A whole-cortex fNIRS system to shine light on the problem of post-operative delirium

项目总结：对于60岁以上的人，手术的危险不仅包括手术， 并发症：术后谵妄（POD）是一个已确定的问题，报告的发生率 超过50%的手术，包括心脏手术。近390万老年患者面临 仅因心脏手术导致POD。与POD相关的危险后遗症包括增加 围手术期发病率、住院时间延长和痴呆风险增加， 其成本约为1520亿美元。尽管有大量与POD相关的调查， 已经出现了令人满意的术中生物标志物或术前预测因子，可以预防或减少 功能障碍，暴露了我们对症状和病情贡献者的理解存在重大差距。新 需要评估方法来指导外科手术的改变和干预， 可降低POD的发生率。 谵妄研究的一个共同缺点是缺乏意识， 了解手术期间的神经认知变化。因此，这些研究不足以 确定手术的哪些方面会导致谵妄，并指导外科手术的改变， 手术期间的神经监测在很大程度上限于不确定的脑血氧测定 和脑电图（EEG）研究。脑血氧测定缺乏对整个皮层的透视， 手术-缺失谵妄生物标志物的潜在关键标志; EEG研究受到低空间分辨率的影响。 分辨率和对信号伪影的高敏感性。此外，目前的工具体积庞大并且具有不可靠的性能。 粘性附件易引起运动、活动受限、安装困难和不一致 由于围手术期工作流程中预期的传感器定位变化而导致的数据质量下降。 相比之下，基于功能近红外光谱（fNIRS）的围手术期监测的整体 皮层将提供更好的空间分辨率，降低对伪影的敏感性，并更好地观察大脑 术前术中术后我们提出了一种新的fNIRS帽围手术期监测，以克服 当前神经成像技术的可用性和传感限制。这顶帽子将改善我们的 第一代无线fNIRS系统（鲍登），并利用我们的新型颗粒的固定功能， 干扰技术（韦伯斯特）。在目标1中，我们将开发fNIRS电子器件，将其与颗粒集成， 干扰并进行机械和电气测试。在目标2中，我们将进行i）人类试点研究， 在模拟手术室中确认结果的生理有效性，以及ii）嵌套的术中飞行员 研究（Shah），以确认检测与麻醉护理相关的fNIRS数据变化的可行性 记录如果成功，我们的新型帽将能够更全面地研究术中贡献者， POD和其他术后认知障碍的指标。

PROJECT SUMMARY: For individuals > 60 years of age, the dangers of surgery include more than surgical complications: postoperative delirium (POD) is an established concern with reported incidence rates that exceed 50% for certain surgeries, including cardiac surgery. Nearly 3.9 million elderly patients are at risk for POD due to cardiac surgery alone. The dangerous sequelae associated with POD include increased perioperative morbidity, increased duration of hospitalization and increased risk of dementia, the additional costs of which amount to ~$152 billion. Despite the large number of investigations related to POD, no satisfactory intraoperative biomarkers or preoperative predictors have emerged that can prevent or curtail the dysfunction, exposing a critical gap in our understanding of signs and contributors to the condition. New methods of assessment are needed to guide changes and interventions in surgical procedures that can reduce the incidence of POD. A common shortcoming in research studies on delirium has been the lack of awareness and understanding of neurocognitive changes during surgery. Consequently, such studies are inadequate to identify what aspects of surgery contribute to delirium and to guide changes to surgical procedures that can possibly prevent it. Neuromonitoring during surgery has been largely limited to inconclusive cerebral oximetry and electroencephalography (EEG) studies. Cerebral oximetry lacks perspective of the whole cortex during surgery – missing potentially critical landmarks for delirium biomarkers; EEG studies suffer from low spatial resolution and high susceptibility to signal artifacts. Moreover, current tools are bulky and have unreliable adhesive attachments that imbue susceptibility to motion, mobility limitations, setup difficulty and inconsistency in data quality due to changes in sensor positioning expected during the perioperative workflow. In contrast, functional near infrared spectroscopy (fNIRS)-based perioperative monitoring of the whole cortex would offer better spatial resolution, lower susceptibility to artifacts, and a better view of the brain before, during and after surgery. We propose a novel fNIRS cap for perioperative monitoring to overcome the usability and sensing limitations of current neuroimaging technologies. This cap will improve on our first-generation wireless fNIRS system (Bowden) and leverage the immobilizing features of our novel granular jamming technology (Webster). In Aim 1 we will develop the fNIRS electronics, integrate them with granular jamming and perform mechanical and electrical testing. In Aim 2 we will perform i) a human pilot study to confirm the physiological validity of the results in a mock operating room and ii) a nested intraoperative pilot study (Shah) to confirm the feasibility to detect changes in fNIRS data correlated with the anesthesia care record. If successful, our novel cap will enable more comprehensive study of intraoperative contributors to and indicators of POD and other postoperative cognitive disorders.