Heparin

Question 1

Which type of heparin requires monitoring of aPTT?

Answer 1

Unfractionated Heparin (UFH)

Question 2

True or False: LMWH has a more predictable anticoagulant response than UFH.

Answer 2

True

Question 3

Fill in the blank: LMWH is typically administered _______.

Answer 3

subcutaneously

Question 4

What is a common clinical use of UFH?

Answer 4

Acute coronary syndrome or during surgeries

Question 5

What is a common clinical use of LMWH?

Answer 5

Prophylaxis and treatment of deep vein thrombosis (DVT)

Question 6

Which type of heparin has a longer half-life?

Answer 6

Low Molecular Weight Heparin (LMWH)

Question 7

True or False: UFH can be reversed with protamine sulfate.

Answer 7

True

Question 8

What is the primary mechanism of action for both UFH and LMWH?

Answer 8

Inhibition of thrombin and factor Xa

Question 9

What is a key difference in the dosing of UFH versus LMWH?

Answer 9

UFH requires continuous IV infusion; LMWH is given as fixed subcutaneous doses.

Question 10

Fill in the blank: UFH is generally used in _______ settings.

Answer 10

hospital

Question 11

What is the risk associated with both UFH and LMWH?

Answer 11

Heparin-induced thrombocytopenia (HIT)

Question 12

Which type of heparin is more suitable for outpatient treatment?

Answer 12

Low Molecular Weight Heparin (LMWH)

Question 13

True or False: LMWH has a higher bioavailability than UFH.

Answer 13

True

Question 14

What is the primary route of administration for UFH?

Answer 14

Intravenous (IV)

Question 15

What is the main benefit of using LMWH over UFH?

Answer 15

Reduced need for laboratory monitoring

Question 16

Fill in the blank: The molecular weight of LMWH is _______ than that of UFH.

Answer 16

lower

Question 17

What type of patient might benefit more from UFH?

Answer 17

Patients with renal impairment

Question 18

Which type of heparin is associated with a lower incidence of HIT?

Answer 18

Low Molecular Weight Heparin (LMWH)

Question 19

True or False: LMWH can be used in pregnant patients.

Answer 19

True

Question 20

What is the primary advantage of LMWH in terms of administration?

Answer 20

It can be administered once or twice daily.

Question 21

What monitoring is required for LMWH?

Answer 21

Generally none, but anti-factor Xa levels may be checked in specific populations.

Question 22

Fill in the blank: The risk of _______ is a concern with UFH therapy.

Answer 22

bleeding

Question 23

Which type of heparin is more effective in preventing venous thromboembolism?

Answer 23

Low Molecular Weight Heparin (LMWH)

Question 24

What is the mechanism by which both UFH and LMWH prevent clot formation?

Answer 24

They enhance the activity of antithrombin III.

Question 25

QUESTIONS

Answer 25

Flashcard 1
Q: Why might you switch from LMWH to UFH infusion?
A: When rapid adjustment or reversibility is required (e.g., bleeding or surgery). Half life of UHF is 1~2 hours. And completely reversed by protamine

Flashcard 2
Q: Why is UFH preferred in renal impairment?
A: UFH is not cleared by the kidneys, while LMWH can accumulate in renal dysfunction, increasing bleeding risk.

Flashcard 3
Q: When would UFH be used for ongoing high thrombosis risk?
A: In conditions like massive PE, extensive DVT, or acute coronary syndrome requiring tight monitoring and quick adjustments in aptt.

Flashcard 4
Q: Why is UFH preferred in suspected heparin-induced thrombocytopenia (HIT)?
A: UFH allows for frequent platelet monitoring and rapid cessation if needed. But LMWH is less likely to cause Hitt.

Flashcard 5
Q: When is UFH used if LMWH fails?
A: If there’s progression of thrombosis despite LMWH, UFH offers more controlled anticoagulation to achieve the targetted aptt

Question 26

if lmwh has been given as tx dose, why would someone require infusion

Answer 26

, low-molecular-weight heparin (LMWH) is sufficient for anticoagulation. However, there are specific scenarios where transitioning to unfractionated heparin (UFH) infusion might be necessary even if LMWH has already been started. These include:

1. Need for Rapid Adjustment or Reversibility:
   • UFH has a short half-life (~1-2 hours) compared to LMWH (~12 hours), and its effects can be completely reversed with protamine sulfate. This is critical in situations like:
   • Active bleeding or high bleeding risk.
   • Emergent surgery or invasive procedures.
2. Renal Impairment:
   • LMWH is primarily cleared by the kidneys, so in severe renal dysfunction (e.g., CrCl < 30 mL/min), there is a risk of drug accumulation and bleeding. In such cases, UFH infusion is preferred because it is not dependent on renal clearance.
3. Ongoing High Risk of Thrombosis:
   • If a patient’s clinical status changes and requires continuous anticoagulation monitoring, UFH infusion allows for precise dose adjustments based on aPTT or anti-Xa levels. This is important in:
   • Massive pulmonary embolism (PE) needing thrombolysis.
   • Extensive DVT with risk of propagation.
   • Acute coronary syndromes needing PCI.
4. Heparin-Induced Thrombocytopenia (HIT) Monitoring:
   • If there is a concern for HIT, UFH is often preferred as it requires frequent platelet monitoring and can be easily stopped.
5. Failure of LMWH:
   • If there is progression of thrombosis despite LMWH therapy, UFH infusion may be initiated to achieve tighter control of anticoagulation.
6. Pregnancy or Peripartum Period:
   • In some pregnant patients, especially near delivery, UFH may be preferred due to its shorter half-life and reversibility compared to LMWH.

Example Scenario:

A patient receiving LMWH for DVT suddenly needs an urgent surgical intervention. LMWH cannot be fully reversed, so the patient is switched to UFH infusion for better control and the option of rapid reversal.