Use of Ether Anesthesia
Although ether was once a popular anesthesia agent, its use is now strongly discouraged. The use of ether as an anesthetic in research animals must be scientifically justified and approved by the IACUC in the Animal Use Protocol. A number of alternative gaseous anesthetics are commonly available for use in animals, including halothane, isoflurane, and methoxyflurane (which can be used in a bell jar). In addition, for euthanasia CO2 gas is available in each vivarium and most laboratories.
Undesirable Effects of Ether Anesthesia
- Ether is flammable and forms explosive mixtures with oxygen and air.
- Induction is unpleasant for the animal, and the irritant properties of ether can cause coughing, profuse bronchial and salivary secretions and occasional laryngospasm.
- Ether can cause pre-existing, subclinical respiratory disease to develop into acute severe infection following recovery from anesthesia.
- Induction and recovery times for anesthesia are relatively slow.
- Administration of ether stimulates catecholamine release which counter acts the depressant effects of the anesthetic such that blood pressure is maintained at near normal levels at all except deep anesthetic levels. Other metabolic effects include increased glucocorticoid release and increased blood glucose levels (rats) and induction of microsomal enzyme activity.
- "Etherized" animal carcasses are an explosion hazard and storage of such carcasses in refrigerators that are not spark-proof may result in explosions.
Carruba, M.O., Bondiolotti, G.P., Picotti, G.B., Catteruccia, N. and DaPrada, M. (1987). Effects of diethyl ether, halothane, ketamine and urethane on sympathetic activity in the rat. Europ. J Pharmacol, 134, 15-24.
Flecknell, P. (1996) Laboratory Animal Anesthesia, 2nd ed. Academic Press, London.
Perez, L.F., Zamora, S., Rosique, M.J. and Sastre, J.F. (1992) Effects of inhalation of ehtyl-ether on glycemia and on some variables of intermediate metabolism in rats. Arch Int Physiol Biochem Biophys, 100(5): 335-7.