| Autor: |
Javiel Ng Jun Wen, Shanshan Lin, Favian Ng Chuan Fang, Hamsan Muthayya, Ravichandran Subbaraman, Shirlynn Ng Wan Ern, Then Tze Kang |
| Rok vydání: |
2014 |
| Předmět: |
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| Zdroj: |
IFMBE Proceedings ISBN: 9783319029122 |
| DOI: |
10.1007/978-3-319-02913-9_208 |
| Popis: |
This paper discusses the design and development of pneumatic wheeze generator that has been developed for the first time to provide wheeze signal for calibrating biomedical tools for analyzing wheeze without the participation of patients. The wheeze generator essentially consisted of vibrating columns which are energized by an airway generator providing inspiratory and expiratory flow patterns. These vibrating columns have been designed to customize the frequency and the pitch of the tones. Wheezes are usually defined as high-pitched continuous tones with a dominant frequency of 400Hz or more. In some patients, they may be audible at some distance from the patient. The transmission of wheezing sounds through airways is better than transmission through the lung to the surface of the chest wall. The higher frequency sounds are more clearly detected over the trachea than at the chest. The high frequency components of breath sounds are absorbed mainly by the lung parenchyma. The peaks at 480 and 650Hz were seen over both locations, but their relative magnitudes were reversed as a result of the low-pass filtering effect of the lung. Wheezing may result from localized or diffused airway narrowing or obstruction from the level of the larynx to the small bronchi. The airway narrowing may be caused by bronchoconstriction, mucosal edema, external compression, or partial obstruction or by tenacious secretions. The mechanisms underlying wheeze production appear to involve an interaction between the airway wall and the gas moving through the airway. Their mechanisms of production have been compared with musical wind instruments. To conclude, the newly developed pneumatic wheeze generator has expanded the scope to perform simulated conditions to fine tune analytical packages for greater accuracies. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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