A new implementation of EN1839 method T mixture preparation to prepare calibration gas mixtures for anesthetic gas monitors

In this study different mixtures from anesthetic liquids vapours in air and O₂—sevoflurane/air, sevoflurane/O₂ and isoflurane/O₂—were prepared according to EN1839 method T. The gases mixtures were used to calibrate anesthetic gas monitors. The targeted concentrations (TCs) from sevoflurane and isoflurane in air and O₂ were 0 vol%, 0.15 vol%, 0.7 vol%, 1 vol%, 1.5 vol%, 2.5 vol%, 5 vol%, 6 vol% and 8 vol%. The values of liquids, air and O₂ flow rates which are corresponding theoretically to the TCs were calculated. The results showed that the measured concentrations by anesthetic gas monitor are in good agreement with TCs. Full validation was performed to assure the suitability of the method for preparing gas mixtures to calibrate anesthetic gas monitors. Linearity, limit of detection (LOD), limit of quantification (LOQ), precision, method robustness and uncertainty of measurement results were evaluated in the validation study. The results indicated that the method is valid for the purpose of analysis.