Objective: Intradialytic haemodynamic instability is a significant clinical problem, leading to end-organ ischaemia and contributing to morbidity and mortality in haemodialysis patients. Non-invasive continuous blood pressure monitoring is not currently part of routine practice but may aid detection and prevention of significant falls in blood pressure during dialysis. Brachial blood pressure is currently recorded intermittently during haemodialysis via a sphygmomanometer. Current methods of continuous non-invasive blood pressure monitoring tend to restrict movement, can be sensitive to external disturbances and patient movement, and can be uncomfortable for the wearer. Additionally, poor patient blood circulation can lead to unreliable measurements. In this feasibility study we performed an initial validation of a novel method and associated technology to continuously estimate blood pressure using pressure sensors in the extra-corporeal dialysis circuit, which does not require any direct contact with the person receiving dialysis treatment. Method: The paper describes the development of the measurement system and subsequent in vivo patient feasibility study with concurrent measurement validation by Finapres Nova physiological measurement device. Real-time physiological data is collected over the entire period of (typically 4-hour) dialysis treatment. Results: We identify a quasi-linear mathematical function to describe the relationship between arterial line pressure and brachial artery BP, which is confirmed in a patient study. The results from this observational study suggest that it is feasible to derive a continuous measurement of brachial pressure from continuous measurements of arterial and venous line pressures via an empirically based and updated mathematical model. Conclusion: The methodology presented requires no interfacing to proprietary dialysis machine systems, no sensors to be attached to the patient directly, and is robust to patient movement during treatment and also to the effects of the cyclical pressure waveforms induced by the hemodialysis peristaltic blood pump. This represents a key enabling factor to the development of a practical continuous blood pressure monitoring device for dialysis patients.

中文翻译：

---

透析过程中从动脉和静脉线获得的肱动脉压力的无创连续估计的可行性研究

目的：透析中血流动力学不稳定是一个重要的临床问题，会导致终末器官缺血并导致血液透析患者的发病率和死亡率。无创连续血压监测目前不是常规实践的一部分，但可能有助于检测和预防透析期间血压的显着下降。目前在血液透析期间通过血压计间歇性地记录肱动脉血压。当前的连续无创血压监测方法倾向于限制运动，可能对外部干扰和患者运动敏感，并且佩戴者可能不舒服。此外，患者血液循环不良会导致测量结果不可靠。在这项可行性研究中，我们对一种使用体外透析回路中的压力传感器连续估计血压的新方法和相关技术进行了初步验证，该方法不需要与接受透析治疗的人有任何直接接触。方法：本文描述了测量系统的开发和随后的体内患者可行性研究，同时通过 Finapres Nova 生理测量设备进行了测量验证。在整个透析治疗期间（通常为 4 小时）收集实时生理数据。结果：我们确定了一个拟线性数学函数来描述动脉压力和肱动脉血压之间的关系，这在一项患者研究中得到证实。这项观察性研究的结果表明，通过基于经验和更新的数学模型，从动脉和静脉管路压力的连续测量中推导出臂压的连续测量是可行的。结论：所提出的方法不需要与专有的透析机系统接口，不需要直接连接到患者身上的传感器，并且对治疗期间患者的运动以及血液透析蠕动泵引起的周期性压力波形的影响具有鲁棒性。这代表了为透析患者开发实用的连续血压监测设备的关键促成因素。