PRECISE DETERMINATION OF REFRACTOMETRIC PARAMETERS FOR ANESTHETIC AGENT VAPORS

The absolute refractive indices of the anesthetic agent vapors isoflur ane, sevoflurane, enflurane, halothane, and desflurane are determined to a typical uncertainty of 1 part in 10(7) over the respective temper ature and pressure ranges of 15-40-degrees-C and 5-45% of their satura ted vapor pressures at wavelengths of 632.99, 594.10, and 543.52 nm. T he specific refraction, second virial coefficients, and dispersion con stants are also derived for each agent, from which an equation for the calculation of agent refractivity is established that is in agreement with the measured data to within 2 x 10(-8).