A comparison of complications requiring return to theatre in hip and knee arthroplasty patients taking enoxaparin versus rivaroxaban for thromboprophylaxis.

BACKGROUND There is no consensus on the optimal form of venous thromboembolic prophylaxis treatment in hip and knee arthroplasty patients, or on the safety and complication profile of the available chemical prophylaxis modalities. In this study we aimed to measure the return to theatre rate for any cause related to wound complications in patients undergoing total hip replacement and total knee replacement, and compare these rates between patients on oral Rivaroxaban 10mg OD and subcutaneous Enoxaparin 40mg OD in our department. MATERIAL AND METHODS There were a total of 387 patients included in the study; 227 patients in group 1, who received Enoxaparin 40mg OD, and 160 patients in group 2, who received Rivaroxaban 10mg OD. RESULTS The primary outcome measure was re-operation rate due to wound complications. Secondary outcome measures were infection rate, incidence of deep vein thrombosis, pulmonary emboli, duration of hospital stay, change in haemoglobin and haematocrit and blood transfusion rate. In this retrospective cohort study we found that patients who received Rivaroxaban were more than twice as likely to return to theatre for wound complications compared to patients receiving Enoxaparin. Although not statistically significant, this increase is in line with previous studies. Infection rates increased from 0.9% to 1.9% after the introduction of Rivaroxaban and microbiologically confirmed superficial infections rose from 1.3% to 3.1% after Rivaroxaban was introduced in our unit. These rises were not statistically significant. CONCLUSION Our study highlights the need for large randomised controlled trials to assess post-operative complications following the introduction of Rivaroxaban for post-arthroplasty thromboprophylaxis.