Term
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Definition
| refers to formation of platelet plug in a vessel hole |
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Term
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Definition
| refers to the coagulation cascade and formation of a fibrin plug generated from soluble fibrinogen by enzymatic cleavage |
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Term
| clinical difference btwn defect in fibrin plug and platelet plug |
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Definition
| fibrin plug: deep muscle or joint bleeds. platelet plug: mucosal bleeding, ecchymosis, petechiae |
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Term
| lab difference btwn fibrin and platelet plug defects |
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Definition
| fibrin: PT/PTT elevated, quantitive fibrinogen. Platelet: platelet count, bleeding time, platelet fn assays |
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Term
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Definition
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Definition
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Term
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Definition
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Definition
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Term
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Definition
| cofactor for the generation of the prothrombinase complex |
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Term
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Definition
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Term
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Definition
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Term
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Definition
| deficiency doesn't cause bleeding except under stress (surgery, trauma). Thrombin enhances 11->11a, which enhances thrombin in turn |
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Term
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Definition
| stabilizes fibrin clot; not reflected in PT or aPTT but by 5M urea clot lysis test. Cross links glutamine and lysine btwn soluble fibrins to make insoluble |
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Term
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Definition
| thrombin time: add thrombin to pt's plasma, tests fibrinogen adequacy and inhibitors of thrombin (e.g. heparin) or inhibitors of fibrin polymerization |
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Term
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Definition
| prothrombin time: add active tissue factor (factor III). used primarily to monitor anticoagulation therapy. NORMAL in hemophiliacs! |
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Term
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Definition
| activated partial thromboplastin time: tests rxn to negatively charged surface (glass) beginning w/ factor 12. Calcium independent. MAY NOT DETECT some bleeding disorders |
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Term
| site of synthesis of coagulation factors |
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Definition
| ALL are made in the liver. Platelets make 5, VWF, and PAI-1. Endothelium makes vWF, 7, tPA, uPA. |
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Term
| 4 steps of platelet plug formation |
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Definition
| adhesion, aggregation, granule release/amplification, support of coag. cascade. |
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Term
| mechanisms of thrombocytopenia |
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Definition
| decreased or ineffective pdxn, destruction, redistribution, dilution |
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Term
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Definition
| vWF deficiency or defect, affects 1% of caucasians. Autosomally inherited. |
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Term
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Definition
| von Willebrand factor; binds platelets to damaged endothelium. carries F8, complete def. is indistinguishible from hemophilia A |
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Term
| 2 screening tests for primary hemostasis |
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Definition
| PFA100 and bleeding time (less reliable, poor screening test) |
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Term
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Definition
| blood is run thru column coated w/ collagen and checks how much time it takes to close aperture. better than bleeding time for checking primary hemostasis. |
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Term
| ristocetin cofactor assay |
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Definition
| tests ability of vWF to bind platelet GPIb (functional test of vWF, esp. HMW multimers) |
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Term
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Definition
| tests platelet response to specific agonists |
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Term
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Definition
| widely variable, interobserver reliability is poor, poor predictor of operative outcome |
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Term
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Definition
| plasma is separated from blood and put into a citrate tube (binds Ca, prevents clotting). Phospholipid is added (partial thromboplastin), and contact activator is added. Ca is added back in and clotting time is measured. |
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Term
| minimal hemostatic level of F 8,9,11 |
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Definition
| 30% and up should all clot normally |
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Term
| prolonged aPTT indicates: |
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Definition
| deficiency in F12,11,9, 8,10,5, 2 and fibrinogen. most sensitive for 12,11,9,8, less for 2 and fibrinogen |
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Term
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Definition
| factor 12- deficiency may cause prolonged aPTT but no disease |
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Term
| causes of spurious prolongation of aPTT |
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Definition
| elevated plasma citrate, heparin in tube, or clotted sample that pulls out clotting factors |
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Term
| Inhibitors of clotting in vitro; promotes clotting in vivo |
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Definition
| lupus anticoagulant and anticardiolipin antibodies |
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Term
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Definition
| 50-50 mixing study will differentiate btwn factor deficiency and inhibitor |
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Term
| specific tests for secondary hemostasis |
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Definition
| pt's plasma added to factor deficient plasma- clotting time plotted against mix of normal plasma and factor deficient plasma. Must be done once for each factor to be tested. |
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Term
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Definition
| rate of conversion of fibrinogen to fibrin, which depends on amount of fibrinogen and quality of fibrinogen |
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Term
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Definition
| can confirm that inability to clot is due to heparin |
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Term
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Definition
| inhibits polymerization, causes problems in 1' and 2' hemostasis, causes prolonged thrombin time |
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Term
| causes of prolonged thrombin time |
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Definition
| congenital afibrinogenemia, dysfibrinogenemia, heparin, xs fibrinogen degredation products (as in DIC), paraproteinemia, renal failure, amyloidosis |
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Term
| Dilute whole blood clot lysis time |
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Definition
| screens for accelerated fibrinolysis; measures time to clot breakdown in a sample of plasma (euglobulin lysis time) or whole blood (DWBCLT). Shortened in advanced cirrhosis, also venous thrombosis and renal dz |
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Term
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Definition
| receptor for 7a and also vital for angiogenesis, constitutively expressed on subendothelium and bone marrow derived microparticles. induced by cytokines, LPS, and VEGF |
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Term
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Definition
| Tissue Factor Pathway Inhibitor complexes F10a and F7a to shut down clotting via their pathway. This forces the TF;F7a complex to activate factor 9 instead |
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Term
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Definition
| converts glutamic acid into gamma carboxy glutamic acid |
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Term
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Definition
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Term
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Definition
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Term
| thrombin amplifies its own production how? (2 ways) |
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Definition
| activates factor 11, activates platelets leading to increased surface for coag cascade |
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Term
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Definition
| important anticoagulant; major scavenger of xs thrombin. knockout -> death! deficiency-> clots! activated by GAGs on endothelial surface. can neutralize F10a and F9a |
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Term
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Definition
| cofactor for APC; allows APC to clip factors 8a and 5a |
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Term
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Definition
| APC comes from PC that has been converted by the thrombin-TM complex on ET. Inhibits F5 and F8, and PAI-1 (to increase fibrinolysis). Inhibited by APCI |
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Term
| Dense granules (platelet) |
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Definition
| contain ADP, ATP, serotonin, and Ca (platelet agonists!) |
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Term
| alpha granules (platelet) |
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Definition
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Term
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Definition
| thrombopoietin, mpl ligand on plateletes and megakaryocytes, secreted constitutively by liver. cellular levels vary w/ platelet and MK size |
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Term
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Definition
| an error in diagnosis of thrombocytopenia, look at the edge of a PBS to see the platelets in these cases |
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Term
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Definition
| antibodies to platelets reduce their amount, but more young platelets are made, allowing sufficient clotting for most pts |
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Term
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Definition
| Idiopathic (immune) Thrombocytopenic Purpura is caused by antibodies against common platelet antigens (i.e. platelet transfusions are of little use). May be caused by drugs, infection, or autoimmune dz. Splenic MPs phagocytose platelets. Often cured by splenectomy. |
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Term
| 3 As of platelet function |
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Definition
| Adhesion to disrupted endothelium, Activation (become sticky), Aggregation (recruit other platelets to clot) |
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Term
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Definition
| ptn on the surface of platelets that reversibly binds vWF on damaged endothelium. Induced by fast flow in bloodstream |
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Term
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Definition
| ptn on surface of platelets that stably binds endothelium |
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Term
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Definition
| storage for vWF multimers in endothelium |
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Term
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Definition
| cuts HMW vWF into smaller, less sticky pieces for constitutive circulation. deficiency--> thrombotic thrombocytopenic purpura (TTP) with lots of clotting |
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Term
| platelet agonists in vivo |
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Definition
| collagen w/ GP6, cWF w/ GP9B, thrombin, ADP, and epinephrine |
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Term
| Platelet suppressors in vivo |
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Definition
| endothelial NO, endothelial prostacyclin, and CD39 (breaks down ADP) |
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Term
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Definition
| expressed on platelets, upregulated in activation, binds fibrinogen or vWF, vital for platelet aggregation |
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Term
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Definition
| vWF Ag quantification detects circulating levels from lo and hi MW multimers. Ristocetin cofactor assay gives functional assessment of vWF action. vWF multimer assay looks at proportions of each multimer. F8 level. Ristocetin induced platelet aggregation (RIPA) uses pt's plasma and platelets checks sensitivity of platelet vWF binding |
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Term
| ristocetin induced platelet aggregation (RIPA) |
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Definition
| uses pt's platelets and plasma and assesses sensitivity of platelet vWF binding |
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Term
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Definition
| 1: too little vWF. 2:dysfunctional vWF (several subtypes). 3: complete lack of vWF |
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Term
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Definition
| gel electrophoresis separates multimers of vWF, checks for appropriate proportions of HMW vWF |
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Term
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Definition
| X linked disorder of Factor 8 |
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Term
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Definition
| synthetic desmopressin stimulates endothelial release of vWF is great for treating vW dz in anticipation of bleeding (period, dentist) but can only be used a couple days at a time (tachyphylaxis) |
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Term
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Definition
| DDAVP, Cryoprecipitate, purified vWF:8, anti fibrinolytics, and estrogen |
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Term
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Definition
| autosomal recessive, platelet GP 1B9 deficiency. PBS: mild to moderate thrombocytopenia, large platelets. Low RIPA, nl RCo . Corresponds with vWD |
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Term
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Definition
| lifelong mucocutaneous bleeding, autosomal recessive def of alpha granules |
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Term
| Glanzmann's thrombasthenia |
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Definition
| autosomal recessive defect in platelet GP IIb/IIIa. Normal platelet count, severe mucocutaneous bleeding, Fe deficiency, prolonged bleeding time, absent aggregation to any agonist except ristocetin. |
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Term
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Definition
| irreversibly inhibits COX1 , prevents formation of TXA2. |
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Term
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Definition
| Thrombomodulin, Ptn S, and F5a |
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Term
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Definition
| MCV is over 100 fL, indicates dfx in DNA pdxn and cell division, could be B12 or folate def. Retics will be lo, bili hi, cells all over body have trouble dividing. |
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Term
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Definition
| GAG that activates antithrombin to prevent thrombin from promoting clotting |
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Term
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Definition
| induces ET to release tPA, ET derived relaxing factor and prostacyclin; induces monocytes to express uPA receptors; complexes with TM to activate ptn C; induces platelet mediated clot retraction |
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Term
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Definition
| a very active serine protease from plasminogen; degrades fibrin, F5, F8, and deactivates platelets. a-2-PI inhibits it, uPA and tPA activate it. Active in angiogenesis. |
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Term
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Definition
| tissue plasminogen activator; comes from ET, dissolves clots, converts plasminogen to plasmin. released in response to increased venous pressure |
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Term
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Definition
| Plasminogen Activator Inhibitor. Does whjat it says. |
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Term
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Definition
| binds ET and allows conversion of plasminogen to plasmin |
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Term
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Definition
| excessive fibrinolysis by plasmin that mimics hemophilia symptomatically w/ bleeding into joints |
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Term
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Definition
| cross linked fibrins from clot breakdown; its presence tells you 3 things: you have functional thrombin that made fibrin, F13 cross linked it, and plasmin was activated to break down the clot. |
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Term
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Definition
| Thrombin activated fibrinolysis inhibitor; cuts off lysine residues that plasminogen and tPA would bind to, making the clot more stable. |
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Term
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Definition
| disorder of hemostasis resulting from excess generation of thrombin (usually from triggering of intrinsic system by TF) |
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Term
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Definition
| Thrombocytopenia, ^D-Dimer, ^fibrin monomer, low-nl fibrinogen, positive protamine test |
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Term
| Kasabach Merritt syndrome |
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Definition
| localized DIC syndrome, livable |
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Term
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Definition
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Term
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Definition
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Term
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Definition
| epsilon amniocaproic acid, binds lysine residues, acts as an antifibrinolytic. blocks tPA and plasminogen |
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Term
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Definition
| Deficiency in AT, Ptn C, or Ptn S; APC resistance, PT gene mutation, homocysteinemia, or elevated F8, F11. |
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Term
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Definition
| (factor 5 leiden) arginine target of ptn S/APC cleavage is mutated, preventing breakdown of f5a and increasing risk of thrombus 5x |
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Term
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Definition
| hallmark of factor 13 deficiency; pts will bleed, clot, and then begin bleeding again later |
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Term
| factors unique to the intrinsic pathway |
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Definition
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Term
| factors in the common pathway |
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Definition
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Term
| factors unique to the extrinsic pathway |
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Definition
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Term
| factors requiring Ca and vitamin K |
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Definition
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Term
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Definition
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Term
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Definition
| refers to the complex of F9 and F8 together |
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Term
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Definition
| refers to complex of F10a and F5a |
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Term
| what test is used for coumadin/warfarin monitoring? |
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Definition
| PT tests levels of F7, which has the shortest halflife of the vitamin K dependent factors |
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Term
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Definition
| Plavix; blocks ADP receptor on platelets |
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Term
| platelet collagen receptor |
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Definition
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Term
| conformational change in platelet exposes |
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Definition
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Term
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Definition
| glycoprotein IIb/IIIa receptor irreversible inhibitor |
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Term
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Definition
| abciximab, eptifabitide, tirofiban |
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Term
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Definition
| clopidogrel and ticlopidine |
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Term
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Definition
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Term
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Definition
| small bleeds (petechiae, purpura, epistaxis, mucocutaneous bleeds) |
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Term
| Sx of secondary hemostasis disorder |
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Definition
| bleeding into joints, large ecchymoses |
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Term
| unfractionated heparin vs. LMW heparin |
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Definition
| unfractionated: effective, reversible, rapid, short t/2, unpredictable, inpatient, more HIT. LMW:effective, fixed dosing, more predictable, less HIT, subQ, not fully reversible, difficult for obese or renal pts |
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Term
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Definition
| pentasaccharide; selective inhibitor of F10a, can be used in pts with HIT |
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Term
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Definition
| blocks vitamin K epoxide reductase, oral, outpatient, dietary precautions, unpredictable. OD may cause warfarin necrosis w/ microvascular clots |
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Term
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Definition
| oral factor 10a inhibitor, broad therapeutic index |
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Term
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Definition
| argatroban, lepirudin, bivalrudin, dibagitran |
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Term
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Definition
| ticlopidine and clopidogren irreversibly inhibit ADP receptor on platelets; both prodrugs activated in hepatic metabolism |
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Term
| First line anti-platelet therapy |
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Definition
| aspirin blocks COX1 irreversibly and blocks platelet aggregation for up to 5 days |
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Term
| level of TPO in aplastic anemia |
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Definition
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Term
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Definition
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Term
| normal distribution of platelets |
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Definition
| 1/3 of platelets are in a normal spleen at any given time |
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Term
| daily platelet turnover rate |
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Definition
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Term
| normal platelet survival time |
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Definition
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Term
| Infections associated with autoimmune thrombocytopenia |
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Definition
| H. pylori, Hep C, and HIV |
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Term
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Definition
| gain of function mutation to the GP1b9, "mops up" vWF from the body |
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Term
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Definition
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Term
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Definition
| inhibits phospholipid dependent in vitro coagulation tests, esp. PTT. Causes arterial and venous thrombosis, fetal death. It is an antibody against clotting proteins that, when combined, develops affinity for phospholipid. |
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