The Correlation between Lung Sound Distribution and Pulmonary Function in COPD Patients

Abstract

BackgroundRegional lung sound intensity in chronic obstructive pulmonary disease (COPD) patients is influenced by the severity and distribution of emphysema, obstructed peripheral airways, and altered ribcage and diaphragm configurations and movements due to hyperinflation. Changes in the lung sound distribution accompanied by pulmonary function improvements in COPD patients were observed after bronchodilator inhalation. We investigated the association of lung sound distribution with pulmonary functions, and the effects of emphysematous lesions on this association. These studies were designed to acquire the basic knowledge necessary for the application of lung sound analysis in the physiological evaluation of COPD patients.MethodsPulmonary function tests and the percentage of upper- and lower-lung sound intensity (quantitative lung data [QLD]) were evaluated in 47 stable male COPD patients (54 - 82 years of age). In 39 patients, computed tomography taken within 6 months of the study was available and analyzed.ResultsThe ratio of lower QLD to upper QLD showed significant positive correlations with FEV1 %predicted (%FEV1; ρ = 0.45, p<0.005) and MEF50 %predicted (%MEF50; ρ = 0.46, p<0.005). These correlations were not observed in COPD patients with dominant emphysema (% low attenuation area >40%, n = 20) and were stronger in less emphysematous patients (n = 19, %FEV1; ρ = 0.64, p<0.005, %MEF50; ρ = 0.71, p<0.001).ConclusionsIn COPD patients, the ratio of lower- to upper-lung sound intensities decreased according to the severity of obstructive changes, although emphysematous lesions considerably affected lung sound distribution.

Reliability, validity and minimal detectable change of computerized respiratory sounds in patients with chronic obstructive pulmonary disease

“…Significant and lower correlations were also found between FEV 1 %predicted and Imax at the anterior chest. Similar results have been reported and might be related with a shift of regional ventilation from the lower‐ to upper‐lung locations as a function of the degree of hyperinflation presented in more severe COPD patients. This type of hyperinflation can be reversed with therapy and inspiratory maximum intensity recorded at the anterior chest may be an adequate outcome measure to assess these changes.…”

“…Significant and lower correlations were also found between FEV 1 %predicted and Imax at the anterior chest. Similar results have been reported 40 and might be related FIGU RE 1 Bland and Altman plots of number of crackles and wheeze occupation rate (%Wh) collected at session 1 (S1) and session 2 (S2) at posterior right and left chest. Solid lines represent the zero value, and dashed lines show the associated bias and 95% upper limit of agreement (ULA) and lower limit of agreement (LLA) FIGU RE 2 Bland and Altman plots of median frequency (F50) and maximum intensity (Imax) collected at session 1 (S1) and session 2 (S2) at posterior right and left chest.…”

Locating Nidi for High-Frequency Chest Wall Oscillation Smart Therapy via Acoustic Imaging of Lung Airways as a Spatial Network

“…Although positive correlation can be identified through acoustic imaging and lung disorders, chronic respiratory diseases, such as asthma and COPD, have not been correlated positively [5], [22]. Moreover, the correlation between acoustic sensors placement and sensitivity were not investigated, and the position of the sensors was typically empirical [5], [11], [23].…”

Use of Electronic Auscultation in Full Personal Protective Equipment to Detect Ventilation Status in Selective Lung Ventilation: A Randomized Controlled Trial

“…Furthermore, the obstructive lung disease is a common comorbidity among patients undergoing thoracic surgery and accordingly we observed that a considerable number of participants (20%) had obstructive pulmonary disease in the present study. The intensity and distribution of lung sounds are profound altered in patients with obstructive lung disease ( 27 ) and this may hamper correct auscultation. Nevertheles,.…”