Anesthetic and analgesic effects of an opioid-free, injectable protocol in cats undergoing ovariohysterectomy: A prospective, blinded, randomized clinical trial

This study evaluated the effects of ketamine-dexmedetomidine-midazolam as part of an opioid-free, multimodal protocol in cats undergoing ovariohysterectomy. In a prospective, blinded, randomized clinical trial, cats received either 1 of 2 doses of ketamine [5 mg/kg body weight (BW), n = 10, K5 or 7 mg/kg BW, n = 13, K7] with midazolam (0.25 mg/kg BW) and dexmedetomidine (40 μg/kg BW) intramuscularly, intraperitoneal bupivacaine (2 mg/kg BW) and subcutaneous meloxicam (0.2 mg/kg BW) after surgery. Buprenorphine (0.02 mg/kg BW, intravenously) was administered if pain scores exceeded intervention scores with 2 pain scoring systems. Similar prevalence of rescue analgesia was observed (K5 = 6/10; K7 = 7/13) with significantly lower requirements in kittens (2/8) than adults (11/15). Tachypnea (K5 = 7/10 and K7 = 9/13) and desaturation (K5 = 3/10 and K7 = 4/13) were the 2 most common complications. Age influenced the prevalence of rescue analgesia. Most adult cats required opioids for postoperative pain relief.