Study On The Correlation Between The Perinatal Asphyxia And Prognosis Of Umbilical Arterial Blood Gas Analysis

Objective:To investigate the clinical value of umbilical arterial blood gas analysis for evaluation of perinatal asphyxia.Methods:(1)5916newborns which were deliveried in July2011to December2012at the First Affiliated Hospital of Kunming Medical University were enrolled. Using multiple logistic regression to explore risk factors of asphyxia. Comparing umbilical arterial blood gas value between fetal distress group and normal group.(2)Correlation analysis was used between series Apgar score and pH value of umbilical arterial blood gas. According to Apgar score, three groups were divided(Groupl:Apgar score0-3;Group2:Apgar score4-7;Group3:Apgar score0-3)Comparing pH、PaCO2、PaO2、HCO3-、 BE value of umbilical arterial blood gas among three groups.(3)Tracking prognosis of newborns transferred to NICU, retrospective statistical analysis including umbilical arterial blood gas value and Apgar score was used.Receiver operating characteristic(ROC)curve was used to get the optimal cutoff value of pH value for predicting neonatal hypoxic-ischemic injury.(4)Value of umbilical arterial blood gas was compared between perinatal asphyxia group and normal group.Result:(1)Eight risk factors of predicting perinatal asphyxia were cesarean delivery、 fetal intrauterine distress、preterm birth、abnormal presentation forceps midwifery、 prolonged labor、mother’s heart and lung diseases、the placenta problems, particularly fetal distress(OR=20.255,95%CI:9.420～43.533)was a strong relevant factor. The difference of pH、PaCO2、PaO2、HCO3-value of umbilical arterial blood gas between fetal distress group and normal full-term births group was statistically significant(P <0.05).(2)The pH value of umbilical arterial blood gas and1-minute Apgar score was related by Spearman correlation analysis(r=0.712,P=0.035).So was5-minute Apgar score(r=0.837,P=0.019).The difference of pH(F=3.728,P<0.0001)、PaCO2(F=2.917,P=0.037)and BE(F=3.896,P<0.0001)among three groups according to1-minute Apgar score was significant, but the difference of PaO2(F=1.601,P=0.203)、 HCO3-(F=0.289,P=0.749)among three groups was not significant; The difference of pH(F=3.873, P<0.0001)、PaCO2(F=2.9647,P=0.029)and BE(F=4.015,P<0.0001)among three groups according to5-minute Apgar score was significant, but the difference of PaO2(F=1.796,P=0.183)、HCO3-(F=0.324,P=0.619)among three groups was not significant.(3)The sensitivity、specifity、compliance rates of Apgar score were61.40%、96.88%、96.54%respectively; The three values of pH value were12.28%、99.18%、98.34%respectively; The three values of "Apgar score≤7+pH <7.0" were10.53%、99.96%、98.78%respectively for diagnosis of neonatal hypoxic ischemic myocardial injury. The sensitivity、specificity、compliance rates of Apgar score were23.53%、96.38%、96.17%respectively; The three values of pH value were100%、99.07%、98.78%respectively; The three values of "Apgar score≤7+pH <7.0" were0%、99.54%、99.26%respectively for diagnosis of neonatal necrotizing enterocolitis. The sensitivity、specificity、compliance rates of Apgar score were100%、0%、96.47%respectively; The three values of pH value were55.56%、99.15%、99.09%respectively; The three values of "Apgar score≤7+pH<7.0" were55.56%、99.63%、99.56%respectively for diagnosis of neonatal hypoxic-ischemic encephalopathy. The optimal cutoff of the pH value for predicting neonatal hypoxic-ischemic injury was7.025,its sensitivity and specificity was60.2%and94.2%;(4)The difference of pH、PaCO2、HCO3-、BE of perinatal between asphyxia group and normal group was significant.Conclusion:(1)Prenatal risk factors may predict perinatal asphyxia, the factor of fetal distress perinatal asphyxia may be more important than other factors.(2)Apgar score and umbilical arterial blood gas analysis are interrelated, each of them has diagnostic value for neonatal prognosis. The two factors may complement each other to elevate the prognosis value, but cannot replace each other.(3)The pH value of umbilical arterial blood gas is sensitive factor for neonatal hypoxic-ischemic injury,pH<7.025as the cutoff which has high diagnostic value.(4)The umbilical arterial blood gas analysis has important clinical value for the diagnosis of perinatal asphyxia.