INTRANASAL (IN) ADMINISTRATION OF DEXMEDETOMIDINE AND BUTORPHANOL: A PRELIMINARY STUDY IN DOGS

Aim of this study was to assess in dogs the sedative effects of the intranasal administration (IN) of Dexmedetomidine alone or combined with Butorphanol. Materials and Methods: N. 20 dogs of different breeds, ASA I or II, undergoing sedation were included in the study. Written consent was obtained by the owners. Baseline measurements of T°C, RR, HR, NIBP and SPO2 were recorded noninvasively (Mindray PM-9000 Express®) at T-0 and every 5 minutes after treatment. Dogs were then randomly assigned to one of two groups receiving either Dexmedetomidine (Dexdomitor® Pfizer 20 µg/kg = group D) or Dexmedetomidine (10 µg/kg) mixed with Butorphanol (Dolorex® Intervet 0.1 mg/kg = group DB). The drug/s were administered IN by a Mucosal Atomization Device (MAD® Wolfe Tory Medical, inc.). A blinded observer assessed onset, duration and degree of sedation every 5 minutes using a numerical scoring system (maximum sedation score [SS] = 10). Total SS at each time point of the two groups were compared using Pearson???s ??2. Clinical parameters were processed by repeated measures MANOVAs followed by post hoc Tukey???s HSD test to explore differences between single time points (P??? 0.05). Results: IN drug absorption was excellent and comparable to IM injection in all cases (onset = 12.6???± 5???). Total SS was significantly higher in Group D (mode 9) compared to group DB (mode 8) (P=0.004). Mean blood pressure was significantly higher in Group D at T15, T20, and from T30 to T45 (P???0.01). No significant differences in SPO2, HR and RR were found between the two groups at all times after premedication. No undesirable effects were observed in any of the dogs. Conclusions: IN administration of sedative drugs is a widespread procedure in human adults and children and an attractive target in animals. A direct drug transport pathway from the nasal cavity to the brain has been shown. Nasal administration of diazepam has been reported in dogs as means of emergency treatment for seizures, resulting in a rapid and efficient absorption. Intranasal dexmedetomidine and opioids have been reported for sedation in children along with reversal agents. The use of the MAD® device improves drug distribution on mucous membranes, resulting in an easy, efficient and painless administration procedure. The present study endorse IN administration of Dexmedetomidine and Butorphanol for routine clinical use in dogs.