支气管激发试验中呼吸音分析的研究

Bronchial Provocation Test Using Computerized Respiratory Sounds Analysis

目的:评价肺音图能否作为支气管激发试验的监测指标。方法:选取肺通气功能正常的缓解期支气管哮喘患者18例、健康对照者6例,进行组胺支气管激发试验;对支气管激发试验用药前、后肺音图参数即肺音强度(LSI)、最大峰值处的频率(PF)、功率谱曲线下面积划成4等份处的频率(Q25、Q50、Q75);进行自身对照研究,并比较支气管哮喘组与健康对照组激发前、后肺音图参数的变异率。结果:支气管哮喘组激发后PF、Q50(分别为186.4±120.5,296.5±210.5,P<0.05和221.1±105.5,332.7±210.2.P<0.02)均有显著性增高。健康对照组组胺激发前、后肺音图参数均无明显差异(P<0.05)。支气管哮喘组与健康对照组激发前、后肺音图参数的变异率△PF％、△Q50%在吸气相两组差异有显著性。结论:肺音图参数能灵敏地反映气道炎症所致的气道形态改变对呼吸音的产生与传导的影响,是敏感、有效的支气管激发试验监测指标。

Objective: To determine whether spectral analysis of respiratory sounds-phonopneumography is a sensitive and valid method for bronchial provocation testing. Methods: We measured FEV1and recording the airflow standardized respiratory sounds at the trachea before and after Rx respectively in 18 mild asthmatics and 6 healthy controls. Power spectra were analyzed for lung sound intensity (LSI), the frequency of the maximal power spectrum (PF), and quartile power points (Q25,Q50,Q75). These sound characteristics were studied in absence (Base) and presence (Rx) of the challenge. The lung sound variability was determined for comparison between asthmatics and healthy subjects. Results: In asthmatics, PF and Q50 were both elevated during airway obstruction (P < 0. 05 and P < 0. 02, respectively). Of all the lung sound variables measured, the PF and Q50 of inspiratory sounds were significantly larger in asthmatics than in healthy subjects (P < 0. 05). Conclusion: These data suggest that the airflow-standardized phonopneumography is a sensitive method for detecting differences between asthmatics and healthy subjects and that it can be applied to patients with limited cooperation during bronchial challenge test.