Long-Term Auscultation in Chronic Obstructive Pulmonary Disease: Renaissance of an Ideograph of Medical Care

Abstract

<b><i>Background:</i></b> Electronic auscultation technology has advanced dramatically in the last few years. Therefore, long-term pulmonary auscultation could provide additional information about respiratory system by monitoring acute chronic obstructive pulmonary disease (AECOPD) exacerbations or by identifying wheezing phenotypes amongst stable COPD patients. <b><i>Objectives:</i></b> Comparison of respiratory sounds in stable versus AECOPD patients recorded with a portable respiratory sound monitor over a period of 24 h. <b><i>Methods:</i></b> This prospective trial evaluated cough and wheezing events using an auscultation monitor specially developed for this purpose with 4 integrated highly sensitive microphones, in stable and severely AECOPD patients for a period of 24 h in an inpatient setting. <b><i>Results:</i></b> Twenty stable COPD patients (12 male, 60%) and 20 severely exacerbated COPD patients (14 male, 70%) were analyzed. In AECOPD patients, long-term auscultation revealed a significantly higher number of wheezing epochs than stable COPD patients (591 [IQR: 145–1,645] vs. 152 [IQR: 90–400]; <i>p</i> = 0.021). Conversely, cough epochs did not differ between AECOPD and stable COPD patients (213 [IQR: 140–327] vs. 162 [IQR: 123–243]; <i>p</i> = 0.256). The Borg-dyspnea scale, CAT score, and total CCQ score each showed no correlation with wheezing frequency, while CAT and CCQ scores did correlate with coughing frequency. <b><i>Conclusion:</i></b> Wheezing, but not coughing, occurs more frequently in AECOPD patients than in stable COPD patients, indicating that severe wheezing is an important clinical sign of exacerbation, while coughing is not. Therefore, the patterns of wheezing and coughing, as assessed by long-term auscultation, differ in stable versus exacerbated COPD patients.