Term
Intrinsic coagulation pathway: initiated by? Slower or faster pathway? clotting factors involved? Test for the pathway? Drug that inhibits clotting? |
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Definition
Contact (endothelial damage/inside cut); slower/longer path; XII -> XI -> IX -> VIII -> X/II (common pathway); aPTT (activated partial thromboplastin time) test; heparin (fast acting) |
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Term
Extrinsic coagulation pathway: initiated by? Slower or faster pathway? clotting factors involved? Test for the pathway? Drug that inhibits clotting? |
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Definition
Trauma (outside the cut in plasma/vitamin K-liver dependent); faster/shorter path; tissue factor (III) -> VII -> X/II (common pathway); INR (International Normalized Ratio) test; warfarin (slow acting: preformed factors) |
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Term
warfarin mode of action; derivative of? |
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Definition
inhibits vitamin K epoxide reductase, which recycles oxidized vitamin K that has assisted carboxylation of pro-coagulation factors II, VII, IX and X AND anti-coagulation factors C and S; coumarin derivative |
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Term
warfarin sensitive factors? |
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Definition
pro-coagulation: II, VII, IX, X; anti-coagulation: Protein C and S |
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Term
warfarin mode of action, use, deliverery, test; pharmocogenomics? |
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Definition
inhibits production of clotting factors 2, 7, 9, 10 and anti-clotting proteins C and S; used for anti-coagulation (esp. extrinsic pathway); oral; INR (0.8 to 1.2 normal); VKORC1 (vitamin K epoxide reductase complex subunit 1 polymorphisms: African Americans more resistant/Asian Americans more sensitive (more bleeding), also different 2C9 phenotypes: fast (more clotting) and slow (more bleeding) metabolizers. |
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Term
Warfarin CPY450 metabolizer? inducers? inhibitors? |
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Definition
C29; inducers: Phenobarbitol, rifampin; inhibitor: amiodarone, fluoxetine, fluvastatin, zafirlukast |
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Term
Effects on warfarin of fibrates (why?), of high vitamin K foods, of antibiotics? |
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Definition
fibrates increase INR (higher INR = less clotting) because fibrates bind plasma proteins, freeing warfarin; foods decrease INR replacing unrecycled vitamin K; antibiotics increase INR, kills vitamin K producing bacteria, further decreasing available vitamin K. |
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Term
Warfarin antagonist (antidote)? |
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Definition
Vitamin K (delayed effect), FFP (fresh frozen plasma) |
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Term
Warfarin side effects? Why not aspirin for DVT? |
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Definition
necrosis from clots (if anti-clot proteins C & S are more sensitive to warfarin than clotting factors. Give heparin), osteoporosis, purple toe syndrome, FDA category X (not for use during pregnancy); aspirin inhibits platelet aggregation in arteries but veins are platelet poor. |
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Term
Heparain mode of action, use, delivery, test; found where endogenously? endogenous antagonist? |
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Definition
pentasacharide portion increases ATIII (antithrombin III) activation which inhibits factor X, 18 unit oligosacharide inhibits factor II (thrombin); used for anti-coagulation (esp intrinsic pathway); subcutaneous or IV; aPTT for high molecular weight version only;acid substance complexed with histamine in basophils; platelet factor IV (PF IV) - can't antagonize exogenous heparin |
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Term
Low molecular weight (LMW) heparin mode of action, test, advantages vs. high molecular weight (HMW) heparin? Disadvantages? |
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Definition
clean ATIII activators (factor X inhibitors); no aPTT (only can monitor factor X activity); adv: longer t1/2, more predictable response (factor X inhibition without factor II inhibition), outpatient; disadv: expensive, no reliable antagonist |
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Term
Heparain onset? with pregnancy? antagonist? side effects? |
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Definition
immediate onset (unlike warfarin); OK with pregnancy; protamine; Heparin-induced thrombocytopenia, osteoporosis (like warfarin) |
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Term
Protamine mode of action? side effect? use by itself? |
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Definition
heparain antagonist (pro-coagulant); vasodilation and lowered blood pressure; by itself is an anti-coagulant |
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Term
Hirudin mode of action, use, origin? |
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Definition
direct thrombin (factor II) inhibitor that stops fibrin formation from fibrinogen; anti-coagulation; leech buccal glands |
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Term
-rudin mode of action, use, advantage over heparin, examples |
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Definition
direct thrombin inhibitors (IV delivery); anti-coagulation; no ATIII activator and so no HIT (heparin-induced thrombocytopenia: occurs when antibodies to PF4/heparin complex form, activating platelets and leading thrombosis and lowered platelet count) |
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Term
lepirudin, desirudinm, and bivalirudin mode of action, use |
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Definition
direct thrombin inhibitors, anti-coagulation with out HIT |
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Term
argatroban mode of action, use, advantage over other similar drugs? |
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Definition
direct thrombin inhibitor, anti-coagulation, reversible |
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Term
-gatran mode of action, use, examples |
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Definition
direct thrombin inhibitor (oral delivery); anti-coagulation; ximelagatran (off market) and dabigatran |
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Term
-xabans mode of action, use, examples? |
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Definition
direct factor X inhibitors (oral delivery); anti-coagulation; apixaban and rivaroxaban |
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Term
Activation of which platelet receptors promote platelet aggregation? All of these activated receptors activate what receptor? |
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Definition
Thrombin, 5-HT (serotonin), epinephrine, ADP, PAF (Platelet activating factor), TXA2 (thromboxane A2); activate IIb/IIIa receptors that bind fibrinogin (factor I), which other platelets bind to as well causing aggregation. |
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Term
Activation of which platelet receptors inhibit platelet aggregation? All of these activated receptors deactivate what receptor? |
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Definition
cAMP/cGMP, adenosine (opposite of ADP), PGI2 (prostacyclin, opposite of TXA2), NO/EDRF (endothelial-derived relaxing factor, two terms often used interchangeably); deactivate IIb/IIIa receptors |
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Term
Asprin mode of action (with regard to platelets), use, dosage? |
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Definition
irreversible COX I inhibitor (thru acetylation) that stops production of PG, PCyclin & TX from arachidonic acid; because platelets mostly produce TX from COX-1 (which increases platelet aggregation), inhibition = anti-coagulation; works in LOW doses more selectively on platelet COX-1 than endothelial COX-1; |
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Term
thienopyridine mode of action, use |
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Definition
P2Y12/ADP receptor blocker; decreases platelet aggregation |
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Term
ticlopidine mode of action, use, indication? |
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Definition
P2Y12/ADP receptor blocker; decreases platelet aggregation; use when ASA is contra-indicated |
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Term
Clopidogrel, mode of action, use, indication, brand name, similar drug? |
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Definition
prodrug P2Y12/ADP receptor blocker (only 15% become active metabolites, rest degraded by esterases); decreases platelet aggregation; use when ASA is contra-indicated; Plavix; prasugrel |
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Term
Dipyridamole mode of action, use? |
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Definition
Platelet PDE-Inhibitor that stops adenosine reuptake, increasing adenosine; decreases platelet aggregation...There are also direct IIb/IIIa receptor inhibitors |
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Term
Anti-coagulants that can be used after thrombus is formed? coadminster with? |
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Definition
plasminogen activators (which break down fibrin/factor I); co-administer with a platelet aggregation inhibitor (because fibrin metabolites activate thrombin/factor II) |
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Term
streptokinase mode of action, use, advantage, disadvantage |
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Definition
plasminogen activator (also degrades factors V and VII (extrinsic path); thrombus breakdown; adv: cheap; disadv: binds with complexed and uncomplexed, plasma fibrin |
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Term
alteplase mode of action, use, advantage, disadvantage |
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Definition
plasminogen activator; thromus breakdown; adv: activates only plasminogen bound to fibrin (clot specificity) so fewer side effects; disadv: expensive |
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Term
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Definition
antidote for overdose of a plasminogen activator |
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