Patient compliance with venous thromboembolism prophylaxis (VTE)

Venous thromboembolic disease (VTE) comprises pulmonary embolism (PE) and deep vein thrombosis (DVT), and causes morbidity and mortality, particularly in trauma and orthopaedic patients. Prevalence of 0.9% and 1.2% respectively are reported, with mortality rates up to 13.8%. Chemical thromboprophylactic agents including low molecular weight heparin (LMWH) are considered cost effective in reducing VTE risk. Evidence for anti-platelets including Aspirin for VTE prophylaxis is less compelling and is not supported as monotherapy. There has been no published data on patient compliance with LMWH in trauma outpatients. We aimed to determine whether trauma outpatients accept LMWH after discussing their VTE risk and the evidence for prophylaxis. For those accepting prophylaxis, we also investigated their compliance for the duration of immobilisation. Lower limb injured patients treated with external immobilisation over a 6 month period at our major trauma centre were included. On completion of immobilisation, they were requested to complete a 17-point questionnaire. Patients declining injectable subcutaneous LMWH as prophylaxis were offered Aspirin 75 mg as a second line agent. Seventy-five questionnaires were completed and five were excluded. Nineteen patients required surgical intervention for their injury, 51 were managed non-operatively. Thirty-one patients accepted LMWH and 30 chose Aspirin as an alternative. Nine patients declined or were not commenced on prophylaxis. Nineteen reported no missed Aspirin doses and 25 reported no missed LMWH doses. No patients reported missed doses due to pain, side effects or cessation of treatment for another reason. The mean average pain score recorded on the VAS was 3.8. No patients in the study were diagnosed with a VTE. LMWH is a recognised chemical thromboprophylactic and is well tolerated by patients for VTE risk reduction in lower limb immobilised outpatients. With poor evidence supporting Aspirin as a solo prophylactic agent, our local policy has withdrawn Aspirin for this purpose.