NONINVASIVE BLOOD LOSS MONITOR FOR OBSTETRICS

产后出血是产妇发病和死亡的主要原因 由于缺乏对分娩的评估， 一种测量母体失血量的非侵入性仪器。 一 需要一种无创、方便、廉价的方法来检测和 评估产后失血的程度，以便适当 可以采取干预措施。调查将导致 发展一个测量系统，将满足这一需要提出 本文所 所提出的方法使用传统的指示剂稀释理论， 将18O2稳定的氧同位素用惰性的 更常用的染料和放射性示踪剂的气体。 使用 这些示踪剂、总血容量、Vb、血红蛋白、Hb和失血量， BL，将被测量。建议实验室的初步实验 已经证明了所提出的方法的可行性，并带来了 关于获得大多数特殊用途仪器， 需要设置在这项研究中，所有建议的测量技术 将得到最终验证，方法将得到改进，以满足 产科临床应用所需的准确性标准 实践和研究。在狗身上进行的实验将在 反复放血会造成多大程度的失血 和回输，而Vb，Hb和BL的测量是使用 示踪法随后将使用人类志愿者来验证 这些测量值在其预期生理范围内。BL测量 将在人献血者中观察敏感性。 这些捐助者 将评估捐献后血红蛋白的变化。 最后 将展示将该方法应用于妇女的能力 在分娩的时候 硬件和软件工程的设计， 该器械将进入II期。 拟议的商业应用： 由于非侵入式血容量监测系统目前不 现有的商业装置结合了本发明中开发的方法， 该计划将填补临床实践的迫切需要， 产科..基本上，同一设备将在以下方面发挥重要作用： 其他失血监测情况，包括手术和创伤。

Post partum hemorrhage, a major cause of maternal morbidity and mortality in childbirth has not been quantitatively assessable due to the lack of a noninvasive instrument for the measurement of maternal blood loss. A noninvasive, convenient and inexpensive method is needed to detect and assess the degree of post partum blood loss so that appropriate interventions can be applied. Investigations that will lead to the development a measurement system that will meet this need is proposed herein. The proposed method uses conventional indicator dilution theory, substituting the 18O2 stable oxygen isotope with a combination of inert gases for the more commonly used dyes and radioactive tracers. Using these tracers, total blood volume, Vb, hemoglobin, Hb, and blood loss, BL, will be measured. Preliminary experiments in the proposing laboratory have demonstrated the feasibility of the proposed method and have brought about the acquisition of most of the special purpose instrumentation that will be needed. In this study all the proposed measurement techniques will be conclusively validated and the methods will be refined to meet the accuracy criteria necessary for clinical utility in obstetrics practice as well as research. Experiments in dogs will be conducted in which degrees of blood loss will be imposed by repeated exsanguination and retransfusion while measurements of Vb, Hb, and BL are made using the tracer methods. Subsequently human volunteers will be used to validate these measures within their expected physiologic ranges. BL measurement sensitivity will be observed in human blood donors. Also these donors will be evaluated for hemoglobin changes after donation. Finally demonstration will be made of the ability to apply the method to women during labor. Hardware and software engineering for the design of a device will be relegated to Phase II. PROPOSED COMMERCIAL APPLICATIONS: Since a non-invasive blood volume monitoring system does not presently exist, a commercial device incorporating the methods developed in this program will fill an immediate need in the clinical practice of obstetrics.. Essentially the same device will fill an important role in other blood loss monitoring situations including surgery and trauma.