Hematology Flashcards
What are 4 antiseptic agents?
aspirin
Dipyridamole
Clopidogrel
Tirofiban
What are 5 anticoagulants?
Heparin Enoxaparin sodium Warfarin sodium Dabigatran etexilate Rivaroxaban
What causes glycoprotein IIb/IIIa to be exposed?
collagen allowing platelet aggregation and aggregation forming a clot
What is the final step in Hemostasis and results in a meshwork of fibrin that traps blood cells?
Clotting
What are the 3 major types of drugs to diminish thrombus formation?
Anticoagulants
platelet inhibitors
Thrombolytics
What interferes with fibrin formation and are used to prevent thrombus development and extension?
Anticoagulants
What is the site of formation of clotting factors?
Liver
What is the site of production of bile salts that facilitate the absorption of vitamin K and aid in the production of clotting factors II,VII, IX, and X?
Liver
What are two major anticoagulants?
Heparin
Warfarin
What is the main complication of anticoagulants?
Bleeding
What anticoagulant is a large, endogenous, sulfated glycosaminoglycan found in mast cells?
Heparin
What does Heparin bind to?
Antithrombin III
What does antithrombin III inhibit?
Thrombin factor 2 and Xa
How must Heparin be administered and why?
parenterally due to large molecular size
T/F: When heparin binds to plasma proteins it can not bind to antithrombin III
True
What anticoagulant is needed when a rapid effect is desired?
Heparin
What is the antidote to Heparin?
protamine sulfate (interferes with heparin’s ability to bind to antithrombin III)
What is Heparin derived from?
Animal sources
What is used to monitor Heparin’s efficacy?
Activated partial thromboplastin time (APTT)
What drug is Low Molecular Weight Heparin (LMWH)?
Enoxaparin
What is affected more with LMWH?
Factor Xa
What drugs directly bind to the active site of thrombin, inhibiting its effects on fibrinogen?
Direct Thrombin Inhibitor
What Direct Thrombin Inhibitor inhibits coagulation by preventing thrombin mediated effects binds and inactivates both free and fibrin bound thrombin?
Dabigatran Etexilate
What is an alternative to warfarin in patients with Afib?
Dabigatran
What Inhibits the active site of factor Xa?
Rivaroxaban (Xarelto)
What Vitamin K Antagonist inhibits the synthesis of vitamin K dependent clotting factors II, VII, IX, and X and anticoagulant proteins C and S?
Warfarin
How long is the therapeutic effect delayed for with Warfarin?
4-5 days
What food increases warfarin’s anticoagulant actions?
Garlic, Ginger, and Ginkgo biloba
What is the gold standard for monitoring warfarin?
INR
What is a sufficient INR?
2-3
How do anti-platelet drugs inhibit platelet aggregation?
Inhibition of Thromboxane (TXA2) synthesis
Inhibition of phosphodiasterase and activation of adenylate cyclase
Inhibition of adenosine (ADP) binding
Antagonism of platelet glycoprotein IIb/IIIa receptor
What does Aspirin irreversibly acetylate?
cyclooxygenase 1 (Cox1)
What does an increase in adenylate cyclase leads to?
Inhibition of phosphodiasterase?
Increase adenylate cyclase: rise in cAMP that blocks TXA2 production
Inhibit phosphodiesterase: same thing
What drug inhibits phosphodiesterase?
Dipyridamole
What drug inhibits platelet aggregation and binds to the platelet P2RY12 receptor?
Clopidogrel
What drug is a reversible antagonist of fibrinogen?
Tirofiban
What Salicylate’s main effect is blockade of thromboxane A2 production from arachidonic acid in platelets, by irreversibly acetylating the enzyme cyclooxygenase, the rate limiting step in thromboxane synthesis?
Aspirin
Aspirin inhibits production of prostacyclin from what?
endothelial cells
What adverse drug reaction does aspirin cause?
Abdominal discomfort
What drug is a phosphodiesterase inhibitor, and is used for post-op thromboembolic complications and to prevent cerebrovascular ischemia?
Dipyridamole
What drug is a Adenosine Diphosphate inhibitor that irreversibly blocks the ADP receptor on platelets, thus reducing platelet aggregation?
Clopidogrel
What drug is the main alternatives to Aspirin for preventing thrombotic events in atherogenic patients with recent myocardial infarctions, strokes, transient ischemic attacks, and unstable angina?
Clopidogrel
What must Clopidogrel be activated by?
CYP450
What drugs prevent fibrinogen from interacting with the platelet glycoprotein IIb/IIIa receptor thereby inhibiting platelet aggregation?
Glycoprotein IIb/IIIa Inhibitors
Give an example of a Glycoprotein IIb/IIIa Inhibitor?
Tirofiban
What kind of drugs are a major defense mechanism to localize clot formation and may restore vessel patency and flow?
Fibrinolytics
What are the most important fibrinolytics?
tissue type plasminogen activator (t-PA) and pro-urokinase
What dissolves existing thrombi through activation of plasminogen activators and is used when rapid dissolution of a clot is required to preserve organ and limb function or valve function of veins?
Thrombolytics
