Effects of total intravenous anesthesia using ketamine and propofol combinations on physiological and anesthetic parameters in xylazine-premedicated mixed-breed dogs

Abstract

The physiological effects of total intravenous anesthesia (TIVA) using three different combinations of ketamine and propofol (“ketofol”) at 1:1 (KP1), 1:2 (KP2) and 1:3 (KP3) in nine xylazine-premedicated adult mixedbred dogs were assessed. The dogs weighing 13.6 ± 2.7 kg were divided into three treatment groups in a repeated crossover experiment. A single bolus injection was used for induction, whereas constant rate infusion (CRI) was utilized for maintenance of anesthesia. All combinations lowered the respiration rates with no variations among the protocols (p=0.197). Within protocols, the rate was significantly lower than the preinduction values at the 30th (p=0.019) and 40th (p=0.041) minutes in KP1 and at the 30th minute (p=0.038) in KP2. The pulse rate was within the normal physiological range, with no differences between protocols (p=0.062); however, within protocols, the rate was significantly lower after the 30th minute in KP1 and after the 15th minute in KP2 postinduction. The temperature was within the normal physiological range but relatively higher in KP1 (p<0.001), with no differences among the protocols during maintenance (p=0.925). The oxygen saturation was generally low and did not differ significantly among the groups (p=0.542). The induction and recovery qualities were rapid and smooth, respectively, in all treatments. In all the treatments, apneustic breathing was the most common side effect. In conclusion, all ketofol ratios can be used in mixedbred dogs; however, the 1:3 (KP3) combination had relatively more stable physiological parameters, fewer side effects and quicker recovery.