Antithrombotic
Index
Aspirin
Heparin
Unfractionated
Low molecular weight
Warfarin
Aspirin
Heparin
Unfractionated Heparin
Must be given intravenously
INR
must be measured regularly
Prolonges APTT
Reversible
Cheaper
Low Molecular Weight Heparin (LMWH)
Can be given subcutaneously (
SC
) or intramuscularly (
IM
)
Doesn't prolong APTT
Requires longer to reverse actions
More costly
Warfarin
Action
Inhibits vitamin K dependent clotting factors (II, VII, IX and X)
Can be reversed with vitamin K over a 6 hr period
Immediate reversal with
Fresh Frozen Plasma (
FFP
)
Dosage
Therapy must be initiated with a loading dose of ~7 days
Aim for an INR range as indicated:
Condition
INR Range
Deep Vein Thrombosis (
DVT
)
Prophylaxis
2.0
DVT
Treatment
Pulmonary Embolus (
PE
) Treatment
Arterial embolism
Atrial Fibrillation (
AF
)
Transient Ischaemic Attacks (
TIA
)
2.0 - 3.0
Recurrent
DVT's
Prosthetic heart valves
3.5 - 4.5
Contraindications
