Koyanagi T, Nakahara H, Nakano H
Department of Gynecology and Obstetrics, Faculty of Medicine, Kyushu University, Japan.
Front Med Biol Eng. 1989;1(3):229-36.
We devised a method using a matrix to condense the large scale of fetal heart rates (FHR) without altering their characteristics. This matrix was arranged by FHRs at one beat per minute (bpm) intervals in rows, beat-to-beat differences (DFHRs) at one bpm intervals in columns and probabilities in the corresponding elements, respectively. Three matrices were calculated for Groups I, II and III: from 22 fetuses at 18-24 weeks, from 27 at 28-32 weeks and from 66 at 37-41 weeks of gestation, respectively. It was evident that the FHRs within the cumulative probability of 0.98 moved at 138-170 bpm in Group I, through 126-170 bpm in Group II onto 124-170 bpm in Group III. DFHRs spread symmetrically around zero bpm of DFHR for the entire scope of FHR values, irrespective of the age of gestation. This method can also be used for assimilating FHR data for analytical quantitation.
我们设计了一种方法,使用矩阵来压缩大规模的胎儿心率(FHR),同时不改变其特征。该矩阵的行由每分钟一次心跳(bpm)间隔的FHR排列,列由每分钟一次bpm间隔的逐搏差异(DFHR)排列,相应元素中的概率也分别排列。分别为I组、II组和III组计算了三个矩阵:分别来自18 - 24周的22例胎儿、28 - 32周的27例胎儿和37 - 41周的66例胎儿。很明显,累积概率为0.98范围内的FHR在I组中为138 - 170 bpm,在II组中为126 - 170 bpm,在III组中为124 - 170 bpm。无论妊娠年龄如何,DFHR在整个FHR值范围内围绕DFHR的零bpm对称分布。该方法也可用于同化FHR数据以进行分析定量。