Evaluation of Continuous Propofol Infusion in Xylazine/medetomidine and Butorphanol Premedicated Canine Orthopaedic Patients

Twelve canine orthopaedic patients were randomly divided into 2 groups X (xylazine) and M (medetomidine). Atropine @ 0.04 mg/kg body wt. IM was administered in all animals, followed 5 minutes later by xylazine (0. 5 mg/kg body wt. IV) and butorphanol (0.02 mg/kg body wt. IV) in group X (n=6), whereas, in group M (n=6) medetomidine (10μg/kg body wt. IV) and butorphanol (0.02 mg/kg body wt. IV) were used for premedication. Induction and maintenance of anaesthesia was done by propofol. Ketoprofen was administered both preoperatively and postoperatively for five days. Pedal, palpebral, corneal reflexes and jaw tone abolished earlier in group M than group X. The induction dose of propofol in group M (1.76 ± 0.42 mg/kg) was significantly (P<0.05) lower than in group X (3.61 ± 0.75 mg/kg). The rate of infusion of propofol for maintenance in group M (0.26 ± 0.08 mg/kg/min) was also significantly (P<0.05) lower as compared to group X (0.41 ± 0.10 mg/kg/min). Both preanaesthetic combinations decreased heart rate and respiratory rate; propofol caused tachycardia and depression in respiratory rate and SpO2. MAP increased after preanaesthetic administration in group M but decreased in group X. Propofol also caused slight hypotension. Neutrophilia was recorded in group X. Glucose and cortisol increased during the procedure in both groups. TIVA using xylazine/medetomidine-butorphanolpropofol produces good muscle relaxation and analgesia and may be used in distressed canine orthopaedic patients safely with minimum side effects. However, medetomidine combination had more dose sparing effect on propofol.