检验羊水板层小体预测胎肺成熟108例分析

目的：探讨检测羊水板层小体在预测胎儿肺成熟中的价值。方法：收集108份孕妇的羊水,经离心后检测板层小体数值,同时由新生儿科医生进行新生儿呼吸窘迫综合征（NRDS）评价。结果：羊水板层小体与孕周有明显的关系,随着孕周的增加,板层小体数逐渐增加,其发生NRDS的概率越小。结论：板层小体的检测可以成为预测胎儿肺成熟度的指标。羊水板层小体作为胎肺成熟度的筛查试验具有简单、快速、可靠的特点。     

改良法检测羊水板层小体在预测胎儿肺成熟度中的作用

目的探讨羊水板层小体计数在预测胎儿肺成熟度中的意义。方法利用血细胞计数仪检测147例孕妇非离心羊水标本板层小体数值,由新生儿科医生对新生儿进行呼吸窘迫综合征(RDS)评价,分析羊水板层小体计数与新生儿RDS的关系。结果判定胎儿肺成熟度的羊水板层小体的界值为45×103/μl,阳性预侧值83.3%,阴性预侧值100%,灵敏度为100%,特异度88.9%。结论非离心羊水板层小体计数可以作为临床预测胎儿肺成熟度的指标,操作简便、快速,适宜临床推广。     

羊水板层小体检测在预测胎肺成熟度中的应用

目的探讨羊水板层小体的数量检测在预测胎肺成熟度中的应用。方法选择2005年12月至2009年3月本院产科不同孕周的妊娠糖尿病患者192例,抽取羊水标本,使用血细胞计数仪检测羊水中板层小体的数量,确定其与胎肺成熟度的关系。结果 192例孕妇不同孕周板层小体的数量在(3~236)×109/L之间,孕34~35、36~37、38~39周板层小体数量与孕32~33周板层小体数量分别进行比较,经t检验,差异有统计学意义(P0.05);孕34~35、36~37、38~39周板层小体数量分别进行两两比较,经t检验,差异无统计学意义(P0.05)。在192例新生儿中有15例发生新生儿呼吸窘迫综合征(NRDS),发病率为7.81%。结论羊水板层小体检测是预测胎肺成熟度很好的初筛方法,简单易于操作,值得临床推广。     

快速测定胎肺成熟度的轻击试验

一种理想的测定胎肺成熟度的方法应是快速、简便,对成熟或未成熟胎肺具有较高的预测值。但目前尚未有人提出这种理想的试验方法。测定卵磷脂与鞘磷脂的比例(L/S)和磷脂分布图,是迄今检测胎肺表面活性物质的最好方法,但这些试验对胎肺未成熟预测值低,费时,花耗昂贵。本文介绍一种估计胎肺成熟度的新方法——轻击试验(Thtap test)。该试验快速,化费少,其准确性与磷脂分布图相当。     

正常胎儿呼吸羊水流超声频谱特征的临床研究

目的 探讨超声检测胎儿呼吸羊水流多普勒频谱特征的临床意义.方法 随机选择妊娠15～40周306例胎儿,应用超声检测胎儿外呼吸道的呼吸羊水流,获得频谱图及相关参数.结果 胎儿呼吸羊水流频谱分为4种类型,频谱类型与孕周有关,Ⅰ型频谱及呼出波时间/吸人波时间(Tout/Tin)比值在0.58±0.05是胎肺成熟的标志.结论 超声能有效地检测出胎儿呼吸羊水流的频谱,可以作为临床评估胎肺成熟度的有效方法.     

胎儿肺动脉血流指数与肺成熟度关系的临床研究

目的 探讨肺动脉阻力指数(RIPA)在胎儿肺成熟度预测中的临床价值.方法 随机选择正常妊娠310例胎儿及羊水泡沫试验结果和Apgar评分异常的40例胎儿,应用彩色多普勒检测每例胎儿的RIPA.结果 正常胎儿的RIPA随着孕龄的增加而逐渐减小,两者具有高度的相关性(r=-0.98,P＜0.001).正常胎儿中RIPA为0.82±0.02,明显低于异常组0.86±0.01(P＜0.001).结论 胎儿的RIPA在整个妊娠期中具有规律性变化,并且与胎肺成熟度有关,可以作为临床评估胎儿肺发育的有效方法.     

胎盘分级胎头双顶径和羊水超声显象预测胎儿成熟度价值的研究

通过377例妊娠晚期的胎盘分级，胎头双顶径（BPD）和羊水超声显象观测，并与羊水生化测定等相对比，对其预测胎儿成熟度的价值进行了研究。结果：（1）胎盘Ⅲ级随着孕龄的增加而持续增多，过期妊娠时达16％；（2）妊娠37周以上时BPD大于等于8．6cm,BPD大于等于8．7cm及羊水过少分别占98．6％，100％及100％；（3）胎盘Ⅲ级和BPD大于等于8．7cm时，L／S均大于等于2，新生儿体重皆大于等于2500克，无RDS，羊水过少常伴有胎儿过熟（75％）；（4）三者之间具有相关关系，可以相互印证。（5）B型超声预测胎儿成熟度和可信性与羊水生化测定等是相同的，作者认为，利用B型超声预测胎儿成熟度以37周以上妊娠价值大，胎盘Ⅲ级，BPD大地等于8．7cm应作为胎儿发育成熟的超声指标，羊水过少的超声诊断应成为临床终止妊娠的指征，B型超声可作替代羊水穿刺检查而预测胎儿成熟度的一种良好方法。     

两种检测羊水板层小体方法评价及其临床应用

目的评价分别使用血细胞分析仪(MEK-8222K)和手工方法(显微镜镜检)计数羊水板层小体的临床应用价值。方法使用血细胞分析仪(MEK-8222K)计数101例孕妇(孕周为37周以上)羊水中的板层小体并与显微镜下计数的结果进行比较。结果仪器分析法和手工计数法的检测结果高度一致。结论仪器分析法是羊水板层小体计数的一种简单、快速、可靠的试验方法。     

超声多普勒参数主肺动脉加速时间与射血时间比值对妊娠糖尿病孕妇胎儿肺成熟度评估的价值研究

目的：研究超声多普勒参数主肺动脉加速时间与射血时间比值对妊娠糖尿病孕妇胎儿肺成熟度评估的价值。方法：选取2020年1月—2021年12月期间佛山市妇幼保健院收治的妊娠糖尿病37周后待产孕妇,共计500例,以分娩后胎儿肺成熟度情况,分为胎儿肺成熟组及胎儿肺非成熟组。对所有产妇均采用彩色多普勒超声诊断仪进行检查,期间记录胎儿主肺动脉中段的加速时间（AT）、射血时间（ET）,分析AT/ET值对新生儿肺成熟度的预测价值。结果：胎儿肺非成熟组AT/ET值低于胎儿肺成熟组（P <0.05）;ROC曲线显示,胎儿主肺动脉中段AT/ET预测新生儿肺成熟度的最佳截断值为0.218时,灵敏度为97.44%,特异度为99.76%,准确率为99.40%,AUC为0.908。通过一致性检验（Kappa检验）分析,AT/ET值预测妊娠糖尿病患者新生儿肺成熟度的效能较高（Kappa值=0.846,P <0.05）。结论：通过超声多普勒参数AT/ET值对妊娠糖尿病孕妇胎儿肺成熟度评估时,能够为临床提供有价值的信息,对新生儿肺成熟度评估有一定预测价值。     

人血清哇巴因UPLC-MS/MS检测方法的建立和方法比对

目的建立超高效液相色谱串联质谱(UPLC-MS/MS)检测人血清哇巴因的方法。方法采用高特异性的UPLC-MS/MS,以氘标记的哇巴因-d3作为内标。样本采用固相萃取(SPE)前处理方法,以反相色谱柱负离子模式及电喷雾电离源(ESI)检测血清哇巴因水平。对建立的方法进行方法学(基质效应、回收率、准确度、批内精密度、批间精密度及稳定性)验证。采用建立的UPLC-MS/MS方法检测20名体检健康者及40例高血压患者血清哇巴因水平,并与酶联免疫吸附试验(ELISA)进行比较。结果 UPLC-MS/MS检测血清哇巴因的标准曲线范围为0.02～5.0 ng/mL,最低定量检测限(LLOQ)为0.02ng/mL。采用ABN固相萃取小柱进行样本前处理的基质效应较小,且回收率较高,达85%。LLOQ和低值(0.06 ng/mL)、中值(0.6 ng/mL)、高值(4 ng/mL)质控品的准确度分别为108.0%、89.2%、101.0%、103.0%。3个水平质控品的批内变异系数(CV)分别为2.87%、1.95%、0.56%,批间CV分别为5.98%、1.90%、0.75%。样本室温过夜放置16 h及样本前处理后室温放置自动进样器48 h的偏差均15%。采用UPLC-MS/MS检测哇巴因,正常对照者及高血压患者血清中均未检测到哇巴因。采用ELISA测定血清哇巴因,高血压患者为0.096 ng/mL,正常对照者为0.062 ng/mL。UPLC-MS/MS检测5个水平(0.02、0.05、0.10、0.20、0.50 ng/mL)的哇巴因标准品,其测定结果与对应的哇巴因标准品浓度呈正相关,且线性较好(r20.99),准确度较高;而ELISA检测5个水平哇巴因标准品的结果均很接近(0.024 9～0.029 6 ng/mL)。结论建立了检测人血清哇巴因的UPLC-MS/MS方法,未检测到正常人及高血压患者的血清哇巴因。UPLC-MS/MS与ELISA检测血清哇巴因的结果存在较大差异。     

Sonographically detected free-floating particles in amniotic fluid predict a mature lecithin-sphingomyelin ratio

Amniocentesis for the determination of fetal lung maturity is associated with some morbidity, and so the prediction of a mature fetus by noninvasive means could be useful in managing certain high-risk patients. In the first portion of this study, 467 amniotic fluid specimens were classified into one of five groups based on the turbidity and particulate matter present. The mean lecithin: sphingomyelin (L/S) ratios and the proportion of mature L/S values increased with increasing turbidity of the amniotic fluid. In the second portion of this study, the presence of amniotic fluid free-floating particles (FFPs) detected by real-time ultrasound was correlated with fetal lung maturity. When FFPs were present, the L/S was uniformly mature, but when FFPs were absent, the L/S was mature in 74% of patients (P less than 0.01). Among the patients in whom the L/S ratios were mature, 39/110 were associated with positive FFPs (sensitivity = 35%). This preliminary study suggests that the presence of FFPs on real-time ultrasound could be used to confirm fetal lung maturity.     

The value of various investigations of amniotic fluid in the estimation of fetal maturity (author's transl)]

The amniotic fluid lecithin-spingomyelin (L/S) ratio, creatinine and uric acid concentrations, percentage of organe-stained fat cells and the foam test by Clements and coworkers have been compared in 82 samples of amniotic fluid from 66 patients. The specimens were obtained by transabdominal amniocentesis or amniotomy between the 24th and the 42nd week of pregnancy. The determination of the L/S ratio and the foam test seem to be reliable methods of estimating pulmonary surfactant and, hence, of predicting the respiratory distress syndrome (RDS) in the newborn infant. There was no RDS with an L/S ratio greater than 1.6 to 1.8. Positive foam tests also seem to be a valuable indicator of pulmonary maturity, no cases of RDS being found. However, false negative foam tests are not rare. The amniotic fluid concentration of creatinine correlated well with gestational age and birth weight. The determination of uric acid in the amniotic fluid is an unreliable test of fetal maturity on account of the large scatter. The percentage of orange-stained cells did not rise above 10% before the 39th week of pregnancy in most cases.     

Evaluation of two-dimensional cytometric lamellar body counts on the ADVIA 120 hematology system for estimation of fetal lung maturation

Background: We sought to determine if the ADVIA® 120 hematology system (Bayer HealthCare LLC, Diagnostics Division, Tarrytown, NY), which employs a unique two-dimensional cytometric analysis approach for platelet (PLT) counting, might also be useful for estimation of LB lamellar body counts in amniotic fluid. Methods: ADVIA® 120 LB counts were performed on 217 amniotic fluid specimens, 88 of which were obtained within 72 h of infant delivery. The ADVIA® 120 LB count (ADVIA LB count) results were compared with results from other FLM tests, including the TDx-FLM II (FLM II) test (Abbott Diagnostics, Abbott Park, IL) and the A₆₅₀ estimate of lamellar body density using the refractive-index-matched anomalous diffraction (RIMAD) technique. Results: Use of an ADVIA LB count referent value of ≥35,400/μl to indicate maturity, yielded sensitivity, specificity, PV_RDS and PV_maturity of 100%, 67.6%, 36.8% and 100%, respectively, in our study population (prevalence of RDS=15.9%). The clinical performance of the ADVIA LB count assay was compared to that of the FLM II and RIMAD assays by predictive value and receiver operating characteristic (ROC) curve analysis. Conclusions: These data suggest that the ADVIA® 120-derived LB counts on amniotic fluid can be useful in predicting fetal lung maturity.     

The evaluation of fetal lung maturity by amniotic fluid analysis.

The frequent necessity for termination of pregnancy before the spontaneous onset of labor requires that we be able to accurately predict fetal lung maturity. We have used amniotic fluid studies for evaluation of fetal lung maturity and have found that (1) a "fat" cell concentration of 30% or more, or (2) a creatinine concentration of 2.0 mg/100 ml or more, or (3) a lecithin:spingomyelin (L:S) ratio of 2.0 or greater all correlated well with fetal maturity. Since each of these studies is open to a variety of possible errors, the use of several different ones adds reliability to the estimation of fetal lung maturity.     

Improved fluorescence polarization assay for use in evaluating fetal lung maturity. III. Retrospective clinical evaluation and comparison with the lecithin/sphingomyelin ratio

We clinically evaluated, retrospectively, our improved fluorescence polarization assay for fetal lung maturity. The procedure requires 0.5 mL of amniotic fluid and a standard clinical laboratory fluorescence polarimeter (TDx Analyzer, Abbott Laboratories). We measured the L/S ratios for 93 freshly collected amniotic fluids, uncontaminated with blood or meconium, collected within three days of delivery. The fluids were stored frozen for eight to 32 months, then thawed and assayed for net fluorescence polarization. Fourteen of the infants developed respiratory distress syndrome; five, transient tachypnea of the newborn; and 74, no respiratory distress. The polarization assay and lecithin/sphingomyelin ratio had equivalent receiver operating characteristic curves, indicating no difference in their clinical performance. Although a prospective study with fresh amniotic fluid specimens will be necessary to establish a definitive reference range, the present study shows that this assay can be used to rapidly predict fetal lung maturity.     

Profile of phospholipids in amniotic fluid to assess fetal lung maturity in high-risk pregnancy

In assessing fetal lung maturity, an amniotic fluid profile, consisting of a total phospholipid (as phosphorus) (TPP) and total lecithin (LT) concentration, has been shown to yield a predictive accuracy of 97.5% with a false-negative rate of 2.4%. The LT had a range of specificity of 93% to 99%, whereas the one for the TPP was 88% to 96%. The cut-off values were 0.14 mg P/dl and 3.5 mg lecithin/dl of amniotic fluid. The analytical variables for laboratory tests for measuring amniotic fluid phospholipids led to the development of the quantitative tests used for this study. The proposed profile appears to offer the clinician an excellent means of judging how to manage the high-risk pregnancy.     

Prospective clinical evaluation of an improved fluorescence polarization assay for predicting fetal lung maturity

We performed a prospective clinical evaluation of our newly developed fluorescence polarization procedure to predict fetal lung maturity (Clin Chem 1986;32:248-54). Net fluorescence polarization was measured at 34 degrees C after a 6.5-min incubation of amniotic fluid with fluorophore. For the 26 cases of neonatal respiratory distress syndrome encountered in 196 deliveries, the net polarization exceeded 0.287 for 22 (85%) of these, and exceeded 0.260 for all 26. The specificity of the polarization assay equaled or exceeded the specificity of the lecithin/sphingomyelin ratio for all sensitivities greater than 70%. Neither assay was a good predictor of the clinical severity of respiratory distress. For a separate group of 21 amniotic fluid specimens clinically contaminated with blood or meconium, the discriminatory power of the polarization assay was decreased, but six of seven respiratory-distress cases still had polarization values greater than 0.260. We conclude that this fluorescence polarization assay is a better overall predictor of fetal lung maturity than is the lecithin/sphingomyelin ratio, and that polarization values less than 0.260 are associated with little risk of respiratory distress.     

Fetal lung maturity tests on the 10,000 X g pellet

Centrifugation has a profound effect on tests of fetal lung maturity performed on amniotic fluid. We have investigated the effect of a 700 X g centrifugal force for 10 min and a 10,000 X g force for 20 min on a battery of tests. While 91% of the OD650 was removed by the 10,000 X g centrifugal force, the supernatant fraction retained 34% and 38% of the L/S ratio and enzymatic lecithin respectively, when compared to the sample before centrifugation. Phosphatidylglycerol, when present in an amniotic fluid, was always absent from the 10,000 X g supernatant but present in the pellet formed by this centrifugal force. The pellet after 10,000 X g was unsuitable for OD650 and L/S ratio determinations but contained 63% of the enzymatic lecithin. When the pellet tests were subjected to a clinical trial, respiratory immaturity did not occur when phosphatidylglycerol was present or when the 10,000 X g pellet may be a useful means of detecting amniotic fluid surfactant and thus determining fetal lung maturity.     

Ultrasonically determined menstrual age as an indicator of fetal lung maturity

The usefulness of ultrasonically determined menstrual age as a predictor of fetal lung maturity has been evaluated in patients without fetal or maternal disease undergoing repeat cesarean section. The menstrual age of each fetus was determined at 18–32 wk using biparietal diameter (BPD) measurements and previously established BPD growth curves. Lung maturity prior to delivery was assessed by measuring the lecithin/sphingomyelin (L/S) in amniotic fluid. The menstrual age at the time of the amniocentesis was derived by extrapolation from the results of the first scan. When the Sabbagha Composite BPD growth curve was used for menstrual age determinations, the L/S was <2.0 in all cases before 34 wk, both <2.0 and ≥2.0 between 34 and 38 wk, and ≥2.0 in all but one case after 38 wk. This one case represents 1.2% of fetuses studied. These results suggest that in the absence of fetal and maternal disease, a menstrual age of 38 wk or older, based on an early BPD measurement and use of the Sabbagha Composite BPD growth curve, is indicative of lung maturity in most cases.     

Measurement of fetal surfactant production by fluorescence polarization of amniotic fluid in complicated pregnancies

The results are presented of fluorescence polarization as a method for measurement of surfactant production in 159 specimens of amniotic fluid collected from pregnant women with diabetes, hypertension, Rh immunization, premature rupture of membranes (for more than 48 h prior to delivery) and intrauterine growth retardation (IUGR). The predictability of the development of respiratory distress syndrome has been assessed by this assay. Its specificity, sensitivity and overall accuracy were similar to the lecithin/sphingomyelin (L/S) ratio. The influence of the conditions detailed on fetal lung maturation was determined, lung development being enhanced until near term by Rh immunization, rupture of membranes and hypertension with IUGR.