The halogenated anesthetics, halothane, enflurane and isoflurane undergo biotransformation in man. They produce inorganic fluoride ion as a metabolite, which is well known as the cause of methoxyflurane induced nephrotoxicity. This study was done
to
investigate the rapidity and extent of biotransformation of volatile anesthetics for 2 hours of operation.
Thirty patients were randomly divided into halothane, enflurane and isoflurane group according to anesthetics. Blood and urine sampling was done before operation, post-induction 10 min, 20 min, 30 min, 1 hour, 1 hour 30 min and 2 hours for the
measurement of inorganic fluoride ion. Aspartate aminotransferase, alanine aminotransferase, blood urea nrea nitrogen and creatinine levels were measured before and 24 hours after operation.
@ES The results were as follows:
@EN 1) The values of blood fluoride ion in halothane and isoflurane group were decreased with time during operation and there was no change in enflurane group.
2) The values of urine fluoride ion in three groups were increased with time during operation. The rate of increase was the greatest in enflurane group.
3) There were no changes in the value of AST, ALT, BUN and creatinine.
The above results suggest that the biotransformation of volatile anesthetics to inorganic fluoride ion was the greatest in enflurane, but the level was insufficent to cause renal dysfunction during 3.18 hour operation.
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