Efficacy of the intranasal route for administration of anesthetic agents to adult rabbits.

Anesthetic agents were administered to adult rabbits by using the intranasal route. Six sedative or anesthetic protocols were studied as follows: group 1 (n = 12), 2.0 mg midazolam/kg body weight (BW); group 2 (n = 8), 25.0 mg ketamine/kg BW; group 3 (n = 8), 10 mg of combination of tiletamine and zolazepam/kg BW; group 4 (n = 10), 3 mg xylazine/kg BW and 10 mg ketamine/kg BW; group 5 (n = 8), 1.0 mg midazolam/kg BW and 25 mg ketamine/kg BW; and group 6 (n = 6), 0.3 ml of a combination of fentanyl and droperidol/kg BW. All drugs were diluted to a final volume of 0.4 ml/kg BW and an equal volume was administered with a catheter-tipped syringe into each nostril. Time to onset and duration of sedation or anesthesia were recorded. Muscle relaxation was graded as poor, fair, or excellent on the basis of flexibility of limbs. Presence or absence of a toe pinch response was recorded. Heart rate, respiratory rate, and hemoglobin saturation were measured before and at 5-min intervals after drug administration. The mean onset times for groups 1, 2, 3, 4, and 5 were 3.0, 1.2, 2.5, 2.0, and 0.8 min, respectively. The mean duration of action was 24.6, 36.7, 44.4, 35.2, and 52.5 min for midazolam, ketamine, tiletamine/zolazepam, xylazine/ketamine, and midazolam/ketamine, respectively. All protocols resulted in a significant decrease in respiratory rate. Hemoglobin saturation decreased in all groups except group 1.(ABSTRACT TRUNCATED AT 250 WORDS)