DETERMINATION OF ANESTHETIC AGENT CONCENTRATION BY REFRACTOMETRY

Reference refractivity values have been derived for the anaesthetic ag ents halothane, isoflurane, enflurane, sevoflurane and desflurane whic h are traceable to national measurement standards. A simple method and equation have been derived for the application of these data to the m easurement of agent concentration by refractometry. The main instrumen tal sources of uncertainty associated with this method are discussed a nd their respective contributions quantified. Agent concentration can be measured routinely at the +/-1% level of uncertainty using this app roach.