正常妊娠及合并胎儿窘迫孕妇与新生儿不同分娩方式时血气及酸碱平衡变化

对４６例正常妊娠妇女（对照组）和４１例合并胎儿窘迫的足月妊娠妇女（窘迫组），于分娩时进行足背动脉和新生儿脐静脉、脐动脉血气分析；并将阴道分娩和剖宫产时酸碱平衡变化作了比较。结果：两组产妇动脉血除剩余碱（ＢＥ）偏低（＜－３ｍｍｏｌ／Ｌ）外，其余各值均在正常范围内，两组间各项指标比较，差异无显著性；两组脐静脉血气各项指标差异也无显著性；与对照组比较，窘迫组脐动脉血ｐＨ值、氧分压（ＰＯ＿２）、血氧饱和度（Ｏ＿２Ｓａｔ）均明显降低，二氧化碳分压（ＰＣＯ＿２）明显升高（Ｐ＜００５）。与剖宫产比较，两组阴道分娩产妇均显示有轻度代谢性酸中毒并轻度低氧血症，窘迫组胎儿酸中毒现象更为明显，新生儿出生时Ａｐｇａｒ评分≤７分的发生率也较高。提示：缩短产程对改善胎儿窘迫有重要意义。

Blood gas and acid-base equilibrium in normalpregnancy and pregnancy with fetal distress byvaginal dehvery or cesarean section

lood gas and acid-base assessment of matemaldorsalis pedis artery and umbilical artery and vein wascarried out immediately after delivery in 46 cases ofnormal term pregnancy and 41 cases of pregnancywith fetal distress(FD).Blood gas and acid-base equilibrium differences between vaginal delivery andcesarean section were studied.The resultS showed alow BE value(<-3mmol/L)in maternal artery ofboth groups,and that the other parameters were allwithin normal range, not being different between thenormal pregnancy and FD group.Blood gas assayingof umbilical veins of the 2 groups also showed no dif-ference. In comparison with the normal pregnantgroup,the FD group yielded significantly decreasedvalues of pH,PO_2 and O_2 Sat in umbilical artery butsignificantly increased PCO_2(P<0.05).Women ofboth groups delivered vaginally had milder metabolicacidosis and slighter hypoxia than those delivered bycesarean section. Marked fetal acidosis and low Apgarscore were more common ly seen in the FD group. These indicated that to delay labor to near term and toperform cesarean section for relieving fetal distress isadvisable.