Assessment of Post-Operative Bleeding and Venous Thromboembolism after Initial 24-Hour Intermittent Pneumatic Calf Compression Followed by Rivaroxaban versus Enoxaparin in Elective Hip and Knee Arthroplasty: A Multicentre Randomised Controlled Trial

Abstract

Background: Venous thromboembolism (VTE) is a serious complication following total hip replacement (THR) and total knee replacement (TKR). There are limited studies addressing the impact of mechanical intermittent pneumatic calf compression (IPCC) followed by pharmacological prophylaxis on rate of bleeding and VTE among this cohort of patients. Objectives: Our study assessed 24-hour IPCC followed by oral rivaroxaban 10 mg daily versus subcutaneous enoxaparin 40 mg daily for 14 days post-TKR and 35 days post-THR, with 6-month post-operative follow-up. Design: A multicentre open-label, randomised controlled trial (RCT) with intention to treat analysis. Setting: Primary health care. Multicenter tertiary referral centres, Tasmania and Victoria, Australia. Methods and participants: A two arm RCT recruited 750 patients referred for elective hip and knee arthroplasty to tertiary referral centres in Northern Tasmania and Victoria, Australia. All patients had IPCC (Kendall SCDTM, Covidien, MA, USA) fitted immediately post-operatively for 48-hours. Main outcomes measures: The outcomes included post-operative bleeding and occurrence of either symptomatic or asymptomatic VTE. Secondary outcomes include length of hospital stay, rate of blood transfusion and compliance to the study medications. Results: 51.8% of participants were female, average age was 66.9 (SD 11.1) years, and 54.7% had undergone TKR arthroplasty. In postoperative baseline comparisons, there were no significant differences between the two groups in blood drained (P=0.771), haemoglobin change between days 2 and 4 (P=0.473), blood transfusion rate (P=0.892) or length of hospital stay (P=0.651). At 6 months post-surgery, a total of 21 participants (2.8%) had developed VTE with 8/369 (2.1%) cases in the rivaroxaban group versus 13/371 (3.5%) in the enoxaparin group (P=0.377). Conclusions: Our study showed that at the 6-month post-operative follow-up, 24-hour IPCC followed by chemical prophylaxis was effective in VTE prophylaxis with no increased bleeding risk. These findings support employing immediate postoperative IPCC followed by pharmacological prophylaxis in arthroplasty. Further trials to confirm these findings are warranted. Clinical Trial Number: The study is registered prospectively in the Australian New Zealand Clinical Trials Registry under ACTRN12609000762257 and in the WHO International Clinical Trial Registry Platform: (http://apps.who.int/trialsearch/Trial3.aspx?trialid=ACTRN12609000762257). Funding Statement: This study was supported by the Surgery and Pathology Departments, Launceston General Hospital, Launceston, Tasmania, Australia, in affiliation with the University of Tasmania, Australia. Declaration of Interests: The authors declare no conflict of interests. Ethics Approval Statement: The study was approved by the Tasmanian Human Research Ethics Committee, Australia.