anticoagulants

Question 1

unfractionated heparin MOA

Answer 1

binds to antithrombin III

inhibition of factor II and X

small platelet inhibition

Question 2

unfractionated heparin/LMWH antidote

Answer 2

protamine

Question 3

heparin monitoring and normal ranges

Answer 3

PTT - 50-80 sec (1.5-3x baseline is therapeutic)

anti Xa - 0.3-0.7 U/mL

Question 4

adverse effects of heparin

Answer 4

bleeding

skin necrosis, HIT, altered bone metabolism

Question 5

HIT diagnosis

Answer 5

antibody tests

4 T’s score

Question 6

HIT treatment

Answer 6

argatroban

also fondaparinux and bivalrudin but not FDA approved

Question 7

LMWH MOA

Answer 7

binds w antithrombin to inhibit factor X

mild inhibition of factor II

Question 8

UFH vs LMWH

Answer 8

LMWH has more predictable response, less bleeding, no routine lab monitoring, able to be given as outpatient

Question 9

dosing adjustment for LMWH

Answer 9

renal

Question 10

bivalrudin MOA

Answer 10

direct thrombin inhibitor

Question 11

dosing adjustment for bivalrudin

Answer 11

renal

Question 12

bivalrudin dosing

Answer 12

0.1 mg/kg bolus, then 0.25 mg/kg/h

Question 13

argatroban MOA

Answer 13

direct thrombin inhibitor

Question 14

bivalrudin/argatroban monitoring

Answer 14

PTT

Question 15

argatroban dosing

Answer 15

1.7-2.0 mcg/kg/min

Question 16

good anticoagulant & DOAC for renal impairment

Answer 16

argatroban

apixaban

Question 17

argatroban dosing adjustment

Answer 17

liver dysfunction

Question 18

fondaparinux MOA

Answer 18

long acting factor X inhibitor

Question 19

fondaparinux contraindication

Answer 19

CrCl<30

Question 20

warfarin MOA

Answer 20

inhibits production of vitamin K dependent clotting factors II, VII, IX and X

converts inactive vitamin K to active vitamin K

inhibits protein C and S

Question 21

warfarin half life

Answer 21

60 hours

max impact is 5-7 days

may need to bridge w lovenox

Question 22

warfarin dosing

Answer 22

5-7.5 mg daily, then titrate to INR (2-3) q 5-7 days

Question 23

warfarin AEs

Answer 23

bleeding (higher w fluconazole, amio, bactrim, metronizadole)
skin necrosis, purple toe syndrome, vasculitis

Question 24

warfarin & factor x inhibitors antidote

Answer 24

vitamin K, kcentra

Question 25

DOACs vs warfarin

Answer 25

DOACs more predictable, more rapid onset/offset, no routine monitoring, less risk of ICH and fatal hemorrhage

DOAC more expensive

warfarin indicated for mechanical valves

Question 26

dabigatran MOA

Answer 26

direct thrombin inhibitor

Question 27

rivaroxaban, apixaban, edoxaban MOA

Answer 27

factor Xa inhibitor

Question 28

periop considerations for dabigatran

Answer 28

may need to hold dose for up to 5 days before surgery depending on CrCl

Question 29

how long to hold factor X inhibitors before surgery

Answer 29

low risk procedures -24 h

high risk procedures - 48 h

Question 30

dabigatran antidote

Answer 30

idarucizumab

Question 31

anti xa inhibitors antidote

Answer 31

andexxa