title: A systematic review on the effect of aspirin in the prevention of post-operative arterial thrombosis in patients undergoing total hip and total knee arthroplasty.
abstract: BACKGROUND
  Major surgery is associated with increased risk of venous thromboembolism (VTE), which is decreased by anticoagulant drugs. Evidence is growing that major surgery is associated with increased risk of arterial thrombosis (AT). With the aim of testing aspirin ability in reducing the risk of post-operative AT, we performed a systematic review of studies in which acetylsalicylic acid (ASA) was compared to anticoagulant drugs in VTE prophylaxis of patients undergoing total hip replacement (THR) or total knee replacement (TKR).
  
  
  METHODS
  Studies were identified by reviewing the reference of the ACCP guidelines and by electronic search of MEDLINE database from January 2012 to December 2013 and of the web database www.trialresultscenter.org.
  
  
  RESULTS
  We analyzed 5 of the 78 studies that were identified by our search strategy; they included 5179 patients; the median follow-up was 90 days. The incidence of post-operative AT tended to be lower in ASA-treated patients, compared to anticoagulant-treated patients, although the difference did not reach statistical significance (OR 0.56, 95%CI 0.23-1.35). In contrast, the incidence of post-operative VTE tended to be higher in ASA-treated patients, compared to anticoagulant-treated patients (1.48, 95% CI 0.93-2.36).
  
  
  CONCLUSIONS
  Due to the heterogeneity and low quality of the studies, which do not allow firm conclusions, it is uncertain whether aspirin is effective in reducing the incidence of postoperative AT. Our results do emphasize the need for developing specifically designed studies to test the safety and efficacy of ASA in the prevention of post-operative AT.
authors: Haematology and Bone Marrow Transplant Unit, Azienda Ospedaliera Papa Giovanni XXIII, Bergamo, Italy; Medicina III, Azienda Ospedaliera San Paolo, Dipartimento di Scienze della Salute, Università degli Studi di Milano, Milano, Italy.
authors: Federico
authors: F
authors: Lussana
authors: Medicina 1, Ospedale di Circolo Varese, Varese, Italy.
authors: Alessandro
authors: A
authors: Squizzato
authors: Medicina 1, Ospedale di Circolo Varese, Varese, Italy.
authors: Eleonora Tamborini
authors: ET
authors: Permunian
authors: Medicina III, Azienda Ospedaliera San Paolo, Dipartimento di Scienze della Salute, Università degli Studi di Milano, Milano, Italy. Electronic address: marco.cattaneo@unimi.it.
authors: Marco
authors: M
authors: Cattaneo
mesh_terms: D000925:Anticoagulants / Q000627:therapeutic use; D001157:Arterial Occlusive Diseases / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D001241:Aspirin / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D016017:Odds Ratio; D012307:Risk Factors; D013927:Thrombosis / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome; D054556:Venous Thromboembolism / Q000209:etiology / Q000517:prevention & control
chemical_list: D000925:Anticoagulants; D005343:Fibrinolytic Agents; D001241:Aspirin
keywords: Antiplatelet agents; Arterial thrombosis; Orthopedics; Venous thrombosis