Spectral Analysis of Abnormal Breath Sounds in Childhood Pneumonia

Auscultation is an important procedure in physical examination. In respiratory diseases such as pneumonia, physician observe the abnormal breath sounds to support the diagnosis. Currently in Indonesia, majority of auscultation uses analog stethoscope. Therefore, the characteristic of the abnormal sounds cannot be analyzed further. In this work, we implemented electronic stethoscope to capture the abnormal breath sounds from pediatric subjects diagnosed as pneumonia. To study the characteristic of the abnormal breath sounds we computed the mathematical feature of formant frequency. We investigated three types of abnormal breath sounds from seven children younger than 5 years diagnosed as pneumonia. The typical abnormal sounds from these subjects were wheezing (31.2%), ronchi (28.5%), and stridor (40.4%). In children younger than 12 months all formant frequency of wheezing versus ronchi and stridor versus ronchi were significantly different (p<;0.05) except in F2. In this group, wheezing and stridor were not significantly different in all formant frequency. In group of children older than 12 months, all formant frequency (F1-F5) of wheezing versus ronchi and wheezing versus stridor were also significantly different (p<;0.05). In contrast, stridor and ronchi only significantly different in F2 and F4. These results are useful for development of smart auscultation system for remote areas as well as telemedicine systems.