We evaluated the safety and efficacy of total knee replacement in patients receiving continuous warfarin therapy.

We identified 24 consecutive patients receiving long-term warfarin therapy who underwent total knee replacement between 2006 and 2008 and compared them with a group of age- and gender-matched patients not on long-term anticoagulation. Primary observations were changes in haemoglobin, transfusion rates and complications. Secondary observations were fluctuations in the international normalised ratio (INR) and post-operative range of movement.

There was no significant difference between the two groups in pre- or post-operative haemoglobin, incidence of transfusion or incidence of post-operative complications. There were no surgical delays due to a high INR level. The mean change in INR during the peri-operative phase was minimal (mean 0.4; sd 0.7). There was no significant difference in the range of movement between the two groups after day two post-operatively.

Current American College of Chest Physicians guidelines recommend bridging therapy for high-risk patients receiving oral anticoagulation and undergoing major orthopaedic procedures. We have shown that a safe alternative is to continue the steady-state warfarin peri-operatively in patients on long-term anticoagulation requiring total knee replacement.

In order to compare the effect of oral apixaban (a factor Xa inhibitor) with subcutaneous enoxaparin on major venous thromboembolism and major and non-major clinically relevant bleeding after total knee and hip replacement, we conducted a pooled analysis of two previously reported double-blind randomised studies involving 8464 patients. One group received apixaban 2.5 mg twice daily (plus placebo injection) starting 12 to 24 hours after operation, and the other received enoxaparin subcutaneously once daily (and placebo tablets) starting 12 hours (± 3) pre-operatively. Each regimen was continued for 12 days (± 2) after knee and 35 days (± 3) after hip arthroplasty. All outcomes were centrally adjudicated. Major venous thromboembolism occurred in 23 of 3394 (0.7%) evaluable apixaban patients and in 51 of 3394 (1.5%) evaluable enoxaparin patients (risk difference, apixaban minus enoxaparin, -0.8% (95% confidence interval (CI) -1.2 to -0.3); two-sided p = 0.001 for superiority). Major bleeding occurred in 31 of 4174 (0.7%) apixaban patients and 32 of 4167 (0.8%) enoxaparin patients (risk difference -0.02% (95% CI -0.4 to 0.4)). Combined major and clinically relevant non-major bleeding occurred in 182 (4.4%) apixaban patients and 206 (4.9%) enoxaparin patients (risk difference -0.6% (95% CI -1.5 to 0.3)).

Apixaban 2.5 mg twice daily is more effective than enoxaparin 40 mg once daily without increased bleeding.

The risk of venous thromboembolism in patients following arthroplasty may be reduced by continuing chemical thromboprophylaxis for up to 35 days post-operatively. This prospective cohort study investigated the compliance of 40 consecutive consenting patients undergoing lower limb arthroplasty with self-administration of a recommended subcutaneous chemotherapeutic agent for six weeks after surgery. Compliance was assessed by examination of the patient for signs of injection, number of syringes used, and a self-report diary at the end of the six-week period. A total of 40 patients, 15 men and 25 women, were recruited. One woman was excluded because immediate post-operative complications prevented her participation. Self-administration was considered feasible in 87% of patients (95% confidence interval (CI) 76 to 98) at the time of discharge. Among this group of 34 patients, 29 (85%) were compliant (95% CI 73 to 97). Patients can learn to self-administer subcutaneous injections of thromboprophylaxis, and compliance with extended prophylaxis to six weeks is good.

A once-daily dose of rivaroxaban 10 mg, an oral, direct Factor Xa inhibitor, was compared with enoxaparin 40 mg subcutaneously once daily for prevention of venous thromboembolism in three studies of patients undergoing elective hip and knee replacement (RECORD programme).

A pooled analysis of data from these studies (n = 9581) showed that rivaroxaban was more effective than enoxaparin in reducing the incidence of the composite of symptomatic venous thromboembolism and all-cause mortality at two weeks (0.4% vs 0.8%, respectively, odds ratio 0.44; 95% confidence interval 0.23 to 0.79; p = 0.005), and at the end of the planned medication period (0.5% vs 1.3%, respectively; odds ratio 0.38; 95% confidence interval 0.22 to 0.62; p < 0.001). The rate of major bleeding was similar at two weeks (0.2% for both) and at the end of the planned medication period (0.3% vs 0.2%).

Rivaroxaban started six to eight hours after surgery was more effective than enoxaparin started the previous evening in preventing symptomatic venous thromboembolism and all-cause mortality, without increasing major bleeding.

Several aspects of the management of an orthopaedic surgical patient are not directly related to the surgical technique but are nevertheless essential for a successful outcome. Blood management is one of these. This paper considers the various strategies available for the management of blood loss in patients undergoing orthopaedic and trauma surgery.