Methods Inf Med 2013; 52(03): 266-276
DOI: 10.3414/ME12-01-0037
Original Articles
Schattauer GmbH

Linear and Nonlinear Analysis of Base Lung Sound in Extrinsic Allergic Alveolitis Patients in Comparison to Healthy Subjects

S. Charleston-Villalobos
2   Electrical Engineering Department, Universidad Autonoma Metropolitana, Mexico City, Mexico
,
L. Albuerne-Sanchez
2   Electrical Engineering Department, Universidad Autonoma Metropolitana, Mexico City, Mexico
,
R. Gonzalez-Camarena
1   Health Science Department, Universidad Autonoma Metropolitana, Mexico City, Mexico
,
M. Mejia-Avila
3   National Institute of Respiratory Diseases, Mexico City, Mexico
,
G Carrillo-Rodriguez
3   National Institute of Respiratory Diseases, Mexico City, Mexico
,
T. Aljama-Corrales
2   Electrical Engineering Department, Universidad Autonoma Metropolitana, Mexico City, Mexico
› Author Affiliations
Further Information

Publication History

received: 27 April 2012

accepted: 02 April 2012

Publication Date:
20 January 2018 (online)

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Summary

Objective: Pulmonary disorders are frequently characterized by the presence of adventitious sounds added to the breathing or base lung sound (BLS). The aim of this work was to assess the features of BLS in extrinsic allergic alveolitis (EAA) patients in comparison to healthy subjects, applying linear and nonlinear analysis techniques.

Methods: We investigated the multichannel lung sounds on the posterior chest of 16 females, 8 healthy and 8 EAA patients, when breathing at 1.5 L/s. BLS linear features were obtained from the power spectral density (PSD) while nonlinear features were extracted by the concepts of irregularity and complexity, i.e., spectral, sample and multi-scale entropy.

Results: The results demonstrated that spectral percentiles of BLS were lower in EAA patients than in healthy subjects but statistical significance (p<0.05) was obtained only for expiration at the left apical and both basal regions. Also, the maximum amplitude of the PSD in patients reached statistical significance ( p < 0.05) for the expiratory phase at basal regions. In the case of nonlinear techniques, significant lower values ( p < 0.05) were obtained for EAA patients during both respiratory phases at left apical and both basal regions.

Conclusion: In conclusion, we found that BLS in chronic EAA patients is characterized by lower spectral percentiles, lower irregularity and lower complexity than in healthy subjects suggesting the feasibility of its clinical usefulness by screening its temporal alteration.