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Flashcards in Coagulation Deck (42):
1

3 steps of hemostasis

vasospasm
platelet plug fomation
coagulation

2

hemostasis

the ability to minimize blood loss

3

vasospasm

vasoconstriction

4

4 steps of platelet plug formation

1. adhesion
2. platelet activation
3. platelet aggregation
4. platelet plut

5

vonWillebrand factor (vWH)

holds platelets up to the exposed collagen

6

platelet activation

platelets release chemical messages to get more platelets to come (ADP, seratonin, thromboxane, A2)

7

platelet aggregation

a bunch of platelets come together to plug up the exposed area

8

prostacyclin

secreted by neighboring, healthy cells so that platelets only aggregate in the correct area

9

factor XII

activated when surface contact-turns into activated 12a

10

what is thrombin's key function?

turn fibrinogen into fibrin (active form)

11

fibrinolysis

breakdown of a clot and resorbtion of the clot

12

plasmin

enzyme responsible for the breakdown of fibrin

13

normal platelet count

150,000-450,000/ uL
-not a measure of function

14

why is the patient bleeding?

platelet?
coagulation?

15

platelet bleeding problems may be seen with

petechiae, ecchymosis or purpura

16

thrombocytopenia

low platelet count

17

reasons why platelets may not be working

aspirin
uremia
genetic disorders (rare)
vWF (can't bind without it)

18

bleeding test

BT (higher it is, the longer you bleed)
-not used anymore

19

normal range PT (prothrombin time)

13-17 seconds

20

what does the PT measure?

extrinsic and common pathways
(5, 7, 10, 2 and 1)
-INR (intl normalized ratio)
-used to monitor coumadin

21

increased PT time values may indicate

vitamin K deficiency and liver disease

22

vitamin K deficiency can be caused by

bile duct obstruction
malabsorption

23

liver disease affects coagulation in that

vitamin K is used by the liver to make the clotting factors and bile salts are also used and formed in the liver

24

normal values for the aPPT

25-36 seconds

25

what does the aPPT measure?

intrinsic and common pathway
(12, 11, 9, 8, 10, 5, 2, 1)
-used to monitor heparin therapy

26

what conditions would cause a prolonged aPPT?

hemophilia A (missing factor 8)
hemophilia B (missing factor 9)
biliary obstruction (no vitamin K absorbed)
hepatocellular diseases

27

normal ranges for fibrinogen

150-350 mg/dl

28

what is fibrinogen used for?

diagnose fibrinogen disorders or inhibitors of thrombin
-also to diagnose problems with fibrinolysis

29

when might fibrinogen be increased?

tissue inflammation

30

normal ranges of TT (thrombin time)

15-18 seconds
-measures common pathway

31

tissue factor pathway inhibitor

acts on the common pathway to control the clot

32

bleeding differential diagnosis

CALFDIPS
cirrhosis and coumadin
aspirin
leukemia
factor definciency (hemophilia)
disseminated intravascular coagulopathy
idopathic thrombocytopenic purpura (ITP)
platelet deficiency or dysfunction
scurvy-vitamin C deficiency

33

vonWillebrands disease

most common inherited congenital bleeding disorder
-clinical presentation is bleeding (nasal, sinus, vaginal, GI, deep tissue bleeding)

34

what other factor is related to the vWF?

factor VIII

35

how is DDAVP used?

treat VWD (stimulates release vWF)

36

hemathrosis

main symptom of hemophilia
-hematoma of the joints

37

expected lab results for hemophilia

aPPT will be high
PT will be low

38

FDP

fibrinogen degradation products

39

how does aspirin prevent clotting?

kills platelet function for the life of the platelet

40

how do NSAIDS prevent clotting?

deactivate platelet, but function returns w/in 24 hours

41

what is the main symptom of hemophilia a or b?

hemarthrosis

42

what are the causes of hypercoagulability?

too many platelets
vascular injury
clotting factors not working properly (anticlotting factors)
stasis and surgery

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