Clinical physiology and functional imaging
-
Clin Physiol Funct Imaging · May 2021
Transcutaneous PCO2 -based dead space ventilation at submaximal exercise accurately discriminates healthy controls from patients with chronic obstructive pulmonary disease.
Increased physiological dead space ventilation (VD /VT ) at exercise reflects pulmonary gas exchange impairment and is a sensitive marker of cardio-respiratory disease. VD /VT is typically not measured during routine cardiopulmonary exercise testing (CPET) because its calculation requires arterial blood gas analysis for determination of PaCO2 . Instead, dead space ventilation is indirectly evaluated as a determinant of the ventilation (VE)/VCO2 relationship, which also depends on the PaCO2 set point. We hypothesized that VD /VT calculations based on non-invasive transcutaneous PCO2 (PtcCO2 ) measurement had better diagnostic characteristics than the VE/VCO2 slope for the discrimination of healthy subjects from patients with COPD, a common disease associated with impaired pulmonary gas exchange. ⋯ PtcCO2 -based VD /VT was the most accurate measurement to discriminate healthy controls from subjects with COPD, a chronic lung disease associated with altered pulmonary gas exchange. Non-invasive monitoring of PtcCO2 may be useful for routine CPET.