Department of Pulmonary Diseases, Ataturk University School of Medicine, 25240, Yakutiye, Erzurum, Turkey.
Pflugers Arch. 2024 Oct;476(10):1529-1538. doi: 10.1007/s00424-024-02993-2. Epub 2024 Jul 24.
Near-infrared spectroscopy (NIRS) can be used to demonstrate muscle metabolism and oxygenation. NIRS-based oximeters enable the noninvasive measurement of static and dynamic muscle oxygenation. This study aimed to evaluate the relationship between NIRS readings and exercise capacity in group E COPD patients. The prospective study included 40 patients with group E COPD who presented to our outpatient clinic between May 2021 and June 2022. The patients were evaluated with pulmonary function testing, 6-Minute Walk Test (6MWT), echocardiography, and dyspnea and quality of life assessments. NIRS muscle oxygen saturation (SmO) levels at the start and end of the 6MWT were obtained. 6MWT distance was positively correlated with intercostal SmO and fingertip SO at the start (R = 0.679, p ≤ 0.001 and R = 0.321, p = 0.04, respectively) and end of the 6MWT (R = 0.693, p ≤ 0.001 and R = 0.635, p ≤ 0.001, respectively) and negatively correlated with the number of hospitalizations due to exacerbations in the last year and mean pulmonary arterial pressure (R = - 0.648, p ≤ 0.001 and R = - 0.676, p ≤ 0.001, respectively). SF-36 score was positively correlated with intercostal SmO at the beginning of the 6MWT (R = 0.336, p = 0.03). Intercostal SmO levels at the start of the 6MWT positively correlated with diffusing capacity of the lung for carbon dioxide (DLCO) (R = 0.388, p = 0.01) and ratio of DLCO to alveolar volume (DLCO/VA) levels (R = 0.379, p = 0.02), and these correlations persisted more strongly after the 6MWT (R = 0.524, p = 0.01; R = 0.500, p = 0.01, respectively). NIRS is a practical and noninvasive method for measuring muscle oxygenation and can be used as an alternative to 6MWT in the evaluation of exercise capacity in patients with group E COPD.
近红外光谱（NIRS）可用于显示肌肉代谢和氧合情况。基于 NIRS 的血氧计可实现静态和动态肌肉氧合的无创测量。本研究旨在评估 E 组 COPD 患者的 NIRS 读数与运动能力之间的关系。这项前瞻性研究纳入了 2021 年 5 月至 2022 年 6 月期间在我们门诊就诊的 40 名 E 组 COPD 患者。对患者进行了肺功能测试、6 分钟步行试验（6MWT）、超声心动图、呼吸困难和生活质量评估。在 6MWT 开始和结束时获得了 NIRS 肌肉氧饱和度（SmO）水平。6MWT 距离与肋间 SmO 和指尖 SO 在 6MWT 开始（R = 0.679，p ≤ 0.001 和 R = 0.321，p = 0.04）和结束（R = 0.693，p ≤ 0.001 和 R = 0.635，p ≤ 0.001）时呈正相关，与过去一年因恶化而住院的次数和平均肺动脉压呈负相关（R = - 0.648，p ≤ 0.001 和 R = - 0.676，p ≤ 0.001）。SF-36 评分与 6MWT 开始时的肋间 SmO 呈正相关（R = 0.336，p = 0.03）。6MWT 开始时的肋间 SmO 水平与二氧化碳弥散量（DLCO）（R = 0.388，p = 0.01）和 DLCO 与肺泡容积比（DLCO/VA）（R = 0.379，p = 0.02）呈正相关，这些相关性在 6MWT 后更强烈（R = 0.524，p = 0.01；R = 0.500，p = 0.01）。NIRS 是一种实用且无创的肌肉氧合测量方法，可作为 E 组 COPD 患者运动能力评估的 6MWT 替代方法。
