Dutt Abhilash Guru, Verling Michaela, Karlen Walter
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:3985-3988. doi: 10.1109/EMBC44109.2020.9175298.
Bioimpedance monitoring provides a non-invasive, safe and affordable opportunity to monitor total body water for a wide range of clinical applications. However, the measurement is susceptible to variations in posture and movement. Existing devices do not account for these variations and are therefore unsuitable to perform continuous measurements to depict trend changes. We developed a wearable bioimpedance monitoring system with embedded real-time posture detection using a distributed accelerometer network. We tested the device on 14 healthy volunteers following a standardized protocol of posture change and evaluated the agreement with a commercial device. The impedance showed a high correlation (r>0.98), a bias of -4.5 Ω, and limits of agreement of -30 and 21 Ω. Context-awareness was achieved with an accuracy of 94.6% by classifying data from two accelerometers placed at the upper and lower leg. The calculated current consumption of the system was as low as 10 mA during continuous measurement operation, suggesting that the system can be used for continuous measurements over multiple days without charging. The proposed motion-aware design will enable the measurement of relevant bioimpedance parameters over long periods and support informed clinical decision making.
生物阻抗监测为广泛的临床应用提供了一种无创、安全且经济实惠的全身水监测方法。然而，该测量易受姿势和运动变化的影响。现有设备未考虑这些变化，因此不适用于进行连续测量以描绘趋势变化。我们开发了一种可穿戴生物阻抗监测系统，该系统使用分布式加速度计网络进行嵌入式实时姿势检测。我们按照标准化的姿势变化协议在14名健康志愿者身上测试了该设备，并评估了其与商用设备的一致性。阻抗显示出高度相关性（r>0.98），偏差为-4.5Ω，一致性界限为-30和21Ω。通过对放置在小腿和大腿的两个加速度计的数据进行分类，实现了94.6%的上下文感知准确率。系统在连续测量操作期间的计算电流消耗低至10 mA，这表明该系统无需充电即可连续测量多天。所提出的运动感知设计将能够长时间测量相关生物阻抗参数，并支持明智的临床决策。
