1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, Guangdong, China.
Ann Am Thorac Soc. 2015 May;12(5):657-65. doi: 10.1513/AnnalsATS.201406-280OC.
The usefulness of impulse oscillometry (IOS) in bronchiectasis has not been systematically investigated.
To determine the usefulness of IOS parameters and their correlation with radiology, disease severity, sputum bacteriology, and spirometry, and to compare the changes in IOS parameters during exacerbations and convalescence of bronchiectasis.
We recruited 100 patients with bronchiectasis and 28 healthy subjects. Receiver operating characteristic curve was plotted to analyze the diagnostic performance of IOS parameters. Chest high-resolution computed tomography (HRCT), Bronchiectasis Severity Index (BSI) assessment, sputum culture, and spirometry were performed. Correlation between IOS parameters and clinical indices was determined using the Spearman model. Changes in IOS parameters, compared with spirometry, during exacerbation were assessed in 16 patients with bronchiectasis.
IOS parameters (in particular, resonant frequency) could discriminate patients with bronchiectasis from healthy subjects. Higher levels of IOS parameters were associated with Pseudomonas aeruginosa infection, dyshomogeneity, higher BSI and HRCT score, more bronchiectatic lobes, and cystic bronchiectasis (all P < 0.05). All IOS parameters but lung resistance at 5 Hz were positively correlated with the duration of bronchiectasis symptoms, number of bronchiectatic lobes, HRCT total scores, and BSI (all P < 0.05), but not sputum bacterial density (P > 0.05). IOS parameters, but not spirometric parameters, were not statistically different between peripheral and peripheral plus central segment bronchiectasis (all P > 0.05). Increased frequency dependence (higher resonance frequency or reactance area) was more likely to be associated with lower HRCT scores (≤5) than FEV1. Compared with FEV1, any single IOS parameter being abnormal was more common in mild bronchiectasis, particularly in patients with HRCT score of 5 or lower. IOS parameters were not statistically different from baseline to exacerbations and convalescence (all P > 0.05).
IOS parameters correlate with clinical indices and could reflect peripheral airway abnormality. An increased number of aberrant IOS parameters signals poorer clinical conditions. Increased frequency dependence might be a sensitive marker of mild bronchiectasis. Any single IOS parameter being abnormal sensitively reflects mild bronchiectasis. IOS parameters do not change significantly during bronchiectasis exacerbations. Clinical Trial registered with www.clinicaltrials.gov (NCT01761214).
脉冲振荡法（IOS）在支气管扩张症中的应用尚未得到系统研究。
确定 IOS 参数的有用性及其与影像学、疾病严重程度、痰细菌学和肺功能的相关性，并比较支气管扩张症加重期和恢复期 IOS 参数的变化。
我们招募了 100 例支气管扩张症患者和 28 例健康对照者。绘制受试者工作特征曲线以分析 IOS 参数的诊断性能。进行胸部高分辨率计算机断层扫描（HRCT）、支气管扩张严重程度指数（BSI）评估、痰培养和肺功能检查。采用 Spearman 模型确定 IOS 参数与临床指标的相关性。在 16 例支气管扩张症患者中评估 IOS 参数与肺功能相比在加重期的变化。
IOS 参数（特别是共振频率）可区分支气管扩张症患者和健康对照者。更高的 IOS 参数水平与铜绿假单胞菌感染、异质性、更高的 BSI 和 HRCT 评分、更多的支气管扩张肺叶和囊状支气管扩张（均 P<0.05）相关。所有 IOS 参数（除了 5Hz 时的肺阻力）均与支气管扩张症状持续时间、支气管扩张肺叶数、HRCT 总分和 BSI 呈正相关（均 P<0.05），但与痰细菌密度无关（P>0.05）。IOS 参数，而不是肺功能参数，在周围型和外周加中央段支气管扩张症之间没有统计学差异（均 P>0.05）。与 FEV1 相比，频率依赖性增加（更高的共振频率或电抗面积）更可能与较低的 HRCT 评分（≤5）相关。与 FEV1 相比，任何单个 IOS 参数异常在轻度支气管扩张症中更为常见，尤其是在 HRCT 评分≤5 的患者中。IOS 参数在加重期和恢复期与基线相比没有统计学差异（均 P>0.05）。
IOS 参数与临床指标相关，可反映外周气道异常。异常 IOS 参数数量的增加表明临床状况较差。频率依赖性增加可能是轻度支气管扩张症的敏感标志物。任何单个 IOS 参数异常都能灵敏地反映轻度支气管扩张症。IOS 参数在支气管扩张症加重期没有明显变化。临床试验在 www.clinicaltrials.gov 注册（NCT01761214）。
