Comparison of xylazine-ketamine-guaifenesin and xylazine-tiletamine-zolazepam protocols for constant rate infusion anesthesia in horses undergoing field castration.

BACKGROUND

The common use of "triple drip" (xylazine, ketamine, and guaifenesin; XKG) is a popular protocol for constant rate infusion (CRI) in equine practice. However, due to restrictions on ketamine and guaifenesin in many countries, tiletamine-zolazepam (TZ) could serve as an alternative. To date, there have been limited studies evaluating the use of xylazine in combination with TZ (XTZ) administered via CRI to maintain surgical anesthesia in equine field practice.

AIMS/

OBJECTIVES

To compare the effectiveness and safety of XTZ infusion with the classical XKG protocol for field anesthesia.

METHODS

Twelve healthy stallions were randomly allocated to two groups (XKG and XTZ) for castration. All horses were premedicated with xylazine at 1 mg/kg intravenously (IV). The XKG group received ketamine at 2 mg/kg IV for induction, followed by maintenance with xylazine 1.375 mg/kg/h, ketamine 2.75 mg/kg/h and guaifenesin 68.75 mg/kg/h The XTZ group was induced with TZ at 1 mg/kg IV and maintained with xylazine 0.75 mg/kg/h and TZ 1.5 mg/kg/h

RESULTS

No clinically significant differences of anesthetic effects and cardiorespiratory parameters were observed between the XTZ and XKG formulation.

CONCLUSIONS

The preparation of the CRI XTZ might be effectively alternated the triple drip for maintaining anesthesia in equine field practice.