Wed - goueli - coagulation Flashcards
Pentad of TTP and how do you Dx and Tx
microangiopathic hemolytic anemia, thrombocytopenia, fevers, renal failure, neurologic deficits. Pts may not have secondary Sx, maybe only the first two.
Dx by doing a peripheral smear and looking for schistocytes
Tx by giving fresh frozen plasma via plasma electrophoresis to replenish the ADAMTS13
he didn’t say it’s on the test, but he had a huge boner for it.
What are the intrinsic and extrinsic pathways of clotting
intrinsic pathway - factors 12,11,9,8
extrinsic - factor 7, tissue factor, used to convert 10 to 10a so you can generate thrombin so you can generate fibrin (common pathway)
mech of warfarin (coumadin)
what drug do you give with it when you start and why
how do you reverse it
It blocks vitamin K reductase enzymes used to regenerate active vitamin K
(stops gamma carboxylation of glutamate residues in factors II, VII, IX, X, and proteins C and S - the fact that it reduces C and S is why when patients are initially put onto coumadin they have an increased chance of clotting - to stop this you give lovenox (low MW heparin) with it at first)
reverse it by giving vitamin K
if someone is clotting like crazy and there is no obvious reason, what is the first thing you should look for
deficiency in antithrombin III
deficiency in protein c and protein s
factor 5 ligand deficiency - factor 5a is abnormal, and not degraded by activated protein c
mech of TPA
tissue plasminogen activator
plasminogen is converted to plasmin, which degrades fibrin and busts up clots
What factors require vitamin K dependant gamma carboxylation in order to work optimally
2,7,9,10,c,s
mech of heparin, how do you reverse it
binds to and increases the activation of antithrombin III, which inhibits factor VIIIa, IXa, Xa, XIa, and inhibits thrombin
give protamine to reverse
does aspirin irreversably inhibit platelets by irreversably inhibiting COX?
yea, and its on the test
What does vWF do?
vWF acts as a bridge between a specific glycoprotein complex on the surface of platelets (GPIb-GPIX-GPV) and collagen fibrils on damaged tissues
