Department of Electronic and Information Engineering, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen, People's Republic of China. Authors contributed equally to this work.
Physiol Meas. 2018 Sep 5;39(9):095002. doi: 10.1088/1361-6579/aad902.
Cuffless blood-pressure (BP) estimation has attracted widespread interest owing to its potential for long-term, non-invasive BP monitoring. But it is still impractical in clinical settings, mainly owing to ongoing challenges with respect to accuracy in hypertensive patients. To better estimate the BP, the current study proposes a new cuffless estimation method that includes a sympathetic tone, which has been reported with a varied pattern in hypertensive patients.
First, the heart-rate variability of all subjects is investigated, and a new parameter, the heart-rate power spectrum ratio (HPSR), is proposed to indicate BP dynamics under sympathetic regulation. Then, a new BP estimation model is constructed by integrating HPSP with the pulse transit time (PTT) and photoplethysmography intensity ratio. The estimation accuracy is further evaluated by making comparisons with the standard sphygmomanometer BP on 60 subjects (29 hypertensive and 31 normotensive).
A significant increase in HPSR was observed in hypertensive patients compared to normotensive subjects. Of the 60 subjects, the estimation accuracy was 0.73 ± 10.04 mmHg for systolic BP (SBP) and 0.90 ± 7.10 mmHg for diastolic BP (DBP) in hypertensive patients, which is comparable to 0.54 ± 7.52 mmHg for SBP and 0.82 ± 6.20 mmHg for DBP in normotensive subjects. Furthermore, the proposed method overperformed the traditional PTT-based algorithm by reducing the 3 mmHg error in the standard deviation in hypertensive patients.
The results of the current study demonstrate that the inclusion of factors associated with autonomic activities in the BP estimation model would improve the BP estimation accuracy, especially for hypertensive subjects.
由于无袖带血压（BP）监测具有长期、非侵入性监测 BP 的潜力，因此引起了广泛关注。但由于在高血压患者中准确性方面持续存在挑战，因此在临床环境中仍然不切实际。为了更好地估计 BP，本研究提出了一种新的无袖带估计方法，该方法包括自主神经活动，据报道，高血压患者的自主神经活动模式存在差异。
首先，研究所有受试者的心率变异性，并提出一个新的参数，即心率功率谱比（HPSR），以指示交感神经调节下的 BP 动力学。然后，通过将 HPSR 与脉搏传输时间（PTT）和光容积脉搏波强度比相结合，构建新的 BP 估计模型。通过将标准血压计的血压与 60 名受试者（29 名高血压和 31 名正常血压）进行比较，进一步评估估计准确性。
与正常血压受试者相比，高血压患者的 HPSR 显著增加。在 60 名受试者中，高血压患者的收缩压（SBP）和舒张压（DBP）的估计准确率分别为 0.73 ± 10.04 mmHg 和 0.90 ± 7.10 mmHg，与正常血压受试者的 0.54 ± 7.52 mmHg 和 0.82 ± 6.20 mmHg 相当。此外，与传统基于 PTT 的算法相比，该方法通过减少高血压患者标准偏差中的 3 mmHg 误差，提高了 BP 估计的准确性。
本研究结果表明，在 BP 估计模型中纳入与自主活动相关的因素将提高 BP 估计的准确性，特别是对于高血压患者。
