anti-coagulants, anti-platelets, thrombolytics (functions)

how do thrombolytics work

promote conversion of plasminogen to plasmin, which lyses fibrin clots

when do we use thrombolytics

tx for acuute ST elevation MI when PCI is unavailable

what are indications for thrombolytics

non-hemorrhagic CVA, pulmonary embolism

what thrombolytic requires post-thrombolysis use of IV heparin

Alteplase

what thrombolytic is most fibrin specific

tenecteplase

T/F agents more fibrin specific are more effective and produce less bleeding

truewhat

what are contraindications to thrombalytics

hemorrhagic CVA, surgery within 2 weeks, bleeding disorders, aortic aneurysm/dissection, uncontrolled HTN

what do antiplatelets do

inhibit platelet aggregation

how does aspirin work

irreversibly inhibits COX, non-selective NSAID for both COX 1 and 2, and prevents formation of thromboxane 2, causing vasoconstriction (for 7 days)

what are indications for aspirin

CAD, MI, post-CABG/PCI, (Afib if other meds are contraindicated)

what are side effects of aspirin

GI-related, also causes confusion from acidosis

how do platelet aggregation (P2Y12) inhibitors work

inhibits binding of ADP to P2Y12 receptor, inhibiting platelet aggregation (for 7 days)

what are indications for platelet aggregation inhibitors

reduction of atherosclerotic events

what are examples of platelet aggregation inhibitors

clopidogrel, prasugrel, ticagrelor, ticlopidine

what are the components of Dual antiplatelet therapy

aspirin + platelet aggregation inhibitor

when do we use glycoprotein 2b/3a inhibitors

most potent antiplatelets, given intravenously during PCI, unstable pts with resistant angina

what are the anticoagulants

heparin, direct thrombin inhibitors, low molecular weight heparin warfarin, direct oral anticoagulants

how does heparin work

binds to antithrombin III, prevents platelet aggregation and thrombuus formation

what pathway does heparin work on

intrinsic

what level do we maintain PTT at during heparin use

2x base level

what are indications of heparin use

acute MI, post MI, untable angina, DVT, PE, AFib

can we use heparin in pregnancy

yes!

what are direct thrombin inhibitors used for

thrombocytopenia (HIT)

what are advantages to LMWH (enoxaparin)

doesnt require lab monitoring

what are disadvantages to LMWH

costly, can accumulate in pts with renal insufficiency

how does warfarin work

oral; interferes with vitamin K, thus reducing production of clotting factors

what is the therapeutic INR for warfarin

2.0-3.0 (2.5-3.5 if valves)

what are indications for warfarin use

DVT, PE, impaired EF, AFIb, replaced valveswh

what are contraindications for warfarin

pregnancy, bleeding disorders, pts with poor compliants and hx of falls

what intervention is needed if INR >10

vitamin K or fresh frozen plasma ASAP

what are the direct oral anticoagulants (DOACs)

pradaxa, xarelto, eliquis

what pathway do DOACs work on

common

what are the uses of DOACs

stroke prevention in non-valvular AFib, tx and secondary prevention in DVT/PE, initial tx and VTE prophylaxis in ortho surgery

what is pradaxa

direct thrombin IIa inhibitor, reversable

what is xarelto

factor Xa inhbitor, reversible, take with food

what is eliquis

factor Xa inhibitor, use lower dose for: age >80, weight<130, serum Cr>1.5