thrombosis Flashcards
if you have a peripheral arterial thrombosis what is it called
gangrene
what is the biggest risk factor for a DVT
previous one
what type of clots are seen in the arterial system
platelet rich
what drugs are used in arterial clots
aspirin and anti-platelet
are platelets activated in venous clots ?
no as no endothelial damage
what type of clots seen in venou ssytem
fibrin rich
what causes venous clots
valve degeneration
treatment of venous clots
heparin, warfarin, DOAC
what is given in acute VTE
heparin - immediate action
what us the annual risk of a vte
1/1000
young 1/10,000
old 1/100
symptoms of VTE
pitting oedema, swelling , red ,tender
examples of hereditary thrombophilias
factor V Leiden prothrombin 20210 mutation anti-thrombin deficiency protein S deficiency protein C Deficiency
name an acquired thrombophilia
anti-phospholipid syndrome
what is more likely to casue clot inherited or acquired thrombophilia
acquired anti-phospholipid
what is prolonged in anti-phospholipid APTT or PTT
APTT
treatment of anti-phospholipid syndrome
aspirin and warfarin as both venous and arterial clots seen
what clot do heparin and warfarin target
fibrin clot - venous system
indications for anti-coagulants
VTE or AF
action of heparin
potentiates anti-thrombin
how is heparin delivered
IV or SC
how does unfractionated heparin work
inactivating thrombin and activated factor X (factor Xa) through an antithrombin (AT)-dependent mechanism
how does LMWH work
binds to anti-thrombin and creates a conformational change. This change accelerates its inhibition of activated factor X
what should be used for monitoring heparin and LMWH respectively
heparin - APTT
LMWH - Factpr Xa assay - monitoring not rquired
side effects of heparin
bleeding
induced thrombocytopenia
osteoporosis long term
how to reverse heparin
stop heparin
protamine sulphate
what class of anticoagulant is warfarin
coumarin anticoag
what must be given alongside warfarin at initiation
heparin
how is warfarin delivered
Oral
mechanism of action of warfarin
Vitamin K inhibitor
why does heparin need to be given alongside warfarin at intitiation
warfarin inhibitd vitamin K which carboxylases protein c and s so transient increase in clotting chance at beginning
when shoudl warfarin be taken
same time everyday 6pm recommended
what is used to monitor warfarin
PTT as factor 7 most sensitive
how is warfarin metabolised
by CYP450 in liver
side effects of warfarin
bleeding
lots of interactions
what do you do if INR too high on warfarin
vit k admin
what is dabigatran
oral direct thrombin inhibitor
how is dabigatrann excreted
renally
give examples of oral Xa inhibitors
apixaban , rivaroxiban , edoxaban
mechanism of action for aspirin
cox inhibtior - cox makes thromboxane A 2
side effects of aspirin
bleeding
GI ulcer
brnchospasm - not in asthma
mechanism of action for clopidergrel
ADP receptor antag - P2Y12 receptor
what receptors do platelets bind to in aggregation
GPIIb, IIa (abciximab - an inhibitor of this used prior to surgery)
