Use of xylazine and ketamine in the induction of halothane anesthesia in dogs]

Our experience of the administration of xylazine and ketamine for an induction of halothane inhalation anaesthesia in dogs is described in this paper. After this procedure had been evaluated in 10 test dogs, the xylazine-ketamine induction was used for different surgical interventions in 160 patients. After joint i.m. atropine (0.05 mg/kg) and xylazine (1.5-2 mg/kg) pre-medication general anaesthesia of the dogs was induced by an i.v. administration of 1% ketamine (2 mg/kg). After intubation and anaesthetizer connection halothane vapours had to be applied for 2 to 8 minutes at a 2.5% to 3.5% concentration to induce the tolerance stage of anaesthesia. Then the anaesthesia level was maintained by an application of halothane vapours at a 0.5 to 1.5% concentration (Tab. I). In addition to an evaluation of the anaesthesia proper, breathing-rate, inspiratory and expiratory volumes, internal body temperature were recorded, ECG was made and venous blood samples were taken to evaluate acid-base balance changes. The processing of the obtained data (Figs. 1 to 5, Tab. II) revealed a transient breathing attenuation after the xylazine-ketamine induction and partly compensated respiratory acidosis. On the basis of our results this tested method can replace the traditional thiopental induction associated with the risks of cardiopulmonary depression, or even blood circulation stoppage.