[Comparative measurement of oxygen uptake and cardiac output at rest and during stress--evaluation of a new monitor for continuous determination of oxygen uptake and carbon dioxide release].

A new device for the continuous monitoring of oxygen uptake and carbon dioxide delivery is presented, which is based on a continuous expired gas analysis using a paramagnetic oxygen and an infrared-absorption carbon dioxide sensor. To validate the results, data of measured oxygen uptake and cardiac output calculated by the Fick principle were compared to synchronous thermodilution measurements at rest and during exercise. Measurements were performed at rest on 18 patients, additionally 13 of the patients were exercised with either 25 W or 50 W workload. The results indicate, for both measurement series, a significant correlation (r greater than 0.95, p less than 0.001) and exemplify that the measurement of oxygen uptake by expired gas analysis permits a precise analysis of the cardiovascular transport function during exercise.