Study On Extraction Of Characteristic Parameters And Evaluation Method Of Fetal Condition Based On Cardiotocograph

Fetal monitoring is the main method of assessing the state of the fetus,and is the key technology to ensure that the fetus can grow stably during pregnancy until delivery.The most common method of fetal monitoring is fetal heart contraction monitoring(CTG),which is an electronic fetal monitoring technique.Analysis and assessment of fetal status based on monitoring parameters,manual analysis is heavy and is heavily dependent on personal experience.The clinical use of existing computer-aided analysis systems is unsatisfactory.To this end,this paper studies a new method of fetal status assessment based on fetal heart contraction curve,the specific research context is as follows:(1)Initially,this paper study the clinical significance and evaluation standard of fetal heart rate(FHR),uterine contraction(TOCO)and CTG.In addition,it not only elaborates the hazards,causes and monitoring methods of fetal hypoxia,but also specified the correlation between CTG and acidemia for demonstrating the feasibility of using CTG to access fetal hypoxia status automatically.Then,studying the extraction methods of some characteristic parameters such as fetal heart rate baseline,uterine contraction baseline and uterine contraction wave.(2)Build on the existing FHR baseline extraction algorithm.A new method for baseline adaptive threshold iterative deceleration zone identification is designed.Comparing the fetal heart rate curve of the baseline dynamically,locating the starting and ending points through the iterative threshold method in order to locate the deceleration zone accurately.At the same time,recording the amplitude and duration of fetal heart rate deceleration,which is more useful to analyze the FHR deceleration quantificationally.Setting and measuring the new quantitative indicator of fetal heart rate deceleration area(FHRDA)and using it to assess acidemia.Using integral method to calculate FHRDA by identifying the deceleration zone accurately.A total of439 cases of data were tested by Kruskal-Wallis single-factor nonparametric analysis of variance.The results showed that the FHRDA of the fetus is clinically statistically significant(P<0.05).According to the sensitivity experiments,the sensitivity of predicted fetal acidemia sensitivity is 53.6% and its predictive specificity is 80.1% by using FHRDA as a parameter.After classification with the standard of FHR baseline,predictive sensitivity of is 62.1% and the predictive specificity is 80.0%.Considering the consequences of differential analysis and sensitivity experiments,FHRDA can be used to comprehensively assess the magnitude,duration and frequency.There is a clinical correlation between FHRDA and neonatal pH,but FHRDA cannot be regarded as an independent parameter.A comprehensive consideration based on the FHR baseline is necessary.