Heparin & Related Anticoagulants; L1 (9-23-15)

Question 1

Heparin

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 1

• MOA: complexes with AT(III) and inhibits factors Xa (10a) and IIa (2a; thrombin); monitored by APTT (2-2.5 = baseline therapeutic).
• ROA: mainly IV; also subcutaneous (sub-q)
• Indications: surgical anticoagulation (VENOUS THROMBOSIS–DVT* and PE; atrial fibrillation; ARTERIAL THROMBOSIS–ACS and stroke; * = til long-term therapy is in place)

-Adverse effects: **bleeding, HIT, osteoporosis, alopecia
(-Contraindications: active bleeding, bleeding disorders, hx of HIT T2, conditions worsened by anticoagulation–i.e., aortic dissection)

**OK DURING PREGNANCY. Does not cross placenta!

Question 2

LMW (low molecular weight) Heparins

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 2

• MOA: complex with AT(III) and inhibit factors Xa (10a) and IIa (2a; thrombin); monitored by anti-Xa (10a)
• ROA: sub-q
• Indications: prophylaxis and tx of DVT (+PE – VENOUS THROMBOSIS) and ACS (ARTERIAL THROMBOSIS)
• Adverse effect: **bleeding

Question 3

Fondaparinux (pentasaccharide)

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 3

• MOA: complexes with AT(III) and inhibits factor Xa (10a)
• ROA: Sub-q
• Indication: management of DVT (and PE)
• Adverse effect: bleeding

Question 4

Argatroban

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 4

• MOA: directly inhibits IIa (2a; thrombin)
• ROA: IV
• Indication: anticoagulant management of HIT patients; (preferable for pts with renal insufficiency bc it is HEPATICALLY cleared)
• Adverse effect: bleeding

Question 5

Bivalirudin

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 5

• MOA: directly inhibits IIa (2a; thrombin)
• ROA: IV
• Indication: anticoagulant management of HIT patients (alternative to heparin in PCI/angioplasty with stent + in ACS)
• Adverse effect: bleeding

Question 6

Hirudin

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 6

• MOA: directly inhibits IIa (2a; thrombin)
• ROA: IV
• Indication: anticoagulant management of HIT patients

-Adverse effect: **bleeding
(-Contraindications: active bleeding, bleeding disorders, or conditions worsened by anticoagulation–i.e., aortic dissection)

*Note: antiplatelet antibodies induced in HIT T2 do NOT react with hirudin -> safe and indicated to give hirudin to pts w/ hx of HIT T2!!

Question 7

~Antithrombin Concentrate

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 7

• MOA: directly inhibits IIa (2a; thrombin)
• ROA: IV
• Indications: DIC, sepsis, thrombophilia, hypercoagulable state
• Adverse effects: NONE

Question 8

~Protamine Sulfate

• MOA?
• Route of administration?
• Indication(s)?
• Adverse effect(s)?

Answer 8

• MOA: Heparin antagonist (basic protein that binds to and neutralizes heparin -> reverses anticoagulation)
• ROA: IV
• Indication: reversal for heparin
• Adverse effects: bradycardia, hypotension