Evaluation of buprenorphine as optimisation of postoperative analgesia in feral cats undergoing ovariohysterectomy under field conditions

Objectives: The objective of this prospective, randomised, blinded, observational clinical study was to investigate the effect of subcutaneously administered buprenorphine on postoperative pain in female feral cats undergoing ovariohysterectomy as part of a trap‐neuter‐return programme. The aim was to determine whether buprenorphine can prevent pain scores from exceeding established intervention thresholds postoperatively – a problem identified in a previous study using the same anaesthetic protocol. Materials and Methods: A total of 115 cats were anaesthetised with an intramuscular protocol comprising medetomidine, ketamine and butorphanol, in combination with a nonsteroidal anti‐inflammatory drug (meloxicam). Prior to anaesthesia induction, cats were randomly assigned to either receive 0.02 mg/kg buprenorphine (BUP group) or an equal volume of saline (NaCl 0.9%) (control group) subcutaneously at the end of surgery. Pain was assessed at 3, 6 and 24 hours postoperatively using the validated feline Glasgow Composite Measure Pain Scale. Results: Subcutaneous administration of buprenorphine at the end of surgery did not significantly reduce postoperative pain scores or prevent values from exceeding the clinical intervention threshold compared to saline. Although numerical differences were observed at specific time points, pain trajectories over time were similar between groups. Notably, overall and independently of the group 34.5% of cats exceeded the intervention threshold at 3 hours and 38.8% at 6 hours postoperatively, underscoring the need for improved analgesic strategies during the early postoperative period in trap–neuter–return settings. Clinical Significance: These findings suggest that a single subcutaneous dose of buprenorphine may not consistently enhance analgesia over standard multimodal protocols under field conditions.