Enoxaparin

Enoxaparin - is a widely used low molecular weight heparin (LMWH), similar to dalteparin. The incidence of bleeding is similar between LMWHs and unfractionated heparin.The incidence of immune-mediated thrombocytopenia is about 2–3% of patients treated with unfractionated heparin. LMWHs are preferred over unfractionated heparin because they are as effective, simplify treatment (usually once-daily dosing, no IV cannulation), have a lower risk of heparin-induced thrombocytopenia and monitoring is not required.

Uses
Peri- and post-operative surgical thomboprophylaxis
Medically acutely ill thomboprophylaxis
Treatment of DVT, pulmonary embolism or both
Unstable angina
Prevention of clotting in extracorporeal circuits

Contraindications
Generalised bleeding tendencies
Acute GI ulcer
Cerebral haemorrhage
Sub-acute endocarditis
Heparin-induced immune thrombocytopenia
Injuries to and operations on the CNS, eyes and ears
Known haemorrhagic diathesis
Hypersensitivity to enoxaparin or other LMWHs and/or heparins

Administration
Peri- and post-operative surgical prophylaxis – moderate risk
• 20 mg daily SC
   If CC _30 ml/min, 20 mg daily SC
Peri- and post-operative surgical prophylaxis – high risk
• 40 mg daily SC
   If CC _30 ml/min, 20 mg daily SC
   Treatment of DVT and pulmonary embolus or both
   Start enoxaparin with oral warfarin (as soon as possible) until INR in therapeutic range
• 1.5 mg/kg once daily SC
   If CC _30 ml/min, 1 mg/kg once daily SC
   Acute coronary syndrome:
• 1 mg/kg 12 hourly SC, recommended treatment period up to 8 days
   If CC _30 ml/min, 1 mg/kg once-daily SC
   Concomitant treatment with low-dose aspirin
   Monitor: platelets
   APTT monitoring is not usually required
   In overdose, 1 mg enoxaparin is inhibited by 1 mg protamine

Adverse effects
Subcutaneous haematoma at injection site
Bleeding at high doses, e.g., anti-Factor Xa levels greater than 1.5 iu/ml, however at recommended doses bleeding rarely occurs
Transient increase in liver enzymes (ALT) but no clinical significance has been demonstrated
Rarely thrombocytopenia
Rarely hypoaldosteronism resulting in increased plasma potassium
particularly in chronic renal failure and diabetes mellitus

How not to use enoxaparin
Not to be used for patients with heparin-induced thrombocytopenia

Renal replacement therapy
Treatment doses of low molecular weight heparins are generally avoided in RRT, since anti-Xa monitoring is required to use safely.
Thus generally, use of unfractionated heparin is preferred.However for thromboprophylactic doses it appears safe to use enoxaparin 20 mg SC once daily.