Molcho J, Leiberman J R, Hagay Z, Hagay Y
J Biomed Eng. 1986 Apr;8(2):162-5. doi: 10.1016/0141-5425(86)90052-x.
When a fetus is acutely distressed, for example as a result of strangulation by the umbilical cord, the bowel content, meconium, may be passed into the amniotic fluid. Assessment of meconial contamination of the amniotic fluid is important in the management of late pregnancy. Fresh or increasing meconium content is an indication for urgent delivery. 'Old' meconium is usually distinguished from 'new' by visual inspection of the stained amniotic fluid; a more objective method could have advantages. We consider the effects of meconium staining of amniotic fluid on the spectrophotometric properties of the liquor. The absorption spectra of meconial amniotic fluids reveal an excess absorption band, centred around 410 nm. Quantification of the band height is proposed and it is shown that the height is linearly related to meconium concentration, with a proportionality factor, or sensitivity, of 0.046 +/- 0.009 (mean +/- s.d.) proportionality factor, or sensitivity, of 0.046 +/- 0.009 (mean +/- s.d.) optical density (OD) units per g l-1. This sensitivity factor may be used to estimate meconium concentration in samples of amniotic fluid.
当胎儿出现急性窘迫时，例如由于脐带受压，肠道内容物胎粪可能会排入羊水。评估羊水的胎粪污染情况在晚期妊娠管理中很重要。新鲜或增多的胎粪含量是紧急分娩的指征。通常通过对染色羊水进行目视检查来区分“陈旧”胎粪和“新鲜”胎粪；一种更客观的方法可能会有优势。我们研究了羊水胎粪染色对羊水分光光度特性的影响。胎粪污染羊水的吸收光谱显示在410nm左右有一个额外的吸收带。我们提出了对该吸收带高度进行定量的方法，结果表明其高度与胎粪浓度呈线性相关，比例系数（或灵敏度）为0.046±0.009（平均值±标准差）光密度（OD）单位每克升-1。这个灵敏度因子可用于估计羊水样本中的胎粪浓度。
