Coagulation 5

Question 1

Heparin inhibits the:
a. extrinsic pathway
b. intrinsic pathway
c. extrinsic and final common pathways
d. intrinsic and final common pathways

Answer 1

d. intrinsic and final common pathways

Question 2

Heparin inhibits the:
a. extrinsic pathway
b. intrinsic pathway
c. extrinsic and final common pathways
d. intrinsic and final common pathways

Answer 2

d. intrinsic and final common pathways

Question 3

Heparin inhibits the

Answer 3

intrinsic and final common pathways

Question 4

Heparin binds to ___________

Answer 4

antithrombin (& accelerates its anticoagulant ability by 1000)

Question 5

The heparin-AT complex neutralizes

Answer 5

thrombin 2a and factors 9a, 10a, 11a, and 12a
& platelet function

Question 6

Dosing of heparin for cardiac surgery is

Answer 6

300-400 U/kg

Question 7

VTE prophylaxis of heparin is

Answer 7

5,000 U SC BID or TID

Question 8

The unstable and acute MI dose of heparin is

Answer 8

5,000 U IV then infusion of 1,000 U/hr

Question 9

Side effects of heparin include

Answer 9

hemorrhage & heparin-induced thrombocytopenia
allergic reaction
hypotension
decreased antithrombin concentrate

Question 10

Heparin should not be used with

Answer 10

neurologic procedures
HIT
regional anesthesia

Question 11

Heparin is reversed with

Answer 11

1 mg of protamine for every 100 units of heparin

Question 12

The risk of protamine allergy is increased in patient’s who’ve

Answer 12

been sensitized to NHP insulin or have a fish allergy

Question 13

Failed heparinization should prompt consideration of

Answer 13

AT deficiency

Question 14

What is the volume of distribution of heparin?

Answer 14

small

Question 15

How is heparin metabolized?

Answer 15

by heparinase

Question 16

What are the pathways for elimination of heparin?

Answer 16

Degradation by macrophages & renal excretion

Question 17

Can heparin be given to the parturient?

Answer 17

yes, it does not cross the placenta

Question 18

Therapeutic heparinization occurs when

Answer 18

aPTT is 1.5-2.5 times normal

Question 19

ACT is affected by

Answer 19

hypothermia
thrombocytopenia
deficiency of fibrinogen, factor 7, or factor 12

Question 20

How is heparin’s anticoagulant activity stopped with protamine?

Answer 20

the positive charge of protamine and the negative charge of heparin create a neutralization reaction that stops heparin’s anticoagulant activity

Question 21

_____________ clears the heparin-protamine complex

Answer 21

The reticuloendothelial system

Question 22

When given alone, protamine is a

Answer 22

anticoagulant

Question 23

Side effects of protamine include

Answer 23

hypotension
pulmonary hypertension
allergic reaction

Question 24

Why does hypotension occur with protamine?

Answer 24

due to histamine release

Question 25

Why does pulmonary hypertension occur with protamine?

Answer 25

TxA2 and serotonin release

Question 26

Where is endogenous heparin produced?

Answer 26

liver, basophils, and mast cells

Question 27

Warfarin inhibits factors:
a. 3 & 10
b. 2, 7, 9, & 10
c. 2, 7, 9, 10, and protein C
d. 2, 7, 9, 10, protein C and protein S

Answer 27

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

Question 28

Warfarin inhibits

Answer 28

vitamin K

Question 29

The target PT value for a patient on warfarin therapy is

Answer 29

2-3 timex normal

Question 30

Warfarin can be reversed with

Answer 30

FFP (fast) or vitamin K (slow-not good for emergent reversal)

Question 31

Vitamin K is a _________ vitamin that requires the presence of __________ for absorption

Answer 31

fat-soluble; fat & bile

Question 32

Vitamin K deficiency produces

Answer 32

coagulopathy

Question 33

Vitamin K supplementation requires

Answer 33

a function liver

Question 34

Vitamin K supplementation requires ___________ to restore the concentration of vitamin K dependent clotting factors in the blood.

Answer 34

4-8 hours

Question 35

IV administration of vitamin K is associated with

Answer 35

life-threatening anaphylaxis

Question 36

If vitamin K is given via the IV route, the rate should not exceed

Answer 36

1 mg/min

Question 37

Warfarin is _____________________ protein bound

Answer 37

highly

Question 38

Warfarin requires ___________- to achieve a therapeutic concentration

Answer 38

36-72 hours

Question 39

For emergent or high-risk procedures, such as intracranial procedures, warfarin should be reversed with

Answer 39

FFP (1-2 units)
recombinant factor 7a
prothrombin complex concentrate

Question 40

These can impair fat absorption and therefor produce vitamin K deficiency

Answer 40

malabsorptive disease and decreased bile production

Question 41

Risk factors for vitamin K deficiency include

Answer 41

poor dietary intake
malabsorption due to obstructive biliary tract disease
hepatocellular disease
abx therapy kills off the GI flora and reduces bacterial synthesis of vitamin K
Neonates do not have the intestinal flora that synthesizes vitamin K

Question 42

_________ is another name for exogenously administered Vitamin K

Answer 42

phytonadione

Question 43

The dose of Vitamin K is

Answer 43

10-20 mg PO, IM, or IV

Question 44

Where do we obtain inactive vitamin k?

Answer 44

diet
manufactured in the gut via bacteria

Question 45

How does warfarin work?

Answer 45

it inhibits vitamin K epoxide reductase complex 1 (an enzyme) which indirectly inhibits production of vitamin-K dependent factors