Anticoagulants & Thrombolytics: Heparin, LMWH, fondaparinux, direct thrombin inhibitors, Xa inhibitors

Question 1

Thrombin transforms fibrinogen into

Answer 1

fibrin

Question 2

Factor II is

Answer 2

thrombin

Question 3

Factor Xa converts

Answer 3

prothrombin into thrombin

Question 4

Unfractionated heparin binds

Answer 4

antithrombin III

Question 5

The unfractionated heparin-antithrombin III complex

Answer 5

irreversibly inactivates thrombin and factor Xa

Question 6

Monitor Activated partial thromboplastin time (PTT) to assess

Answer 6

unfractionated heparin level

Question 7

Activated partial thromboplastin time (PTT) measures the function of

Answer 7

the intrinsic pathway of the coagulation cascade

Question 8

Heparin is used for

Answer 8

1. Deep vein thrombosis (DVT) prophylaxis
2. Acute treatment of deep vein thrombosis (DVT)
3. Prophylaxis and acute treatment of pulmonary embolism (PE)
4. An acute MI

Question 9

Administer IV heparin in the setting of

Answer 9

an acute DVT, PE, or MI

Question 10

Antibodies against heparin bound to platelet factor 4 cause

Answer 10

heparin induced thrombocytopenia (HIT)

Question 11

HIT results in

Answer 11

paradoxical thrombosis in the setting of thrombocytopenia

Question 12

Heparin can cause

Answer 12

1. Hypoaldosteronism
2. Osteoporosis
3. Thrombocytopenia

Question 13

Heparin induced hypoaldosteronism (Type 4 RTA) causes

Answer 13

Hyperkalemia

Question 14

Protamine sulfate reverses the anticoagulant effect of

Answer 14

unfractionated heparin (less effective for LMWH and fondaparinux)

Question 15

Protamine sulfate

Answer 15

is a positively charged molecule that binds to unfractionated heparin (negatively charged)

Question 16

low molecular weight heparin (LMWH) binds

Answer 16

antithrombin III

Question 17

The LMWH-antithrombin complex

Answer 17

the LMWH-antithrombin complex inhibits factor Xa with less of an effect on thrombin

Question 18

What effect does renal insufficiency have on LMWH

Answer 18

renal insufficiency prolongs the half-life of LMWH

Question 19

LMWH has a prolonged _______ ____

Answer 19

half life

Question 20

Heparin is ______ in pregnancy

Answer 20

safe

Question 21

Which 2 forms of Heparin are less likely to cause HIT

Answer 21

1. LMWH

2. Fondaparinux

Question 22

Fondaparinux

Answer 22

fondaparinux binds antithrombin III with higher specificity than LMWH

Question 23

The fondaparinux-antithrombin complex

Answer 23

inhibits factor Xa with less of an effect on thrombin (same as LMWH)

Question 24

Fondaparinux has the lowest risk of

Answer 24

HIT

Question 25

Direct thrombin inhibitor inhibitors

Answer 25

1. Argatroban
2. Dabigatran
3. Bivalirudin

Question 26

In HIT use

Answer 26

direct thrombin inhibitors (argatroban, dabigatran, bivalirudin)

Question 27

Direct factor Xa inhibitors

Answer 27

rivaroxaban and apixaban

Question 28

Factor Xa inhibitors

Answer 28

1. bind directly

2. are oral medications

Question 29

Direct Factor Xa inhibitors are used for

Answer 29

long term anticoagulation in atrial fibrillation