[Effects of halogenated hydrocarbons on polarographic measurement of oxygen partial pressure (author's transl)].

Halothane can be reduced polarographically. The presence of halothane in a probe therefore may lead to an erroneous determination of oxygen partial pressure with a greater or less overestimation of the actual oxygen tension. In this study we report extent to which halothane influences the polarographic determination of oxygen tension in blood samples and in the transcutaneous determination of arterial oxygen tension. A clear dependence on halothane concentration was found concerning the transcutaneous measurement of oxygen tension, while measurement of oxygen tension in blood samples by means of the Combianalysator (Fa. Eschweiler, Kiel) was not affected by halothane. The different effect of halothane on the oxygen measurement is apperantly due to the size of the polarizing voltage. Below values of 500 to 600 mV halothane is practically not reduced, whereas above this range reduction takes place which results in an additional polarizing current superimposing the signal of the reduction of oxygen.