title: A prospective study of the safety of joint and soft tissue aspirations and injections in patients taking warfarin sodium.
abstract: OBJECTIVE
  To determine the safety of joint or soft tissue aspirations and injections in patients taking warfarin sodium.
  
  
  METHODS
  The outcome of 32 joint or soft tissue aspirations or injections in patients receiving stable doses of warfarin sodium was assessed through a standardized interview 4 weeks after the procedure. The primary outcome measure was significant joint or soft tissue hemorrhage, ascertained by patient-reported increases in swelling or warmth at the procedure site.
  
  
  RESULTS
  None of 32 procedures was complicated by joint or soft tissue hemorrhage reported by the patients, yielding, by the "rule of threes," a risk of significant hemorrhage of < 10% (with 95% certainty). Diagnostic information was obtained for 53% of aspirated sites (8 of 15) and therapeutic benefit was noted in 74% of corticosteroid-injected sites (17 of 23).
  
  
  CONCLUSIONS
  Joint or soft tissue injections and aspirations in selected patients taking warfarin sodium are associated with a low risk of hemorrhage and are often of diagnostic or therapeutic value.
authors.affiliation: Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: J
authors.initials: J
authors.lastname: Thumboo
authors.forename: J D
authors.initials: JD
authors.lastname: O'Duffy
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use*; D001168:Arthritis / Q000209:etiology; D002062:Bursitis / Q000209:etiology; D003238:Connective Tissue / Q000473:pathology; D005069:Evaluation Studies as Topic; D005260:Female; D006395:Hemarthrosis / Q000209:etiology; D006470:Hemorrhage / Q000188:drug therapy / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D007267:Injections / Q000009:adverse effects / Q000379:methods / Q000592:standards*; D019934:International Normalized Ratio / Q000592:standards; D007596:Joints / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009339:Needles; D010146:Pain / Q000209:etiology; D011446:Prospective Studies; D012647:Self-Assessment; D013396:Suction / Q000009:adverse effects / Q000379:methods / Q000592:standards*; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D014859:Warfarin