clotting cascade and drugs Flashcards
(39 cards)
arterial thrombus
white thrombus: platelets in fibrin mesh
arterial thrombus treatment
antiplatelet
venous thrombus
red thrombus
venous thrombus Treatment
anticoagulants
what does the extrinsic pathway start with
TF
what does the intrinsic pathway start with
XII
what converts prothrombin to thrombin
Xa
what converts fibrinogen to fibrin
thrombin
what converts plasminogen to plasmin
tPA
what is warfarin structure similar to
vitamin K
warfarin action
blocks vit K dependent gamma carboxylation of glutamate residues
results in the production modified factors VII, IX, X and prothrombin (factor II)
what is used to monitor warfarin dosage
prothrombin time
how long does warfarins full effect take
4-5 days
what must you do with warfarin if you require an immediate effect
use heparin
warfarin therapeutic index
low
factors that potentiate warfarin (inc risk of haemorrhage)
liver disease
high metabolic rate
factors that lessen warfarin action (risk of thrombosis inc)
pregnancy or hypothyroidism
vitamin K consumption
warfarin overdose
stop drug and give vitamin K (oral phytomenadione)
heparin action
activates antithrombin III
what does antithrombin III do
inhibit thrombin, factor Xa and IXa/tenase
LMWH action
inhibits Xa
LMWH example
dalteparin
LMWH half life in comparison to heparin
longer
LMWH dosage
daily dose by SC injection
