盐酸氨溴索与地塞米松在促胎肺成熟中的临床观察

目的:探讨产前应用盐酸氨溴索与地塞米松在促胎肺成熟中的疗效观察。方法:回顾性分析2005～2010年我院160例早产分娩的孕妇,随机分为两组,即治疗组和对照组,治疗组80例(产前28～34周应用盐酸氨溴索30mg/次,每天两次,5天),b组80例产前用地塞米松8mg/次,每天两次,连用3天,对比产后早产儿呼吸窘迫综合征的发病率。结果:盐酸氨溴索组降低早产儿呼吸窘迫综合征率明显优于地塞米松组,结论:产前应用盐酸氨溴索可以明显促胎肺成熟,降低早产儿呼吸窘迫综合征。提高早产儿存活率及生存质量。     

Accuracy of the lamellar body count in amniotic fluid contaminated by meconium

Objective: To determine whether meconium-contaminated amniotic fluid falsely elevates the lamellar body count in fetal lung maturity testing.

Methods: Thirty mothers undergoing amniocentesis for fetal lung maturity testing were prospectively consented. A 2?mL portion of the patient’s sample was mixed with a 10% meconium solution and the meconium-stained sample was then run in tandem with the patient’s sample used in clinical management. Pure meconium samples without amniotic fluid were also run through the cell counter for analysis.

Results: Following meconium contamination, the lamellar body count value increased in 67% of the cases, decreased in 23% and remained the same in 10%. There were 13 test results that had “immature” values in the uncontaminated patient management sample group and nine of these (69%) became elevated to a “mature” level (a false elevation) following the addition of meconium. All of the 10 pure liquid meconium samples devoid of amniotic fluid processed by the cell counter identified and quantified some particle the size of platelets.

Conclusions: The lamellar body count test result is not reliable in meconium-stained amniotic fluid specimens. There is some unknown particle found in meconium that is the size of platelets/lamellar bodies that can falsely elevate the test result. Currently, the only reliable fetal lung maturity test in meconium-stained amniotic fluid is the presence of phosphatidylglycerol.     

Lamellar bodies as a diagnostic test of fetal lung maturity.

OBJECTIVES: To determine the number of lamellar bodies in the amniotic fluid indicating fetal lung maturity and to define the effectiveness of a diagnostic test in a healthy pregnant population. METHODS: The study took place at the Hospital General de Zona #16 Centro Médico Nacional del Instituto Mexicano del Seguro Social. Torreón, Coahuila, México, where 264 pregnant women were followed-up from August 1997 to October 1998. The women presented in labor between 26 and 41 weeks of gestation. Amniotic fluid was obtained during cesarean section or from the vaginal pool and lamellar bodies were counted without prior centrifugation in Cell-Dyn 3000's channel for blood platelets. Results were masked for neonatologists. RESULTS: The prevalence of respiratory distress syndrome (RDS) was found to be 14.9%. At the 8200/microl threshold, sensitivity was: 15.4% (95% CI=5.9-30.5%), specificity: 99.6% (95% CI=97.5-99.9%), positive predictive value (PPV): 85.7, negative predictive value (NPV): 87.1, likelihood ratio for a negative test (LR-): 0.85, and likelihood ratio for a positive test (LR+): 85.7. At the 57 000/microl level, sensitivity was: 92.3% (95% CI=79.1-98.3%), specificity: 70.9% (64.4-76.7%), PPV: 35.6, NPV: 98.1, LR-: 0.11, and LR+: 3.17. When the cut-off point was 79000/microl, sensitivity was: 100.0%, specificity: 43.0% (95% CI=36.5-49.8%), PPV: 23.5, NPV: 100.0, LR+: 34.3, and LR-: less than 0.001. CONCLUSIONS: Counting lamellar bodies is a quick, readily available, and very effective test.     

Evaluation of fetal lung maturity in diamniotic twins

Objective: This study was undertaken to evaluate the correspondence in fetal lung development between diamniotic twins. Study Design: Lecithin/sphingomyelin ratios were determined for amniotic fluid specimens collected from each sac in 58 diamniotic twin pregnancies. Results: Overall, the lecithin/sphingomyelin ratios of twin A and twin B and those of the larger and smaller twins of each pair were closely correlated (r ≥ 0.83, P < .001). When stratified by gestational age, however, the percentage disparity in lecithin/sphingomyelin ratios between members of twin pairs was significantly greater at ≤32 weeks’ gestation (25%) than at >32 weeks’ gestation (15%, P = .027). An analysis of the lecithin/sphingomyelin ratios of twins with a large lecithin/sphingomyelin ratio disparity (≥20%) suggested that this disparity was a result of 1 twin having a lecithin/sphingomyelin ratio that was advanced for gestational age with respect to that of the co-twin. Disparities in lecithin/sphingomyelin ratio were not significantly affected by fetal sex or by discordance in size between the twins. Conclusion: At relatively early stages of diamniotic twin gestation (≤32 weeks’ gestation), lecithin/sphingomyelin ratios should be obtained for both amniotic sacs to ensure accurate assessment of fetal lung maturity in both twins. (Am J Obstet Gynecol 1999;180:1438-41.)     

Impact of timing of antenatal corticosteroid exposure on neonatal outcomes

Objective. To evaluate morbidities among neonates with a history of remote antenatal corticosteroid (ACS) exposure compared to those with recent exposure.

Study Design. This is a retrospective-cohort study of neonates born at 30–33 6/7 weeks gestational age. The primary outcome was newborn respiratory distress syndrome (RDS) defined by the persistent need for oxygen at 24 h of life. Maternal chart review established timing of ACS exposure. Data were stratified by the time interval of ACS administration to delivery: none or <48 h (Incomplete/Unexposed), 48 h to 7 days (Recent) and >7 days (Remote). Perinatal outcomes were compared between groups.

Resuts. Five hundred and twenty-four infants were included: 273 Incomplete/Unexposed, 120 Recent and 131 with Remote ACS exposure. RDS was significantly less frequent with Recent vs. Remote exposure (RR: 1.73 [1.01–3.02]p = 0.04). This finding persisted in a logistic regression model.

Conclusions. Infants delivering more than 1 week after ACS exposure have a higher frequency of RDS than those who deliver within 1 week.     

Assessment of fetal lung maturity by ultrasound: objective study using gray-scale histogram

Objective: To evaluate lung maturity using ultrasound (US), comparing the subjective and gray-scale histogram (GSH) techniques.

Methods: A total of 77 single pregnancies were evaluated and divided into the following two groups: 11 women of gestational age 28 to 35?+?6 weeks and 66 women?≥?36 weeks. The women underwent to emergency or planned cesarean section, according to fetal–maternal indications. The US was performed on the mean sagittal plane of the fetal torso, in order to observe the lung and hepatic areas. Fetal lung maturity was evaluated subjectively and through GSH. After delivery, the incidence of respiratory distress in the newborn was evaluated. The analyses were considered to be correct or incorrect, and comparisons were made using the McNemar test. In order to compare lung/hepatic echogenicity using GSH in groups with and without respiratory distress, the Student's t-test was used.

Results: The subjective evaluation identified 41 cases (53.2%) correctly and 36 (46.8%) incorrectly, while GSH found 58 (75.3%) correctly and 19 (24.7%) incorrectly (p?=?0.006). There was a significant difference in mean lung/hepatic echogenicity between the groups with and without respiratory distress (1.05 versus 1.26; p?=?0.002). In the group of 28 to 35?+?6 weeks, GSH presented sensitivity, specificity and accuracy in predicting respiratory distress of 61.9%, 89.1% and 81.6%, respectively.

Conclusion: The evaluation of fetal lung maturity through GSH was more effective than the subjective method in predicting respiratory distress among newborns.     

Assessment of neonatal adrenal size using high resolution 2D ultrasound and its correlation with birth demographics and clinical outcomes

Objective: Assessment of adrenal function in a sick neonate remains a challenge in spite of major advances in neonatal care. We used 2D ultrasound of adrenal glands to assess maturity of adrenal glands in extremely preterm infants and sick term and near term infants.

Study design: We collected demographics details of 99 mother–infants pairs (24–41 weeks) and obtained 2D ultrasound scans of adrenal glands in first week of life to measure adrenal volume, fetal zone size, and adrenal to kidney ratios. Relationship between adrenal measurements, antenatal factors, and postnatal outcomes were studied.

Results: We reported normative adrenal gland volume data during gestation from 80 appropriate for gestational age (AGA) infants. In a binary analysis, adrenal size was significantly related to gender, race, intrauterine growth restriction (IUGR), maternal chorioamnionitis, and maternal hypertension. Linear regression analysis showed that fetal zone is significantly related to not only gestational age but also chorioamnionitis and later development of intraventricular hemorrhage (IVH). Adrenal volume likewise is also related to gestational age, preeclampsia, and IVH.

Conclusions: Antenatal maternal factors and uterine environment affects adrenal growth and development thus postnatal high resolution 2D US scan of adrenal glands can provide useful information to predict outcomes. This information can complement hormone and adrenocorticotrophic hormone (ACTH) stimulation assays.     

Lecithin/sphingomyelin ratio and lamellar body count for fetal lung maturity: a meta-analysis

Objective

To determine and compare the diagnostic accuracy of the lecithin/sphingomyelin (L/S) ratio and lamellar body count (LBC) in the prediction of neonatal respiratory distress syndrome (RDS).

Study design

A systematic review was performed to identify studies comparing either the L/S ratio or the LBC with the occurrence of RDS published between January 1999 and February 2009. Two independent reviewers performed study selection and data extraction. For each study sensitivity and specificity were calculated. Summary receiver-operating characteristics (ROC) curves, assessing the diagnostic performance of both tests, were constructed. A subgroup analysis was performed to estimate the sensitivity and specificity of the various cut-off values.

Results

13 studies were included. The ROC curves of the collected data illustrate that the LBC and L/S ratio perform equally well in the prediction of RDS. Comparison of the two summary ROC curves of each test indicates that the diagnostic performance of LBC might even have a slight advantage over L/S ratio. Due to the wide cut-off range it was not possible to define specific cut-off values with the best accuracy.

Conclusion

We recommend replacing the L/S ratio as gold standard with the lamellar body count since the LBC is easy to perform, rapid, inexpensive, and available to all hospitals 24 h per day.     

The role of three-dimensional ultrasonography fetal lung volume measurement in the prediction of neonatal respiratory function outcome

Background: Respiratory distress is commonly encountered among premature babies immediately after birth resulting in significant neonatal morbidity or mortality.

Objectives: To evaluate the possible correlation between three dimensional fetal lung volumes (FLVs) and neonatal respiratory outcomes.

Study design: A cohort study included 100 pregnant women who participated in the study and were divided into two groups; group A (n: 50 – women pregnant ±34–37 weeks) and group B (n: 50 – women pregnant ±37⁺¹ to 40 weeks). A three dimensional measurement of the right fetal lung was made using virtual organ computer-aided analysis (VOCAL) software then correlated to neonatal respiratory functions namely Apgar score at birth and the occurrence of respiratory distress syndrome (RDS).

Results: In group A, FLV was negatively correlated with Apgar score and the occurrence of RDS. In group B, FLV showed no statistical correlation with Apgar score and the occurrence of RDS.

Conclusions: Three dimensional fetal lung volumes might be an accurate noninvasive predictor for the development of RDS among preterm fetuses.     

Sampling of amniotic fluid for LS ratio determination after rupture of membranes

After rupture of membranes (RM), amniotic fluid (AF) leaking from the external os can be collected by means of a sterile bladder catheter inserted into the vagina and connected to a plastic bag for determination of the $\text{L}\text{S}$ ratio. This study was designed to ascertain whether contamination of AF with cervical or vaginal mucus alters the $\text{L}\text{S}$ ratio determined by Gluck's method. 50 gravidas in term or preterm labor had their amniotic sac punctured by a long gauge-20 needle under amnioscopic sight. Two samples of AF were collected from the needle. After RM, a sterile plastic bladder catheter was placed in the vagina and connected to a plastic bag ordinarily used for urine collection. Two additional samples of AF were taken from the plastic bag. All 4 samples were marked with code numbers and submitted for $\text{L}\text{S}$ ratio determination. There were no significant differences in the $\text{L}\text{S}$ ratio between samples obtained by the two different techniques. It is concluded that sampling of AF by means of a vaginal catheter and a plastic bag does not alter the $\text{L}\text{S}$ ratio, and is therefore practicable for assessing fetal lung maturity after RM.     

Combined measurement of fetal lung volume and pulmonary artery resistance index is more accurate for prediction of neonatal respiratory distress syndrome in preterm fetuses: a pilot study

Objective: The objective of this study is to estimate optimal cut-off values for mean fetal lung volume (FLV) and pulmonary artery resistance index (PA-RI) as non-invasive measures to predict neonatal respiratory distress syndrome (RDS) in preterm fetuses.

Methods: A prospective study conducted at Ain Shams University Maternity Hospital, Egypt from May 2015 to July 2017: 80 eligible women diagnosed with preterm labor were recruited at 32–36 weeks’ gestation. Before delivery, three-dimensional ultrasound was used to estimate FLV using virtual organ computer-aided analysis (VOCAL), while PA-RI was measured by Doppler ultrasonography.

Results: A total of 80 women were examined. Thirty-seven (46%) of the newborns developed neonatal RDS. FLV was significantly lower in neonates who developed RDS (p?=?.04), whereas PARI was significantly higher in those who did not (p?=?.02). Cut-off values of FLV ≤27.2?cm³ and PARI ≥0.77 predicted the subsequent development of RDS. Combining both cut-offs generated a more sensitive and specific methodical approach for the prediction of RDS (sensitivity 100%, specificity 88.5%).

Conclusion: Measurement of FLV or PA-RI can predict RDS in preterm fetuses. Combined use of both measures bolstered their predictive significance.     

Obstetrical attitudes to glucocorticoid treatment for fetal lung maturation: time for a change?

A questionnaire survey was conducted among 1004 specialist and trainee obstetricians in the Netherlands and northern Belgium (i.e., Flanders). Glucocorticoids would be used by 85% in Belgium and 74% in the Netherlands, while 59% in both countries would combine them with betamimetic drugs in preterm labor. The more frequently respondents relied on glucocorticoids, the more likely they were to use them at more advanced gestational ages, to combine them with betamimetic drugs and to use that combination beyond 34 wk. Of those using glucocorticoids, only 11% would not do so after 32 wk, while 37% would use them after 34 wk and 5% even beyond 36 wk of gestation. Gestational age limits did not differ for glucocorticoids with or without betamimetic drugs. The findings indicate that the encouraging results of the early trials have lead to widespread inappropriate use of prenatal glucocorticoid therapy. Substantial overuse was more frequent than rejection of its use.     

促胎肺成熟方法及其疗效

有早产风险的孕妇产前应用糖皮质激素、大剂量盐酸氨溴索和肺表面活性物质制剂能促进胎儿肺表面活性物质的产生,可以降低早产儿生后新生儿呼吸窘迫综合征的发生率,对提高新生儿的存活率有重要作用。     

Role of chest ultrasound in neonatal lung disease: a review of current evidences

Among the common causes of neonatal admission to NICU, respiratory distress is one of the important causes. The neonatal respiratory distress is end result of various pulmonary and non-pulmonary causes. Differentiation of pulmonary causes of respiratory distress is important for the neonatologist as treatment differs with different etiologies. Conventionally, chest X-ray and sometimes CT scan have been used to identify the etiology of respiratory distress but these modalities have several limitations which make their use in NICU doubtful. In recent decades, there has been use of lung ultrasound (LUS) to identify and differentiate the etiologies of respiratory distress. The current available evidence show that LUS has good sensitivity and specificity to identify all the common causes of neonatal distress like respiratory distress syndrome, transient tachypnea of newborn, pneumothorax, and pneumonia. This review will cover the various uses of LUS in neonatal care with current available evidence.