Simultaneous determination of fluorinated inhalation anesthetics in blood by gas chromatography-mass spectrometry combined with a headspace autosampler

Although the fluorinated inhalation anesthetics, including desflurane, sevo flurane, isoflurane, enflurane, and halothane are commonly used, fatal case s resulting from their abuse or misuse have been reported. To date, gas chr omatography (GC) equipped with different kinds of detectors has been utiliz ed to analyze inhalation anesthetics. However, none of them can detect desf lurane reliably or analyze all five common anesthetics simultaneously. The purpose of the present work is to further modify the previously developed h eadspace (HS) GC-MS method for blood isoflurane determination to analyze an d distinguish five common clinical inhalation anesthetics, simultaneously. The modified HS-GC-MS method adopts a 60 mx0.25 mm I.D., 0.25 mum film thic kness DB-5 capillary column along with an adequate GC temperature program, which gives the five inhalation anesthetics, including isoflurane and its i somer, enflurane, a high resolution. The method also takes both the volatil ity and the influence of the top space on the obtained concentration into c onsideration and therefore keeps the sample loss acceptable even for analyz ing the highly volatile desflurane. Within a certain concentration range of the calibration standard (about 20-300 mug/ml), this method shows a good l inearity with correlation coefficients greater than 0.999. In addition, bot h within- and between-run precision and accuracy results meet the validatio n requirements as well as the tested results of practical blood samples of desflurane. In summary, this is a reliable analytical method to simultaneou sly determine the concentration of five common inhalation anesthetics in bl ood. Such a method is very practical for both clinical and occupational mon itoring, as well as for analytical toxicology. (C) 2001 Elsevier Science B. V. All rights reserved.