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Evaluation of Carbonmonoxide, Diffusion Capacity, Respiratory Muscle Strength Values, and Pulmonary Volume in Smoking
Kadir Burak Akgün1, Cengiz Özge1, Bahar Taşdelen2
1Department of Pulmonary Diseases, Mersin University, Faculty of Medicine, Mersin, Turkey.
Objective:
To determine the effects of tobacco use on the lungs before respiratory symptoms or basic functional disorders occur.
Material And Methods:
Forty-six active smokers between June 2018 and June 2019 who did not have any respiratory complaints, had no lung or chronic disease affecting the respiratory system, and consumed at least 20 packs/year were prospectively evaluated. In addition, a control group consisting of 50 non-smokers was formed. After confirming that spirometry and chest radiographs were normal, volunteers were taken to measure carboxymetry, plethysmography, respiratory muscle strength, and diffusion capacity, respectively. The changes in the lungs caused by smoking were analyzed with the data obtained from the measurements.
Results:
Carbon monoxide values measured by carboxymetry were higher in smokers than non-smokers. Plethysmography tests showed that TLC, TLC%, FRC, FRC%, and RV values were statistically higher in smokers. No significant difference was found between FVC%, FEV1%, PEF, PEF%, MEF75, MEF75%, MEF50, MEF50%, MEF25, MEF25%, sRaw (eff), sRaw (eff%), Raw (eff), Raw (eff%), Raw (tot), Raw (tot%), IC, IC%, ERV, ERV%, RV% values and FEV1/FVC, FEV3/FVC, IC/TLC, and RV/TLC ratios. MIP, MIP%, MEP, MEP% values which measured respiratory muscle strength were similar in smokers and non-smokers. DLCO%, DLCO/VA, DLCO/VA%, DLCOc%, DLCOc/VA, and DLCOc/VA% were found to be lower in the smoker subjects. DLCO and DLCOc values were similar in both groups.
Conclusion:
Smoking causes the accumulation of toxic gas in the lungs, contributes to the development of hyperinflation and disrupts gas exchange. In our study, there was no evidence that airway resistance developed or respiratory muscles were affected.
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