We read with interest the editorial concerning rivaroxaban for thromboemobolism prophylaxis after orthopaedic surgery [1]. We have recently completed an audit examining the use and compliance of rivaroxaban for thromboprophylaxis in patients undergoing elective hip arthroplasty. We retrospectively collected the data on 50 patients who underwent hip arthroplasty via medical notes and a telephone survey. We looked at the length of treatment with our hospital's standard agent, low molecular weight heparin (LMWH), and examined complications and patient satisfaction. Our trust then introduced a new thromboprophylactic agent, rivaroxaban and we then completed the audit cycle with a further 50 patients.
The editorial highlighted that current clinical practice is to treat patients with LMWH during their postoperative stay in hospital and discontinue the LMWH ondischarge. This was true in our trust, as we found that our patients had a mean duration of thromboprophylaxis with LMWH of 5.2 days.
Warwick [2] showed in a sample of 13,000 patients that the peak incidence of venous thromboembolism following total hip arthroplasty was 21.5 days.
Considering this evidence and the National Institute of Clinical Excellence guidelines [3], our trust replaced LMWH with rivaroxaban for thromboprophylaxis, with a guideline for patients to receive rivaroxaban 10 mg per day, continued post discharge for a total treatment time of 35 days. Our second audit found that all 50 patients had received a total of 35 days of rivaroxaban, and were therefore receiving thromboprophylaxis during the peak incidence of venous throboembolic events.
The median verbal satisfaction score for the LMWH group was 3, compared to 5 in the rivaroxaban group indicating good acceptability (A score of 1 representing most dissatisfied up and 5 as being most satisfied). Within the two groups there was no difference in the documented associated complications. One patient in the LMWH group developed a pulmonary embolus on day 23 after surgery.
In addition torivaroxaban, another oral anticoagulant, which is a direct thrombin inhibitor, has been licensed for thromboprophylaxis. The efficacy of Dabigatran (Pradaxa®,Boehringer Ingelheim, Germany) has been shown when compared to LMWH [4-5]. No studies have compared rivaroxaban with dabigatran and little evidence exists concerning the bleeding risk of these new agents.
Our audit suggests that rivaroxaban is easy to introduce into clinical practice as a thromboprophylactic agent and that it covers to the recommended extended period of risk. In addition, it is associated with high patient satisfaction rates. These newer agents should allow hospitals to improve venous thromboprophylaxis cover as a key priority within the NHS.
S. N. Phillips
B. A. Rogers
East Surrey Hospital, Redhill, UK
J. Foote
St George's Hospital, London, UK
E-mail: sioned.phillips@doctors.org.uk
References
1. Harber CR and Nathanson MH. Rivaroxaban for thromboembolism prophylaxis after orthopaedic surgery. Anaesthesia 2010; 65: 552-5.
2. Warwick D, Friedman RJ, Agnelli G, Gil-Garay E,Johnson K, FitzGerald G, et al. Insufficient duration of venous thromboembolism prophylaxis after total
replacement when compared with the time course of thromboembolic events: findings from the Global Orthopaedic Registry. Journal of Bone and Joint Surgery 2007; 89: 799-807.
3. NICE. Rivaroxaban for the prevention of venous thromboembolism after total hip or total knee replacement in adults. London: National Institute for
Clinical Excellence, 2009.
4. Eriksson BI, Dahl OE,Rosencher N et al. Dabigatran etexilateversus enoxaparin for preventionof venous thromboembolism after total hip replacement: a
randomised, double-blind, non-inferiority trial. Lancet 2007; 370:949-56.
5. Eriksson BI, Dahl OE, Rosencher N etal. Oral dabigatran etexilate vs. subcutaneous enoxaparin for the prevention of venous thromboembolism after total
knee replacement: the RE-MODEL randomized trial. Journal of thrombosis and Heamostasis 2007; 5:2178-85.
No external fundingand no competing interests declared.