Unobtrusive and Affordable Blood Pressure Monitoring Via Pulse Transit Time

通过脉搏传输时间进行不引人注目且经济实惠的血压监测

• 批准号: 8898794
• 负责人: RAMAKRISHNA MUKKAMALA
• 金额: $ 66.96万
• 依托单位: MICHIGAN STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8898794
• 关键词: Age; Aorta; Auscultation; Back; Blood; Blood Pressure; Blood Pressure Monitors; Calibration; Cardiovascular system; Catheters; Cellular Phone; Clinical; Data; Detection; Diastole; Diastolic blood pressure; Distal; Event; Face; Gender; Gold; Hand; Health; Health Care Costs; Heart; Human; Hypertension; India; Intensive Care Units; Location; Measurement; Measures; Methods; Modeling; Morbidity - disease rate; Morphologic artifacts; Movement; Outpatients; Patients; Physiologic pulse; Population; Process; Reference Standards; Regression Analysis; Relative (related person); Research; Research Personnel; Resources; Shoes; System; Systole; Technology; Testing; Time; Variant; base; blood pressure regulation; cardiovascular risk factor; cost; design; foot; healthy volunteer; improved; innovation; meetings; model building; mortality; operation; programs; prototype; screening; sensor; skin color; temporal measurement; volunteer

DESCRIPTION (provided by applicant): Hypertension is a major cardiovascular risk factor that is treatable, but undetected or uncontrolled, in many people in the US and India. Unobtrusive and affordable blood pressure (BP) monitoring technology could improve hypertension detection and control, especially in low resource settings. A potential approach for realizing such technology is pulse transit time (PTT). Indeed, PTT correlates with diastolic BP, as evidenced by many studies, and can be estimated simply from the relative timing between proximal and distal arterial waveforms. But, challenges remain in conveniently measuring the two waveforms, accurately estimating PTT, calibrating PTT to BP, and determining systolic BP from PTT. The overall objective is to overcome these challenges and thereby establish technologies for unobtrusive, affordable, and high throughput or individualized BP monitoring via PTT. The specific aims are: (1) to develop inexpensive systems for convenient and accurate contact measurement of proximal and distal arterial waveforms; (2) to develop low cost systems for noncontact measurement of proximal and distal arterial waveforms; (3) to develop methods for estimation of PTT with high accuracy and at both systole and diastole; (4) to develop systems for accurate and convenient calibration of PTT to BP; and (5) to validate the systems and methods against reference BP measurements from humans. Ballistocardiograph (BCG)-based systems in the form of a weighing scale, chair, and shoe will be built and interfaced with photoplethysmograph (PPG) sensors for seamless measurement of the proximal (BCG) and distal (PPG) waveforms. Video processing systems in the form of a webcam and surveillance camera will be created to obtain non-contact PPG waveforms from the face (proximal) and hand (distal) of still and less cooperative people. Arterial modeling methods will be devised to estimate PTT accurately from the entire waveforms, rather than via the conventional foot-to-foot time delay, and at both systole and diastole. Physical oscillometric modeling methods will be designed and combined with arterial modeling methods to construct an accurate, subject-specific calibration curve using a cuff but without involving an operator, and regression methods will be created to form the calibration curve without using a cuff from only basic subject information (e.g., age). Data will be collected from healthy volunteers and hypertensive outpatients with auscultation used for reference BP values and some hypertensive patients in the ICU with unstable BP and catheters in place for gold standard reference BP values. The systems and methods will be tested in various ways including BP error and high BP detection. Finally, the technology will be optimized for cost and integrated to smartphones for ease of operation. Successful completion of this project could ultimately help reduce mortality and morbidity in the US and India.

描述（由申请人提供）：在美国和印度的许多人中，高血压是可治疗但未被发现或未控制的主要心血管危险因素。不引人注目且负担得起的血压（BP）监测技术可以改善高血压检测和控制，尤其是在低资源环境中。实现此类技术的潜在方法是脉冲运输时间（PTT）。实际上，PTT与舒张压BP相关，如许多研究所证明，可以简单地从近端和远端动脉波形之间的相对时机估算。但是，在方便测量两个波形，准确估算PTT，将PTT校准到BP并确定PTT的收缩BP时，挑战仍然存在。总体目的是克服这些挑战，从而建立通过PTT进行不引人注目，负担得起，高吞吐量或个性化的BP监测的技术。具体目的是：（1）开发廉价的系统，以方便，准确的接触率测量近端和远端动脉波形； （2）开发低成本系统，用于近端和远端动脉波形的非连接测量； （3）开发用于高精度和收缩和舒张期PTT估算的方法； （4）开发系统以准确，方便地校准PTT到BP； （5）验证系统和方法，以防止人类的参考BP测量。将建立以秤，椅子和鞋子形式的基于ballist摄影仪（BCG）的系统，并与光摄像仪（PPG）传感器建立并连接，以无缝测量近端（BCG）和远端（PPG）波形。将创建以网络摄像头和监视摄像头的形式的视频处理系统，以从静止和更少合作人员的面部（近端）和手（远端）和手（远端）获得非接触式PPG波形。动脉建模方法将设计为从整个波形中准确估算PTT，而不是通过常规的脚到脚延迟，以及在收缩和舒张期。物理振荡模型方法将与动脉建模方法一起设计并结合使用，以使用袖口来构建精确的，特定于主题的校准曲线，但不会涉及操作员，并且将创建回归方法以形成校准曲线而无需仅使用基本主题信息（例如，年龄）的袖口。数据将从健康的志愿者和高血压门诊患者中收集，该医院用于参考BP值，而ICU中的一些高血压患者则具有不稳定的bp和daperers，用于黄金标准参考BP值。系统和方法将以各种方式进行测试，包括BP误差和高BP检测。最后，该技术将针对成本进行优化，并集成到智能手机以易于操作。成功完成该项目可能最终有助于降低美国和印度的死亡率和发病率。