Telehealth-Enabled Ultrasound-Bioimpedance Viscoelastographic Edema Monitoring

描述(由申请人提供)： 对于许多疾病状态，包括慢性肾脏疾病(CKD)、充血性心力衰竭(CHF)、肝功能衰竭和淋巴水肿，最佳地管理液体状态是一个巨大的临床问题。目前，由熟练的临床医生进行的一系列体检为临床决策提供输入。然而，连续检查是一项挑战，特别是在农村、医疗服务不足的社区，缺乏独立于操作员的定量补水状况评估。使用体重和血压测量的远程监测远程医疗倡议提供了一些信息，但允许快速、可靠、可重复测量水分状态的技术将是一个重大进步。近年来，生物阻抗测量已被证明在监测透析患者方面很有用，在透析患者中，需要测定干重以优化液体状态管理。然而，细胞离子含量的混杂效应阻碍了这项技术的未来发展。我们已经开发了基于应变的生物阻抗测量方法，这将使这一领域向前发展。此外，我们已经为开发一种替代的和补充的方法来量化外周水肿奠定了基础。利用超声应变成像动态、定量地表征地下弹性介质在应力作用下的变化。使用这些应变测量以及生物阻抗读数，我们可以完全表征患者水肿状态的粘弹性参数和孔弹性参数。然而，这项技术尚未经过测试，需要开发和验证。水肿性组织可以看作是一种既含有流体成分又含有固体成分的多孔弹性材料。虽然生物阻抗测量是对组织中体积液体的变化作出反应，但超声测量主要取决于组织的固体成分。结合起来，这些模式有望提供更完整的水肿性组织分析，同时以临床尚未看到的精度量化液体水合状态。与这些对水分状况的担忧平行的是，远程保健和远程医疗形式的远程护理正在成为许多患者群体的重要工具。特别是对于服务不足的农村社区，将重要的可靠的水分状况指标远程传达给医生的能力可以极大地提高我们解决健康问题的能力。这项提议的总体目标是开发一种临床上有用的、坚固的、可重复的、定量的组织水化测量设备，该设备将是低成本的，适合于家庭或远程患者监测，并具有安全的数据处理。我们将首先开发合适的硬件和软件来独立测试超声和生物阻抗在准静态和动态加载条件下检测多孔弹性结构变化的能力，从而实现这一点。基于收集的数据的算法和模型将使用PIV、称重传感器和压力传感器测量来开发和验证。与此并行的是，将开发一个远程医疗计划，包括所需的无线功能以及对警报和警报系统的初步测试，一旦液体水合状态读数被纳入远程监测系统，就可以使用这些警报和警报系统。最后，将开发一种紧凑、方便的设备，用于临床测试，结合超声波和生物阻抗模式，准确和定量地确定周围肢体的组织水化程度，并通过远程医疗通信线路安全地传输数据。利尿剂或体外治疗患者的管理需要适当的容量状态评估。这对于各种临床情况都很重要。重要的是，这项提案支持退伍军人管理局远程保健倡议，并将改善需要远程健康监测的退伍军人的健康。 公共卫生相关性： 这项提议将开发和测试一种新的设备，该设备可以准确地测量多余的液体(浮肿)，以指导治疗，从而改善肾病和心脏病患者的健康。该提案还将把先进的远程监测方法(远程健康)与这一新设备相结合，以满足美国服务不足地区患者的临床需求。

DESCRIPTION (provided by applicant): There is an enormous clinical problem in optimally managing the fluid status for a number of disease states, including chronic kidney disease (CKD), congestive heart failure (CHF), liver failure, and lymphedema. Currently, serial physical examinations by a skilled clinician provide the input for clinical decision making. However, serial examinations are a challenge, especially in rural, medically underserved communities and quantitative, operator independent hydration status assessments are lacking. Remote monitoring telehealth initiatives using weights and blood pressure measurements provide some information, but technology allowing rapid, robust, repeatable measurements of hydration status would be a major advance. In recent years, bioimpedance measurements have been shown to be useful in monitoring dialysis patients, where a dry weight determination is needed for optimal fluid status management. However, confounding effects from cellular ionic content hamper future evolution of this technique. We have developed approaches for strain-based bioimpedance measurements that will allow this field to advance. In addition, we have laid the groundwork to develop an alternative and complementary method for quantifying peripheral edema. The use of ultrasound strain imaging dynamically and quantitatively characterizes changes of a subsurface elastic medium under stress. Using these strain measurements, along with bioimpedance readings, we can completely characterize the visco- and poro-elastic parameters of a patient's edematous state. However, this technique is untested and needs to be developed and validated. Edematous tissue can be viewed as a poroelastic material containing both fluid and solid components. While bioimpedance measurements are responsive to volume fluid changes in tissue, ultrasound measurements primarily depend on the solid component of tissue. Combined, these modalities promise to offer a more complete analysis of edematous tissue while quantifying fluid hydration status with a precision yet seen clinically. Parallel to these concerns over hydration status, remote care in the form of telehealth and telemedicine is emerging as an important tool for numerous patient groups. Especially for rural, underserved communities, the ability to remotely communicate important reliable indicators of hydration status to their physicians can dramatically improve our ability to address health concerns. The overall goal of this proposal is to develop a clinically useful, robust, reproducible, quantitative tissue hydration measurement apparatus that will be low-cost, suitable for home or remote patient monitoring, with secure data handling. We will accomplish this by first developing appropriate hardware and software to independently test the ability of ultrasound and bioimpedance to detect changes in poroelastic structures under quasi-static and dynamic loading conditions. Algorithms and models based on the collected data will be developed and validated using PIV, load cell, and pressure transducer measurements. Parallel to this, a telehealth program will be developed including both the wireless capabilities needed as well as preliminary testing on alerts and warning systems that could be utilized once fluid hydration status readings are incorporated into remote monitoring regimes. Finally, a compact, convenient device will be developed ready for clinical testing combining both ultrasound and bioimpedance modalities to accurately and quantitatively determine tissue hydration of peripheral extremities and transmit the data securely over telehealth communication lines. Management of patients with diuretics or extracorporeal therapies requires proper assessment of volume status. This is important for a wide variety of clinical situations. Importantly, this proposal supports the Veterans Administration telehealth initiative and will improve the health of Veterans needing remote health monitoring. PUBLIC HEALTH RELEVANCE: This proposal will develop and test a novel device that accurately measures excess fluids (edema) to guide therapy that will improve the health of people with kidney disease and heart disease. The proposal will also integrate advanced remote monitoring methods (telehealth) with this novel device to meet the clinical needs of patients in underserved regions in the United States.