[D-glucaric acid. A new method proposed to investigate damage from exposure to anesthetic gas and vapors].

Acute exposure and hepatotoxicity following full anesthetic doses is controversial, despite various experimental trials. On the other hand, microsomial enzyme induction following the chronic use of anesthetic gases and vapours, even with minimal metabolism, has been established. Therefore, there is increasing interest in the field of prevention to develop techniques and instruments to minimize pollution of anesthetic vapours and screening methods to detect early liver-damage. We have evaluated the reliability of D-Glucaric Acid test in monitoring microsomial enzyme induction after anesthesia. We evaluated urinary excretion of D-Glucaric Acid before and after exposure to anesthetic gases in 53 subjects, including medical personnel and patients. Statistical analysis of these data confirm the usefulness of this technique to assess acute liver damage in patients undergoing general anesthesia (postoperative increase of 10.5 microns/l as average value of urinary acid excretion, chi 2 = 9.8; p less than 0.01). This technique is also valuable in demonstrating damage in operating room personnel due to chronic exposure (base values greater than 12 microns/l in anesthesiologists with a 9 microns/l increase at the end of surgical intervention, chi 2 = 8.1; p less than 0.01). Data of patients submitted to local anesthesia are more difficult to interprete. They presented a decrease in acid urinary excretion (less than 10 microns/l; chi 2 = 1.93; p less than 0.2) probably due to hemodynamic changes which occurred during spinal block or due to degree of sedation related to de-afferentation itself.