Antinociceptive and wound healing effects of a commercial formulation of lidocaine, bupivacaine, adrenaline and cetrimide applied topically to superficial skin wounds in horses

Vet Rec. 2024 Aug 3;195(3):e4395. doi: 10.1002/vetr.4395. Epub 2024 Jul 8.

Abstract

Background: Post-traumatic distal limb wounds cause discomfort and heal gradually by second intention. The topical application of Tri-Solfen (lidocaine hydrochloride, bupivacaine hydrochloride, adrenaline acid tartrate and cetrimide [LBAC]) produces effective postsurgical cutaneous analgesia in lambs, calves and piglets; however, its effect on wounds in horses is unknown.

Methods: The antinociceptive effect, measured by mechanical threshold (MT), and the wound healing impacts of LBAC compared with saline were investigated on surgically created 20 × 20 mm distal limb wounds in 10 horses. Treatment was applied once daily for 7 days following wounding on day 0. Mechanical thresholds were measured after treatment on days 1, 2 and 3. Healing was observed for 25 days.

Results: The topical application of LBAC immediately following wounding and its reapplication 24 hours later increased the average MT on the first post-traumatic day by 3 Newtons. However, no antinociceptive benefit was observed on days 2 or 3. Treatment with LBAC did not adversely affect wound healing when compared with saline.

Limitations: Methodological differences preclude absolute MT comparisons between studies. The experimental design did not include a model of contaminated or naturally occurring wounds.

Conclusion: LBAC may provide an early antinociceptive benefit when applied to uncontaminated surgically created wounds without compromising healing.

Keywords: Tri‐Solfen; antinociception; horse; mechanical threshold testing; wound healing.

MeSH terms

  • Administration, Topical
  • Analgesics / administration & dosage
  • Analgesics / therapeutic use
  • Anesthetics, Local / administration & dosage
  • Anesthetics, Local / pharmacology
  • Anesthetics, Local / therapeutic use
  • Animals
  • Bupivacaine* / administration & dosage
  • Cetrimonium
  • Drug Combinations
  • Epinephrine* / administration & dosage
  • Female
  • Horses
  • Lidocaine* / administration & dosage
  • Lidocaine* / pharmacology
  • Lidocaine* / therapeutic use
  • Male
  • Skin / drug effects
  • Skin / injuries
  • Treatment Outcome
  • Wound Healing* / drug effects
  • Wounds and Injuries / drug therapy
  • Wounds and Injuries / veterinary

Substances

  • Lidocaine
  • Epinephrine
  • Bupivacaine
  • Cetrimonium
  • Analgesics
  • Anesthetics, Local
  • Drug Combinations

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