
heparin inactivates and inhibits what?
Inhibits conversion of prothrombin to thrombin
Inactivates thrombin, preventing conversion of fibrinogen to fibrin
Inhibits factor XIII, V and VIII and platelet aggregation
what drug is as effective as heparin?
LMWH
what does LMWH do?
prevention or management of thromboembolic disorder associated with surgery or iscehmimc complications of unstable angina and MI
do LMWH require close monitoring of blood coat tests?
no**
less thrombocytopenia than heparin
what is the most commonly used oral anticoagulants?
warfarin
what does warfarin do?
prevent synthesis of vic k-dep clotting factors I, VII, IX< and X
when do the effects of warfarin occur?
**3-5 days after oral use
indications of warfarin?
prevention or management of DVT, PE, and embolization associated with afib and prosthetic heart valves
used after MI
how soon should someone go off warfarin if they are going for surgery?
2-5 days bc thats the duration after discontinued
arterial thrombi are composed primarily of what?
plaelets
anti platelet drugs act by a variety of mechanisms to ___
inhibit platelet activation, adhesion, aggregation or procoagulant activity
MOA of aspirin ??
prevents formation of thromboxane A2 and thromboxane A2 aggregation. Activity persists for life of platelet (7-10 days)
MOA of NSAIDS?
inhibits cyclooxyrgenase reversibility. lasts until drugs are eliminated from circulation
MOA of ticlopidine? classification?
adenosine diphosphate receptor antagonist. it inhibits platelet aggregation by preventing ADP-induced binding between platelets and fibrinogen. last lifetime of paltelet
MOA of clopidogrel (placid)
similar effects as ticlopidine with fewer or less severe adverse effects
MOA of abiciximab? classification?
glycoprotein IIb/IIIa Receptor antagonists?
prevents binding of fibrinogen, von Willebranf factor and other molecules to GP IIb IIIa receptors on activated platelets
MOA of epitifibaride and tirofiban
prevent activation of GP IIb/IIIa receptors on the platelet surface and subsequent binding of fibrinogen and von Willebrand factor to platelets
classification of cilostazol?
phosphodiesterase inhibitor. inhibits that from metabolizing cAMP, thereby increasing cAMP which inhibits platelet aggregation and produces vasodilation
mgmt of intermittent claudication
what do thrombolytic agents do?
dissolve thrombi
stimulate conversion of plasminogen to plasmin
mom of acute, severe thromboembolic disease such as MI, PE, and iliofemoral thrombosis
goal is to reestablish blood flow and prevent or limit tissue damage
dissolve clots in arterial or venous catheters
examples of thrombolytic agents? ***
Alteplase* (clot buster for strokes), reteplase, and tenecteplase* are tissue plasminogen activators used in acute MI. Bind to fibrin and dissolve clot
different types of strokes? (%)
%85 ischeic
%15 hemorrhagic
drugs used to stop bleeding? if on warfarin? if on heparin? and LMWH?
Aminocaproic acid and tranexamic acid stop bleeding caused by overdoses of thrombolytic agents
Aprotinin inhibits plasmin and kallikrein, inhibiting fibrinolysis, inhibits breakdown of blood clotting factors
Protamine sulfate is antidote for heparin and LMWH
Vitamin K is antidote for warfarin overdose
** ^
vitamin C >500 mg/d may lower what lab value?
INR
> 400IU/d of vitamin e may inc effects of what drug
warfarin
what herbs may inc warfarin effects?
**alfalfa, celery, clove, feverfew, garlic, ginger, ginkgo, ginseng, and licorice
