ACCURATE AND CONTINUOUS MEASUREMENT OF CARDIAC OUTPUT

该项目将完成基于半导体激光器的开发 用于心脏的连续热稀释测量的系统 输出.我们的系统体积加热一团血液2-4 使用980 nm二极管激光器照射， 扩散器位于肺动脉中的热敏电阻测量 血液温度该系统连续测量心输出量 因为它不使用盐水团注， 血液系统的液体过载。它比 使用电阻加热器加热血液的系统， 加热比电阻加热器传递更多的能量。 这提高了温度的信噪比 测量.对呼吸引起的热噪声的敏感性是 通过自适应滤波或通过可选的 测量与呼吸周期的同步。 通过实时测量峰值血液来确保安全性 温度，并通过一个系统，不断检查纤维- 光学完整性该系统将能够 连续测量心输出量，准确度相当于 基于推注的热稀释测量。测量结果将是 自动化，无需操作员干预。的 由此产生的系统将安全、可靠且易于使用。的 该系统的准确性和安全性将在猪模型中得到验证。 建议的商业应用该项目将开发一个 导管和系统将能够测量心脏 准确、连续地输出。它提供心脏病专家和 重症监护设施的测量，目前还没有 这是可能的，并将自动化这些相同的测量。它可以 大大提高这些设施的护理质量。

This project will complete the development of a diode laser based system for continuous thermodilution measurements of cardiac output. Our system volumetrically heats a bolus of blood 2-4 degrees Celsius using 980 nm diode lasers irradiated through a diffuser. A thermistor located in the pulmonary artery measures the blood temperature. This system measures cardiac output continuously since it does not use saline bolus injections and therefore avoids fluid overload of the blood system. It is more accurate than systems that heat blood using resistive heaters because volumetric heating delivers significantly more energy than resistive heaters. which improves the signal-to-noise ratio of the temperature measurements. Sensitivity to respiration-induced thermal noise is reduced through adaptive filtering or through optional synchronization of the measurements to the respiration cycle. Safety is ensured by the real-time measurement of peak blood temperature, and by a system that continually checks the fiber- optic integrity. This system will therefore be capable of continuously measuring cardiac output with accuracy equivalent to bolus-based thermodilution measurements. The measurements will be automated, eliminating the need for operator intervention. The resulting system will be safe, reliable, and easy to use. The accuracy and safety of this system will be verified in a pig model. PROPOSED COMMERCIAL APPLICATIONS This project will develop a catheter and system that will be capable of measuring cardiac output accurately and continuously. It offers cardiologists and critical care facilities measurements that are not currently possible, and will automate those same measurements. It could dramatically increase the quality of care in these facilities.