antithomrbic therapy

Question 1

unfrac heparin: what it does, how it is monitored, and who is can be used with

Answer 1

1. binds to blood components, endothelial cells, platelets, mast cells, plasma cells
2. monitored by aPTT or anti-Xa level
3. safe to use in those with kidney dz

Question 2

LMWH

distinguished from unfrac heparin

how it is monitored

who it can be used for

Answer 2

1. Enoxaparadin
2. longer half life = less administration
3. monitored with anti-Xa level
4. associated with lower frequency of HIT
5. DO NOT USE in those with kidney dz

Question 3

fondaparinux

Answer 3

1. no thrombin inhibition!
2. indirectly inhibits Xa: binds antithrombin
3. matabolized in the kidneys- do not use in kidney pts
4. once daily dosing
5. no effective neutralizing agent

Question 4

warfarin

Answer 4

1. vitamin K antagonist
2. inhibits vit K dependent carboxylase
3. requires monitoring INR

Question 5

Dabigatran etexilate: use for whom, for what, CIs

Answer 5

1. DVT or PE in pts receiving parenteral anticoagulant for 5-10 days
2. reducing risk in pts previously tx for DVT/PE
3. preventing stroke/system embolismin non vascular afib
4. prevents thrombus formation by inhibiting clotbound free thombin and thrombin induced platelet aggregation
5. dont use with strong CYP inhibitirs (rifampin)
6. neutralized by idarucizumab

Question 6

Rivaroxaban

Answer 6

1. rivaroxaban
   
   1. prevents venous thrombosis following hip or knee replacement
   2. nonvalvular afib ass stroke
   3. acute venous thrombosis
   4. recurrence of venousthromembolism
2. careful around
   
   1. amiodarone
   2. azith
   3. diltiazem
   4. drone
   5. erthro
   6. felodipine

Question 7

apixaban

Answer 7

1. approved for preventing
   
   1. stroke in nonval afib
   2. DVT following hip knee surgery
   3. prevent VTE
   4. treating acute venous thrombosis

Question 8

oral direct Xa inhibitor

Answer 8

apixaban, rivaroxaban, enoxaban

Question 10

Pt diagnosed with DVT or PE: next step

Answer 10

anticoagulate for 3 months and then reasses

Question 11

pt w/DVT/PE due to a transient risk factor: what is the next step

Answer 11

anticoagulant tx for another 3 months and reassess

Question 13

post-3 month anticoag tx for cancer pt

Answer 13

receives anticoag pt as long as the cancer is active with enoxaparin

Question 14

post-3 month anticoagulant for an unprovoked clot

Answer 14

at least 3 months of tx: consider ASA indefinitely

Question 15

underlying thrombophilia

Answer 15

indefinite anticoag tx

Question 17

low risk pt

Answer 17

1. minor procedure in age < 40 without other risk factors
2. ambulatory with expected length of stay < 24 months or surgery

Question 18

proximal DVT/PE

Answer 18

3 months anticoag tx

Question 19

high risk pt

Answer 19

1. recent major orthopedic surgeries (total hip/knee surgeries)
2. gynecologic malignancy/cancer surgery
3. spinal cord/major trauma- prolonged periods of rehabil
4. 3 or more intermediate risk factors = high risk patient

Question 20

when do we use LMWH? 4 instances

Answer 20

1. most medical pt and critical care pt
2. surgical pts: 4 wks in abdominal/pelvic cancer surgery
3. orthopedic pts:
   
   1. twice daily
      
      1. 10 day min
   2. post joint replacement
   3. up to 1 month in high risk pts
4. bariatric surgery: 2 daily

Question 21

fondaparinux

Answer 21

1. ortho pts
   
   1. 2 daily
   2. 10 day min
   3. ~1 month in high risk pts

Question 22

Didrect Oral anticoagulants: rivaroxaban

Answer 22

1. ortho pts status post op
2. total hip arthoplasty and total knee arthoplasty

Question 23

Didrect Oral anticoagulants: apixaban

Answer 23

1. ortho pts “s/p” total hip/knee replacement
   
   1. 12 days following knee surgery
   2. 35 days following hip surgery

Question 24

warfarin

Answer 24

1. few ortho pts
2. goal: INR = 2.5
3. administer for 10 days min
4. high risk pts: hip/knee replacement surgery for up to one month