Related Experiment Video
Updated: May 8, 2026
Evaluation of Capnography Sampling Line Compatibility and Accuracy when Used with a Portable Capnography Monitor
Published on: September 29, 2020
Bench test assessment of mainstream capnography during high frequency oscillatory ventilation
Caroline M Hartdorff1, Marc van Heerde, Dick G Markhorst
1Pediatric Intensive Care Unit, VU University Medical Center, PO BOX 7057, 1007 MB, Amsterdam, The Netherlands.
Abstract:
To assess the feasibility, stability and predictability of pCO2 measurement (PETCO2) using a main stream capnograph in a high frequency oscillatory ventilation circuit. A commercially available capnograph was mounted into a high frequency oscillatory ventilator patient circuit, adjustable CO2 flow was introduced into an artificial lung and the output of the CO2 sensor assessed under varying ventilator settings. Influence of oxygen content, pressures, heat and moisture were recorded. A linear relationship between CO2 flow rate and PETCO2 was found. Varying ventilator settings influenced the measurements, but the results for PETCO2 remained within a range of 1.5 mmHg above or under then mean measurement value. Measurements remained stable despite humidification, heat, pressure amplitudes or mean airway pressure changes. From this bench test, we conclude it is feasible to measure PETCO2 using a main stream capnograph during high frequency oscillatory conditions, these measurements were stable during the experiment. Changes in CO2 production or output can be detected. The system may prove to be of clinical value, but further in vivo measurements are warranted.
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