The optimal design for cylindrical tubes used as acoustic stethoscopes for auscultation in COVID-19 diagnosis

TL;DR

This paper proposes an optimal design for a simple cylindrical tube stethoscope, based on acoustic waveguide theory, to improve auscultation during COVID-19, considering geometric parameters, surface treatments, and noise reduction.

Contribution

It introduces a theoretically grounded design framework for a cylindrical stethoscope tailored for COVID-19 auscultation, optimizing acoustic performance and usability.

Findings

Guidelines for geometric parameter selection based on acoustic theory

Recommendations for inner wall surface treatments

Suggestions for noise reduction methods

Abstract

During the COVID-19 outbreak, the auscultation of heart and lung sounds has played an important role in the comprehensive diagnosis and real-time monitoring of confirmed cases. With clinicians wearing protective clothing in isolation wards, a potato chip tube stethoscope, which is a secure and flexible substitute for a conventional stethoscope, has been used in the first-line treatment of COVID-19 by Chinese medical workers. In this study, an optimal design for this simple cylindrical stethoscope is proposed based on the fundamental theory of acoustic waveguides. Analyses of the cut-off frequency, sound power transmission coefficient, and sound wave propagation in the uniform lossless tube provide theoretical guidance for selecting the geometric parameters for this simple cylindrical stethoscope. In addition, relevant suggestions about surface treatments for the inner wall as well as the use of noise-reduction earplugs are also part of this optimal design.