Goldman Michael D, Nazeran Homer, Ramos Carlos, Toon Emily, Oates Katrina, Bilton Diana, Meraz Erika, Hafezi Nazila, Diong Bill
University of Texas at El Paso, TX 79968, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2010;2010:2467-72. doi: 10.1109/IEMBS.2010.5626611.
The use of the forced oscillatory input impedance parameter, frequency-dependence of Resistance (fdR), to assess small airway impairment (SAI) has not been widely accepted due to concern about the effects of "upper airway shunt" on oscillometric resistance and low frequency reactance. On the other hand, recent medical studies suggest that low frequency reactance is a very sensitive index of treatment intervention directed at small airways. The present study was undertaken to analyze and compare Impulse Oscillometry (IOS) resistance and reactance data with model-derived indices of small airway function from two models of the respiratory impedance, one with, and the other without an element for upper airway shunt capacitance. Fifty six patients with stable chronic obstructive lung disease of varying severity due to Cystic Fibrosis (CF) and 21 patients with asthma were evaluated by IOS testing. IOS data were input into the augmented RIC (aRIC) model with an upper airway shunt capacitance, and the extended RIC (eRIC) model, without a shunt capacitance element. Model-derived indices were compared between the two models for CF patients separately from asthma patients. We conclude that IOS indices of SAI are modeled equally well with or without upper airway shunt capacitance, and do not seem to be dependent on upper airway shunt capacitance.
由于担心“上气道分流”对振荡阻力和低频电抗的影响，使用强迫振荡输入阻抗参数——电阻频率依赖性（fdR）来评估小气道功能障碍（SAI）尚未被广泛接受。另一方面，最近的医学研究表明，低频电抗是针对小气道的治疗干预的非常敏感的指标。本研究旨在分析和比较脉冲振荡法（IOS）的阻力和电抗数据与来自两种呼吸阻抗模型的小气道功能模型衍生指标，一种模型有上气道分流电容元件，另一种没有。通过IOS测试评估了56例因囊性纤维化（CF）导致的不同严重程度的稳定慢性阻塞性肺疾病患者和21例哮喘患者。将IOS数据输入具有上气道分流电容的增强RIC（aRIC）模型和没有分流电容元件的扩展RIC（eRIC）模型。分别比较了CF患者和哮喘患者在两种模型之间的模型衍生指标。我们得出结论，有无上气道分流电容时，SAI的IOS指标建模效果相同，且似乎不依赖于上气道分流电容。
