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Board Review CRNA (Sweat Book) > Hemostasis > Flashcards

Flashcards in Hemostasis Deck (104)
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61

Massive transfusion is defined as ___________.

one complete blood volume transfused within 24 hours

62

What is the role of antithrombin?

it binds thrombin (factor IIa) and factor Xa GREATLY
it binds IX, XI, and XII to a LESSER extent
removes them from circulation--> anticoagulating the blood

63

How does heparin work?

increases the effectiveness of antithrombin 1,000 fold or more

64

Where is antithrombin made?

the liver

65

Heparin binds to _______.

antithrombin III

66

Heparin increases the rate of thrombin-antithrombin reaction by _______.

1000 fold or more

67

Name 2 disease processes that can cause an acquired antithrombin deficiency state.

1) cirrhosis of liver
2) nephrotic syndrome

68

What is the MOST common reason a patient can be unresponsive to heparin?

b\c they have an antithrombin deficiency

69

What is the appropriate ACT result indicating that a patient has been adequately heparinized before a CABG?

>400s
if the ACT is low you can give FFP because FFP contains all coagulation and anticoagulation factors made by the liver--> including antithrombin

70

What pathway or pathways does heparin block?

classical intrinsic and final common pathway

71

What is the reversal for heparin?

protamine

72

How does protamine work to reverse heparin?

it is a positively charged substance that combines electrostatically with heparin, a negatively charged substance--> this is a neutralization reaction

73

Protamine reverses the action of heparin by ______.

neutralization

74

Warfarin (coumadin) binds to ______ receptors in the ______.

vitamin K receptors in the liver---> production of vit K dep factors (II, VII, IX, X) is depressed

75

What pathway is blocked with warfarin?

classical extrinsic and final common pathways

76

Recombinant hirudin, ximelagatran, and argatroban are direct _____ inhibitors.

thrombin

77

What two tests assess heparin?

PTT and ACT

78

Heparinization is adequate if the ACT is > _______ sec.

400-450 sec

79

What is the normal value? bleeding time

3-10min

80

What is the normal value? platelet

150-400,000 cells/ml

81

What is the normal value? prothrombin time (PT)

12-14 sec

82

What is the normal value? activated partial thromboplastin time (PTT)

25-35 sec

83

What is the normal value? activate coagulation time (ACT)

80-150sec

84

_______ is the body's clot buster.

plasmin

85

How does plasminogen (inactivated form of plasmin) get converted into plasmin? (2)

tpa and upa
tissue type plasminogen activator
urokinase type plasminogen activator

86

When a clot is formed, what is there all along that will assist in the destruction of the clot at a later time?

plasminogen is incorporated into the clot as it is formed

87

Plasminogen, the inactive form of plasmin, is synthesized in the ________ and circulates in the blood.

liver

88

Where is TPA made and what is its role?

its made in endothelial cells---> released when needed to convert plasminogen into plasmin

89

Aprotinin and Amicar (epsilon aminocaproic acid) work by _______.

inhibiting plasmin

90

When plasmin is inhibited, fibrin that is formed breaks down _______, so bleeding is _______.

slowly; decreased