A new device for continuous measurement of gas exchange during artificial ventilation

A new apparatus, which uses a fuel cell for measuring O2 concentration and calculates O2 consumption (VO2), has been developed for use on the Servo Ventilator. Together with an IR CO2 Analyzer, this equipment also provides CO2 production, end-tidal CO2 concentration, and the respiratory quotient.l The accuracy of this equipment was evaluated by comparison with results from two standard methods: the Scholander technique in combination with a dry gas meter, and mass spectrometry combined with a wet gas meter. The results show that the differences between the VO2 calculated from this equipment and two other standard methods are less than 5%. Thus, the accuracy of the new equipment seems reliable enough to make it a valuable tool in clinical use.