Department of Electrical Engineering, Indian Institute of Technology (IIT) Madras, Chennai, India.
Physiol Meas. 2017 Nov 30;38(12):2122-2140. doi: 10.1088/1361-6579/aa9550.
A novel photoplethysmograph probe employing dual photodiodes excited using a single infrared light source was developed for local pulse wave velocity (PWV) measurement. The potential use of the proposed system in cuffless blood pressure (BP) techniques was demonstrated.
Initial validation measurements were performed on a phantom using a reference method. Further, an in vivo study was carried out in 35 volunteers (age = 28 ± 4.5 years). The carotid local PWV, carotid to finger pulse transit time (PTT) and pulse arrival time at the carotid artery (PAT) were simultaneously measured. Beat-by-beat variation of the local PWV due to BP changes was studied during post-exercise relaxation. The cuffless BP estimation accuracy of local PWV, PAT, and PTT was investigated based on inter- and intra-subject models with best-case calibration.
The accuracy of the proposed system, hardware inter-channel delay (<0.1 ms), repeatability (beat-to-beat variation = 4.15%-11.38%) and reproducibility of measurement (r = 0.96) were examined. For the phantom experiment, the measured PWV values did not differ by more than 0.74 m s compared to the reference PWV. Better correlation was observed between brachial BP parameters versus local PWV (r = 0.74-0.78) compared to PTT (|r| = 0.62-0.67) and PAT (|r| = 0.52-0.68). Cuffless BP estimation using local PWV was better than PTT and PAT with population-specific models. More accurate estimates of arterial BP levels were achieved using local PWV via subject-specific models (root-mean-square error ⩽2.61 mmHg).
A reliable system for cuffless BP measurement and local estimation of arterial wall properties.
开发了一种采用单红外光源激励双光电二极管的新型光电容积脉搏波描记术探头，用于局部脉搏波速度（PWV）测量。该系统在无袖带血压（BP）技术中的潜在应用得到了验证。
首先在体模上使用参考方法进行了初步验证测量。然后，在 35 名志愿者（年龄=28±4.5 岁）中进行了体内研究。同时测量了颈动脉局部 PWV、颈动脉到手指脉搏传递时间（PTT）和颈动脉脉搏到达时间（PAT）。研究了运动后放松期间由于血压变化导致的局部 PWV 的逐拍变化。基于最佳情况下的校准，通过个体间和个体内模型研究了局部 PWV、PAT 和 PTT 的无袖带 BP 估计精度。
检查了该系统的准确性、硬件通道间延迟（<0.1 ms）、重复性（逐拍变化=4.15%-11.38%）和测量的可重复性（r=0.96）。对于体模实验，与参考 PWV 相比，测量的 PWV 值相差不超过 0.74 m s。与 PTT（|r|=0.62-0.67）和 PAT（|r|=0.52-0.68）相比，局部 PWV 与肱动脉 BP 参数的相关性更好（r=0.74-0.78）。使用基于人群的模型，无袖带 BP 估计使用局部 PWV 优于 PTT 和 PAT。使用基于个体的模型，通过局部 PWV 可以更准确地估计动脉 BP 水平（均方根误差≤2.61 mmHg）。
这是一种用于无袖带 BP 测量和局部动脉壁特性估计的可靠系统。
