A new metabolic simulator system for routine cardiopulmonary exercise test equipment: technical specifications and...

Modern stress-test instruments require non-steady-state calibration (i.e., during exercise) instead of calibration at rest (i.e., before use) in stable conditions. The purpose of the present study was to describe a new specific computer-controlled check system for stress-test instruments, which operates on the basis of physiological respiratory equations. It can produce rapid and automatic modifications of metabolic data, allowing breath-to-breath simulation. When connected to the stress-test equipment to be controlled, it makes it possible to identify discrepancies between preset and measured values. Systematic comparative measurements were performed using as reference two mass spectrometer-controlled analysers and a high-precision flow meter. Accuracy, trend and reproducibility in continuously changing conditions were very satisfactory.