Effect of xylazine and ketamine on blood pressure, heart rate and respiratory rate in rabbits.

New Zealand white and New Zeland white-Dutch Belted cross rabbits of both sexes were anesthetized using xylazine and ketamine alone and in combination while blood pressure, heart and respiratory rates were monitored. Blood pressure effects were measured from the aortic arch by a cannula implant through the left carotid artery. Ketamine-xylazine in combination at 35 and 5 mg/kg body weight, respectively, produced 45-60 minutes of surgical plane anesthesia. Anesthesia was induced in approximately 10 minutes. The average initial blood pressure drop was complete in 10 minutes and was 30%. Heart and respiratory rates dropped 19% and 77%, respectively, in the same time span. An additional blood pressure drop of 6-7% occurred as consciousness was regained. Blood pressure recovery was nearly complete (normal) about 6 hours following injection of the drug combination.