Cross-sectional survey of anaesthesia and analgesia protocols used to perform routine canine and feline ovariohysterectomies

Objective To collect baseline descriptive data on the anaesthesia and analgesia protocols used by New Zealand veterinarians in first-opinion practice when performing routine canine and feline ovariohysterectomies. Study design Cross-sectional survey. Animals Not applicable. Methods An online survey was conducted asking respondents for: 1) preoperative patient assessment; 2) preanaesthetic medication and induction drugs used; 3) anaesthesia maintenance drug choices and monitoring equipment used; and 4) postoperative analgesia drug selections and monitoring for ovariohysterectomy performed in healthy adult dogs and cats. Results The survey was completed by 472 veterinarians, of whom 282 provided responses for canine ovariohysterectomy and 361 provided responses for feline ovariohysterectomy. Approximately 23% of canine ovariohysterectomies and 13% of feline ovariohysterectomies had preanaesthetic bloodwork performed. There were 74 unique premedication/induction drug combinations reported for canine ovariohysterectomies and 94 for feline ovariohysterectomies. The most commonly used drug combinations were acepromazine, morphine +/- propofol and butorphanol, ketamine and medetomidine for canine and feline ovariohysterectomies respectively. Most animals were intubated, and anaesthesia was maintained with isoflurane in oxygen. Use of intravenous catheters, fluid administration, heat support, and monitoring equipment varied. There were 41 unique postoperative analgesia drug combinations reported for canine ovariohysterectomies and 20 for feline ovariohysterectomies. Canine ovariohysterectomies were most commonly administered injectable opioids on the day of surgery followed by 3 days of oral non-steroidal anti-inflammatory drugs (NSAIDs), whereas feline ovariohysterectomies were usually administered a single injection of an opioid or NSAID or both on the day of surgery. Most animals were seen within 7-10 days for reexamination and/or suture removal. Conclusions and clinical relevance Veterinarians use a wide range of anaesthesia and analgesia protocols for routine ovariohysterectomies. Further research is needed comparing the safety and efficacy of commonly used protocols to determine whether there are opportunities to improve the level of patient welfare.