Term
| Mechanisms involved in homeostasis? |
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Definition
1. vessel wall 2. PLTs 3. coagulation system 4. Fibrinolytic system |
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Term
| 3 Parts of Coagulation Sysytem |
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Definition
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Term
Lab Test Commonly used to monitor for coagulation disorders and anticoagulation agents? |
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Definition
PLT function study PT (Prothrombin time)- Vit K, and factor VII aPTT- Heparin TT (Thrombin Time)- systemic fibrolytic system PLT count-
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Term
Indications for heparin use vs. LMWH use? |
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Definition
Heparin LMWH need for rapid anticoag. 1. prevent DVT PE Prevent venous thromboembolism Early TX of acute MI, UA CBG, vascular surgery, PTCA DIC
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Term
Mechanism of action of Heparin? |
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Definition
and factor Xabinds to AT, and changes At from a slow thrombin inhibitor to a very rapis inhibitor of thrombin heparin/At inactivate: thrombin factor (IIa), factors Xa, IXa, XIa,, and XIIa by inactivationg thrombin, fibrin formation is prevented and inhibits thrombin-induced activation of factor V and VIII
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Term
Major precautions of Heparin? |
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Definition
risk for bleeding cannot lyse present thrombi, only prevents new thrombi use with caution in pts >60 use with caution in pts with white clot syndrome
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Term
Adverse reactions of Heparin? |
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Definition
Bleeding fever, chills, HA Hyperkalemia (d/t suppression of aldosterone) Osteoporosis Elevated Liver enzymes anaphalytic reactions HIT
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Term
Lab tests used to monitor Heparin and LMWH? |
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Definition
Heparin- aPTT- 1.5-2xnorm ACT - PLT count, Hbg, HCT, and signs of bleeding should also be monitored LMWH- anti-factor Xa |
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Term
How are effects of Heparin reversed? |
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Definition
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Term
Precautions/adverse effects of Protamine? |
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Definition
Precautions -rapid IV injection may relaese histamine, leading to flushing, tachycardia, and hypotension -can cause pulmonary vasoconstriction leading to pulm HTN,and bronchoconstriction(pretreat with ASA,NSAID) -Allergic reaction |
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Term
Potential advantages of LMWH over Heparin? |
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Definition
convenience monitoring not required longer half life, less frequent dosing less incidence of HIT prevents DVT
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Term
Agents classified as LMWH? |
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Definition
Dalteparin Enoxaparin Tinzaparin
(TED) |
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Term
Signs and symptoms of HIT? |
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Definition
severe thrombocytopenia (<50,000) usually aroun day 6 of treatment development of heparin induced anti-plt assoc antibodies IgG mediated
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Term
How should HIT be treated? |
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Definition
Lepirudin, Argatroban until PLTs recover (>100,000) Do Not use warfarin (rx of gangrene) once PLT count recovers, start warfarin Do not ADX PLT transfusions
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Term
Direct Thrombin Inhibitors? |
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Definition
- Lepirudin
- Argatroban
- Bivalirudin
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Term
How are direct Thrombin inhibitors monitored? |
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Definition
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Term
How are direct Thrombin Inhibitors eliminated? |
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Definition
Lepirudin, and bivalirudin - Renal Argatroban- Hepatic |
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Term
Indications for use of Direct Thrombin inhibitors? |
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Definition
alternative to Heparin in HIT + pts PTCA adjunct (Bivalrudin)
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Term
Mechanism of Action for Warfarin? |
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Definition
produces anticoagulant effects by interfering with the cyclic conversion of Vit K and thus prevents the production of Vit K dependant cofactors (II, VII, IX, and X) |
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Term
How is warfarin therapy monitored? |
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Definition
INR goal- 2.0-3.0 PT 1.5-2.0 x norm(10-13) HCT signs of bleeding |
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Term
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Definition
Onset: 36-72hrs metabolized in liver highly protein bound
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Term
Major precautions of Warfarin therapy? |
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Definition
stop warfarin 3 days prior to surgery/invasive procedure increased risk of bleeding w/ ASA, NSAID, PCN many drug interactions (inducers/inhibitors)
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Term
Reversing effects of Warfarin? |
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Definition
For INR Greater than therapeutic but <5, without any significant bleeding; |
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Term
Management on high INR w/ Warfarin therapy? |
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Definition
INR >5.0 but <9.0 with no significant bleeding. Omit 1-2 doses, monitor the INR more frequently, and resume at a lower dose. Alternativly give 1.0- 2.5mg vitamin K po, particularly if there is a risk of bleeding. If a more rapid reduction in INR is required (surgery) then give 2-4mg of vitamin K with expectation that INR will fall within 24 hours. IF INR is still elevated in 24 hours then give anadditional 2mg po
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Term
Management of INR >9 w/o bleeding? |
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Definition
Hold warfarin give 3-5mg of vitamin K po, with expectation that INR will be significantly lower within 24-48 hours. Monitor INR more frequenlty and give additional vitamin K if necessary resume therapy at a lower dose. INR >20 with serious bleeding Hold wafarin, give vitamin K 10ng slow IV infusion, supplement with FFP, or prothrombin complex concentrate. Vitamin K can be repeated every 12 hours.
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Term
Management of Life threatening bleeding with warfarin therapy? |
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Definition
Hold warfarin, give prothrombin complex concentrate, supplement vitamin K 10mg by slow IV infusion. Repeat treatment as necessary.
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Term
Reversal of Warfarin therapy prior to surgery for pts with low risk of thromboembolism? |
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Definition
eg, patients without venous thromboembolism for >3 months or a patient who have experienced atrial fibrillation without history of stroke). Stop warfarin approximately 4 days prior to procedure, allow the INR to return to normal level, briefly administer postoperative prophylaxis (if the intervention creates a risk for thromboembolsim), give low dose heparin 5000 u SC, and simulateously begin warfarin therapy.
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Term
Reversal of warfarin therapy for pts with intermediate risk of thromboembolism? |
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Definition
Stop warfarin approximately 4 days prior to procedureand allow the INR to fall to normal. Cover the patient with low dose heparin 5000 u SC, beginning 2 days prior to surgery, or with a prophylactic dose of a LMWH, and then commence low dose heparin (or LMWH) and warfarin after surgery.
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Term
Reversal of warfarin therapy for pts with a high risk for throbembolism? |
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Definition
Patients with recent history <3 months of thrombembolic event, patients with a mechanical heart valve in the mitral position, or old model heart valve (Ball/cage). Stop warfarin approximaly 4 days prior to surgey. Allow the INR to return to normal. Cover the patient with full dose heparin or treatment dose of LMWH as the INR falls (approximately 2 days before surgery). Heparin can be given SC to outpatients then as continuous IV infusion once the patient is admitted. Stop the heparin 5 hours prior to surgery, or stop SC heparin or LMWH 12-24 hours prior to surgery.
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Term
Reversal of warfarin therapy for pts with low risk of bleeding? |
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Definition
Continue warfarin at lower dose and operate with INR of 1.3 to 1.5, anintensity shown to be safe in randomized trials of gynecological and orthopedic surgical patients. The dose of warfarin can be lowered 4-5 days before surgey Warfarin can be restarted after surgery and supplemented with low dose heaprin 5000 u SC if necessary.
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Term
Agents classified as antiplatelet agents? |
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Definition
ASA Clopidrogel Ticlopidine
(CAT) |
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Term
Mechanism of Action for antiplatelet agents? |
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Definition
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Term
Side effects of Ticlopidine? |
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Definition
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Term
How long should antiplatelet agents be held prior to surgery? |
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Definition
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Term
Agents classified as Glycoprotein IIb/IIIa inhibitors? |
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Definition
Abcixamab Eptifibatide Tirofiban
(TEA) |
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Term
Indications for use of Gltcoprotein IIb/IIIa inhibitors? |
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Definition
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Term
Contraindications of Glycoprotein IIb/IIIa inhibitors? |
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Definition
Contraindications Active internal hemorrhage or recent (within 6 weeks), clinically significant GI or genitourinary bleeding. History of CVA within 2 years, or CVA with significant neurological defecit Bleeding diathesis or administration of oral anticoagulants within 7 days unless PT <=1.2 times control Platalet count <100,000 Recent trauma or surgery ( within 6 weeks)
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Term
More contraindication for glycoprotein IIb/IIIa inhibitors? |
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Definition
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Term
How are Glycoprotein IIb/IIIa inhibitors reversed? |
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Definition
Reports indicate that thrombocytopenia respond well to stopping the drug, and is reversible, with recovery occurring over several days. The administration of platelets is recommended if severe thrombocytopenia develops or bleeding develop.
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Term
What agents are indirect acting thrombolytics? |
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Definition
Streptokinase Anistreplase
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Term
Major precautions associated with indirect acting agents? |
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Definition
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Term
Direct acting thrombolytics? |
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Definition
Alteplase Reteplase Tenecteplase Lanoteplase
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Term
Mechanism of action of thrombolytics? |
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Definition
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Term
Indications for use of thrombolytics? |
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Definition
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Term
Contraindications for use of thrombolytics? |
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Definition
Absolute Aortic dissection, acute pericarditis, active bleeding, previous cerebral hemorrhage, intracraneal vascular disease (aneurysm, AV malformation), cerebral neoplasm.
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Term
Relative contraindications for use of thrombolytics? |
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Definition
Potential hemorrhagic focus, nonhemmorhagic stroke or GI or GU hemorrhage in the past 6 mo. Major surgery, organ biopsy, puncture of non-compressible vessel, prolonged CPR w/ resultant chest trauma or in a patient that remains unconscious. Major trauma, or minor head trauma within past 2-4 weeks Severe hypertension (SBP >200 and/or DBP >120) at time of presentation. Diabetic retinopathy and menstruation are not contraindications . History of bleeding diathesis, hepatic dysfunction, cancer or pregnancy.
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