Patient safety alert from NHS England: low molecular weight heparins

NHS England has issued a patient safety alert following more than 70 incidents where low molecular weight heparin (LMWH) was given to patients despite known contraindications, 16 of which resulted in severe harm or death.

For ambulance staff, the alert is for information only, in case you come across a patient who may be have taken LMWH despite a contraindication.

The drug is frequently used for treatment and for prophylaxis of a variety of thromboembolic conditions. Circumstances where LMWH may be contraindicated include: active bleeding; acquired bleeding disorder (such as acute liver failure); concurrent use of anticoagulants known to increase risk of bleeding; concurrent use of antiplatelets and other interacting medicines; or, lumbar puncture/epidural/spinal anaesthesia within the previous four hours, or expected within the next 12 hours.

An example of one of the incidents reported to NHS England reads:

‘Patient admitted on warfarin, co-prescribed enoxaparin, INR 3.6 on admission but not checked regularly thereafter, and on clarithromycin. Patient became unwell, (INR 10) bilateral subdurals found five days later. Entered a phase of prolonged seizures and subsequently died.’

The full patient safety alert is available to download from the Need to Know site.