The necessity of pharmacological prophylaxis against venous thromboembolism in major joint arthroplasty

Abstract

Venous thromboembolism (VTE) is a recognised post-operative complication of major lower limb joint arthroplasty. Current National Institute for Health and Clinical Excellence (NICE) guidelines suggest the use of both mechanical and pharmacological prophylaxis following hip and knee replacement. Since the introduction of enhanced recovery programmes following hip and knee arthroplasty the requirement for routine pharmacological VTE prophylaxis has been questioned. The purpose of this study was to assess the efficacy of pharmacological prophylaxis against symptomatic VTE in patients undergoing hip and knee arthroplasty under an enhanced recovery programme. Symptomatic VTE incidence was audited in 1,100 patients undergoing primary or revision total hip or knee arthroplasty at the same hospital with only mechanical prophylaxis from 2007 to 2009. Following addition of chemical prophylaxis (enoxaparin) symptomatic VTE incidence in 522 patients undergoing primary or revision total hip or knee arthroplasty from 2011 to 2012 was re-audited. In the mechanical prophylaxis group incidence of DVT was 0.73 % [95 % confidence interval (CI) 0.37-1.43 %] and incidence of pulmonary embolism (PE) 0.91 % (95 % CI 0.49-1.67 %). Following addition of pharmacological prophylaxis incidence of DVT was 0.57 % (95 % CI 0.20-1.68 %) and incidence of PE 1.15 % (95 % CI 0.53-2.48 %). We found no statistically significant difference in symptomatic VTE incidence following the addition of enoxaparin. We question whether routine pharmacological prophylaxis still has a role following total hip and knee arthroplasty. Peri-operative optimisation, including post-operative analgesia and mobility, with current enhanced recovery programmes may be sufficient. As anticoagulants carry increased risk of post-operative bleeding and wound ooze, in addition to significant cost implications, their role remains controversial.