title: Determination of anaesthetic agent concentration by refractometry.
abstract: Reference refractivity values have been derived for the anaesthetic agents halothane, isoflurane, enflurane, sevoflurane and desflurane which are traceable to national measurement standards. A simple method and equation have been derived for the application of these data to the measurement of agent concentration by refractometry. The main instrumental sources of uncertainty associated with this method are discussed and their respective contributions quantified. Agent concentration can be measured routinely at the +/- 1% level of uncertainty using this approach.
authors.affiliation: Division of Mechanical and Optical Metrology, National Physical Laboratory, Teddington, Middlesex.
authors.forename: J M
authors.initials: JM
authors.lastname: Allison
authors.forename: R S
authors.initials: RS
authors.lastname: Gregory
authors.forename: K P
authors.initials: KP
authors.lastname: Birch
authors.forename: J G
authors.initials: JG
authors.lastname: Crowder
mesh_terms: D018685:Anesthetics, Inhalation / Q000032:analysis*; D000077335:Desflurane; D004737:Enflurane / Q000032:analysis; D004987:Ethers / Q000032:analysis; D006221:Halothane / Q000032:analysis; D007530:Isoflurane / Q000031:analogs & derivatives / Q000032:analysis; D008738:Methyl Ethers; D012016:Reference Values; D012031:Refractometry; D012680:Sensitivity and Specificity; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D004987:Ethers; D008738:Methyl Ethers; D000077149:Sevoflurane; D004737:Enflurane; D000077335:Desflurane; D007530:Isoflurane; D006221:Halothane