TOXICOLOGY AND CLINICAL-SIGNIFICANCE OF B ASE-CATALYZED DEGRADATION OF SEVOFLURANE TO COMPOUND-A

Sevoflurane breaks down in basic environments to form a vinyl ether kn own as Compound A. This compound is toxic in the rat, with an LC(50) o f about 400 ppm after 3 h exposure and with renal damage evident betwe en 50 and 100 ppm. There is no valid current evidence that Compound A is toxic in man, and the rat may not be an appropriate model for deter mination of this breakdown product's toxic potential in humans. The ma in factors influencing the degree of patient exposure to Compound A in clude fresh gas flow, sevoflurane concentrations; absorber temperature and composition, and the patient's carbon dioxide production.