RT Journal Article
SR Electronic
T1 Evaluating Endogenous Carbon Monoxide (CO) Production as an Indicator for Pulmonary Function Testing (PFT)
JF Respiratory Care
FD American Association for Respiratory Care
SP 3407806
VO 65
IS Suppl 10
A1 Jung Eun Kim
YR 2020
UL http://rc.rcjournal.com/content/65/Suppl_10/3407806.abstract
AB Background: Chronic lung diseases, such as COPD and asthma, are associated with considerable morbidity and mortality and involve chronic inflammation and oxidative stress. However, the diseases are not diagnosed and treated efficiently in routine clinical practice because of the difficulties in monitoring inflammation. Consequently, it is often too late to alter respiratory dysfunction when patients’ referral for pulmonary function testing is delayed. The purpose of this study was to explore the possible associations between pulmonary function test (PFT) measurements and exhaled carbon monoxide (eCO) levels as an indicator of generalized inflammation. Data analysis was conducted to determine a potential level of eCO to use as an indicator for conducting PFT. Methods: A sample of 343 subjects, who were referred by their physicians for a routine care PFT, were recruited from the Queen’s Medical Center Pulmonary Lab in Honolulu, Hawaii. A study-specific information sheet was provided to the subjects as part of the informed consent process, and the subjects’ data were collected through a Demographic Data Questionnaire. Exhaled carbon monoxide (eCO) levels were measured with a portable carbon monoxide analyzer (MicroCO Meter), and the maximum values from three successive measurements were used in all calculations. Results: FVC, FEV1, FEV1/FVC, and FEF25-75% decreased with elevated concentrations of eCO. In females, decreased lung volumes (TLC, FRC, and RV) were associated with increased eCO levels. In males, increased lung volumes were associated with increased eCO levels. Diffusion capacity of lungs for carbon monoxide (DLCO) and eCO levels also showed the opposite correlation between females and males. DLCO of female subjects markedly decreased with increased levels of eCO while DLCO of male subjects mildly increased. Appropriate cut-off points of eCO levels also were examined to determine the most efficient use of eCO as an indicator for PFT. The present study found that a cut-off point for eCO of 6 ppm provided the best relationship between sensitivity and specificity in predicting the need for PFT. Conclusions: eCO measurement, which is noninvasive, quick, inexpensive, and easily administered by primary care physicians, could serve as a useful biomarker for monitoring patients with pulmonary diseases. Therefore, eCO measurement may be clinically useful as a diagnostic tool to identify inflammation and to serve as an indicator of the need to conduct PFT. Exhaled CO Levels and PFT Results of Female ParticipantsExhaled CO Levels and PFT Results of Male Participants