Reversible Anesthetic Combination Using Medetomidine Butorphanol-Midazolam (MBMZ) in Cheetahs (Acinonyx jubatus)
Maud Lafortune1,3, DMV, MSc, DACZM; Cornelia Gunkel1, Dr. Med. Vet; Alexander Valverde1, DVM, DVSc, DACVA; Lin Klein2, VMD, DACVA; Scott B. Citino3, DVM, DACZM
1College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; 2School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, USA; 3White Oak Conservation Center, White Oak Road, Yulee, FL, USA
Thirteen captive cheetahs (Acinonyx jubatus) were immobilized for annual routine examination. The cheetahs were given 35±3.7 μg/kg of medetomidine (MED) + 0.2±0.02 mg/kg of butorphanol (BUT) and 0.15±0.02 mg/kg of midazolam (MID) intramuscularly (MBMz).
Once recumbent, the cheetahs were transported to the hospital and physiologic data were measured every 5 min for 60 min (HR, RR, SpO2, blood pressure, end-tidal CO2, and temperature) while breathing room air. Weight, EKG, arterial blood gases and cardiac output were also measured. If arousal occurred before 60 min, a ketamine supplement was given intravenously. After this time, isoflurane was administered and annual examination procedures were performed. At the end of the procedures, atipamezole (175 μg/kg), flumazenil (6 μg/kg), and naltrexone (0.25 mg/kg) were given intramuscularly.
This combination produced a fast and smooth induction (5±1 min), adequate sedation for transport and minor procedures (MBMz anesthesia time 70±16 min), and quick recovery. Hypertension occurred in all animals. Ventilation and oxygenation were good on room air (SaO2 91.7±2.5%, PCO2 39.4±4.5 mm Hg). Pulse oximetry and mucous membrane coloration were not useful for evaluating blood oxygenation with MBMz combination (pale mucous membranes and falsely low SpO2 values).
MBMz combination seems ideal for field procedures where oxygen may not be readily available and quick recovery and release are desired. It is recommended for short procedures (≤40 min), due to sudden arousal that may occur after that time. For longer procedures, supplemental drugs are recommended (injectable agents or isoflurane in oxygen). Finally, this ketamine-free combination may be beneficial for animals with liver/kidney dysfunction, in which the metabolism and excretion of ketamine may be impaired.