Abstract:

Objective The goals of this study were to use a computerized analytic acoustic tool to evaluate respiratory sound patterns in asthmatic patients during acute attacks and after clinical improvement and to compare asthmatic profiles with those of normal individuals.Methods Respiratory sound analysis throughout the respiratory cycle was performed on 22 symptomatic asthma patients at the time of presentation to the emergency department and after clinical improvement. Data of 15 healthy volunteers were analyzed as a control group. Vibrations patterns were plotted. Right and left lungs were analyzed separately. Results Asthmatic attacks were found to be correlated with asynchrony between lungs. In normal subjects, the inspiratory and expiratory vibration energy peaks (VEPs) occurred almost simultaneously in both lungs; the time interval between right and left expiratory VEPs was (0.006±0.012) s. In symptomatic asthmatic patients on admission, the time interval between right and left expiratory VEPs was (0.14±0.09) s and after clinical improvement the interval decreased to (0.04±0.04) s. Compared to healthy volunteers, asynchrony between two lungs was increased in asthmatics (P<0.05). The asynchrony was significantly reduced after clinical improvement (P<0.05). Conclusion Respiratory sound analysis demonstrated significant asynchrony between right and left lungs in asthma exacerbations. The asynchrony is significantly reduced with clinical improvement following treatment.

Key words: asthma, vibration energy peaks, asynchrony of respiratory sounds