title: Evaluation of arthrocentesis site bacterial flora before and after 4 methods of preparation in horses with and without evidence of skin contamination.
abstract: OBJECTIVE
  To evaluate the effectiveness of four methods of povidone-iodine preparation on skin bacterial flora of arthrocentesis sites, in horses, with and without evidence of skin contamination.
  
  
  METHODS
  Prospective randomized study.
  
  
  METHODS
  Twenty-four adult horses.
  
  
  METHODS
  Horses were assigned to either the clean or contaminated group based on housing environment and visual evidence of contamination. Using a moist sterile swab, microbial culture samples were obtained from the skin over the distal interphalangeal joints immediately before and after preparation. Each site was aseptically prepared with 1 of 4 povidone-iodine techniques: 10-minutes scrub, 5-minutes scrub, three 30-second scrubs, or commercial one-step iodophor surgical solution. Colony forming units (CFUs) were determined for each sample, 24 hours after inoculation, on blood agar plates.
  
  
  RESULTS
  Mean (+/-SD) pre-scrub CFUs/mL was significantly higher in the contaminated group (9588.33+/-1223.65) compared with the clean group (4489.00+/-3842.03) (P<.01). After preparation of the arthrocentesis sites, there were no significant differences in post-scrub CFUs/mL among the 10 minutes (mean clean, 46.00+/-64.36; mean contaminated, 28.67+/-18.04), 5 minutes (mean clean, 84.17+/-109.80; mean contaminated, 40.33+/-44.52), three 30 seconds povidone-iodine scrubs (mean clean, 95.50+/-172.29; mean contaminated, 46.67+/-56.94), or application of a commercial one-step iodophor surgical solution (mean clean, 102.17+/-161.78; mean contaminated 117.67+/-143.78); or between the clean (81.96+/-131.69) and contaminated groups (58.33+/-85.90) (P<.01).
  
  
  CONCLUSIONS
  Preparation of the distal interphalangeal joint arthrocentesis site with each of these techniques significantly reduces the bacterial flora to a similar level for arthrocentesis in horses with and without evidence of skin contamination. Clinical Relevance- Aseptic preparation of the skin over the distal interphalangeal joint may be accomplished with any of these techniques.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7060, USA.
authors.forename: Chad J
authors.initials: CJ
authors.lastname: Zubrod
authors.forename: Kelly D
authors.initials: KD
authors.lastname: Farnsworth
authors.forename: J Lindsay
authors.initials: JL
authors.lastname: Oaks
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage; D001182:Arthroscopy / Q000379:methods / Q000662:veterinary*; D006734:Horse Diseases / Q000601:surgery; D006736:Horses; D007592:Joint Diseases / Q000601:surgery / Q000662:veterinary; D011206:Povidone-Iodine / Q000008:administration & dosage; D011300:Preoperative Care / Q000379:methods / Q000662:veterinary*; D011446:Prospective Studies; D012867:Skin / Q000382:microbiology*
chemical_list: D000891:Anti-Infective Agents, Local; D011206:Povidone-Iodine