Investigating the physiological mechanisms of the photoplethysmogram features for blood pressure estimation
Investigating the physiological mechanisms of the photoplethysmogram features for blood pressure estimation
复制标题
研究用于血压估计的光电体积描记图特征的生理机制
DOI：
10.1088/1361-6579/ab7d78
复制
发表时间：
2020-04-01
影响因子：
3.2
通讯作者：
Chen, Fei
中科院分区：
文献类型：
--
作者：
Lin, Wan-Hua;Li, Xiangxin;Chen, Fei
目的：光电容积脉搏波（PPG）信号已被广泛用于无袖带且连续地估计血压（BP）。为了准确估计血压，人们已经提出并从PPG信号中提取了许多不同的PPG特征。然而，基于PPG的血压估计的潜在生理机制仍然不清楚，特别是与各种PPG特征相对应的机制。在这项研究中，对用于血压估计的PPG特征的生理机制进行了研究，这可能会提供进一步的见解。
方法：设计了冷刺激实验和运动试验，分别用于改变外周血管总阻力（TPR）和心输出量（CO）。在整个实验过程中，记录了12名健康受试者的瞬时血压和连续的PPG信号。从PPG的原始波、一阶导数波和二阶导数波中总共提取了65个PPG特征。比较了冷刺激阶段和运动早期恢复阶段PPG特征变化与基线阶段的显著性。
主要结果：与基线阶段相比，特定强度的PPG特征在冷刺激阶段有显著变化（p < 0.05），表明它们与TPR相关。与基线阶段相比，特定时间的PPG特征在运动早期恢复阶段有显著变化（p < 0.05），表明它们与CO相关。大多数与斜率和面积相关的PPG特征在冷刺激阶段和运动早期恢复阶段都有明显变化，表明它们应该与TPR和CO都相关。
意义：这项研究的结果解释了用于血压估计的PPG特征背后的内在生理机制，并为探索PPG特征的更多诊断应用提供了见解。
Objective: Photoplethysmogram (PPG) signals have been widely used to estimate blood pressure (BP) cufflessly and continuously. A number of different PPG features have been proposed and extracted from PPG signals with the aim of accurately estimating BP. However, the underlying physiological mechanisms of PPG-based BP estimation still remain unclear, particularly those corresponding to various PPG features. In this study, the physiological mechanisms of PPG features for BP estimation were investigated, which may provide further insight. Approach: Experiments with cold stimuli and an exercise trial were designed to change the total peripheral vascular resistance (TPR) and cardiac output (CO), respectively. Instantaneous BP and continuous PPG signals from 12 healthy subjects were recorded throughout the experiments. A total of 65 PPG features were extracted from the original, the first derivative, and the second derivative waves of PPG. The significance of the change of PPG features in the cold stimuli phase and in the early exercise recovery period was compared with that in the baseline phase. Main results: Intensity-specific PPG features changed significantly (p < 0.05) in the cold stimuli phase compared with the baseline phase, demonstrating that they were TPR-correlated. Time-specific PPG features changed significantly (p < 0.05) in the early exercise recovery period compared with the baseline phase, suggesting they were CO-correlated. Most of the PPG features associated with slope and area changed obviously both in the cold stimuli phase and in the early exercise recovery period, indicating that they should be TPR-correlated and CO-correlated. Significance: The findings of this study explained the intrinsic physiological mechanisms underlying PPG features used for BP estimation, and provided insights for exploring more diagnostic applications of the PPG features.