Following the outcomes of the RECORD trials the protocol of extended thromboprophylaxis in patients undergoing elective primary total hip or knee arthroplasty has been changed in our institution.

Between June 2008 and May 2009 patients were offered extended thromboprophylaxis with 150mg of aspirin daily, commencing preoperatively on admission and continuing for a total of six weeks. From June 2009 onwards patients were treated with 10mg of rivaroxaban once daily for two weeks following total knee and five weeks following total hip arthroplasty commencing 4 to 6 hours postoperatively. Our cohorts were 700 patients before and after the introduction of the new regimen. The two groups were matched for age, sex and type of operation. All patients with no contraindication to treatment with aspirin or rivaroxaban respectively undergoing elective primary total hip or knee arthroplasty were included in the study. Patients receiving warfarin on admission were treated with warfarin postoperatively and were excluded.

We have compared the two treatment protocols in terms of safety and efficacy. Results focus on 4 safety outcome measures including mortality, haemorrhagic complications, transfusion requirements and infection rates and 2 efficacy outcome measures including thromboembolic complications and length of inpatient stay.

Rates of DVT were equal in the two cohorts (P< 0.005) as were the mortality rates. Transfusion requirements post-operatively were not affected by the introduction of the new regimen however there was a significant increase in both return to theatre rates and prolonged wound ooze (P< 0.005). Infection rates were slightly higher in the cohort treated with rivaroxaban but this was not statistically significant.

We conclude that further trials need to be done to confirm the suitability of routine use of rivaroxiban.