Enflurane and isoflurane have been proposed as reasonable alternatives to halothane for the anesthetic management of the horse. Although both agents are chemically similar to methoxyflurane, their physical properties and clinical characteristics more closely resemble those of halothane. Clinical and laboratory evaluations in horses showed that both enflurane and isoflurane induced general anesthesia. Induction of anesthesia and emergence from anesthesia were generally rapid and smooth. Postanesthetic complications were not observed. Hypoventilation was induced by both agents. The magnitude of rise of arterial CO2 tension was anesthetic-concentration dependent. Cardiovascular depression with enflurane and isoflurane paralleled anesthetic dose. However, compared with equipotent concentrations of enflurane, reductions of cardiovascular function appeared less during isoflurane anesthesia. Except for the deepest levels of enflurane anesthesia, cardiac rhythm was stable with both agents. Occasional abnormal muscle twitching or seizure-like movements of the extremities were observed during anesthesia induced by enflurane but not by isoflurane. The severity of these movements was related directly to anesthetic dose. From these initial observations in healthy horses, it appears that both enflurane and isoflurane may be used as inhalant anesthetics for the horse; however, isoflurane is probably better tolerated by the horse over a wider range of anesthetic doses.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of the American Veterinary Medical Association|
|State||Published - Jan 1 1978|
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