chapter 9- coagulation Flashcards
what is hemostasis
halt of blood
-natural process in response to injury to tissue
how does hemostasis occur
vasoconstriction, formation of a platelet plug, activation of clotting factor, reparation of the opening in a damaged vessel
what do plasminogen and fibrin do
form a clot
what does Plasmin do
dissolves a clot
what do capillaries do
connect veins and arteries
what organ affects clotting the most
the liver
define intrinsic and extrinsic
I: blood vessel damage
E: tissue damage
what is thrombogenisis
formation of and dissolving of clot
what is arterial thrombosis, an incomplete blockage, complete blockage and the cause.
obstruction of arterial blood flow
-caused by damaged arterial endothelium, causing platelet activation
In: deficient blood flow, causing ischemia
C: obstruction, causing necrosis
Causes: atherosclerosis, HTN, turbulent arterial blood flow
what is venous thrombosis and DVT and the cause
result of venous stasis, thrombin, and procoagulant substances become concentrated
-easily detached
DVT, PE if detached
-common in lower extremities, will block the right side of the heart
Assessment: pain redness, swollen, hot, some will be asymptomatic
caused by: decreased activity
what is atherosclerosis
elevated lipid levels, causing plaques to form
-progressive
-causes MI and TIA, CVA and strokes
what is TIA
transient ischemic effect, occurs before CVA and strokes
what are anticoagulants used for
thrombotic disorders, prevent venous thrombus
-thrombophlebitis, DVT and PE, A fib
what are antiplatelets used for
prevent arterial thrombosis
what are thrombolytics used for
dissolve thrombi and limit tissue damage
what is thrombophlebitis
vein inflammation
main adverse effect of anticoagulants
bleeding
challenge with anticoagulants
dosing for therapeutic levels is challenging
what do you have to do if administering IV heparin
draw labs every six hours until the therapeutic dose is achieved
-aPTT/PTT
-levels should be 60-80
the primary use for SQ heparin
DVT prevention for in-bed restricted Pts, 5000u is a common dose
what is the antidote for heparin
protamine sulfate
why is enoxaparin not used often
price
what are warfarin levels measured by
INR and PT
what is the antidote for warfarin, and what foods affect it
Vitamin K
-green leafy veggies, green tea, grapefruit juice, cranberry, alcohol
how does fondaparinux work and how is it given
xa inhibitor
Sub Q and IV
when is fondaparinux used and why only then
when heparin causes thrombocytopenia
PRICE
how does dabigatran work and how is it administered
direct thrombin inhibitor, treats complications of Afib and stroke prevention
PO twice daily
what is the antidote to dabigatran
idarucizumab
why is dabigatran not used often
compliance issues with taking twice daily
how does rivaroxaban work and how is it given
Xa inhibitor treats Afib complications and stroke and DVT prevention
PO once daily
how does apixaban work and how is it given
The most common Xa inhibitor, used to treat Afib complications and stroke prevention
PO twice daily
benefit of taking something other than warfarin
does not require regular testing, could lead to higher complications
-DO NOT STOP TAKING
side effects other than bleeding for anticoagulants and possible complications
GI upset
Should not take NSAIDS
lots of dietary and drug interactions
such as… allopurinol, -cillin antibiotics, and birth control
what is ecchymosis
increased bruising, bleeding episodes, dizziness, lightheadedness, hypotension, low hgb/hct, bloody urine, chest pain, SOB, hemoptysis
SIGNS DOSE IS TOO HIGH
ways antiplatelets work
-inhibit activation
-inhibit adhesion
-inhibit aggregation
-inhibit the procoagulant activity
how does clopidogrel work
inhibits ADP receptor on platelets
NO ANTIDOTE
Long first pass effect
side effects of clopidogrel
rash and diarrhea
what can clopidogrel be used with
aspirin
how does aspirin work, and when is it used
thromboxane A2 inhibitor
prevents platelet aggregation and thrombus formation
81 mg, for MI, CVA, pts with prosthetic valves, and stents
NO ANTIDOTE
how does abciximab work, and when is it used
glycoprotein antagonist prevents binding of fibrinogen, stopping platelet aggregation
for interventional procedures with aspirin and heparin
how does cilostazol work and when is it used
phosphodiesterase inhibitor inhibits platelet aggregation and causes vasodilation
-used for intermittent claudication– pain caused by PAD/PVD
-know it is caused by this if it is relieved by rest
should improve within 2-4 weeks up to 12 weeks
how does anagrelide work and when is it used
inhibits platelet aggregation induced by CAMp, phosphodiesterase, ADP, and collagen.
used to reduce platelet counts – thrombocythemia
when are thrombolytic agents used
only in emergencies, large risk/benifit
what labs are needed for thrombolytics
INR, aPTT, platelet count, fibrinogen
how does alteplase work and when is it used
recombinant plasminogen activator
used for: post CVA, massive PE
side effects to alteplase and other thrombolytics and when should it not be used
SYSTEMIC BLEEDING, kidney and liver function
-intracranial/spinal surgery
-severe hypotension
-active bleeding/coagulation issues/anticoagulation meds
-recent surgery
-stroke aneurysm in last 2 months