A comparison of the sedative and analgesic effects of buprenorphine in combination with acepromazine, midazolam or medetomidine in dogs

The effects of buprenorphine in combination with acepromazine, midazolam or medetomidine were compared in dogs. Induction and recovery times, heart rate, respiratory rate and body temperature were measured. Posture, reaction to noise, analgesia and muscle relaxation were assessed and a global score of "sedation-analgesia" was calculated. There were 3 groups of 4 animals: group 1 received 0.1 mg.kg-¹ acepromazine IM and 20 minutes later, 10 g.kg-¹ buprenorphine IV; group 2 received 1 mg.kg-¹ midazolam IV simultaneously with 10 ig.kg-¹ buprenorphine IV and group 3 received 1 mg/m² body surface area medetomidine IM and 20 minutes later, 10 Hg.kg-¹ buprenorphine IV. Only one dog given acepromazine and buprenorphine reached a "sedation-analgesia" stage, denned as the inability to stand together with the absence of reaction to stimulation, including pain. Animals in this group showed a decrease in respiratory rate and in body temperature. None of the dogs given midazolam and buprenorphine became sedated or showed signs of analgesia. Following this combination, the dogs were excited and showed dysphoric reactions which disappeared within 20 minutes.
All of the dogs given medetomidine and buprenorphine showed good sedation and analgesia lasting more than 20 minutes. This drug combination produced a decrease in heart and respiratory rates and body temperature.