Evaluation of fentanyl- ketamine- midazolam combination for anesthesia of New Zealand white rabbits: a randomized controlled study

Different combinations were examined for rabbit’s anesthesia. To the best of our knowledge, the combination of ketamine-midazolam-fentanyl has never been used in rabbits. We assumed this will provide several advantages compared with the previously used combinations. The aim of this study was to evaluate the effects of three different anaesthetic combinations (Ketamine/ Midazolam/ Fentanyl, Ketamine/ Xylazine/ Midazolam and Ketamine/ Xylazine) on nociceptive reflexes, circulatory and respiratory functions, and stress markers, in a New Zealand White rabbit; a commonly used model in experimental urological procedures. The rabbits were randomly assigned into 3 groups (n=24 rabbits): Ketamine/ Midazolam/ Fentanyl (K-M-F) group by (35, 1, 0.02 mg/kg respectively), Ketamine/ Xylazine/ Midazolam (K- X- M) group by (35, 5, 1mg/kg respectively) and ketamine/ Xylazine (K- X) group by (50, 10 mg/kg respectively). Sleep time was significantly earlier and longer in K-M-F but surgical anesthesia was poorest. Bradycardia produced by K-M-F was insignificant in contrast to the other two groups. The effect on stress markers was insignificant. In coclusion, although the addition of fentanyl to ketamine-midazolam combination did not improve the anesthetic quality, but, may be advantageous in anesthesia of circulatory compromised cases, otherwise, other anesthetic combinations should be considered.