Design of a bracelet embedding high-frequency ultrasound transducers to acquire venous blood echogenicity spectral data for patient monitoring

每天，入住重症监护病房的病人都会出现并发症，而且往往是致命的病情恶化。严重的并发症导致多器官功能综合症（MODS），死亡率为41%。MODS的特点是严重的急性炎症反应，导致血管血栓形成、感染性休克和器官和组织的氧合受损。炎症血液标记物可用于患者监测，但结果在采样后数小时或数天获得。在需要快速医疗决策以提高患者生存可能性的情况下，这些血液检查通常没有价值。我们在此拨款申请中提出一种新的床侧超声技术，以持续监测炎症状态，以获得最佳的患者治疗。红细胞（RBC）聚集是炎症的强烈标志，具有通过超声成像提供连续监测能力的独特优势。该拨款提议开发和整合技术，以提供基于高频超声光谱数据分析的即时患者监测，以测量在手臂或脚踝浅静脉内流动的红细胞的时变聚类。猪模型的临床前结果证实了超声监测炎症促进红细胞聚集的能力。所提出的算法已获得专利，我们建议开发一种便携式仪器，用于受限区域，如手术室和重症监护病房。该仪器将由一个手镯组成，无害地附着在患者身上，并嵌入高频超声换能器，一个控制血流的闭塞装置，以及一个定位装置，用于收集由小型化计算机仪器处理的超声数据，以向临床医生提供关于红细胞聚集状态的反馈。

Every day, patients admitted to critical care units are experiencing complications and oftenfatal deteriorating conditions. Severe complications leading to the syndrome of multiple organdysfunctions or MODS result in a mortality rate at 41%. The MODS condition is characterizedby a severe acute inflammatory reaction leading to vascular thrombosis, septic shock andimpaired oxygenation of organs and tissues. Inflammatory blood markers can be prescribedfor patient monitoring but results are obtained hours or days after sampling. In conditionswhere rapid medical decisions are required to improve the likelihood of patient survival, thoseblood tests are often of no value. We propose in this grant application a new bed sideultrasound technology to continuously monitor the state of inflammation for optimum patienttreatment.Red blood cell (RBC) aggregation is a strong marker of inflammation and has the uniqueadvantage of offering continuous monitoring capability through ultrasound imaging. This grantproposes the development and integration of technologies to provide point-of-care patientmonitoring based on the analysis of high-frequency ultrasound spectral data to measure thetime-varying clustering of RBCs flowing within a superficial vein of the arm or ankle.Preclinical results in a porcine model confirmed the capability of monitoring inflammationpromotedaggregation of RBCs with ultrasound. The proposed algorithm is patented and wepropose the development of a portable instrument for use in restricted areas as surgeryrooms and intensive care units. This instrument will consist in a bracelet attached innocuouslyto the patient and embedding high-frequency ultrasound transducers, an occluding device tocontrol the blood flow, and a positioning device to collect ultrasound data processed by aminiaturized computer instrument to provide feedback to clinicians on the state of RBCaggregation.