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Flashcards in Coagulation Deck (42)
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1
Q

3 steps of hemostasis

A

vasospasm
platelet plug fomation
coagulation

2
Q

hemostasis

A

the ability to minimize blood loss

3
Q

vasospasm

A

vasoconstriction

4
Q

4 steps of platelet plug formation

A
  1. adhesion
  2. platelet activation
  3. platelet aggregation
  4. platelet plut
5
Q

vonWillebrand factor (vWH)

A

holds platelets up to the exposed collagen

6
Q

platelet activation

A

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

7
Q

platelet aggregation

A

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

8
Q

prostacyclin

A

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

9
Q

factor XII

A

activated when surface contact-turns into activated 12a

10
Q

what is thrombin’s key function?

A

turn fibrinogen into fibrin (active form)

11
Q

fibrinolysis

A

breakdown of a clot and resorbtion of the clot

12
Q

plasmin

A

enzyme responsible for the breakdown of fibrin

13
Q

normal platelet count

A

150,000-450,000/ uL

-not a measure of function

14
Q

why is the patient bleeding?

A

platelet?

coagulation?

15
Q

platelet bleeding problems may be seen with

A

petechiae, ecchymosis or purpura

16
Q

thrombocytopenia

A

low platelet count

17
Q

reasons why platelets may not be working

A

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

18
Q

bleeding test

A

BT (higher it is, the longer you bleed)

-not used anymore

19
Q

normal range PT (prothrombin time)

A

13-17 seconds

20
Q

what does the PT measure?

A

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

21
Q

increased PT time values may indicate

A

vitamin K deficiency and liver disease

22
Q

vitamin K deficiency can be caused by

A

bile duct obstruction

malabsorption

23
Q

liver disease affects coagulation in that

A

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

24
Q

normal values for the aPPT

A

25-36 seconds

25
Q

what does the aPPT measure?

A

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

26
Q

what conditions would cause a prolonged aPPT?

A
hemophilia A (missing factor 8)
hemophilia B (missing factor 9)
biliary obstruction (no vitamin K absorbed)
hepatocellular diseases
27
Q

normal ranges for fibrinogen

A

150-350 mg/dl

28
Q

what is fibrinogen used for?

A

diagnose fibrinogen disorders or inhibitors of thrombin

-also to diagnose problems with fibrinolysis

29
Q

when might fibrinogen be increased?

A

tissue inflammation

30
Q

normal ranges of TT (thrombin time)

A

15-18 seconds

-measures common pathway

31
Q

tissue factor pathway inhibitor

A

acts on the common pathway to control the clot

32
Q

bleeding differential diagnosis

A
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
Q

vonWillebrands disease

A

most common inherited congenital bleeding disorder

-clinical presentation is bleeding (nasal, sinus, vaginal, GI, deep tissue bleeding)

34
Q

what other factor is related to the vWF?

A

factor VIII

35
Q

how is DDAVP used?

A

treat VWD (stimulates release vWF)

36
Q

hemathrosis

A

main symptom of hemophilia

-hematoma of the joints

37
Q

expected lab results for hemophilia

A

aPPT will be high

PT will be low

38
Q

FDP

A

fibrinogen degradation products

39
Q

how does aspirin prevent clotting?

A

kills platelet function for the life of the platelet

40
Q

how do NSAIDS prevent clotting?

A

deactivate platelet, but function returns w/in 24 hours

41
Q

what is the main symptom of hemophilia a or b?

A

hemarthrosis

42
Q

what are the causes of hypercoagulability?

A

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

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