Effects of Ketamine on Carfentanil and Xylazine Immobilization of White-Tailed Deer (Odocoileus Virginianus)

Abstract

Using a crossover design, the effects of the addition of ketamine to a previously determined optimal hand-injected immobilization dosage of carfentanil/xylazine were evaluated in 11 adult white-tailed deer (Odocoileus virginianus). Two i.m. ketamine dosages were evaluated: 0.15 mg/kg (low ketamine) and 0.30 mg/kg (high ketamine). Each deer was immobilized twice 2 wk apart. Inductions were video recorded and reviewed by observers, who had been blinded to drugs and dosages, who rated qualitative aspects. There were significant (P < 0.05) dosage-dependent decreases in heart rate, SaO2, and arterial pH, and a significant dosage-dependent increase in PaCO2. Induction times with both dosages were more rapid (mean 2.3 +/- 0.9 min for low ketamine and 2.3 +/- 0.6 min for high ketamine) than those reported for the same carfentanil/xylazine dosage used without ketamine. Mean quality ratings, though improved compared to those reported for carfentanil/xylazine alone, were considered "undesirable" for both dosages. Hyperthermia (temperature > 41 degrees C) was noted in 13 of 22 immobilizations. Arterial pH and PaO2 increased significantly from 10 to 20 min postrecumbency, but acidemia (pH < 7.3) was present throughout immobilization periods for all deer. There were ketamine dosage-dependent increases in respiratory components of this acidemia compared with that associated with carfentanil/xylazine alone. Possible hypoxemia was present at both sampling times for both groups, while hypercapnea (PaCO2 > 60 mm Hg) was present for the high-ketamine group only. Reversal times for naltrexone and yohimbine were rapid (mean 2.9 +/- 0.7 min for low ketamine and 3.3 +/- 0.8 min for high ketamine), with no evidence of renarcotization. Although the addition of ketamine to carfentanil/xylazine caused faster inductions and improved induction qualities, it also produced an increased incidence of hyperthermia, acidemia, hypoxemia, and hypercapnea. Supplemental oxygen and close monitoring of body temperature is recommended when using this immobilization regimen.

Immobilization of white‐tailed deer with telazol, ketamine, and xylazine, and evaluation of antagonists

“…During our study, the temperature of 3 animals immobilized with TKX exceeded 41° C. High initial temperature likely was a result of physical exertion that occurred when darted males were pursued by other males in our facility. One male in our study was gored by another and had an initial rectal temperature of 42° C. Despite those instances, initial rectal temperatures (38.9° C) and those immediately prior to antagonist administration (38.6° C), were comparable to or less than mean values reported for other drug combinations with white‐tailed deer (range: 39.2–42.1° C; Miller et al 2003, 2009; Storms et al 2005, 2006; Muller et al 2007).…”

“…To avoid violent inductions and recoveries when cyclohexanes are used independently, adding alpha 2 ‐adrenergic agonists (e.g., xylazine) provides sedation, analgesia, myorelaxation, and better inductions and recoveries (Millspaugh et al 1995, Walsh and Wilson 2002). Ketamine, another cyclohexane, is frequently used in combination with opioid and alpha 2 agonists to decrease total drug required, improve muscle relaxation, and reduce hyperthermia (Citino et al 2001, 2002; Grobler et al 2001; Storms et al 2006), or as a supplemental drug to prolong anesthesia (Murray et al 2000).…”

“…A combination of TKX has been successfully used to immobilize domestic cats ( Felus catus ), sheep ( Ovis aries ), pigs ( Sus scrofa ), and cheetahs ( Acinonyx jubatus ; Thurmon et al 1988, Ko et al 1993, Lewandowski et al 2002, Williams et al 2002, Cistola et al 2004), but it has not been evaluated for cervids. The combination may offer advantages to TX or KX immobilization of white‐tailed deer, but recovery times for telazol combinations are often lengthy (Miller et al 2004), especially compared with ketamine combinations (Mech et al 1985, Storms et al 2006, Muller et al 2007). Although no complete antagonists for the cyclohexanes exist, yohimbine and tolazoline may have partial antagonistic qualities (Kreeger and Seal 1986).…”

Drug Residues after Intravenous Anesthesia and Intrathecal Lidocaine Hydrochloride Euthanasia in Horses

“…Lidocaine hydrochloride also was found in skeletal muscle from horses anesthetized by routine dosages. Although all drugs including lidocaine were widely distributed throughout various tissues, the concentrations were far below the concentrations reported to have sedative, much less, toxic effect . The muscle groups selected for sampling represent large skeletal muscle masses that likely would make up most of the mass consumed by a carnivore, scavenger, or scavenging human.…”

“…Limited information is available about the toxicity of xylazine, ketamine, midazolam, and lidocaine in various species . Furthermore, no information is available about the effects of these drugs (such as sedation) on scavenging animals.…”