Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Jan B. Thomas x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective

To characterize isoflurane (ISO)-induced anesthesia in ferrets and rats.

Animals

8 ferrets (Mustela putorius furo) and 8 Sprague-Dawley rats.

Procedure

Ferrets and rats were anesthetized in a similar manner, using ISO in oxygen. Minimum alveolar concentration (MAC) was determined, using the tail-clamp method. Immediately thereafter, assessments were recorded for 0.8, 1.0, 1.5, and 2.0 MAC (order randomized) of ISO.

Results

MAC of ISO was (mean ± SEM) 1.74 ± 0.03 and 1.58 ± 0.05% for ferrets and rats, respectively. Mean arterial blood pressure (MAP) was 75.0 ± 4.3 and 107.9 ± 2.7 mm Hg at 0.8 MAC for ferrets and rats, respectively, and decreased in a parallel dose-dependent manner. Respiratory frequency decreased in rats as ISO dose increased; however, respiratory frequency increased in ferrets as ISO dose increased from 0.8 to 1.5 MAC but then decreased at 2.0 MAC. At 0.8 MAC, hypoventilation was much greater in ferrets (Paco2 = 71.4 ± 3.5 mm Hg), compared with rats (Paco2 = 57.7 ± 1.9 mm Hg). In both species, Paco2 progressively increased as anesthetic dose increased. Eyelid aperture of ferrets increased in a dose-dependent manner. Pupil diameter in ferrets and rats increased as ISO dose increased.

Conclusions and Clinical Relevance

The MAP and Paco2 in ferrets and rats and eyelid aperture in ferrets consistently and predictably changed in response to changes in anesthetic dose of ISO. Magnitude of respiratory depression was greater in ferrets than rats. Changes in MAP and Paco2 in ferrets and rats and eyelid aperture in ferrets are consistent guides to changes in depth of ISO-induced anesthesia. (Am J Vet Res 1999;60:1577–1583)

Free access
in American Journal of Veterinary Research

Abstract

Objective

To characterize variables used to monitor rabbits during inhalation anesthesia.

Animals

8 male New Zealand White rabbits.

Procedure

Rabbits were similarly anesthetized with halothane (HAL) or isoflurane (ISO) in a crossover study; half received HAL followed by ISO, and the protocol was reversed for the remaining rabbits. After induction, minimum alveolar concentration (MAC) was determined for each agent, using the tail-clamp method, and variables were recorded at 0.8, 1.0, 1.5, and 2.0 MAC (order randomized).

Results

Mean ± sem mac was 1.42 ± 0.05 and 2.07 ± 0.09% for hal and iso, respectively. Directly measured auricular mean arterial blood pressure was 52.8 ± 5.6 and 54.8 ± 6.1 mm Hg at 0.8 mac for hal and iso, respectively, and decreased from these values in a parallel dose-dependent manner. Respiratory frequency remained constant (range, 69 to 78 breaths/min) over the range of hal doses but incrementally decreased from a mean of 53 (at 0.8 mac) to 32 breaths/min (at 2.0 mac) for iso. The Paco2 was similar at 0.8 mac for hal and iso and progressively increased with increasing doses of both agents; Paco2 at 2.0 mac for iso was significantly greater than that at 2.0 mac for hal (79.8 ± 13.7 vs 54.9 ± 4.0 mm Hg, respectively). Eyelid aperture consistently increased in a dose-dependent manner for both anesthetics.

Conclusions

Arterial blood pressure, Paco2, and eyelid aperture consistently and predictably changed in rabbits in response to changes in anesthetic doses. The magnitude of respiratory depression was greater for iso than for hal. (Am J Vet Res 1999;60:1189–1195)

Free access
in American Journal of Veterinary Research

Abstract

Objective—To assess selenium (Se) status of cats in 4 regions of the world and to compare results for Se status with reported incidence of hyperthyroidism in cats in those regions.

Animals—50 cats (30 from 2 regions with an allegedly high incidence of hyperthyroidism and 20 from 2 regions in which the disease is less commonly reported).

Procedure—Hematologic samples (heparinized whole blood, plasma, and RBC fractions) were obtained from 43 healthy euthyroid cats and 7 hyperthyroid cats. Plasma concentration of Se and activity of glutathione peroxidase (GPX) in whole blood and plasma were determined.

Results—Plasma concentration of Se and GPX activity in whole blood or plasma did not differ significantly among cats from the 4 regions. However, cats had a plasma concentration of Se that was approximately 10 times the concentration reported in rats and humans. The GPX activity in whole blood or plasma in cats generally was higher than values reported in rats or humans.

Conclusions and Clinical Relevance—Cats have higher Se concentrations in plasma, compared with values for other species. However, Se status alone does not appear to affect the incidence of hyperthyroidism in cats. High Se concentrations may have implications for health of cats if such concentrations are influenced by the amount of that micronutrient included in diets. (Am J Vet Res 2001;62:934–937)

Full access
in American Journal of Veterinary Research