Heparin

Question 1

What is the mechanism of action of heparin?

Answer 1

• potentiates and enhances the activity of antithrombin III and inactivates thrombin and other clotting factors

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 3
UpToDate - Heparin: Drug Information}

Question 2

Anticoagulation with heparin depends on the presence of adequate amounts of circulating ____________

Answer 2

• antithrombin III

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 3
UpToDate - Heparin: Drug Information}

Question 3

Standard cardiac surgery dosing of heparin = ___________

Heparin dosing for active VTE/PE/MI = __________

Answer 3

• 300-400 units/kg, redosed/titrated based on ACT
• 5,000 units IV bolus followed by infusion titrated to target aPTT

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 3
Apex Unit 9: Fluids & Blood; Cogaulation; Lesson 12. Heparin
UpToDate - Heparin: Drug Information}

Question 4

What is the onset of action for heparin (IV)?

Answer 4

• Immediate

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 3
UpToDate - Heparin: Drug Information}

Question 5

What is the duration of action for heparin (IV)?

Answer 5

• ~1-2 hours

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 3
UpToDate - Heparin: Drug Information}

Question 6

Rapid IV bolus of heparin may cause ________

Answer 6

• transient vasodilation/hypotension

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 3
UpToDate - Heparin: Drug Information}