Comparison of Butorphanol, Methadone, and Pethidine in Combination with Alfaxalone for Premedication in Isoflurane-Anesthetized Cats Undergoing Ovariectomy

Simple Summary: This study aims to assess the effects of different combinations of opioids (butorphanol, methadone, or pethidine) with alfaxalone as a premedication in cats undergoing elective ovariectomy. Data collected were analyzed to identify an anesthetic protocol that grants a stable surgical anesthetic depth, while preserving cardiorespiratory function and providing adequate analgesia in the perioperative phase. The study results showed good cardiorespiratory stability with pethidine but a low quality of sedation, which is why its use in combination with alfaxalone is not recommended in more feral feline subjects, suggesting also tailoring the choice of the opioid-based on the animal’s behavior. The combinations of the injectable anesthetic drugs assessed in this study could be a possible and advantageous choice for short and elective surgical procedures.