Biomedical Instrumentation Laboratory, Institute of Biology and Faculty of Engineering, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
Pulmonary Function Laboratory, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
Int J Chron Obstruct Pulmon Dis. 2022 May 4;17:1017-1030. doi: 10.2147/COPD.S353912. eCollection 2022.
Respiratory oscillometry has emerged as a powerful method for detecting respiratory abnormalities in COPD. However, this method has not been widely introduced into clinical practice. This limitation arises, at least in part, because the clinical meaning of the oscillometric parameters is not clear. In this paper, we evaluated the association of oscillometry with functional capacity and its ability to predict abnormal functional capacity in COPD.
This cross-sectional study investigated a control group formed by 30 healthy subjects and 30 outpatients with COPD. The subjects were classified by the Glittre‑ADL test and handgrip strength according to the functional capacity.
This study has shown initially that subjects with abnormal functional capacity had a higher value for resistance (p < 0.05), reactance area (Ax, p < 0.01), impedance modulus (Z4, p < 0.05), and reduced dynamic compliance (Cdyn, p < 0.05) when compared with subjects with normal functional capacity. This resulted in significant and consistent correlations among resistive oscillometric parameters (R=-0.43), Cdyn (R=-0.40), Ax (R = 0.42), and Z4 (R = 0.41) with exercise performance. Additionally, the effects of exercise limitation in COPD were adequately predicted, as evaluated by the area under the curve (AUC) obtained by receiver operating characteristic analysis. The best parameters for this task were R4-R20 (AUC = 0.779) and Ax (AUC = 0.752).
Respiratory oscillometry provides information related to functional capacity in COPD. This method is also able to predict low exercise tolerance in these patients. These findings elucidate the physiological and clinical meaning of the oscillometric parameters, improving the interpretation of these parameters in COPD patients.
呼吸震荡测量法已成为一种检测 COPD 患者呼吸异常的强大方法。然而，这种方法尚未广泛应用于临床实践。出现这种局限性的原因至少部分在于，震荡测量参数的临床意义尚不清楚。在本文中，我们评估了震荡测量法与功能能力的相关性及其在 COPD 中预测异常功能能力的能力。
这项横断面研究调查了由 30 名健康受试者和 30 名 COPD 门诊患者组成的对照组。根据 Glittre-ADL 测试和握力对受试者进行功能能力分类。
本研究初步表明，与功能能力正常的受试者相比，功能能力异常的受试者的阻力（p < 0.05）、电抗面积（Ax，p < 0.01）、阻抗模量（Z4，p < 0.05）和动态顺应性（Cdyn，p < 0.05）值更高。这导致阻力震荡测量参数（R=-0.43）、Cdyn（R=-0.40）、Ax（R = 0.42）和 Z4（R = 0.41）与运动表现之间存在显著且一致的相关性。此外，通过接收者操作特征分析获得的曲线下面积（AUC）评估表明，能够充分预测 COPD 中运动受限的影响。用于此任务的最佳参数是 R4-R20（AUC = 0.779）和 Ax（AUC = 0.752）。
呼吸震荡测量法提供了与 COPD 患者功能能力相关的信息。该方法还能够预测这些患者的低运动耐量。这些发现阐明了震荡测量参数的生理和临床意义，改善了对 COPD 患者这些参数的解释。
