Abstract

Total intravenous anesthesia (TIVA) is widely being used in veterinary medicine due to its rapid induction, improved cardiopulmonary effects, and fast recovery time. Two different fentanyl-propofol protocols, fentanyl-propofol TIVA (FP-CRI) and fentanyl-propofol-isoflurane (PF-I), were compared for the maintenance of anesthesia in six fentanyl-propofol induced adult captive cheetahs (Acinonyx jubatus). Both groups were induced, in a squeeze cage, with 2 ug/kg of fentanyl (Baxter, Deerfield, IL, USA) and 5.0-6.5 mg/kg of propofol (Abbott, Chicago, IL, USA) IV to effect, followed by endotracheal intubation. Group A (n=3) was maintained on a constant rate of infusion (CRI) of 0.1-0.2 ug/kg/m fentanyl and 0.05-0.2 mg/kg/m propofol IV; whereas Group B (n=3) was maintained on 2-5% isoflurane (MWI Veterinary Supply, Meridian, ID, USA). Length of anesthesia was similar in both groups. Physiologic variables measured included heart rate, respiratory rate, tidal volume, oxygen-hemoglobin saturations, end-tidal CO₂, arterial blood gases, and rectal temperature. Induction time, muscle relaxation, and time and quality of recovery were assessed. The combination of fentanyl and propofol provided smooth IV induction in all six cheetahs while the FP-CRI and FP-I protocols both provided a safe and effective maintenance of anesthesia throughout their procedures. Intermittent apneic episodes were seen with FP-CRI combination and improved with intermittent positive pressure ventilation. Blood pressures were mildly decreased with PF-I protocol. Recovery times were prolonged in cheetahs receiving FP-CRI when compared with the FP-I protocol. Due to prolonged recovery times, we recommend that for procedures lasting more than 20 minutes, anesthesia is maintained with isoflurane.