Study of respiratory function of the lungs in smokers and patients with chronic obstructive pulmonary disease

The article discusses the use of methods for assessing lung respiratory function in patients with chronic obstructive pulmonary disease (COPD) and smokers.

The aim of the study is a comparative evaluation of the informative value of capnometry, spirometry, multiple breath nitrogen washout method, and diffusion test in patients with COPD, as well as an early detection of respiratory function impairment in smokers.

Results. Three groups of patients were examined: 1st — 30 patients with moderately severe COPD, average age 50.6 ± 4.3 years, 2nd — 30 smokers, average age 45.6 ± 2.4 years, 3rd (control group) — 30 practically healthy non-smokers, average age 45.6 ± 2.4 years. Capnometry showed a statistically significant increase in the slope of the alveolar phase in patients with COPD compared to the control group and smokers at rest, both before and after bronchodilator use. Significant differences between smokers and control groups were detected during forced exhalation. According to spirometry data, the FEV1/FVC ratio in patients with COPD was statistically significantly lower compared to the control group and smokers, both before and after bronchodilator use. Diffusion capacity was significantly lower in patients with COPD and smokers compared to the control group. The lung clearance index was significantly higher in the COPD group compared to the other two groups.

Conclusions. All the mentioned methods were informative in patients with COPD, but capnometry and lung diffusion capacity assessment were sensitive methods in smokers, revealing uneven distribution of ventilation-perfusion ratios in the lungs and impaired gas exchange function.

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