Sedative and Respiratory Effects of Intramuscular Detomidine and Butorphanol in Donkeys Sedated for Bronchoalveolar Lavage

The aim of this study was to evaluate the effects of intramuscular (IM) detomidine and butorphanol on sedation, arterial blood gases, and bowel motility in sixteen healthy Amiata donkeys undergoing bronchoalveolar lavage (BAL). Before administration of detomidine and butorphanol, baseline values for heart rate (HR), respiratory frequency (fr), rectal temperature, arterial blood gases, and sedation score (range 0-9) were recorded as Tbase and bowel motility was assessed. Sedation was assessed with a composite sedation scale. After IM injection of detomidine 0.06 mg kg−1 and butorphanol 0.05 mg kg−1, HR, fr, temperature, and sedation score were registered every 5 minutes. Arterial blood was sampled when sedation score was greater than or equal to 6 right before performing the diagnostic procedure (T1) and at a sedation score of 3 or lower, which was considered the end of sedation (T2). Bowel motility was assessed every hour after the end of sedation. Sedation score of 6 or more was reached after 10 minutes in all animals. Mean sedation time was 38.8 ± 5.2 minutes. PaO2, HR, and fr were significantly lower at T1 and T2 compared to Tbase values. Fshunt significantly increased at T2, in comparison to Tbase. Time from injection to return to normal bowel motility was 272 ± 62 minutes. Intramuscular detomidine and butorphanol provided satisfactory sedation for BAL in donkeys, in terms of reliability and duration. Clinicians should be aware of the reduction of PaO2 that can arise.