THROMBOPROPHYLAXIS IN PATIENTS WITH ACUTE SPINAL CORD INJURY

Abstract

Patients with acute spinal cord injury (SCI) have a high risk of venous thromboembolism (VTE) despite receiving thromboprophylaxis. The current standard of care recommended by guidelines is to use low-molecular-weight heparin (LMWH) for thromboprophylaxis for 90 days. This entails once- or twice-daily subcutaneous injections of LMWH for this duration, which is inconvenient for the patients and only partially effective. There are uncertainties about risk factors and the true incidence of SCI-associated VTE, the optimal time to commence thromboprophylaxis, and the optimal duration of thromboprophylaxis. Furthermore, there are currently no studies on the use of direct oral anticoagulants (DOACs) for thromboprophylaxis in patients with SCI. The use of DOACs for prophylaxis in this group can eliminate the inconvenience associated with daily subcutaneous injections for 3 months. To examine the incidence and risk factors of SCI-associated VTE, we performed a retrospective chart review of consecutive adult patients with acute SCI admitted to Hamilton General hospital from 2009 to 2015. The incidence of symptomatic VTE despite the use of thromboprophylaxis was 11% within 90 days of acute SCI; age and presence of other sites of injuries (such as lower limb fractures or pelvic fractures) along with SCI were independent risk factors for symptomatic VTE. To determine the opinion of Canadian spine surgeons about the optimal timing of starting LMWH after acute SCI, a short 5-question electronic survey was sent to the Canadian Spine Society. Data from our survey showed that the understanding about thromboprophylaxis after acute SCI was variable and that most spine surgeons were comfortable with starting LMWH after consultation with the surgeon. Future studies should focus on educational strategies to improve the knowledge base in this area. We will perform a pilot study at the Hamilton General Hospital comparing apixaban versus LMWH for thromboprophylaxis in patients with acute SCI. The use of apixaban for this indication can contribute to cost savings for the healthcare system and increased convenience for the patient. The protocol for the pilot study as well as steps towards a multi-center randomized controlled trial will be detailed in this thesis.