Probing the order within neonatal heart rate variability
Probing the order within neonatal heart rate variability
复制标题
DOI：
10.1203/00006450-199806000-00017
复制
发表时间：
1998-06-01
影响因子：
3.6
通讯作者：
Moorman, JR
中科院分区：
文献类型：
--
作者：
Nelson, JC;Rizwan-Uddin;Moorman, JR
新生儿患病期间心率变异性（HRV）改变的机制尚不清楚。一种可能性是，HRV降低仅仅是正常情况的减弱或缩小版本。另一种可能性是，HRV的潜在机制发生了根本性变化，导致RR间期的顺序发生改变。我们研究了25名新生儿重症监护病房患者的RR间期时间序列的有序性的性质和程度，这些患者具有不同的临床疾病严重程度和HRV。我们测量了显示不同程度HRV的RR间期时间序列的可预测性（预测间期与观测间期的偏差）和规律性（以近似熵衡量）。在去除了尺度效应的RR间期时间序列中，我们发现：1）显示正常HRV的记录比显示低HRV的记录具有更多的有序性；2）这种有序性的性质更像是频率在较大范围内的周期性过程（其对数 - 对数功率谱具有1/f分布的时间序列），而不是混沌过程（逻辑斯蒂映射）；3）随着HRV下降，有序性的性质没有太大变化。我们得出结论，新生儿RR间期时间序列是由频率在较大范围内的周期性过程所决定的，并且在患病期间当HRV较低时，有序性的程度较低。
The mechanism by which heart rate variability (HRV) changes during neonatal illness is not known. One possibility is that reduced HRV is merely a diminished or scaled-down version of normal. Another possibility is that there is a fundamental change in the mechanism underlying HRV, resulting in a change in the ordering of RR intervals. We investigated the nature and extents of order in RR interval time series from 25 Neonatal Intensive Care Unit patients with a spectrum of clinical illness severity and HRV. We measured predictability (deviation of predicted intervals from observed, and regularity (measured as approximate entropy) of RR interval time series showing differ ent degrees of HRV, In RR interval time series where the effects of scaling were removed, we found 1) records showing normal HRV had more order than those showing low HRV; 2) the nature of the order was more like that of a periodic process with frequencies over a large range (time series whose log-log power spectrum had a 1/f distribution) than that of chaotic one (logistic map); and 3) the nature of order did not change greatly as HRV fell. We conclude that neonatal RR interval time series are ordered by periodic processes with frequencies over a large range, and that the extent of order is less during illness when HRV is low.