脐血血气分析在新生儿预后评估中的意义及相关因素研究

目的探讨脐血血气分析与Apgar评分的相关性及脐血血气分析对新生儿预后的评估价值。方法检测541名新生儿的脐动脉血及生后1h桡动脉血的血气分析；同时收集相关临床资料（如胎龄、体质量、母婴病理情况、家族史、疾病的发生发展等情况），结合临床检验、检查，观察住院期间有无缺氧造成各器官损害的表现。结果本研究脐动脉血血气分析参数平均值为：酸碱度（pH值）7．21±0．10，二氧化碳分压（PCO，）（59±14）mmHg（1mmHg=0．133kPa），氧分压（P02）（14±8）mmHg，碳酸氢根（HCO3^-）（23．7±2．9）mmol／L，剩余碱（BE）（-4．1±3．8）mmoL／L，氧饱和度（Sp2）（15．0±14．6）％。有胎儿宫内窘迫、异常分娩史的新生儿脐血pH值较低，早产儿脐血pH值较足月儿高。1minApgar评分与脐血pH值及其他血气指标均有明显相关性，而5minApgar评分仅与脐动脉血PO2和SpO2相关。神经系统损害与脐血血气分析各指标均有相关性，肾、心、代谢方面的损害与脐血pH及PC02值相关，肺、消化、血液系统损害只与脐血pH值相关。联合脐血pH值〈7．20及Apgar评分≤7评估器官损害的发生率较单用其中一项指标高。结论脐血血气分析与1minApgar评分有明显相关性，脐血血气分析及Apgar评分对窒息相关的器官损害均具有诊断价值，但其敏感性及特异性不理想。综合脐血pH值及Apgar评分可以提高窒息相关器官损害的预测价值。

Significance of umbilical cord blood gas analysis in evaluating the prognosis of neonates and corre-lated factors

Objective To investigate neonatal asphyxia and prognosis. Methods the value of umbilical artery blood gas analysis on judging Four hundred and fifty-one newborn infants from October 2009 to November 2011 were chose. Blood gas analysis of umbilical artery at birth and radial artery at 1 hour after birth were accessed in all 541 cases; The arterial blood gas was rechecked if necessary. Clin-ical data including the gestational age, birth weight, maternal and neonatal conditions, family history, information of occurrence and development of diseases were recorded. The clinical manifestation and laboratory examination to determine the organ dysfunction due to pefinatal asphyxia was observed. Results The reference value of umbilical arterial blood gas analysis： pH 7.21 ± 0. 10, PCO2 （59 ± 13）mm Hg（1 mm Hg =0. 133 kPa）, PO2（14±8）mm Hg,HCO3^-（23.7 ±2.9） mmol/L, BE（ -4. 1 ± 3.8 ） mmol/L, SO2 （ 15.0 ± 14. 6 ） %. Correlation analysis of high risk factors and umbilical arterial pH indicated that neonates with fetal distress and perverse labor had a significantly lower pH value; preterm infants had a significantly higher pH value. Significant correlation was found between Apgar score at 1 minute after birth and all the parameters of umbilical arterial blood gas. No correlation was found be-tween Apgar score at 5 minute after birth and the parameters of umbilical arterial blood gas except PO2 and SO2. The analytic result indicated that there was correlation between nervous system impairment and all parameters of umbilical arterial blood gas. Impairment of kidney, heart and metabolism was correlated with umbilical arterial pH and PCO2 value. Impairment of lung, digestion and hematological system was only correlated with umbilical arterial pH value. Conclusions There was significant correlation between Apgar score at 1 minute after birth and the umbilical cord blood gas analysis. Both umbilical cord blood gas analysis and Apgar score have diagnostic value in assessing asphyxia-related organs dysfunction, but the sensitivity and specificity were unsatisfied. Combination of umbilical arterial pH value and Apgar score may elevate the predictive value.