Comparison of Dexmedetomidine–Ketamine–Midazolam and Isoflurane for Anesthesia of Black-tailed Prairie Dogs (Cynomys ludovicianus)

Abstract

Few studies evaluate anesthesia in black-tailed prairie dogs (Cynomys ludovicianus). Isoflurane inhalant anesthesia is used in this species most commonly, but injectable protocols are poorly described. Here we compared the physiologic effects, including anesthetic depth, vital signs, and hematologic changes, of anesthetic protocols using isoflurane or a combination of dexmedetomidine, ketamine, and midazolam in black-tailed prairie dogs. In a randomized, complete crossover study design, intact male black-tailed prairie dogs (n = 9; age, 6 mo) were anesthetized by using a combination of dexmedetomidine (0.25 mg/kg IM), ketamine (40 mg/kg IM), and midazolam (1.5 mg/kg IM). For reversal, atipamezole (0.15 mg/kg) and flumazenil (0.05 mg/kg) were administered 45 min after induction. For comparison, isoflurane was administered at 5% in 100% oxygen at 5 L/min in an anesthetic induction chamber, followed by maintenance isoflurane 2% in 2 L/min oxygen through a tightfitting facemask for 45 min. Induction and recovery time, respiratory rate, heart rate, body temperature, SpO 2 , indirect blood pressure, and reflexes were monitored every 5 min during the anesthetic period. Blood samples for venous blood gases, PCV, and refractometric total protein were obtained from the cranial vena cava at 5 min and 45 min. Both protocols appeared to achieve safe and effective anesthesia. Except for blood pressure, all vital signs differed between the 2 treatments. Isoflurane anesthesia resulted in a slightly longer induction and lower respiratory rate and body temperature but increased likelihood of absent reflexes. DKM anesthesia resulted in a faster induction and less hypothermia but also prolonged recovery and lower heart rate and SpO 2 readings. These findings suggest that isoflurane provides a more stable and consistent anesthetic plane, whereas dexmedetomidine-ketamine-midazolam anesthesia may be an effective alternative for short procedures that require fast induction and limited analgesia.

Anesthetic Effects of Alfaxalone–Ketamine, Alfaxalone–Ketamine–Dexmedetomidine, and Alfaxalone–Butorphanol–Midazolam Administered Intramuscularly in Five‑striped Palm Squirrels (Funambulus pennantii)

“…gas abnormalities in palm squirrels under AK, AKD, or ABM anesthesia. 9,52 Regardless of the anesthesia protocol, all squirrels in our study became profoundly hypothermic, with a decreased (mean, 5.5 °C) rectal temperature over the procedure time. Regardless of the drugs used, anesthesia in general can lead to hypothermia.…”

“…1,2,14,39,40,44,47 In general, squirrel species can be fractious in nature, and chemical immobilization or anesthesia is often required to enable examinations or clinical procedures. 5,7,9,16,23,25,30,31,36,37,42,51 With its relatively rapid induction and recovery properties, inhalation anesthesia is commonly used for immobilization of rodent species. 9,20,22,31,37 Because of the small body size of palm squirrels, endotracheal intubation is technically challenging and therefore not routinely performed, and inhalation anesthesia is commonly delivered by using a chamber or face mask.…”

“…5,7,9,16,23,25,30,31,36,37,42,51 With its relatively rapid induction and recovery properties, inhalation anesthesia is commonly used for immobilization of rodent species. 9,20,22,31,37 Because of the small body size of palm squirrels, endotracheal intubation is technically challenging and therefore not routinely performed, and inhalation anesthesia is commonly delivered by using a chamber or face mask. However, the use of a face mask for anesthesia increases the risk of waste gas exposure to personnel.…”

“…11,45 Therefore, alternative protocols that exclusively use injectable anesthetic drugs for the induction and maintenance of anesthesia and that reduce waste-gas exposure are desired. 7,9,22,23 Furthermore, intravascular access is challenging to obtain in palm squirrels; consequently, parenteral, nonvascular protocols may provide the most accommodating route for anesthesia induction and maintenance in this species.…”

Anesthetic effects of alfaxalone-ketamine-midazolam and alfaxalone-ketamine-dexmedetomidine administered intramuscularly in black-tailed prairie dogs (Cynomys ludovicianus)

“…1,2 Inhalant anesthesia has been previously evaluated in black-tailed prairie dogs and can produce a stable plane of general anesthesia. [3][4][5] While gas anesthesia can provide a stable plane of anesthesia after induction, the use of chamber induction creates risk of waste gas exposure to veterinary personnel, has been associated with a greater odds ratio of Anesthetic effects of alfaxalone-ketamine-midazolam and alfaxalone-ketamine-dexmedetomidine administered intramuscularly in black-tailed prairie dogs (Cynomys ludovicianus…”