NON-INVASIVE MEASUREMENT OF MICROVASCULAR BLOOD FLOW DURING MILD EXTERNAL COM

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 静脉性高血压与腿部毛细血管密度、动脉血流量和局部血流量的减少有关。减少 灌流对伤口愈合和组织存活有不利影响，特别是在周围血管疾病患者中。我们假设，轻微的外按压可以恢复静脉高压引起的皮肤和肌肉血流量的减少，而心力衰竭引起的中心静脉压较高的患者腿部压迫引起的微血管血流量将有更大的增加。 与中心静脉压较低的患者和健康受试者相比。股静脉阻塞将被用作健康受试者的静脉高血压模型，外压前、中、后用光体积描记(PPG)测量皮肤和肌肉血流量，用近红外光谱(NIRS)测量肌肉氧合。此外，还将测量有记录的静脉性高血压或心力衰竭患者的皮肤和肌肉对外按压的血流反应。 我们的具体目标是： 目的：测量健康受试者和慢性静脉功能不全(CVI)患者的肌肉血流量(MBF)和皮肤血流量(SBF)，以及轻度外压引起的腿部微循环增加。 目的：测量健康受试者和慢性静脉功能不全(CVI)患者在轻度外压作用下腿部肌肉氧合的变化。 优化持续加压压力，以诱导健康受试者和CVI患者的最大微循环血流量。 优化间歇气动压缩(IPC)的压缩压力、持续时间和频率以获得最大 健康人和CVI患者的微循环血流。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Venous hypertension is associated with decreases in capillary density, arterial inflow, and local blood flow of the leg. Decreased perfusion adversely affects wound healing and viability of tissue, especially in patients with peripheral vascular disease. We hypothesize that mild external compression can restore the decreases in skin and muscle blood flow induced by venous hypertension, and that patients with higher central venous pressures resulting from heart failure will have greater increases in microvascular blood flow induced by leg compression compared to patients with lower central venous pressures and to healthy subjects. Thigh venous occlusion will be used as a model for venous hypertension in healthy subjects, skin and muscle blood flow will be measured using Photoplethysmography (PPG) before, during, and after external compression, and muscle oxygenation will be measured with Near Infrared Spectroscopy (NIRS). In addition, skin and muscle blood flow responses to external compression will be measured in patients with documented venous hypertension or heart failure. Our specific aims are: To measure Muscle Blood Flow (MBF) and Skin Blood Flow (SBF) microcirculatory increases in the leg caused by mild external compression in healthy subjects and patients with Chronic Venous Insufficiency (CVI). To measure muscle oxygenation changes in the leg caused by mild external compression in healthy subjects and patients with Chronic Venous Insufficiency (CVI). To optimize pressures of Continuous Compression to induce maximum microcirculatory blood flow in healthy subjects and patients with CVI. To optimize compression pressures, duration, and frequency of Intermittent Pneumatic Compression (IPC) to induce maximum microcirculatory blood flow in healthy subjects and patients with CVI.