Evaluation of hemodynamic, hematological parameters and the clinical effects of dexmedetomidine-ketamine and xylazine-ketamine anesthesia in rabbits

With this study, it was aimed to assess the effects of experimentally induced dexmedetomidine-ketamine (DK) and xylazine-ketamine (XK) combinations on clinical parameters and hemodynamic and hematological parameters in rabbits. In the study, 16 male New Zealand breed rabbits were divided into two groups. Group DK (n = 8) was administered dexmedetomidine (25 mu g/kg) and ketamine (30 mg/kg) in the same injector, and Group XK (n = 8) was administered xylazine (4 mg/kg) and ketamine (30 mg/kg) in the same injector through the intramuscular (IM) route. Following the injection, the rabbits' reflexes were tested approximately every 30 s. Hemodynamic parameters were determined before the injection (0 min) and 5, 10, 15, 30, 45, 60, 75, 90, 105 and 120 min after the anesthetic combinations were injected. Furthermore, blood gas and electrolyte values were analyzed before, during and after anesthesia. The differences between the groups were not statistically significant in terms of the loss and return times of the righting reflex, ear-pinch reflex and pedal withdrawal reflex (P > 0.05). The mean surgical anesthesia duration was determined as 115 min in the DK group and 116.5 min in the XK group. In both groups, the heart rate (HR), repiratory rate (RR), mean arterial pressure (MAP) and arterial oxygen saturation of hemoglobin (SpO(2)) decreases. In the statistical analysis, the differences between the groups were statistically significant in terms of HR at the 5th, 10th and 15th min and in terms of SpO(2) at the 120th min (P < 0.05). In the DK group, the change in RR based on the pre-injection time (0 min) was found significant (P < 0.05). In the statistical analyses on the arterial blood gases and electrolyte findings, the differences between the DK and XK groups were insignificant in terms of pH, pCO(2) and pO(2) (P > 0.05) and significant in terms of only glucose (mg/dL) at the 5th min (P < 0.05). Consequently, it was observed that the DK and XK combinations had similar effects in healthy adult rabbits regarding the reflex findings, anesthesia duration and hemodynamic and hematological parameters. It was concluded that, to prevent hypoxemia related to RR decrease in the combination of alpha 2 adrenergic agonists and ketamine, there is a need for oxygen reinforcement starting with the induction of anesthesia, and the DK combination needs to be used carefully in patients with respiratory depression.