Transcutaneous carbon dioxide threshold during exercise.

P Abraham; D Carter; S Bickert; B Desvaux; J L Saumet

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PubMed · 10399415

Transcutaneous carbon dioxide threshold during exercise.

P Abraham·D Carter·S Bickert·B Desvaux·J L Saumet

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Abstract

BACKGROUND: To study the possible use of transcutaneous carbon dioxide pressure measurements to estimate ventilatory threshold during exercise. METHODS EXPERIMENTAL DESIGN: comparative study. SETTINGS: Institutional practice, ambulatory care. Patients and measures: seventy-nine subjects. INTERVENTION: incremental exercise tests with simultaneous recordings of breath by breath gas exchange and transcutaneous carbon dioxide pressure. MEASURES: Six reviewers determined the ventilatory threshold using both the graphs for the carbon dioxide excretion to oxygen consumption relationship: V slope technique (VTa), and the ventilatory equivalent for oxygen uptake changes over time: (VTb), the respiratory compensation point (RCP) on ventilatory equivalent for carbon dioxide, and the transcutaneous threshold (Ttc) on the transcutaneous carbon dioxide pressure changes over time respectively. RESULTS: A Ttc could be defined by all observers in 85% of the subjects. Correlation between Ttc and VT expressed as oxygen consumption absolute values ranged from 0.971 to 0.975 on the mean values of six observers. Using the Bland-Altmann approach, differences (mean +/- SD) were 13 +/- 215, -40 +/- 204, 231 +/- 221 ml.min-1 between Ttc and VTa, RCP respectively. A difference of 38 +/- 173 ml.min-1 was found between VTa and VTb. This suggests that Ttc shows little difference with VT but not with RCP. CONCLUSIONS: We suggest that a carbon dioxide transcutaneous threshold can be found close to the ventilatory threshold. Potential clinical use of transcutaneous device are vast.

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Adolescent Adult Anaerobic Threshold Blood Gas Monitoring, Transcutaneous Carbon Dioxide Exercise Exercise Test Humans Least-Squares Analysis Oxygen Consumption Pulmonary Gas Exchange Comparative Study Journal Article

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P Abraham, D Carter, S Bickert, B Desvaux, J L Saumet. 1999. Transcutaneous carbon dioxide threshold during exercise.. https://pubmed.ncbi.nlm.nih.gov/10399415/

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