EVALUATION OF SKIN BACTERIAL-FLORA BEFORE AND AFTER ASEPTIC PREPARATION OF CLIPPED AND NONCLIPPED ARTHROCENTESIS SITES IN HORSES

Objective-This study evaluates skin bacterial flora before and after a septic preparation of clipped and nonclipped arthrocentesis sites in h orses. Study Design-The hair over one midcarpal joint and one distal i nterphalangeal joint on each horse was clipped. The contralateral join t served as the nonclipped comparison. Animals or Sample Population-Tw elve adult horses. Methods-A prescrub sample for microbial culture was taken from the dorsal surface of all four joints for each horse. Each site was aseptically prepared with povidone iodine and 70% alcohol, f ollowed by postscrub sampling for microbial culture. Colony forming un its (CFUs) were determined for each sample, 24 hours after inoculation of blood agar plates. Results-There was no significant difference (P > .05) in number of postscrub CFUs between clipped and nonclipped skin over the midcarpal or distal interphalangeal joints. Percent bacteria l reduction (mean +/- SD%) after aseptic preparation differed signific antly (P = .02) between clipped (99.8 +/- .003%) and nonclipped (96.2 +/- .05%) skin at the midcarpal joint, but not at the distal interphal angeal joint (clipped, 98.5 +/- .03% and nonclipped, 97.8 +/- 0.21%). There was a significant difference (P = .009) in number of prescrub CF Us obtained from clipped and nonclipped skin for the midcarpal joint. There was no significant difference in number of prescrub CFUs between clipped and nonclipped skin at the distal interphalangeal joint. Bact eria isolated from both clipped and nonclipped skin sampled postscrub included Bacillus sp, nonhemolytic Staphylococcus sp. and Micrococcus sp. Conclusions-The presence of hair over the midcarpal and distal int erphalangeal joints does not appear to inhibit the ability of antisept ics to effectively reduce bacterial flora to an acceptable level for a rthrocentesis. Clinical Relevance-Aseptic preparation of the skin over the midcarpal and distal interphalangeal joints can be accomplished w ithout hair removal in horses. (C) Copyright 1997 by The American Coll ege of Veterinary Surgeons.