Changes of Vital Parameters after Administration of Butorphanol during Tiletamine- zolazepam-ketamine-xylazine Anaesthesia for Joint Surgery in Miniature Pigs

Raušer P., L. Lexmaulová, R. Srnec, J. Lorenzová, H. Kecová, M. Crha, T. Fichtel, R. Novotná, M. Dvořák, A. Nečas: Changes of Vital Parameters after Administration of Butorphanol during Tiletamine-Zolazepam-Ketamine-Xylazine Anaesthesia for Joint Surgery in Miniature Pigs. Acta Vet. Brno 2008, 77: 251-256. The study compares the effects of butorphanol in pigs undergoing joint surgery in tiletamine-zolazepam-ketamine-xylazine (TKX) anaesthesia. A total of 12 pigs were divided into 2 groups by 6 animals BUT (anaesthetized with TKX combination and butorphanol) and CON (control group anaesthetized with TKX combination only). All pigs were sedated with a mix of tiletamin-zolazepam-ketamin-xylazin, put into total anaesthesia using propofol, and connected to an anaesthesiology unit (O2-Air). For 40 min we logged the heart rate (HR), respiratory rate (RR), mean arterial pressure (MAP), haemoglobin saturation by oxygen (SpO2) and end-tidal CO2 concentration (ETCO2) values. Ten minutes after connecting to the devices, the pigs in the BUT group were intravenously administered butorphanol (0.2 mg/kg) in the total volume of 2 ml, or physiological saline in the same volume. The pigs in the BUT group had a lower (p < 0.05) HR in 5th, 10th and 25th min, and a lower RR in the 10th, 15th and 20th min. MAP, ETCO2 and SpO2 values did not differ substantially. Butorphanol can thus be identified as a suitable analgesic TKX supplement to anaesthesia of miniature pigs with minimum effect on vital functions. Tiletamine-zolazepam, xylazine, ketamine, analgesia, cartilage lesion Joint surgeries are very painful. High-quality balanced analgesia is thus the main prerequisite for correctly managed anaesthesia (Gaynor and Muir 2002). Butorphanol is a mixed opioid agonist/antagonist (Pachter and Evens 1985) with quite a good analgesic effect (Pfeffer et al. 1980). It induces weak sedation, with a minimum negative impact on the cardiovascular system. It may cause a mild decrease of the heart frequency and arterial pressure, or respiration depression in animals (Greene et al. 1990; Trim 1983), which, however, is lower compared to morphine (Trim 1983; Hosgood 1990). Butorphanol effects become apparent within several min after intravenous administration. It remains in effect for approximately 2 4 h (Hosgood 1990). The TKX combination (Henrikson et al. 1995) produces good anaesthesia in pigs, characterized by reliable and rapid induction and good cardiovascular function. These characteristics are very useful in laboratory environment, as easy handling to avoid stress is necessary for research. However, TKX did not provide superior analgesia. This is why we recommend potentiating analgesia with concurrent administration of suitable analgesics, e.g. butorphanol. The effects of butorphanol administered in total anaesthesia combined xylazine-ketamine (Nishimura et al. 1992), tiletamine-zolazepam-xylazine (Ko et al. 1998), azaperoneketamine and detomidine-ketamine (Brodbelt and Taylor 1999), xylazine-ketamine ACTA VET. BRNO 2008, 77: 251-256; doi:10.2754/avb200877020251 Address for correspondence: MVDr. Petr Raušer, Ph.D. Small Animal Clinic University of Veterinary and Pharmaceutical Sciences Palackého 1/3, 612 42 Brno Czech Republic Phone: +420 541 562 362 E-mail: [email protected] http://www.vfu.cz/acta-vet/actavet.htm