Enflurane Structure is a halogenated methyl ethyl ether and is an isomer of isoflurane. Enflurane structure makes it a colourless liquid, noncorrosive to aluminium, iron as well as copper, non-flammable, stable to light and UV light, does not need a chemical stabilizer.
Physical properties: The bp is 56.5°C, The SVP 172 mm Hg (22.9 kPa), blood/gas 1.91 at 37°C. Under certain conditions, may react with soda lime and baralyme to produce CO. It has a MAC of 1.68 in adults, almost double that of halothane; MAC is lower in neonates and old age. Metabolism 2.5%.
Uptake and distribution: Because of lower blood/gas solubility, alveolar equilibration is faster than halothane, however airway irritation limits the rate of induction. Enflurane Structure has like other agents a 5-compartment distribution, viz., the lungs, blood, VRG organs, muscle and peripheral fat.
Metabolism of enflurane structure occurs in the liver cells by P450 (2E1) enzyme. About 2.5% is metabolized; metabolites—organic and inorganic fluorides—are excreted in the urine.
In the presence of enzyme inducing drugs like isoniazid, the fluoride excretion may increase; if above 50 imol it is nephrotoxic. 80—90% of enflurane structure is excreted in exhaled air and a small amount diffuses through the skin.