coagulation Flashcards
ability of the blood stop bleeding
hemostasis
wall defect in endothelial causes what to factors to be exposed
collagen
von willebrand factor
formation of a clot term
thrombogenesis
red thrombus
veins
RBC
long fibrin tail
detach -> PE/DVT
white thrombus
arterial flow
platelets and fibrin cross-linking
glycoproteins on platelet cell surfaces
name and what they bind to
collegen binds to glycoprotein 1a receptor
vWF binds to glycoprotein 1b receptor
3 soluble mediators in platelet activation
adenosine (ADP)
thromboxane A2
serotonin (5HT)
what do NSAIDS inhibit
prostaglandin synthesis
- pro-clot
- black box for CV events
what does aspirin target
inhibits thromboxane A2
what do endothelial cells normally produce
prostaglandin I2 (prostacyclin)
inhibits platelet aggregation
extrinsic pathway activation
outside tissue damage exposes tissue factor
intrinsic pathway activation
inside the vessel
platelets interact with damaged endothelium
DVT Virchow’s Triad
- stasis
- hyper coagulability
- endothelial injury
inherited DVT risk factors
antithrombin III deficiency (normally inhibits thrombin from forming)
Protein C and S deficiency (inhibit factor 8)
sickle cell anemia (RBC become trapped and damage endothelium)
activated protein C resistance (normal amount of protein C but factors produced are resistant)
acquired DVT risk factors
bedbound, surgery, trauma, obesity, estrogen malignancies, chronic venous insufficiency.
DIC
what is it
disseminated intervascular coagulation
- using up all clotting factors and platelets
what causes DIC
- gram (-) bacteria b/c of endotoxins it releases
- massive tissue injury
- malignancy
- abruptio placentae
protease inhibitors
what they do?
list 4 of them
inactivate the coagulation proteins
alpha 1 antiprotease
alpha 2 macroglobulin
alpha 2 antiplasmin
antithrombin
what breaks down the clot after its formed?
inactive plasminogen -> plasmin
activated by tissue plasminogen activator (tPA)
- plasmin breaks down the fibrin
intrinsic pathway numbers
12, 11, 9, 10
extrinsic pathway numbers
7, 10
common pathway
prothrombin -> thrombin
fibrinogen -> fibrin
what factors does thrombin activate? (5)
factor 13
factor 5
factor 8
factor 11
protein C
hemophilia type A is what clotting factor
8
3 activators of plasminogen -> plasmin
fibrinolytics
- pro-bleeding
- catalyze formation of serine protease plasmin
- tissue plasminogen activator (tPA)
- Urokinase
- Streptokinase
what makes up anistreplase
pro-activator + streptokinase
= activator
2 drugs protect clots from lysis
inhibit plasminogen -> plasmin
aminocaproic acid
TXA
HIT
what is it?
treatment?
antibodies target thrombocytes (decrease platelets)
stop drug
platlets, FFP
7-10 days post initiation
aptt
activated partial thromboplastin time
35-45 seconds
intrinsic and common pathway
phospholipid added to induce intrinsic pathway
PT
prothrombin time
extrinsic and common pathway
addition of tissue factor 3
time to clot compared to control (INR)
INR
warfarin 2-3
3 indirect thrombin inhibitors
enhances antithrombin
HMWH: antithrombin 3 (Xa and thrombin)
LMWH: factor Xa
Fondaparinux: antithrombin
heparin reversal
how does it work?
protamine
(+) binds to heparin (-)
what complex do indirect thrombin inhibitors have?
pantasaccharide
HMWH, LMWH, fondaparinux
direct thrombin inhibitors (3)
argatroban
dabigatran
Hirudin (lab version)
warfarin MOA
blocks gamma carboxylation of several glutamate resides (clotting factors 2,7,9,10) thrombin
- vit K dependent
- oxidation and reduction reaction
- high protein binding
warfarin reversal
stop drug
vit K
FFP
factor 9
heparin toxicity (3)
hemorrhagic disorder of fetus
birth defects
cutaneous necrosis
factor 10a inhibitors (2)
rivaroxaban
apixaban
streptokinase
fibrinolytic
plasminogen -> plasmin
streptococci bacteria
urokinase
fibrinolytic
plasminogen -> plasmin
synthesized by kidney and synthetic version
t-PA
tissue plasminogen activator
fibrinolytic
alteplase
activates plasminogen that it bound to fibrin -> plasmin
aspirin
cox 1
inhibits TXA2 synthesis
plavix
irreversibly inhibit ADP receptors on platelets
abciximab
2B and 3A glycoreceptors blockers
antiplatelet
monoclonial antibody
vit K
green leafy vegetables
activity on prothrombin, factors 7,9,10
desmopressin
increase factor 8
tx: von willebrand, hemophilliaA
aminocaproic acid
competitively inhibits plasminogen activation
tranexamic acid
TXA
antifibrinolytic
inhibits plasminogen
TX: severe bleeding
what does fibrin bind to on the platelets
glycoprotein 2b and 3a
