Analgesic effects of gabapentin and buprenorphine in cats undergoing ovariohysterectomy using two pain-scoring systems: a randomized clinical trial

Objectives The aim of the study was to evaluate the analgesic efficacy of gabapentin–buprenorphine in comparison with meloxicam–buprenorphine or buprenorphine alone, and the correlation between two pain-scoring systems in cats. Methods Fifty-two adult cats were included in a randomized, controlled, blinded study. Anesthetic protocol included acepromazine–buprenorphine–propofol–isoflurane. The gabapentin–buprenorphine group (GBG, n = 19) received gabapentin capsules (50 mg PO) and buprenorphine (0.02 mg/kg IM). The meloxicam–buprenorphine group (MBG, n = 15) received meloxicam (0.2 mg/kg SC), buprenorphine and placebo capsules (PO). The buprenorphine group (BG, n = 18) received buprenorphine and placebo capsules (PO). Gabapentin (GBG) and placebo (MBG and BG) capsules were administered 12 h and 1 h before surgery. Postoperative pain was evaluated up to 8 h after ovariohysterectomy using a multidimensional composite pain scale (MCPS) and the Glasgow pain scale (rCMPS-F). A dynamic interactive visual analog scale (DIVAS) was used to evaluate sedation. Rescue analgesia included buprenorphine and/or meloxicam if the MCPS ⩾6. A repeated measures linear model was used for statistical analysis (P <0.05). Spearman’s rank correlation between the MCPS and rCMPS-F was evaluated. Results The prevalence of rescue analgesia with a MCPS was not different (P = 0.08; GBG, n = 5 [26%]; MBG, n = 2 [13%]; BG, n = 9 [50%]), but it would have been significantly higher in the BG (n = 14 [78%]) than GBG (P = 0.003; n = 5 [26%]) and MBG (P = 0.005; n = 4 [27%]) if intervention was based on the rCMPS-F. DIVAS and MCPS/rCMPS-F scores were not different among treatments. A strong correlation was observed between scoring systems (P <0.0001). Conclusions and relevance Analgesia was not significantly different among treatments using an MCPS. Despite a strong correlation between scoring systems, GBG/MBG would have been superior to the BG with the rCMPS-F demonstrating a potential type II error with an MCPS due to small sample size.