Evaluation of occlusive dressings for management of full-thickness excisional wounds on the distal portion of the limbs of horses.

This study explored the impact of four types of wound dressings on the healing of full-thickness skin wounds on horse limbs. The results showed that nonadherent gauze pads and equine amnion aided faster healing while synthetic fully occlusive dressings prolonged the healing duration.

Methodology

• The research simulated two 2.5-cm2 full-thickness skin wounds per limb on each of the six horses involved in the study, creating a total of 48 wounds.
• Four types of wound dressings were tested in the study. The types were a nonadherent gauze pad, a synthetic semiocclusive dressing, equine amnion, and a synthetic fully occlusive dressing. These were categorized as groups 1 to 4 respectively.
• Each wound’s progress was monitored and assessed at each dressing change.
• Total wound area, area of granulation tissue (new connective tissue and microscopic blood vessels that form on the surface of a wound during the healing process), and the area of epithelium in each wound were determined through computerized digital analysis of wound photographs.
• The complete healing time for every wound was also determined, indicating when the wound was completely covered by epithelium (skin cells).

Results

• Statistics showed that the median time to complete healing was 53 days for group 1 (nonadherent gauze pad), 71 days for group 2 (synthetic semiocclusive dressing), 63 days for group 3(equine amnion), and the longest healing period was for group 4 (synthetic fully occlusive dressing) with 113 days.
• Wounds treated with synthetic fully occlusive dressings (Group 4) took significantly longer to heal than those treated with the other solutions.
• Group-1 horses’ wounds healed more quickly compared to those of group-2.
• Wounds in group-4 horses required more extensive granulation tissue excision (average 11.5 times) compared to groups 1, 2, and 3.
• Epithelial tissue was detected later in wounds of group-4 horses than in wounds of horses in the other groups; however, this difference was not statistically significant.

Conclusions

• This research demonstrates that the type of dressing applied to a full-thickness skin wound can significantly impact the healing time in horses. Nonadherent gauze pads and equine amnion appeared to be the most effective dressings in this study.
• On the other hand, synthetic fully occlusive dressings significantly extended the healing period and required more granulation tissue excision, indicating they are potentially less beneficial for this type of wound in horses.
• These findings can provide guidance for veterinarians in the care and management of full-thickness skin wounds in horses.