To date, the clinical use of functional near-infrared spectroscopy (NIRS) to detect cerebral ischemia has been largely limited to surgical settings, where motion artifacts are minimal. In this study, we present novel techniques to address the challenges of using NIRS to monitor ambulatory patients with kidney disease during approximately eight hours of hemodialysis (HD) treatment. People with end-stage kidney disease who require HD are at higher risk for cognitive impairment and dementia than age-matched controls. Recent studies have suggested that HD-related declines in cerebral blood flow might explain some of the adverse outcomes of HD treatment. However, there are currently no established paradigms for monitoring cerebral perfusion in real-time during HD treatment. In this study, we used NIRS to assess cerebral hemodynamic responses among 95 prevalent HD patients during two consecutive HD treatments. We observed substantial signal attenuation in our predominantly Black patient cohort that required probe modifications. We also observed consistent motion artifacts that we addressed by developing a novel NIRS methodology, called the HD cerebral oxygen demand algorithm (HD-CODA), to identify episodes when cerebral oxygen demand might be outpacing supply during HD treatment. We then examined the association between a summary measure of time spent in cerebral deoxygenation, derived using the HD-CODA, and hemodynamic and treatment-related variables. We found that this summary measure was associated with intradialytic mean arterial pressure, heart rate, and volume removal. Future studies should use the HD-CODA to implement studies of real-time NIRS monitoring for incident dialysis patients, over longer time frames, and in other dialysis modalities.

中文翻译：

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使用近红外光谱 (NIRS) 评估血液透析对脑氧合的反应：挑战和解决方案

迄今为止，功能性近红外光谱 (NIRS) 检测脑缺血的临床应用在很大程度上仅限于运动伪影极少的手术环境。在这项研究中，我们提出了新技术来解决在大约 8 小时的血液透析 (HD) 治疗期间使用 NIRS 监测非卧床肾病患者所面临的挑战。与年龄匹配的对照组相比，需要 HD 的终末期肾病患者发生认知障碍和痴呆的风险更高。最近的研究表明，与 HD 相关的脑血流量下降可能解释了 HD 治疗的一些不良结果。然而，目前还没有建立在 HD 治疗期间实时监测脑灌注的范例。在这项研究中，我们使用 NIRS 评估了 95 名流行的 HD 患者在连续两次 HD 治疗期间的脑血流动力学反应。我们在需要修改探针的主要黑人患者队列中观察到显着的信号衰减。我们还观察到一致的运动伪影，我们通过开发一种称为 HD 脑耗氧量算法 (HD-CODA) 的新型 NIRS 方法来解决一致的运动伪影，以确定在 HD 治疗期间脑耗氧量可能超过供应的情况。然后，我们检查了使用 HD-CODA 得出的脑去氧所花费时间的汇总测量与血流动力学和治疗相关变量之间的关联。我们发现，这种总结性测量与透析中平均动脉压、心率和容量清除有关。