Elective hip and knee arthroplasty and the effect of rivaroxaban and enoxaparin thromboprophylaxis on wound healing.

INTRODUCTION: Rivaroxaban is the first licensed oral direct inhibitor of factor Xa. Recent studies from the RECORD trials suggest rivaroxaban has superior efficacy compared to enoxaparin in preventing venous thromboembolism (VTE) with no significant increase in the major bleeding risk. Concerns remain regarding the incidence of minor bleeding, consequent delayed wound healing and subsequent risk of infection. The aim of this observational study was to assess the incidence of post-operative complications in patients receiving either rivaroxaban or enoxaparin thromboprophylaxis following elective hip and knee arthroplasty. METHODS: A total of 258 patients undergoing elective total hip or knee arthroplasty within one NHS Trust were included. A total of 202 subjects (mean age, 70.7 years ± 10.0, 43 % men) received a daily dose of 10 mg of oral rivaroxaban and 56 (mean age, 70.9 years ± 9.8, 39 % men) had a daily subcutaneous injection of 40 mg of enoxaparin as thromboprophylaxis. Endpoints included VTE (deep vein thrombosis and pulmonary embolism), haemorrhagic wound complications, hospital re-admission, requirement for blood transfusion, minor and major bleeding and death. RESULTS: There were no significant differences in the incidence of VTE, requirement for blood transfusion and readmission rate between rivaroxaban and enoxaparin-treated patients. The incidence of minor bleeding (2.0 vs. 0 %) and haemorrhagic wound complications (5.0 vs. 1.8 %) were non-significantly higher in the rivaroxaban-treated group. There were no cases of pulmonary embolism, major bleeding or death in either group. CONCLUSION: Our experience with rivaroxaban in elective hip and knee arthroplasty showed no significant difference in the incidence of VTE or major bleeding. There was, however, a tendency to greater risk of minor bleeding and wound complications that were largely haemorrhagic in nature, which may have reached significance in a larger study.

The effect of the grade of surgeon on blood loss in fractured neck-of-femur surgery.

Significant blood loss in neck-of-femur (NOF) fracture surgery contributes to the high morbidity and mortality. Since the introduction of the European Working Time Directive, trainee surgeons are more junior and inexperienced. We assessed NOF surgical blood loss in relation to the surgeon grade and experience. We assessed a prospective consecutive cohort of 105 acute NOF fracture patients treated surgically. Blood loss was calculated as the difference between the pre- and post-operative haemoglobin levels. Warfarin was reversed pre-operatively where necessary. There were 32 male and 73 female patients, with mean age 83.8 years (range 48-98). One patient died peri-operatively and was excluded. There were 49 intra-capsular fractures and 55 extra-capsular fractures, with no significant difference in group characteristics. Mean haemoglobin drop was 2.8 g/dL [intra-capsular fractures, 2.5 g/dL; extra-capsular fractures, 3.1 g/dL (p = 0.019)]. The difference in blood loss between different surgeon grades was not significant: consultants 2.4 g/dL (21 cases), senior staff grades 2.7 g/dL (17 cases), junior staff grades 3.1 g/dL (15 cases) and registrars 2.9 g/dL (50 cases). Whilst mean haemoglobin drop was least for consultants, the mean for trainees was only marginally higher than for experienced staff grade surgeons and lower than for their junior counterparts. Mean blood loss for patients taking anti-platelet agents was not significantly different (aspirin 2.7 g/dL, clopidogrel 3.7 g/dL, 4.4 g/dL for those taking both) compared to patients taking neither agent (2.8 g/dL). We conclude that surgeon grade does not significantly impact peri-operative haemoglobin drop, regardless of pre-operative morbidity. It is safe for trainees to operate, with adequate supervision where appropriate, on all NOF fracture patients without compromising blood loss.