coagulation

Question 1

what are the key mediators of endothelial damage ?

Answer 1

endothelins - cause vasocontriction

Question 2

what are the active forms of coagulation factors called ?

Answer 2

serine proteases

Question 3

what is the centre of the coagulation cascade ?

Answer 3

activation of factor 10 into factor 10 a

Question 4

what happens after the activation of factor 10 ?

Answer 4

changes prothrombin 2 to thrombin 2a

then thrombin converts fibrinogen into fibrin

Question 5

what are the factor 5a inhibitors drugs and what is the end result ?

Answer 5

apixaban
rivaroxaban
they inhibit thrombin formation

Question 6

what is the end result associated with inhibiting factor 2 a ?

Answer 6

decreased fibrin formation

Question 7

what activates factor 10 3amatan ?

Answer 7

tissue factor , which is found in sub endothelial cells , so only released when endothelial damage happens

Question 8

after the activation of tissue factor what happens ?

Answer 8

tissue factor activates factor 7 to make it 7a
then 7a activates 10 a

Question 9

how does thrombin make more thrombin ?

Answer 9

positive feedback factor 9a men el a5er can activate factor 10 to restart the whole clotting cascade

Question 10

what are the clotting factors deficiencies with hemophilia ?

Answer 10

hemophilia A : def factor 8
hemophilia B : def factor 9
Hemophilia C : def factor 11

Question 11

where is factor 8 produced ?

Answer 11

in the endothelial cells

Question 12

what is the association between factor 8 and von willebrand disease?

Answer 12

inactive form of factor 8 is bound to VWF to increase its plasma half life

Question 13

what co factors are needed for the activation of factor 10 ?

Answer 13

phospholipid and calcium

Question 14

what are the two multicomplement pathways associated with the activation of factor 10 ?

Answer 14

TF:VII a
IXa: VIIIa

Question 15

what is the function of factor 13 ?

Answer 15

crosslinks fibrin

Question 16

what happens if there is a defeciency in factor 13 ?

Answer 16

inadequate clot formation

Question 17

what does factor 13 need to work ?

Answer 17

calcium as a co factor

Question 18

what is factor 13 activated by ?

Answer 18

thrombin 2a formation

Question 19

what is the other name for factor 12 ?

Answer 19

also called factor hageman

Question 20

what is the function of factor 12 ?

Answer 20

activates factor 11

Question 21

what activates factor 12 ?

Answer 21

contact with negative charges like silica

Question 22

what is the function of the PTT test ?

Answer 22

tests the intrinsic pathway

Question 23

what are the main 2 pathways that fibrin can be made ?

Answer 23

either by the tissue factor pathway
or by the factor 12 pathway

Question 24

what is the difference between the intrinsic and the extrinsic pathway ?

Answer 24

the one that starts with tissue factor is the extrinsic pathway
the one that starts with factor 12 is the intrinsic pathway

Question 25

how is the intrinsic pathway tested vs the extrinsic pathway ?

Answer 25

intrinsic is tested with the PTT the extrinsic is tested by the PT where we add TF to the plasma

Question 26

what are the requirements for the activation of the intirinsic pathway ?

Answer 26

kinins , which circulate s inactive kininogens

Question 27

what is the purpose of the kinins ?

Answer 27

these are the connections between inflammation and coagulation through factor 12

Question 28

what is the most important factor of the kinin system ?

Answer 28

bradykinin

Question 29

what are the clinical associations with bradykinin ?

Answer 29

bradykinin aslan is a vasodilator , that is degraded by ACE , which raises the levels of bradykinin which may lead to angioedema

Question 30

what are the cases that are contraindicated with ACE use ?

Answer 30

hereditary angioedema ( C1 inhibitor defeciency )

Question 31

which of the factors is associated with the formation of kinins ?

Answer 31

factor 12

Question 32

what are the 2 co factors needed in order to activate factor 12 to make bradykinins ?

Answer 32

1- activated factor 12 converts prekallikrein to kallikrein 2- kallikren converts HMWK to bradykinin

Question 33

what are the effects of prekallikren deficiency ?

Answer 33

results in prolonged PTT but no bleeding problems because of the low significance of it as a clotting factor

Question 34

what are the natural inhibitors of the coagulating system ?

Answer 34

antithrombin 3 protein C and S tissue factor pathway inhibitor

Question 35

what does antithrombin 3 inhibit ?

Answer 35

factor 2 , 7 , 9, 10 , 11 , 12

Question 36

what does a deficiency of these natural anticoagulants cause ?

Answer 36

hypercoaguable state

Question 37

what does protein C inhibit ?

Answer 37

factor 5a and factor 8a

Question 38

what is protein C activated by ?

Answer 38

thrombomodulin which is found on endothelial cells , so endothelial cells produce a good amount of protein C

Question 39

what is the co factor for the function of protein C ?

Answer 39

protein S

Question 40

what does tissue factor pathway inhibitor inhibit ?

Answer 40

inactivates 10 a

Question 41

what is the clinical relevance of TFPI ?

Answer 41

the plasma levels of it are increased with heparin administration

Question 42

what helps break down a clot when it is made ?

Answer 42

plasminogen and plasmin they break down fibrin

Question 43

what are the natrual plasminogen activators ?

Answer 43

these are chemicals that help activate plasminogen in oder to increase the breakdown of fibrin and clots tPA and urokinase

Question 44

what are the clinical uses of the plasminogen activators ?

Answer 44

tPa and urokinase are used to breakdown clots in MI and stroke streptokinase is used

Question 45

once plasmin breaks down the fibrin what are the end products ?

Answer 45

1- fibrin degradation products 2- d dimer

Question 46

what does the presence of d dimer in the plasma mean ?

Answer 46

that means that there is a breakdown of clots in the blood by plasminogen

Question 47

what is an elevated d dimer used for ?

Answer 47

to diagnose DVT and PE

Question 48

what is primary fibrinolysis ?

Answer 48

overactivity of plasmin where there is a rise in FDP with a normal d dimer level

Question 49

what effect does plasmin have on the clotting factors ?

Answer 49

can deplete them

Question 50

what are the diseases associated with primary fibrinolysis ?

Answer 50

prostate cancer - due to an increase in urokinase cirrohsis - loss of antiplasmin from the liver

Question 51

what is the difference in lab values between hyperfibrinolysis and clot breakdown ?

Answer 51

hyperfibrinolysis - FDPs with normal D dimer levels clot breakdown - increase in both FDPs and d dimer

Question 52

what are the vitamin k dependant factors ?

Answer 52

2 , 7 , 9 , 10 , protein C and S

Question 53

what is the MOA of warfarin ?

Answer 53

vitamin K antagonist

Question 54

what are the key acute phase reactants ?

Answer 54

fibrinogen ferritin CRP