Effect of Intravenous Regional Perfusion of the Distal Limb With Amikacin Sulfate on Wounds Healing by Second Intention in Horses

OBJECTIVE: To compare the gross and histological effects of intravenous regional limb perfusion (IVRLP) using amikacin sulfate on second intention healing of distal limb wounds in adult horses with healing in untreated wounds. STUDY DESIGN: In vivo experimental study. ANIMALS: Adult horses (n = 7). METHODS: Two full thickness wounds (2.5 × 2.5 cm) were created aseptically on the dorsal aspect of each metacarpus and maintained under sterile bandages. One forelimb was randomly selected from each horse for IVRLP on days 2, 3, and 4 post‐wounding. Sequential biopsies were taken from 1 wound on each limb to evaluate the histological effects of IVRLP. Photographs were obtained of nonbiopsied wounds from days 2 to 62 for gross assessment and wound measurement. Wound size and contraction, healing rate during and immediately after IVRLP treatment, total healing rate, and histological scores for edema, hemorrhage, inflammatory infiltrate, and fibrovascular proliferation were compared. RESULTS: No differences were observed between groups for wound size, wound contraction, healing rates during or after IVRLP treatment periods, or total healing rate. Wound size over time was larger in the IVRLP group compared with the control group; however, this difference did not reach statistical significance. Mononuclear cell infiltration was greater in the IVRLP group compared with controls. No differences were observed for other histological variables. All wounds healed without the formation of exuberant granulation tissue. CONCLUSION: Treatment for 3 consecutive days with IVRLP using amikacin sulfate did not negatively affect surgical wounds healing by second intention in the distal limb of horses.