Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Republic of Korea.
Interdisciplinary Program in Bioengineering, Graduate School, Seoul National University, Seoul, Republic of Korea.
Ultrasonics. 2021 Aug;115:106457. doi: 10.1016/j.ultras.2021.106457. Epub 2021 May 2.
Mechanical circulatory support systems (MCSSs) are crucial devices for transplants in patients with heart failure. The blood flowing through the MCSS can be recirculated or even stagnated in the event of critical blood flow issues. To avoid emergencies due to abnormal changes in the flow, continuous changes of the flowrate should be measured with high accuracy and robustness. For better flowrate measurements, a more advanced ultrasonic blood flowmeter (UFM), which is a noninvasive measurement tool, is needed. In this paper, we propose a novel UFM sensor module using a novel algorithm (Xero) that can exploit the advantages of both conventional cross-correlation (Xcorr) and zero-crossing (Zero) algorithms, using only the zero-crossing-based algorithm. To ensure the capability of our own developed and optimized ultrasonic sensor module for MCSSs, the accuracy, robustness, and continuous monitoring performance of the proposed algorithm were compared to those of conventional algorithms after application to the developed sensor module. The results show that Xero is superior to other algorithms for flowrate measurements under different environments and offers an error rate of at least 0.92%, higher robustness for changing fluid temperatures than conventional algorithms, and sensitive responses to sudden changes in flowrates. Thus, the proposed UFM system with Xero has a great potential for flowrate measurements in MCSSs.
机械循环支持系统（MCSS）是心力衰竭患者移植的关键设备。在出现严重血流问题的情况下，流经 MCSS 的血液可能会再循环甚至停滞。为避免因流量异常变化而引发的紧急情况，应高精度且稳健地连续测量流量变化。为了更好地测量流量，需要更先进的超声血流计（UFM），它是一种非侵入性测量工具。在本文中，我们提出了一种新型的 UFM 传感器模块，该模块使用一种新算法（Xero），该算法可以利用传统互相关（Xcorr）和过零（Zero）算法的优势，仅使用基于过零的算法。为了确保我们自主开发和优化的超声传感器模块对 MCSS 的适用性，在将该算法应用于开发的传感器模块后，比较了其准确性、稳健性和连续监测性能与传统算法的性能。结果表明，Xero 在不同环境下的流量测量中优于其他算法，其误差率至少为 0.92%，在流体温度变化方面比传统算法具有更高的稳健性，并且对流量的突然变化具有敏感的响应。因此，具有 Xero 的新型 UFM 系统在 MCSS 中的流量测量方面具有很大的潜力。
