Non-Invasive Carotid Artery Measurements for Continuous Intracranial Pressure Monitoring

项目摘要 持续颅内压（ICP）监测是危重神经系统疾病的重要监测工具 患者提供 对疾病严重程度的重要见解，用于指导医疗管理 .然而，在这方面， ICP 监测需要高度侵入性的程序，这会带来颅内出血和感染的风险。 因此，ICP监测的临床适应症是一个有争议的话题，高达50%的创伤性脑损伤 符合ICP监测器推荐标准的患者从未接受过ICP监测器。22此外，近一半的患者 在没有ICP监测仪的情况下进入神经重症监护室（Neuro-ICU），随后出现ICP升高 ICP.1不幸的是，即使符合条件的患者也仅在神经ICU中提供ICP监测。后 如果没有足够的恢复，即使他们仍然处于高位，他们也会被转移到一个没有监视器的降压单元。 颅内压升高和潜在致命脑疝的风险。因此，显然存在未满足的需求， 用于连续ICP监测的非侵入性方法。 我们建议开发一种非侵入式传感系统，通过将心跳与血压相关联来连续监测ICP。 颈动脉血压和颅内压 先前的研究已经证明，中心主动脉波形检测在 颈动脉的颅外部分与ICP波形非常相似。3 -10在我们以前的工作中，我们 开发了高灵敏度适形传感器，能够以最小的 压平压力 36，37 W 我们还展示了一种新的压力估计算法， 在外科和ICU患者中进行高精度桡动脉BP测量。 13通过结合我们高度敏感的 传感器与我们的通用压力估计算法， 我们假设我们可以非侵入性地 通过开发参数估计模型来连续监测ICP，以将我们的传感器的颈动脉BP 使用Neuro-ICU患者的记录进行ICP波形测量，用于培训和验证 . 研究 还证明了其他ICP波形衍生指数用于评估颅内压的临床实用性。 14 -18由于颈动脉BP和动脉血压之间的形态学相似性， 和ICP波形，我们假设这些波形特征也可以应用于我们的颈动脉BP 测量和传感器推导的ICP估计，以获得对患者神经系统状态的独特见解， 帮助医疗决策。不 该项目的研究结果有可能为未来的研究奠定基础。 颈动脉血压波形特征作为颅内压替代指标的研究。而且我 F 成功，我们提出的非侵入性，连续ICP监测不仅有可能提高 在更广泛的患者范围内进行神经监测，但也创造了现有的范式转变， 临床方案有利于更积极的ICP监测。

PROJECT SUMMARY Continuous intracranial pressure (ICP) monitoring is an important surveillance tool for critically ill neurologic patients that provides critical insights on disease severity for guiding medical management . However, ICP monitoring requires a highly invasive procedures that incurs risks for intracranial hemorrhage and infection.24–28 Thus, the clinical indications for ICP monitoring are a topic of debate and up to 50% of traumatic brain injury patients who fulfill recommendation criteria for an ICP monitor never receive it.22 Moreover, nearly half of patients admitted to the Neuro-Intensive Care Unit (Neuro-ICU) without an ICP monitor go on to later develop elevated ICP.1 Unfortunately, even eligible patients are only provided ICP monitoring while in the Neuro-ICU. After adequate recovery, they are transferred to a step-down unit without a monitor even though they are still at high risk for developing elevated ICPs and potentially fatal brain herniation. Therefore, there is a clear unmet need for a non-invasive approach to continuous ICP monitoring. We propose to develop a non-invasive sensing system to continuously monitor ICP by correlating beat- to-beat carotid artery BP to ICP. Prior studies have demonstrated that central aortic waveforms detected at the extracranial portion of the carotid artery closely resemble ICP waveforms.3-10 In our previous work, we developed highly sensitivity conformal sensors capable of measuring carotid artery BP waveforms with minimal applanation pressure. 36,37 W e have also demonstrated a novel pressure estimation algorithm that can sustain high accuracy radial artery BP measurements in surgical and ICU patients. 13 By combining our highly sensitive sensors with our generalizable pressure estimation algorithm, we hypothesize that we can non-invasively and continuously monitor ICP by developing a parameter estimation model to correlate our sensor's carotid BP measurements with ICP waveforms using recordings from Neuro-ICU patients for training and validation . Studies have also demonstrated the clinical utility of other ICP waveform-derived indices for assessing intracranial compliance and prognosticating patient outcomes.14–18 Due to the morphological similarity between carotid BP and ICP waveforms, we hypothesize that these waveform features can also be applied to our carotid BP measurements and sensor-derived ICP estimations to gain unique insights on patient neurologic status that can aid medical decision-making. T he findings of this project have the potential to form the basis for future investigations on utilizing the waveform features of carotid BP as a proxy measure of ICP. Moreover, i f successful, our proposed non-invasive, continuous ICP monitor has the potential to not only enhance neurologic monitoring across a broader range of patients, but also create a paradigm shift in existing clinical protocols in favor of more proactive ICP surveillance.