How painful are cats after neutering - a field study using multimodal analgesia with intraperitoneal ropivacaine in a -neuter-return program in feral cats.

For a large-scale trap-neuter-return program 119 cats were anaesthetised with an intramuscular combination of 0,03-0,05 mg/kg medetomidine, 7-10 mg/kg ketamine and 0,4 mg/kg butorphanol. Cats received intraoperative 4 mg/kg tolfenamic acid subcutaneously and before closure of abdominal wall either 2 mg/kg ropivacaine (ROPI) intraperitoneal or saline (NaCl) in equal volumes. Pain was scored one, six and 20 hours postoperative with the modified Glasgow Composite Pain Scale (mGCPS) and the modified Colorado State University Scale (mCSU). There was no significant difference in the pain scores between the two groups, but the pain scores with both pain scales were significant higher (p < 0,001 for both) six hours compared to one and 20 hours postoperative. Cut-off value on the pain scales (necessitating rescue analgesia) was exceeded in 34,5 % for mGCPS and in 39,5 % for mCSU. Cats with a higher pain score showed a lower food intake (p .