ACCURATE AND CONTINUOUS MEASUREMENT OF CARDIAC OUTPUT

该项目将完成基于半导体激光器的开发 心脏连续热稀释测量系统 输出。我们的系统以体积计加热一团血2-4 使用980 nm二极管激光通过一个 扩散器。位于肺动脉中的热敏电阻测量 血温。该系统连续测量心输出量。 因为它不使用生理盐水团注，因此避免了 血液系统的液体超载。它的精确度比 使用阻性加热器加热血液的系统，因为体积 加热比阻性加热器提供的能量多得多。 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 通过自适应过滤或可选减少 测量与呼吸周期同步。 峰值血流量的实时测量保证了安全性 温度，以及一个不断检查光纤的系统- 光学完整性。因此，该系统将能够 连续测量心输出量，其精度相当于 基于团注的热稀释测量。测量结果将是 自动化，无需操作员干预。这个 由此产生的系统将是安全、可靠和易于使用的。这个 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 将能够测量心脏的导管和系统 输出准确、连续。它为心脏病专家和 目前未对重症监护设施进行测量 有可能，并将自动化这些相同的测量。它有可能 大大提高了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.