Abstract
Most of current literatures advise on thromboprophylaxis with injectable LMWH for trauma patients. Injectable anticoagulants have got inherent problems of pain, bruising and difficulty in administering the drug, which leads to low compliance. Clexane is derived from a pig's intestinal mucosa, hence could be objectionable to certain proportion of patients because of their religious beliefs. Oral anticoagulants have been used as thromboprophylactic agents in hip and knee arthroplasty. However there is not enough literature supporting their use as thromboprophylactic agent in ambulatory trauma patients with ankle fracture being managed non-operatively as out-patient.
This study looks into the efficacy of oral anticoagulant in preventing VTE in ambulatory trauma patients requiring temporary lower limb immobilisation for management of ankle fracture. The end point of this study was symptomatic deep vein thrombosis (either proximal or distal) and pulmonary embolism.
Routine assessment with a VTE assessment risk proforma for all patients with temporary lower limb immobilisation following lower limb injury requiring plaster cast is done in the fracture clinic at this university hospital. These patients are categorised as low or high risk for a venous thromboembolic event depending on their risk factor and accordingly started on prophylactic dose of oral anticoagulant (Rivaroxaban - Factor Xa inhibitor). Before the therapy is started these patients have a routing blood check, which includes a full blood count and urea and electrolyte. Therapy is continued for the duration of immobilisation. Bleeding risk assessment is done using a proforma based on NICE guideline CG92. If there is any concern specialist haematologist advice is sought. A total of 200 consecutive patients who presented to the fracture clinic with ankle fracture, which was managed in plaster cast non-operatively, were included in this study. They were followed up for three months following injury. This was done by checking these patients’ radiology report including ultrasound and CT pulmonary scan (CTPA) test on hospital's electronic system. Fracture of the lateral malleolus which include Weber-A, Weber-B and Weber-C fractures were included in the study. Also included were bimalleolar fractures and isolated medial malleolus fractures. Complex pilon fractures, polytrauma and paediatric patients were excluded from the study.
Only one case of plaster associated isolated distal deep vein (soleal vein) thrombosis was reported in this patient subgroup. There was no incidence of proximal deep vein thrombosis or pulmonary embolism. No significant bleeding event was reported.
Injectable low molecular weight heparin (LMWH) rather than oral anticoagulant has been recommended by most of the studies and guidelines as main thromboprophylactic agent for lower limb trauma patients.
