819 Assessing Regional Variation in VTE Prophylaxis Prescribing Practice Following Major Lower Limb Arthroplasty

Aim There is uncertainty regarding optimal post-operative pharmacological VTE prophylaxis regime following total hip and knee arthroplasty (THA/TKA). 2023 International Consensus Meeting on Venous Thromboembolism (ICM-VTE) guidelines recommend low-dose aspirin for 14 to 35 days in TKA and THA patients. Variation in practice may increase prescribing errors and healthcare-associated costs. Method This study defines current VTE prophylaxis regimes following primary THA and TKA in a UK-based region. A cross-sectional survey was performed. Training registrars affiliated with the OSCAR collaborative group documented the standard pharmacological VTE prophylaxis regime of named consultant arthroplasty surgeons in four units within the Oswestry-Stoke rotation. Results The practice of 29 consultants performing primary THA were documented. 10 different regimes were noted considering agent type and duration. 8 (27.6%) preferred low-molecular-weight heparin (LMWH), 1 (3.4%) aspirin and 4 (13.8%) direct oral anticoagulant (DOAC) alone. 10 (34.5%) used LMWH followed by aspirin or DOAC. 6 (20.7%) used LMWH alone or LMWH followed by aspirin depending on thrombotic risk. 9 different regimes for 30 consultants performing primary TKA were identified. LMWH, aspirin and DOAC alone were preferred by 10 (33.3%), 1 (3.3%) and 4 (13.3%) consultants respectively. 8 (26.7%) used LMWH as in inpatient followed aspirin or DOAC on discharge. 6 (20.0%) used either LMWH or aspirin alone depending on high- or low-thrombotic risk respectively. Conclusions Even within a limited geographical region significant variation in pharmacological VTE prophylaxis prescribing exists. A randomised-controlled trial to compare efficacy of agents is required, though challenging due to the numbers required to adequately power this study.