第二产程胎心监护对胎儿预后的预测价值

Predictive value of fetal heart rate (FHR) monitoring during the second stage of labor for fetal prognosis.

目的探讨第二产程胎心监护对胎儿酸血症的预测价值及各不良胎心宫缩图(CTG)图形与不同类型胎儿酸中毒的关系。方法以216例在第二产程具有满意胎心监护图形的产妇为研究对象。胎儿娩出后,立即做脐血血气分析,记录胎儿结局,并追踪新生儿病率情况。结果①第二产程正常、可疑及病理CTG图形预测胎儿酸血症的敏感性分别为3.57%、10.72%和85.71%,特异性为57.45%、61.70%和80.85%,阳性预测值为1.23%、4.00%和40.00%,阴性预测值为80.00%、82.27%和97.44%,准确度为50.46%、55.09和81.48%。②晚期减速、延长减速在代谢性酸血症组的发生率明显高于呼吸性酸血症组及混合性酸血症组(P值分别为0.001、0.027);重度VD、重度心动过缓在混合性酸血症组明显高于代谢性酸血症及呼吸性酸血症组(P值分别为0.041、0.004);融合减速在呼吸性酸血症组明显高于混合性酸血症及代谢性酸血症组(P=0.006);基线变异消失在三组间无统计学差异(P=0.168)。结论①第二产程单用胎心监护识别胎儿酸中毒的能力非常有限,需结合其它监护手段进行综合判断,以避免不必要的手术干预。②晚期减速(LD)、延长减速(PD)与代谢性酸中毒有关;重度变异减速(VD)、重度心动过缓与混合性酸中毒有关;融合减速与呼吸性酸中毒有关。

Objective To investigate the predictive value of FHR monitoring during the second stage of labor for fetal acidemia and to investigate the relationship between pathological eardiotocogram （CTG） and different types of fetal acidosis. Methods 216 parturients with satisfactory FHR tracings during the second stage of labor were enrolled in the study. Umbilical blood gases were analyzed immediately after birth, fetal outcome and neonatal morbidity were recorded. Results ①The sensitivity of normal, marginal and pathological CTG patterns during the second stage of labor for predieton of fetal aeidemia was 3.57%, 10.72% and 85.71% , respectively; specificity was 57.45% , 61.70% and 80.85%, respeetively ; positive predictive value was 1.23%, 4.00% and 40.00%, respectively ; negative predictive value was 80.00%, 82.27% and 97. 44% , respectively; accuracy was 50.46%, 55.09% and 81.48%, respectively. ②The incidence of late deceleration （LD） and prolonged deceleration （PD） was significantly higher in the group of metabolic acidosis than that in the group of mixed acidosis and respiratory acidosis （ P = 0. 001, P = 0. 027, respectively）. The incidence of severe variable decelerations and severe bradyeardia was significantly higher in the group of mixed acidosis than that in the metabolic and respiratory acidosis （ P = 0.041, P = 0. 004, respectively）. The incidence of merging decelerations was significantly higher in the group of respiratory acidosis than that in the group of mixed and metabolic acidosis （ P = 0. 006 ）. No statistical differences were observed in the baseline rate of absent variability among the three groups （ P = 0.168 ）. Conclusion ①FHR monitoring alone was not efficient to detect fetal acidosis in the second stage of labor; other tests are required to confirm the diagnosis and to avoid unnecessary surgical intervention. ②LD and PD were associated with metabolic acidosis, severe variable decelerations and severe bradyeardia were associated with mixed acidosis and merging decelerations were associated with respiratory acidosis.