title: Safety and efficacy of warfarin in paediatric patients with prosthetic cardiac valves: a retrospective audit.
abstract: BACKGROUND
  Guidelines for warfarin management in children are essentially extrapolated from adult evidence. This study aimed to address that lack of paediatric-specific data regarding warfarin safety and efficacy for this population.
  
  
  METHODS
  A retrospective clinical audit was conducted within a cardiac referral centre incorporating a paediatric anticoagulation service. Children (0-16 years) with a prosthetic cardiac valve were included. Warfarin related outcomes were collected between January 1st 2004 and December 31st 2009. Analysis included the percentage of INR tests within, above, or below the target therapeutic range (TTR). Adverse event data was collected regarding major bleeding and thrombotic events.
  
  
  RESULTS
  75 patient years of warfarin therapy were recorded. 44.0% of INR tests were within the TTR. INR tests not within the TTR were twice as likely to be sub-therapeutic. Children with aortic prosthetic valves achieved their TTR less frequently than children with prosthetic mitral or tricuspid valves. There were no thrombotic events and 3 major bleeding events.
  
  
  CONCLUSIONS
  Although less than 50% of INR results were within the TTR, oral anticoagulant management resulted in acceptable safety and efficacy outcomes for this cohort. Further studies are needed to confirm optimal paediatric-specific warfarin management strategies for children with prosthetic heart valves.
authors.affiliation: Department of Nursing, The University of Melbourne.
authors.forename: Centison S
authors.initials: CS
authors.lastname: Wong
authors.forename: Kate
authors.initials: K
authors.lastname: Batchelor
authors.forename: Jim
authors.initials: J
authors.lastname: Bua
authors.forename: Fiona
authors.initials: F
authors.lastname: Newall
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000704:Analysis of Variance; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001777:Blood Coagulation / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D016903:Drug Monitoring / Q000379:methods; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation*; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019934:International Normalized Ratio; D008297:Male; D008485:Medical Audit; D012189:Retrospective Studies; D013923:Thromboembolism / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors; D016896:Treatment Outcome; D014739:Victoria; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D014859:Warfarin