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.