Monitoring of blood pO/sub 2/ with a thin film amperometric sensor

Abstract
A sample-taking sensor system for online pO/sub 2/ monitoring of blood is described. The system consists of a two-lumen catheter with a thin-film amperometric sensor cell, a pump unit with instrumentation, and a personal computer. The planar three-electrode system is only covered by a hydrophilic pHEMA membrane to avoid alterations in the composition of any internal electrolyte solution. To overcome the problem of electrode poisoning, the surface of the working electrode is regenerated during the calibration mode of the calibration/measurement cycle. Animal studies have been performed with anaesthetized pigs. The comparison of the sensor values with blood gas analyzer data shows a curved but reproducible correlation.