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Flashcards in Drugs used in Coagulation Disorders Deck (76):
1

Drugs used in clotting/bleeding disorders fall into two categories

1. drugs used to decrease clotting or dissolve clots already present
2. drugs used to increase clotting in patients at risk of a bleed

2

Anticoagulants are used for

1. acute MI
2. A-fib
3. Ischemic stroke
4. DVT

3

anticoag drugs and thromoboylitic drugs are effective againt

arterial and venous thrombi

4

antiplatelet drugs are used against

arterial thrombi only

5

List the categories of anticoagulants

heparins, direct thrombin inhibitors, direct Xa inhibitor, warfarin

6

name the thrombolytics

urokinase, TPA derivatives

7

name the antiplatlet drugs

aspirin, glycoprotein IIb/IIIa inh., ADP inihibitors, pde uptake inhibitors

8

dosage route of heparin

parenterally (IV or subQ)

9

dosage route of coumadin

oral

10

dosage route of thrombin/X inh

parenteral or oral

11

antidote to heparin

protamine
works well on unfract. hep, partially on LMWH and not at all on Fondaparinux

12

Advantages of LMWH

*more specific for ATIII and not II
greater F
longer duration
lower chance of HIT

13

example of a LMWH

enoxaparin sodium

14

heparin like products are measure

by APTT

15

APPT used to measure

effect of heparin and direct thrombin inhibitors

16

Antithrombin II inactivates

thrombin, X, 9, 11

17

Heparin MOA

increases ATIII's activity by 1000 fold

18

GPIIb/IIIa is activated by

platelet release of ADP, TXA2, and serotonin--> cause upreg of GP2b3a on platelet surface

19

How does HIT happen

more common with unfractionated heparin--> IgG ab to PF4-Heparin complex--> results in marked thrombocytopenia

20

will APTT measure LMWH

no

21

Can heparin be used in pregnancy

yes--> does not cross placenta

22

Fondaparinux

mimics the bioactive pentasaccharide on heparin--> same effects, given sub Q once a day

23

onset of heparin

instant (minutes)

24

excretion of heparin

renal

25

choice anticoag during pregnancy

heparin

26

site of action for heparin

blood

27

site of action for coumadin

liver

28

onset of coumadin

slow--> days 10 mg 5 mg 5 mg--> then recheck INR--> decide what to do from there

29

protein C inhibits

factors 5 and 8

30

cleaved by thrombin

1, 5, 8, 11, 13

31

common uses of heaprin

ACUTE
PE, MI, DVT

32

prolonged use of unfractionated heparin is associated with

osteoporosis

33

inibited by heparin

11, 8, 5, *accoriding to the book

34

inhibited by coumadin

2, 7, 9, 10 c, s

35

Direct thrombin inhibitors
administered parenterally

Lepuridin
Desirudin
bivalirudin
argotroban

36

direct thrombin inhibitors
administered orally

Dabigatran

37

MOA of Lepuridin

bind simulatenously to the acitve site of thrombin and thrombin substrates

38

MOA of Argatroban

binds only the thrombin active site

39

reversal agents for dorect thrombin inhibitors and direct Xa inhibitors

none

40

Direct thrombin inhibitor that can also inhibit platelets

Bivalirudin

41

how do you monitor coumadin

PT--> turn it into INR

42

INR range for someone who needs coumadin

2-3

43

INR range for someone with persistent dvt

2.5-3.5

44

antidote for coumadin toxicity

vitamin K, FFP, prothombin complexes

45

MOAS for coumadin

inhibits Vitamin K epoxide reductase preventing Vit K from being replenished and therefore GAMMA carboxylation cannot occur for factors 2, 7, 9, 10 C or S

46

Direct Xa inhibitors

rivaroxaban
apixaban

47

do Direct Xa or Direct thrombin inhibitors require monitoring

no

48

preferred anticoagulant in pt.s with HIT

direct thrombin inhibitors

49

Rivaroxaban indication

pt.s undergoing hip/knee replacement and prevention of stroke for Afib pt.'s

50

Warfarin in the circulation

99% bound
*anything that causes it to come unbound will have a major impact

51

Warfarin broekn down in the liver by

CYP2C9

52

can coumadin be used in pregnant women

no

53

necrosis due to warfarin toxicity is due to

acute deficiency of factor C

54

inducers of CYP--> causing low coumadin and therefore hypercoaguability

rifampin, phenytoin, and barbituates

55

inhibitors of CYP causing warfarin to be too low--> blled risk

SSRI's, cimetidine

56

explain INR

inr= patients test PT/ standard PT (12-13)

57

high INR=

pt is more anticoagulated than a "normal" person and at a risk for bleed *their pt is long=slow clot

58

low INR=

pt is hypercoagulated and at a risk thrombus
*their pt time is quick=fast clotter)

59

Thrombolytic agents

T-PA (alteplase)
streptokinase (protein made by streptococci)

60

Thrombolytic enzymes MOA's

catalyze the cleavage of plasminogen to plasmin so it can cleave fibrin and free serum fibrinogen--> dissolving and preventing a clot

61

seletivity of TPa

only cleaves plasminogen when bound to fibrin (but selectivity is less than you would hope for)

62

streptokinase MOA

does not cleave plasminogen directly-->forms a complex with plasminogen and causes it to undergo conf. change where it is cleaved rapidly by normal TPA

63

does streptokinase show selectivity for fibrin

no

64

most important indication of thrombolytic agents

as an alternative to percuatenous coronary angioplasty in emergency tx of coronary artery thrombosis with 6 hours
*also Stroke if within 3 hours
*also severe PE

65

name the antiplasmin drugs

tranexamic acid and aminocaproic acid

66

side effect specific to streptokinase

those with prevoius infection to the bacteria may have ab's specific for the drug--> immune response

67

major adverse event you're concerned with about thrombolytic agents

cerebral hemorrhage and bleeding

68

how does PGI2 (prostacylin) inihibit platelet aggregation

increases cAMP which dereases free calcium levels--> this will inihibit platelet aggregation

69

Antipletelet drugs include

1. aspirin and other NSADS (not tyelenol)
2. GP2b3a inh, abciximab, tirofiban,
3. ADP antagonists (clopidogrel)
4. Phosphodiesterase inh. (dipyramidole)

70

dipyramidole MOA

prolong the platelet inhibiting action of cAMP by inhibiting phosphodesterase (which breaks down cAMP)--> Ca2+ stays low and pletelets dont aggregate
*increases cGMP levels--> a vasodilator
*inhibit the uptake of Adenosine--> increase plasma concentration of adenosine

71

Drug used to treat vitamin K deffieiency

phytonadione

72

most important agents to treat hemophillia A/B

FFP, and factor 8 (A), 9 (B)

73

increases plasma concentration of vWF

desmopressin and factor 8

74

when do you use desmopressin

hemophilia A or to prepare pt.'s non vW disease for elective surgery

75

antiplasmin agents do what

increas clotting for the prevention of acute bleeding apirsodes in patients with hemophillia and others with high risk of bleeding disorders

76

name he antiplasmin meds

aminocaproic acid and tranexamic acid