Ambulatory cardiovascular monitoring

将获得一套动态数据采集设备，以研究日常生活正常功能和受控实验室条件下的心血管控制。通过动态监测动脉血压、血流速度和组织氧合，我们将启动新的研究领域，扩大我们在心血管动力学研究方面的现有专业知识。该设备的性质也确保了它将在标准实验室条件下以及在非卧床调查中使用。我们率先使用超声成像和多普勒超声血流速度测量来量化在受控实验室条件下从休息到运动过渡期间的整个腿部或前臂肌肉血流量。现在，我们提议开发一种技术，可以在日常生活的动态条件下量化大脑和肌肉的血流量和组织氧合，以及持续的动脉血压：从床上或椅子上站起，站着，步行或攀登台阶。我们继续在使用系留设备的受控条件下研究从仰卧休息的转变(有或不有先前的卧床休息或从国际空间站返回的宇航员)，我们知道，仰卧到坐姿或从坐姿到站立姿势的简单转变会导致动脉血压和脑血流速度短暂下降。我们还不知道的是，在正常过渡到日常生活活动的过程中，血压、脑血流速度和氧合作用会发生什么。我们将研究导致站立时低血压的机制。我们将研究日常生活活动中脑血流量和氧合的变化，重点是为什么定期锻炼可能会增加脑血流量，潜在地有利于老龄化人口的认知功能。总体而言，这些数据将为血压、血流和大脑或锻炼肌肉的氧合之间的相互关系提供新的信息。

A suite of ambulatory data acquisition devices will be acquired to study cardiovascular control under normal functions of daily life as well as in controlled laboratory conditions. With ambulatory monitors of arterial blood pressure, blood flow velocity and tissue oxygenation, we will initiate new research areas that expand on our existing expertise in studies of cardiovascular dynamics. The nature of the equipment also insures that it will be used in standard laboratory conditions as well as ambulatory investigations. We pioneered the use of ultrasound imaging and Doppler ultrasound blood flow velocity measurements to quantify whole leg or forearm muscle blood flow during rest to exercise transitions under controlled laboratory conditions. Now we propose developing techniques that will permit quantification of brain and muscle blood flow and tissue oxygenation along with continuous arterial blood pressure under dynamic conditions of daily life: rising from bed or a chair, standing, walking or climbing steps. We continue to conduct, under controlled conditions with tethered equipment, studies of transitions from supine rest (with or without prior bed rest or in astronauts returning from the International Space Station), and we know that the simple transition of supine to seated, or of seated to standing positions causes a transient drop in arterial blood pressure and cerebral blood flow velocity. What we do not yet know is what happens to blood pressure, brain blood flow velocity and oxygenation with normal transitions to activities of daily life. We will examine mechanisms responsible for low blood pressure on standing. We will examine changes in brain blood flow and oxygenation with activities of daily life with a focus on why regular exercise might increase brain blood flow potentially benefiting cognitive function in an aging population. Overall, these data will provide novel information on the inter-relationships between blood pressure, flow and oxygenation to the brain or exercising muscles.