anticoagulants Flashcards
(57 cards)
heparin MOA and what pathways it inhibits
inhibits intrinsic and final common pathways. heparin binds to antithrombin and accelerates its anticoagulation ability 1,000 fold. also inhibits platelet function.
failed heparinization should prompt consideration of which deficiency
antithrombin deficiency
charge, solubility, vd of heparin
large, negatively charged, water soluble, and have small vd
how is heparin metabolized
via heparinase
2 pathways for heparin elimination
degradation by macrophages and renal excretion
does heparin cross the placenta
no
1u of heparin is defined as
volume of heparin containing solution that prevents 1mL of citrated sheep blood from clotting for 1h following addition of .2mL of 1:100 CaCl
standard amount of heparin administered for heart surgery
300-400u/kg
heparin dose for VTE prophylaxis
5000u SQ BID or TID
active VTE dose
5000U IV then infusion of ~1250U/h to maintain aPTT 1.5-2.5x normal
unstable angina and acute MI dose of heparin
5000U then 1000U/h infusion
side effects of protamine
HoTN r/t histamine release (give slowly), pHTN r/t TXA2 and serotonin release, allergic rx (esp with hx of previous sensitization to NPH insulin, fish allergy, vasectomy, multiple drug allergies
MOA of warfarin
inhibits enzume vitamin k epoxide reductase complex/ VKORc1 which is responsible for converting vitamin K to its active form.
indirectly blocks 2,7,9,10, protein c and protein s
antidotes of warfarin
vitk and FFP
how long after start of warfarin will therapeutic concentration be achieved?
36-72h
for minor procedures, how is it recommended to reverse warfarin
10-20mg vitk
for increased risk procedures, how is it recommended to reverse warfarin
1-2u FFP, recombinant factor 7a or prothrombin complex concentrate
risk factors for vitamin k deficiency include
poor diet intake, antibiotic therapy (decreases healthy flora for vitk absorption), malabsorption due to biliary tract disease, hepatocellulr disease
another name for exogenously administered vitk
phytonadione
how many hours does it take to restore vitk dependent clotting factors in the blood after vitk administration
4-8h
dosage of vitk
10-20mg PO IM or IV
which route should be avoided for vitk administration
IV r/t life threatening anaphylaxis
ADP receptor inhibitors include (4)
prasugrel, ticlodipine, clopidogrel, ticagrelor
stop how long before procedure: clopidogrel
5-7d
