产程中胎儿血氧饱和度监测的临床研究

目的:研究产程中监测胎儿血氧饱和度(FSaO2)诊断胎儿窘迫的准确性及安全性,以及联合应用胎心电子外监护监测胎儿的合理途径。方法:对108例产妇在第一产程活跃期及第二产程中同时行胎心监护和胎儿血氧饱和度监测,动态观察胎儿血氧饱和度的变化,确定诊断胎儿窘迫的标准,依据分娩后Apgar评分及脐血血气分析结果,验证监测方法的敏感性、特异性、阳性预期值、阴性预期值与准确率。结果:(1)以胎儿血氧饱和度≤30%作为诊断胎儿窘迫的标准,对脐动脉血pH≤7.15预测的敏感性91.6%,特异性97.9%,阳性预期值84.6%,阴性预期值98.9%;(2)胎儿血氧饱和度≤30%持续5min以上预示胎儿有缺氧及酸中毒的可能;(3)胎心监护和胎儿血氧饱和度测定联合应用,可提高胎儿窘迫诊断的准确性。结论:胎儿血氧饱和度监测是一种理想的内监护方法;产程中常规应用胎心电子外监护,发现异常时可进一步进行胎儿血氧饱和度监测,是理想的监测方法。

Clinical study of the surveilance of fetal oxygen saturation

Objective:To study the clinical efficiency and safety of fetal oxygen saturation(FSaO_2) monitoring in order to explore reasonable route of diagnosis of fetal acidosis by combining FSaO_2 monitoring system and electronic fetal monitoring.Methods:Continuous fetal oxygen saturation monitoring combining with external electronic fetal monitoring were used at 108 term fetuses during active phase of first stage and second stage of labor.The dynamic physiological distribution of the FSaO_2 was recorded.The two monitoring methods were validated with standard sensitivity,specificity,positive predictive value,negative predictive value and accuracy on the bases of Apgar score and cord artery blood gases analysis results.Results:(1)With a 30% cutoff,prediction of fetal acidosis using FSaO_2 monitoring system was more accurate than that using external electronic fetal monitoring.Standard sensitivity was 91.6%,specificity was 97.9%,positive predictive value was 84.6%,negative predictive value was 98.9% and accuracy was 97.2%.(2)When FSaO_2 ≤30% continued over five minutes,it would foretell the possibility of fetal acidosis.(3) It would enhance diagnostic rate of fetal distress by combining FSaO_2 monitoring system and electronic fetal monitoring.Conclusion:FSaO_2 monitoring is a good method of fetal distress diagnosis.When abnormal fetal heart rate pattern of electronic fetal monitoring are found during labor,FSaO_2 monitoring is recommended to confirm fetal acidosis.