Abstract
Background: Aetiology of venous thromboembolism is multifactorial and thromboprophylaxis includes mechanical and chemical agents. There is no clear consensus on the choice of chemical agent in elective total hip arthroplasty (THA), although National Institute of Clinical Excellence (NICE) recommends low molecular weight heparin or fondaparinux to all patients.
Aim: The aim of our study was to define the efficacy and safety of various chemical agents currently used for venous throboprophylaxis – namely aspirin, warfarin and low molecular weight heparin in primary THA.
Methods: We retrospectively reviewed 905 consecutive patients with primary THA during an 18 month period. Medical notes were reviewed to record demographic data, inpatient and outpatient thromboprophylactic agents, total hospital stay, readmission, incidence of DVT, pulmonary embolism and death following surgery. Post-operative mobility, transfusion requirements and complications were noted. Suspected thromboembolic events were investigated with venous Doppler ultrasound scanning and CTPA.
Results: 417 (46%) patients received aspirin, 253 received enoxaparin, 190 patients had low dose warfarin and 45 patients had none or multiple agents for inpatient thromboprophylaxis. 615 patients had cemented and 290 patients received uncemented total hip arthroplasty. Patients predominantly received aspirin (61%) as outpatient prophylactic agent. 41 patients were investigated for a suspected thromboembolic event. 2 patients had DVT and 2 patients had PE. There were 3 deaths within 6 weeks, one each due to PE, sepsis and unknown cause. All 4 patients with thromboembolism were on enoxaparin for prophylaxis.
Conclusion: In our study aspirin was the preferred choice for thromboprophylaxis following total hip arthroplasty. We found that aspirin was most effective with no complications and enoxaparin was least effective. We advise the use of aspirin as the first choice drug for thromboprophylaxis as reiterated by some recent studies.
The abstracts were prepared by Mr Matt Costa and Mr Ben Ollivere. Correspondence should be addressed to Mr Costa at Clinical Sciences Research Institute, University of Warwick, Clifford Bridge Road, Coventry CV2 2DX, UK.
