Enoxaparin (Orthopaedic VTE Prophylaxis)

How it works

It binds antithrombin to accelerate inhibition of factor Xa (and, to a lesser extent, thrombin), reducing clot formation in the high-risk post-operative period.

Prescribing in practice

• Account for bleeding risk and the timing relative to neuraxial (spinal/epidural) anaesthesia, as the SPC specifies intervals to reduce the risk of spinal haematoma.
• Dose requires reduction and increased caution in significant renal impairment because of accumulation; avoid in active major bleeding.
• Monitor for heparin-induced thrombocytopenia and avoid in those with a history of immune HIT.

Monitoring

Monitor platelet count, renal function and haemoglobin, with anti-Xa levels reserved for selected patients such as those with renal impairment or extremes of weight.

Counselling the patient

• Injections are given just under the skin of the abdomen; rotate sites.
• Report unusual bruising, bleeding that will not stop, or blood in urine or stool.
• Continue for the full prescribed prophylaxis duration after your operation.

Evidence & guidelines

NICE NG89 recommends extended pharmacological VTE prophylaxis after major orthopaedic surgery, with LMWH a standard option.