Errors in oxygen tension measurements caused by halothane.
Halothane, independent of oxygen tension, increased the signal of the gold/silver-silver chloride microelectrode. The output of microelectrodes at different oxygen tensions in the presence of increasing amounts of halothane has been measured. Halothane causes an increase in the electrode signal which is proportional to its concentration. This effect results from the polarographic reduction of halothane. It is concluded that the gold/silver-silver chloride microelectrode cannot be used to measure oxygen tension during halothane anaesthesia.
The gas chromatographic estimation of halothane in blood using electron capture detector unit.
A method for quantitative estimation of low concentrations of halothane in blood by gas chromatography and electron capture detection has been described. The mean recovery of halothane from blood in the range of 7.10–26.12 mg/100 ml was 96.98% (SD 227). The mean of the standard deviations of duplicate extractions was 0.87. With low blood halothane concentrations 112.54–323.00 / * μg/100 ml, the mean per cent recovery was 107.41% (SD 5.18) and the mean of the standard deviations of duplicate extractions was 2.89.
GAS CHROMATOGRAPHY FOR RESPIRATORY AND BLOOD GAS ANALYSIS *
Gas chromatography is a relatively new technique that can be used for the analysis of a wide variety of materials. Sufficient progress has been made in chromatographic techniques within the last few years so that the method can provide the sensitivity and accuracy required for analysis of gas mixtures important in medicine and physiology. This report is concerned primarily with the technique for measuring oxygen and carbon dioxide in respiratory gas and blood samples, but the technique has been applied to other gases equally important in clinical and research f ie ld~. l -~