Clinical efficacy and safety of dexmedetomidine and buprenorphine, butorphanol or diazepam for canine hip radiography

OBJECTIVES: To investigate the usefulness of dexmedetomidine for restraint and sedation during hip radiographic examination of hip-extended or stress-radiography views when combined with either buprenorphine, butorphanol or diazepam. METHODS: One hundred and twenty-seven client-owned clinically healthy golden retrievers or rottweilers were enrolled in a clinical trial that compared hip-extended and PennHIP methods for diagnosing hip dysplasia and were randomly allocated to receive dexmedetomidine or medetomidine in combination with buprenorphine, butorphanol or diazepam. Subjective assessments were made for response to pain, response to noise, palpebral reflex, muscle tone and overall quality of sedation; non-invasive physiological variables were also recorded. RESULTS: Overall quality of sedation was graded as good or excellent for dogs administered with a combination of butorphanol or diazepam. However, more dogs that received a combination involving buprenorphine had overall a relatively poorer quality of sedation and required additional administration of buprenorphine before the radiographic procedure could commence. Once sedated, clinically sufficient muscle relaxation accompanied by a very low proportion of dogs responding to pain or noise stimuli were observed in all treatment groups. Heart and respiratory rate, and procedure and recovery times were similar for all treatment groups, and no adverse events were observed during the study. CLINICAL SIGNIFICANCE: Dexmedetomidine sedative protocols, particularly in combination with butorphanol and diazepam, can be used effectively and safely in dogs for radiographic procedures.