Effects of atipamezole on selected physiologic parameters in cynomolgus macaques (Macaca fascicularis).

BACKGROUND: Atipamezole, an α-2 adrenergic receptor antagonist, reverses the α-2 agonist anesthetic effects. There is a dearth of information on the physiological effects of these drugs in cynomolgus macaques (Macaca fascicularis). We assessed atipamezole's physiologic effects. We hypothesized atipamezole administration would alter anesthetic parameters. METHODS: Five cynomolgus macaques were sedated with ketamine/dexmedetomidine intramuscularly, followed 45 min later with atipamezole (0.5 mg/kg). Anesthetic parameters (heart rate, blood pressure [systolic (SAP), diastolic (DAP), and mean (MAP) blood pressure], body temperature, respiratory rate, and %SpO2) were monitored prior to and every 10 min (through 60 min) post atipamezole injection. RESULTS: While heart rate was significantly increased for 60 min; SAP, DAP, MAP, and temperature were significantly decreased at 10 min. CONCLUSIONS: This study indicates subcutaneous atipamezole results in increased heart rate and transient blood pressure decrease. These findings are clinically important to ensure anesthetist awareness to properly support and treat patients as needed.

Comparison of rectal and tympanic core body temperature measurement in adult Guyanese squirrel monkeys (Saimiri sciureus sciureus).

BACKGROUND: Measuring core body temperature in a manner that is safe for animals and veterinary personnel is an important part of a physical examination. For nonhuman primates, this can involve increased restraint, additional stress, as well as the use of anesthetics and their deleterious effects on body temperature measurements. The purpose of this study was to compare two non-invasive methods of infrared tympanic thermometry to standard rectal thermometry in adult squirrel monkeys. METHODS: Tympanic temperatures were collected from 37 squirrel monkeys and compared to rectal temperatures using a human and veterinary infrared tympanic thermometer. RESULTS: Compared with rectal temperature measurements, the human tympanic thermometer readings were not significantly different, while the veterinary tympanic thermometer measurements were significantly higher (P<0.05). There were no differences between sexes. CONCLUSIONS: The tympanic thermometer designed for use in humans can be used in adult squirrel monkeys as an alternative to rectal thermometry for assessing core body temperature.

Postoperative analgesia in dogs receiving epidural morphine plus medetomidine.

This investigation was carried out to compare the postoperative analgesia and plasma morphine concentrations in dogs given epidural morphine or epidural morphine combined with medetomidine prior to surgery. Twelve dogs (seven males and five females) with ruptured cranial cruciate ligaments presented to the Washington State University Veterinary Teaching Hospital. Six dogs received an epidural injection of morphine (0.1 mg/kg) and six dogs received epidural morphine (0.1 mg/kg) combined with medetomidine (0.005 mg/kg). Numeric rating scale (NRS) pain scores and cumulative pain scores (CPS) were assigned to 10-min segments of video. Video segments, heart rates and respiratory rates were recorded prior to premedication and at 4, 8, 12, 18 and 24 h after epidural injection. Blood was sampled from the cephalic vein at each of these times and during anesthesia at 0.5, 1, 2 and 3 h after epidural injection. Data were analyzed using either Friedman's test or one-way anova for repeated measures. In the morphine group, significant increases compared with premedication values were detected at 4, 8 and 12 h after epidural injection for NRS and at 4 and 12 h after epidural injection for CPS. In the morphine plus medetomidine group, NRS was significantly higher at 4 and 8 h whereas there were no differences from baseline values for CPS. Plasma morphine concentrations were not significantly different between treatment groups, but were significantly increased compared with preinjection values at 0.5, 1, 12, 18, and 24 h in the morphine plus medetomidine group. Epidurally administered morphine combined with medetomidine was associated with only minor benefits based on subjective pain scoring when compared with morphine alone in these dogs undergoing repair of a ruptured cranial cruciate ligament.