Application Value Of Umbilical Artery Blood Gas Analysis Combined With Apgar Score In Evaluating Asphyxia Of Preterm Infants

Objective:To study the clinical value of umbilical artery blood gas analysis（UABGA）combined with Apgar score in evaluating asphyxia of preterm infants,and analyze the risk factors of organ injury in preterm infants with low Apgar score.Methods:In a retrospective study,premature infants with gestational age≥28weeks and Apgar score≤7 delivered in Gansu maternal and child health hospital from January 2019 to January 2021 were selected as the research objects（all subjects had been retained for UABGA）.They were divided into organ injury group and non organ injury group according to whether there was organ injury;According to the p H value,it is divided into normal p H group（p H≥7.2）,severe acidosis group（p H<7.0）and mild acidosis group（7.0≤p H<7.2）.The relationship between organ injury after asphyxia and different gestational age,body weight,degree of acidosis was analyzed.Pearson correlation was used to analyze the relationship between UABGA and organ injury in preterm infants with low Apgar score.The value of p H and BE in predicting organ injury in preterm infants with low Apgar score was analyzed by receiver operator characteristic curve and area under the curve.The risk factors of organ injury in preterm infants with low Apgar score were analyzed by multivariate logistic regression.Results:A total of 173 premature infants with low Apgar score were included in the study,including 82 cases in organ injury group and 91 cases in non organ injury group.（1）The p H and BE in the organ injury group were lower than those in the non organ injury group,7.0≤p H<7.2,p H<7.0,-162 and HCO₃^-were negatively correlated with organ injury in preterm infants with low Apgar score（r=-0.509、-0.506、-0.474、-0.236,all P<0.05）;PCO₂ was positively correlated with organ injury in preterm infants with low Apgar score（r=0.440,P<0.05）.（3）The incidence of multiple organ injury in preterm infants with low Apgar score was20.81%,and the incidence of single organ injury from high to low was lung（24.86%）,brain（18.50%）,heart（16.76%）,gastrointestinal tract（12.14%）,kidney（9.83%）and liver（7.51%）.（4）There were 30 cases in severe acidosis group,58 cases in mild acidosis group and 85 cases in normal group.The incidence of organ injury in severe acidosis group was higher than that in other groups.The incidence of organ injury in mild acidosis group was higher than that in normal group,the difference was statistically significant（P<0.05）.（5）At the gestational age of 28～31⁺⁶w,32～33⁺⁶w,34～36⁺⁶w and birth weight<1500g,1500～2500g,≥2500g subgroup analysis showed:the p H and BE values of organ injury group were lower than those of non-organ injury group（P<0.05）.With the increase of gestational age and weight,p H value and BE value of the group with organ injury tended to decrease.（6）p H<7.15 or BE≤-10mmol/l has higher value in evaluating organ injury in premature infants with low Apgar score.（7）Multivariate analysis showed that 7.0≤p H<7.2,p H<7.0 and5-minute Apgar score≤5 were independent risk factors for organ injury in preterm infants with low Apgar score（or=3.687,15.281 and 3.625,respectively,all P<0.05）.Conclusion:UABGA combined with Apgar score has high value in evaluating organ injury after asphyxia in preterm infants,and it can be used as one of the objective indexes to guide the diagnosis and evaluate the short-term prognosis of asphyxia in preterm infants.