NEWS NOTES

Ethanol Useful for Aseptic Distal Limb Prep

Ethanol can be used to prepare the skin before performing immediate, short procedures in horses, according to a recent study.

This randomized trial aimed to determine whether ethanol-based antisepsis reduces bacterial counts on the equine distal limb comparable to a current chlorhexidine scrub method and determine the most effective application technique for the product.

They studied 41 horses, and each horse had a 5 x 5 cm patch clipped over the distal interphalangeal joint of 3 limbs. By horse, each limb was randomly assigned to a treatment group:

1. 5-minute scrub using 4% chlorhexidine gluconate to a clipped site (CHG);

2. 90-second scrub using 80% ethanol to a clipped site (ETC);

3. 90-second contact with 80% ethanol applied as a spray to a clipped site (ETS); and

4. 90-second scrub using 80% ethanol to an unclipped site (ETUC).

Samples were collected pre- and post-treatment and plated in duplicate. Bacterial counts were log10 transformed and averaged between duplicates. Mean log10 colony forming units (CFU) reduction was compared among the groups. There was no significant difference in mean log10 CFU reduction between CHG and ETC in either fore- or hindlimbs. In forelimbs, there was no significant difference in mean log10 CFU reduction among any groups. In hindlimbs, CHG had significantly greater mean log10 CFU reduction than ETUC and ETS.

A 90-second wet contact time using gauze sponges was recommended. In addition, the researchers noted that the study did not investigate the efficacy of other alcohol-based antiseptics such as isopropanol or n-propanol. MeV

For more information:

Doyle AJ, Saab ME, Lewis KM, et al. Comparison of chlorhexidine and alcohol-based antisepsis of the distal limbs of horses. Equine Vet J. 2020 Dec. 31 https://doi.org/10.1111/evj.13417 https://beva.onlinelibrary.wiley.com/doi/10.1111/evj.13417