Spong C Y, Ogundipe O A, Ross M G
Department of Obstetrics and Gynecology, Harbor-University of California, Los Angeles, Medical Center, Torrance 90509.
Am J Obstet Gynecol. 1994 Oct;171(4):931-5. doi: 10.1016/s0002-9378(94)70061-3.
Previous studies have demonstrated reduced perinatal morbidity in patients receiving amnioinfusion for meconium-stained amniotic fluid compared with control patients receiving no amnioinfusion. Because amnioinfusion for variable fetal heart rate decelerations has become accepted care, we sought to determine the benefit of prophylactic amnioinfusion for meconium compared with standard care, incorporating therapeutic amnioinfusion for variable decelerations.
Ninety-three term patients with moderate to heavy meconium and no variable fetal heart rate decelerations were randomized to immediate prophylactic amnioinfusion (600 ml saline solution bolus followed by 3 ml/min) or to standard care (including therapeutic amnioinfusion for variable decelerations developing later). All babies had DeLee suctioning on delivery of the head. Laryngeal cords were visualized and tracheal suctioning performed when meconium was seen below the cords. Statistical comparisons were performed using Student t test, Fisher's exact test, or chi 2 analysis.
There were no significant differences in the incidence of operative delivery, fetal distress, or meconium below the cords or in newborn Apgar scores and umbilical artery gas values between the amnioinfusion (n = 43) and control (n = 50) patients. There were four cases of meconium aspiration, three in the amnioinfusion group, one in the standard care group. The rate of endometritis-chorioamnionitis was higher (p = 0.3) in the amnioinfusion (16%) than in the control group (8%), although time from ruptured membranes to delivery (8.5 hours vs 7.3 hours) and duration of intrauterine monitoring (6.1 hours vs 5.3 hours) were not different.
Although amnioinfusion does dilute amniotic meconium, prophylactic amnioinfusion for meconium in the absence of variable decelerations remains controversial. Prophylactic amnioinfusion in term pregnancies did not improve perinatal outcome and increased the risk for chorioamnionitis-endometritis. Together with recent reports, the current data suggest that the benefit of amnioinfusion for meconium-stained amniotic fluid is a result of the alleviation of variable fetal heart rate decelerations rather than meconium dilution.
既往研究表明，与未接受羊膜腔灌注的对照患者相比，接受羊膜腔灌注治疗羊水胎粪污染的患者围产期发病率降低。由于针对可变胎心减速进行羊膜腔灌注已成为公认的治疗方法，我们试图确定与标准治疗相比，预防性羊膜腔灌注治疗胎粪污染的益处，标准治疗包括针对可变减速进行治疗性羊膜腔灌注。
93例足月、有中度至重度胎粪污染且无可变胎心减速的患者被随机分为立即进行预防性羊膜腔灌注组（静脉推注600ml生理盐水，随后以3ml/min的速度输注）或标准治疗组（包括对随后出现的可变减速进行治疗性羊膜腔灌注）。所有婴儿在胎头娩出时均进行德李氏吸引。当在声带下方看到胎粪时，观察声带并进行气管吸引。采用学生t检验、费舍尔精确检验或卡方分析进行统计学比较。
羊膜腔灌注组（n = 43）和对照组（n = 50）在手术分娩发生率、胎儿窘迫、声带下方胎粪污染情况或新生儿阿氏评分及脐动脉血气值方面无显著差异。有4例胎粪吸入病例，羊膜腔灌注组3例，标准治疗组1例。羊膜腔灌注组的子宫内膜炎 - 绒毛膜羊膜炎发生率（16%）高于对照组（8%）（p = 0.3），尽管从胎膜破裂到分娩的时间（8.5小时对7.3小时）和宫内监测时间（6.1小时对5.3小时）并无差异（原文此处有误，已修正）。
尽管羊膜腔灌注确实能稀释羊水胎粪，但在无可变减速的情况下对胎粪进行预防性羊膜腔灌注仍存在争议。足月妊娠时进行预防性羊膜腔灌注并不能改善围产期结局，反而增加了绒毛膜羊膜炎 - 子宫内膜炎的风险。结合近期报道，目前的数据表明，羊膜腔灌注治疗羊水胎粪污染的益处是由于缓解了可变胎心减速，而非胎粪稀释。
