Compared to unfractionated heparin has a number of advantages including improved bioavailabilty, decreased variability in dose response curve, decreased binding to cells and plasma proteins, simplified administration and no routine anticoagulation monitoring.
Each agent possesses unique structural properties relating to its molecular weight distribution with varying biochemical, biological, antithrombotic effect and pharmacological characteristics.
These agents differ and should not be considered therapeutically equivalent to one another.
Inhibits factor Xa rather than thrombin.
Lower incidence of bleeding than with heparin.
Lower risk of heparin-induced thrombocytopenia and osteoporosis.
Low molecular weight heparin‘s are dosed based on weight, and weight changes need to be considered.
Makes treatment of venous thromboembolic disease feasible in outpatient settings.
Most common used drugs as the initial treatment of patients with VTE and cancer.
Cleared principally by the renal excretion.
Renal insufficiency a relative contraindication to LMWH therapy.
In the presence of severe renal insufficiency, in patients who require therapeutic anticoagulation, the use of unfractionated heparin is recommended over LMWH.
If utilized in patients with creatinine clearance is 30 cc/min or less it is recommended to use 50% of the usual dose.
In pregnancy it is recommended to monitor anti-Xa levels.
In obese individuals receiving LMWH weight based dosing is recommended.
No effective antidote to neutralize anticoagulant effects.
Protamine only partially effective in the neutralization of LMWHs anticoagulant process.
Reduces venous thromboembolic events during the acute phase of acute strokes when used in a prophylactic manner but at the expense of increased risk of extracranial bleeding.
Individual drugs are distinct and cannot be interchanged.
Available agents include dalteparin (Fragmin), enoxaparin (Lovenox) and tinzaparin (Innohep).
The present agents have different structural and biochemical features that affect pharmacologic profiles and are not exchangeable on a dose basis.
Once daily enoxaparin (Lovenox) may be less effective in patients with high body mass and in patients with cancer.
Unlike vitamin K antagonists it has predictable pharmacokinetic properties and drug interactions and may be useful in patients with recurrent thromboembolism while receiving warfarin.
It is less effective in patients with high body mass and in patients with cancer.
Are more effective than warfarin in patients with cancer that require long-term VTE treatment.
Is the pref2242ed agent to bridge anticoagulation for warfarin therapy by administering the last dose 24 hours prior to surgery or a procedure and for the last preoperative dose to be half the daily dose.
When utilized as a bridge anticoagulation following a minor surgical or other invasive procedure it should be resumed approximately 24 hours after the procedure when there is adequate hemostasis.
When utilized as a bridge anticoagulation following a major surgical procedure or a high risk surgery/procedure it is recommended to re-initiate treatment 48-72 hours after the procedure when hemostasis is secure.