Efeito hipnótico do etomidato associado à clorpromazina e à xilazina em Rattus norvegicus.

Abstract

In the last two decades the anesthetic techniques for laboratory animals (mice, rats, guineapigs and rabbits) have been limited to the use of phenobarbital associated or not with pre-anesthetic medication such as chlorpromazine, levomepromazine, flunitrazepam (tranquilizers) or dissociate anesthetics such as quetamine associated with atropine (anticholinergic) and xilazine (sedative, analgesic and muscle relaxant). Etomidate, a non-barbiturate hypnotic recently introduced in veterinary, has been used in dogs and cats. The objective of this work was to determine the hypnotic dose of the etomidate (DE5O) in rats and to evaluate that dose in association with pre-anesthetics such as chlorpromazine or atropine and xilazine. Groups of 10 and 15 rats received intraperitoneal 3 to 7 mg/kg of etomidate. Time of hypnosis was 241 + 0.36 minutes. The intraperitoneal injection of DE5O (4.19 mg/kg) from etomidate in rats previously treated with chlorpromazine (5mg/kg, IP) or atropine (0,44 mg/kg. SC) and xilazine (20 mg/kg, IP) showed that both associations produced a long hypnosis, 7.18 + 0,22 and 20,20 + 1,44 minutes, respectively. Hypnosis was long with the association atropine + xilazine + etomidate, suggesting a better synergic effect among these drugs. These studies suggest that the etomidate associated with chlorpromazine or atropine and xilazine can be considered a new anesthetic option for procedures of short duration in rats