Weitzner J S, Strassner H T, Rawlins R G, Mack S R, Anderson R A
Department of Obstetrics and Gynecology, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois.
Obstet Gynecol. 1990 Dec;76(6):1143-4.
The amount of meconium in amniotic fluid is subjectively estimated by visual inspection and classified as thin (light), moderate, or thick (heavy). This estimate may be important for assessing the neonatal risk of perinatal asphyxia and meconium aspiration syndrome. This study reports on the "meconium-crit," a simple, rapid, inexpensive, and reproducible method of quantifying meconium concentration in amniotic fluid. The purpose of the study was to determine the relationship between the meconium-crit and meconium concentration. Specimens were prepared by placing 3.0 g of fresh neonatal meconium into clear amniotic fluid and vortexing for 15 minutes to obtain a stock solution of 15.0 g meconium/100 mL amniotic fluid. Stock solutions were then diluted with clear amniotic fluid to obtain concentrations of 10.0, 7.5, 5.0, 3.0, and 1.5 g/100 mL. One-tenth milliliter of the amniotic fluid/meconium mixture was drawn into a standard hematocrit tube and centrifuged. The meconium-crit was then measured directly as with a hematocrit. Regression analysis indicated that meconium-crit values were linearly related to meconium concentration (r = 0.901-0.995). This method provides a reproducible means of quantifying meconium in amniotic fluid.
羊水胎粪量通过肉眼观察进行主观评估，并分为稀薄（浅色）、中等或浓稠（深色）。这种评估对于评估围产期窒息和胎粪吸入综合征的新生儿风险可能很重要。本研究报告了“胎粪临界值”，这是一种简单、快速、廉价且可重复的量化羊水中胎粪浓度的方法。该研究的目的是确定胎粪临界值与胎粪浓度之间的关系。通过将3.0克新鲜新生儿胎粪放入清澈的羊水中并涡旋15分钟来制备标本，以获得15.0克胎粪/100毫升羊水的储备溶液。然后用清澈的羊水稀释储备溶液，以获得10.0、7.5、5.0、3.0和1.5克/100毫升的浓度。将十分之一毫升羊水/胎粪混合物吸入标准血细胞比容管中并离心。然后像测量血细胞比容一样直接测量胎粪临界值。回归分析表明，胎粪临界值与胎粪浓度呈线性相关（r = 0.901 - 0.995）。该方法提供了一种可重复的量化羊水中胎粪的方法。
