Aspirin monotherapy is a suitable standard thromboprophylactic agent following total hip arthroplasty

Aspirin is increasingly recognised as an efficacious thromboprophylactic agent with a superior safety profile compared to alternatives. Following our institution's previously published experience we implemented a risk-stratified protocol utilising aspirin as standard. We now present retrospective review of standard use of aspirin on fatal pulmonary embolism, all-cause mortality, and venous thromboembolism (VTE) following total hip arthroplasty (THA).

A consecutive series of elective THAs was identified. Prospectively maintained databases were analysed to yield demographic data and identify deaths or readmission data. Patients who died within 90 postoperative days underwent review of the complete medical record.

4204 THAs were included in the study cohort. VTE prophylaxis prescription was available in 3805. 2560 received aspirin (67.3%), 1049 enoxaparin (27.6%) and 193 warfarin (5.1%); there were no differences in 90-day all-cause mortality (p = 0.780) or VTE (p = 1) between groups.

Our large series continues to demonstrate that aspirin for thromboprophylaxis following THA is effective in risk-stratified patients. Furthermore, we demonstrate that introduction of a departmental protocol establishing aspirin as standard practice was not associated with increased mortality or incidence of thromboembolism. Taken in conjunction with our previous cohort our series encompasses 11,420 consecutive THAs. There has been a single death following fatal PE in the aspirin group (0.02%) compared to 5 in the LMWH group (0.2%) and 1 in the warfarin group (0.06%). We join calls for large-scale randomised controlled trials to elucidate the place of aspirin in VTE prevention following hip arthroplasty.