A Comprehensive Case Report Emphasizing the Role of Caesarean Section, Antibiotic Prophylaxis, and Post-operative Care in Meconium-Stained Fetal Distress Syndrome.

Meconium-stained amniotic fluid (MSAF) presents a complex medical scenario with significant implications for maternal and neonatal health. This case report explores the intricacies surrounding MSAF, focusing on its diagnosis, treatment, and the associated meconium aspiration syndrome (MAS). The report emphasizes the critical role of antibiotic prophylaxis in lower segment cesarean sections (LSCS) in balancing infection prevention in the mother with neonatal considerations. Additionally, it highlights personalized pain management and post-operative care regimens, contributing to a comprehensive strategy for maternal and neonatal well-being. A 27-year-old primigravida (primi) underwent a cesarean section due to the presence of meconium in the amniotic fluid, indicating fetal distress. The report meticulously documents vital signs, laboratory findings, and the timeline of events. The case report underscores the importance of diagnosing and treating MAS, offering valuable insights into management strategies and their impact on maternal and neonatal health. This case report emphasizes the critical role of antibiotic prophylaxis in LSCS to prevent maternal infection while considering neonatal well-being. The personalized pain management approach and post-operative care regimens contribute significantly to a comprehensive strategy for maternal and neonatal well-being. The findings provide valuable insights into diagnosing and treating MAS, highlighting the importance of timely intervention in similar clinical scenarios.

An Evaluation of In Utero Polycyclic Aromatic Hydrocarbon Exposure on the Neonatal Meconium Microbiome.

INTRODUCTION: In utero exposure to environmental polycyclic aromatic hydrocarbon (PAH) is associated with neurodevelopmental impairments[1-8], prematurity[9-12] and low birthweight[9,13-15]. The gut microbiome serves as an intermediary between self and external environment; therefore, exploring the impact of PAH on microbiota may elucidate their role in disease. Here, we evaluated the effect of in utero PAH exposure on meconium microbiome. METHODS: We evaluated 49 mother-child dyads within Fair Start Birth Cohort with full term delivery and adequate meconium sampling. Prenatal PAH was measured using personal active samplers worn for 48 hours during third trimester. Post-processing, 35 samples with adequate biomass were evaluated for association between tertile of PAH exposure (high (H) vs low/medium (L/M)) and microbiome diversity. RESULTS: No significant differences were observed in alpha diversity metrics, Chao1 and Shannon index, between exposure groups for total PAH. However, alpha diversity metrics were negatively associated with log benzo[a]anthracene (BaA) and log chrysene (Chry) with high exposure, but positively associated with log benzo[a]pyrene (BaP) with low/medium exposure. After adjustment for birthweight and sex, alpha diversity metrics were negatively associated with log BaA, BaP, Chry, Indeno[1,2,3-cd]pyrene (IcdP) and total PAH with high exposure. Conversely, with low/medium exposure, alpha diversity metrics positively correlated with log BaP and benzo[b]fluoranthane (BbF). No significant difference in beta diversity was observed across groups using UniFrac, weighted UniFrac, or Bray-Curtis methods. Differential expression analysis showed differentially abundant taxa between exposure groups. CONCLUSION: Bacterial taxa were detectable in 35/49 (71%) meconium samples. Altered alpha diversity metrics and differentially abundant taxa between groups suggest in utero PAH exposure may impede early colonization. Sample size is limited, but these findings provide supporting evidence for wider scale research. Research on long-term impact of prenatal PAH exposure on childhood health outcomes is ongoing. Differential effects of specific PAHs need further evaluation.

Impact of highly effective modulator therapy on gastrointestinal symptoms and features in people with cystic fibrosis.

Highly effective modulator therapy (HEMT), particularly the triple combination elexacaftor-tezacaftor-ivacaftor (ETI), significantly improved clinical outcomes and quality of life in people with Cystic Fibrosis (pwCF). This review analyzes current knowledge on the impact of HEMTs on gastrointestinal (GI) symptoms and features in pwCF. A descriptive review of English literature until February 29, 2024, was conducted using medical databases. Observational studies and clinical trials addressing GI reflux disease (GERD), lower GI symptoms and pancreatic disease were considered. Studies report positive effects of HEMTs on pH levels and bicarbonate secretion as well as improvement on intestinal inflammation. HEMTs also demonstrated positive effects on GERD and lower GI symptoms or conditions CF related such as dysbiosis. Taking ETI during pregnancy could also allow resolution of meconium ileus in fetuses with CF. The best benefits were observed in pancreatic function, potentially delaying CF-related diabetes and recovering pancreatic function in some children on ETI. Larger trials, particularly in pediatric populations, need to confirm these findings and explore long-term effects.

Adverse obstetric outcomes in cases of meconium-stained amniotic fluid complicated with intrapartum fever.

PURPOSE: Meconium-stained amniotic fluid (MSAF) often signifies colonization of the amniotic sac by microorganisms. This study investigated additional adverse obstetric outcomes associated with MSAF in deliveries complicated by maternal intrapartum fever (IF). METHODS: This retrospective study included all singleton pregnancies from 2014 to 2020, with intrapartum maternal fever ≥ 38 °C during a trial of labor. In accordance with departmental protocol, all patients received intravenous antibiotic therapy consisting of ampicillin and gentamicin in the absence of allergies to these medications. Subsequent antibiotic therapy was adjusted based on the culture results. Antibiotic treatment was discontinued postpartum after 48 h without fever. Swab cultures were obtained immediately postpartum from both the maternal and fetal sides of the placenta. Maternal and fetal outcomes, along with positive placental cultures, were compared between participants with MSAF&IF and those with clear amniotic fluid &IF (control group). RESULTS: In comparison to the control group (n = 1089), the MSAF&IF group (n = 264) exhibited significantly higher rates of cesarean delivery (CD) (p = 0.001), CD due to non-reassuring fetal heart rate (p = 0.001), and cord pH ≤ 7.1 (p = 0.004). Positive swab cultures from the placental maternal and fetal sides were more prevalent among the MSAF&IF group (23.1% vs. 17.6%, p = 0.041 and 29.2% vs. 22.9%, p = 0.032, respectively). Placental cultures yielding gastrointestinal pathogens and extended spectrum beta-lactamase were notably more common in the MSAF&IF group compared to controls (p = 0.023). However, there was no significant difference between groups regarding the rate of group B streptococcus positive placental cultures. CONCLUSIONS: Women experiencing IF and MSAF during labor face an elevated risk of CD compared to those with IF alone. The presence of MSAF heightens the risk of positive placental cultures, particularly with gastrointestinal and extended spectrum beta-lactamase pathogens.

Meconium microbiota in naturally delivered canine puppies.

BACKGROUND: Microbial colonization during early life has a pivotal impact on the host health, shaping immune and metabolic functions, but little is known about timing and features of this process in dogs. The objectives of this study were to characterize the first step of intestinal microbiota development in naturally delivered canine puppies and to investigate its relationship with the maternal bacterial flora, using traditional culture and molecular analyses. Sixty puppies of two breeds, Appenzeller Cattle Dog (n = 3 dams) and Lagotto Romagnolo (n = 6), housed in the same breeding kennel, were included in the study. Swabs were collected in duplicate (for culture and for molecular analysis) from the dams' vagina and rectum at the end of parturition, from puppies' rectum, before maternal care, and from the environment (floor of the nursery and parturition box). RESULTS: 93.3% meconium samples showed bacterial growth, limited to a few colonies in 57.0% of cases. High growth was detected for Enterococcus faecalis, which was the most frequently isolated bacterium. The genus Enterococcus was one of the most represented in the dams' rectum and vagina (88.9% and 55.6%, respectively). The genera Staphylococcus, Enterococcus, Escherichia and Proteus were also often isolated in meconium but were usually present in maternal samples as well, together with ubiquitous bacteria (Acinetobacter, Psychrobacter). In the environmental samples, just a few bacterial species were found, all with low microbial load. Additionally, bacteria of the phyla Proteobacteria, Firmicutes, and Actinobacteria were identified in meconium through molecular analysis, confirming the culture results and the early colonization of the newborn gut. Maternal, meconium and environmental samples had similar alpha diversity, while beta-diversity showed differences among families (i.e. a dam and her litter), and association indexes revealed a significant correlation between family members and between sample origin, suggesting a strong contribution of the maternal flora to the initial seeding of the canine neonatal gut and a strong individual dam imprint. CONCLUSION: This study showed that the meconium of vaginally delivered puppies has its own microbiota immediately after birth, and that it is shaped by the dam, which gives a specific imprint to her litter.

Diuresis-led volume replacement strategy in extremely low birth weight infants.

AIM: In extremely low birth weight infants, fluid overload has been associated with bronchopulmonary dysplasia and death. Excessive weight loss may increase the risk of meconium obstruction and intestinal perforation. As these infants display oliguria followed by polyuria, we embarked on a diuresis-led volume replacement strategy as of January 2020. METHODS: This single-centre analysis presents data of infants <1000 g birth weight surviving for more than 3 days admitted 2017-2019 (n = 217, daily volume increase) versus 2020-2022 (n = 2022, diuresis-led volume replacement). RESULTS: The second cohort had lower gestational age (median [interquartile range]: 253/7 [243/7-264/7] vs. 263/7 [251/7-282/7] weeks), less antenatal steroids (58% vs. 69%), more indomethacin (66% vs. 47%) and higher initial diuresis (5.6 [4.9-6.8] vs. 4.8 [4.2-5.5] mL/kg/h) but did not differ by relative weight loss at Day 7 of life. Employing binary logistic regression with gestational age, antenatal steroids and indomethacin as covariates, the cohorts did not differ by rates of patent ductus arteriosus, abdominal surgery or severe retinopathy of prematurity, while there were significant declines in sepsis (from 32% to 19%), bronchopulmonary dysplasia (from 26% to 23%) and mortality (from 13% to 7%). CONCLUSION: Diuresis-led volume replacement appears to be safe and maybe beneficial.

Meconium Proteins Involved in Iron Metabolism.

The lack of specific biological materials and biomarkers limits our knowledge of the mechanisms underlying intrauterine regulation of iron supply to the fetus. Determining the meconium content of proteins commonly used in the laboratory to assess the transport, storage, and distribution of iron in the body may elucidate their roles in fetal development. Ferritin, transferrin, haptoglobin, ceruloplasmin, lactoferrin, myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL), and calprotectin were determined by ELISA in meconium samples obtained from 122 neonates. There were strong correlations between the meconium concentrations of haptoglobin, transferrin, and NGAL (p < 0.05). Meconium concentrations of ferritin were several-fold higher than the concentrations of the other proteins, with the exception of calprotectin whose concentration was approximately three-fold higher than that of ferritin. Meconium ceruloplasmin concentration significantly correlated with the concentrations of MPO, NGAL, lactoferrin, and calprotectin. Correlations between the meconium concentrations of haptoglobin, transferrin, and NGAL may reflect their collaborative involvement in the storage and transport of iron in the intrauterine environment in line with their recognized biological properties. High meconium concentrations of ferritin may provide information about the demand for iron and its utilization by the fetus. The associations between ceruloplasmin and neutrophil proteins may indicate the involvement of ceruloplasmin in the regulation of neutrophil activity in the intrauterine environment.

Determinants of meconium-stained amniotic fluid among laboring mother in Ethiopia, systematic review and meta-analysis.

Background: Meconium-stained amniotic fluid (MSAF) occurs during childbirth when the amniotic fluid carries traces of meconium, the initial stool passed by a newborn. Often signaling fetal distress, MSAF is linked to heightened risks for both the mother and the newborn. In Ethiopia, there is insufficient attention given to this condition. Despite varied study results indicating a considerable range in MSAF occurrences, there is an absence of a comprehensive national overview. Therefore, this systematic review and meta-analysis aim to evaluate the aggregated prevalence of meconium-stained amniotic fluid among laboring mothers and its influencing factors in Ethiopia, providing a consolidated understanding for healthcare strategies and policies. Method: Following PRISMA guidelines, a systematic review and meta-analysis were executed. Extensive literature searches were conducted on PubMed, Google Scholar, and African Online Journal databases. The pooled prevalence was estimated using a weighted inverse variance random effect model. Heterogeneity among studies was evaluated through Cochrane Q-test and I 2 statistics. To assess publication bias, a funnel plot and Egger's test were performed. The identification of factors associated with meconium-stained amniotic fluid among laboring mothers in Ethiopia was conducted using Stata v 18 software. Result: In total, 63 articles were initially identified, and ultimately, four articles were deemed suitable for inclusion in this review. The combined prevalence of meconium-stained amniotic fluid among laboring mothers in Ethiopia was determined to be 20% (95% CI: 14%-25%). Upon conducting subgroup analysis, it was revealed that the prevalence of meconium-stained amniotic fluid was highest in the Oromia region and lowest in Addis Ababa. Notably, pregnancies complicated by pregnancy-induced hypertension disorder showed a significant association with the presence of meconium-stained amniotic fluid, with an odds ratio of 6.21 (95% CI: 4.04-8.38). Conclusion: In conclusion, this review emphasizes the common occurrence of meconium-stained amniotic fluid (MSAF). Notably, it identifies a significant association between pregnancy complicated by hypertension and the presence of MSAF. This underscores the need for targeted interventions to reduce MSAF incidence and mitigate associated adverse outcomes in the Ethiopian. Systematic Review Registration: http://www.library.ucsf.edu/, (CRD42023491725).

Gut Dysbiosis in the First-Passed Meconium Microbiomes of Korean Preterm Infants Compared to Full-Term Neonates.

Since gestational age (GA) is an important factor influencing the presence of specific microbiomes, we aimed to characterize the core microbiomes of preterm infants compared to full-term (FT) infants. This study investigated the differences in microbiota composition between very preterm (VP), moderate-to-late preterm (MLP), and FT neonates by examining the core microbiomes of a large cohort of Korean neonates. Meconium samples from 310 neonates with a GA range of 22-40 weeks were collected, and 16S rRNA analyses were performed; 97 samples were obtained from the FT, 59 from the VP, and 154 from the MLP group. Firmicutes, Bacteroidetes, and Proteobacteria were the phylum-level core microbiomes. Infants born before 37 weeks showed a disruption in the core microbiomes. At the phylum level, the relative abundance of Bacteroidetes was positively (r = 0.177, p = 0.002) correlated with GA, while that of Proteobacteria was negatively (r = -0.116, p = 0.040) correlated with GA. At the genus level, the relative abundances of Bacteroides and Prevotella were positively correlated with GA (r = 0.157, p = 0.006; r = 0.160, p = 0.005). The meconium of preterm infants exhibited significantly lower α-diversities than that of FT infants. ß-diversities did not appear to differ between the groups. Overall, these findings underscore the importance of GA in shaping the early gut microbiome.

Use of N-Acetylcysteine in Preterm Neonates with Enteral Feeding Intolerance and Intestinal Obstruction: A Case Series and Review of the Literature.

(1) Background: The use of N-acetylcysteine (NAC) to relieve meconium obstruction of prematurity in the first days of life has been reported, with NAC reducing the viscosity of luminal contents by cleaving the disulfide bonds of mucoproteins. However, its use in this population should be further explored since it has been associated with hypernatremia and transient increase in transaminases and bilirubin. (2) Methods: In this retrospective study, we included neonates admitted because of enteral feeding intolerance and intestinal obstruction from 2019 to 2021 who received NAC as a rescue therapy before explorative laparotomy. (3) Results: We summarized the clinical presentation of six preterm neonates with enteral feeding intolerance and intestinal obstruction who received NAC as a rescue therapy. Four infants (66.7%) gradually improved without the need for explorative laparotomy, whereas two infants (33.3%) underwent the creation of an ileostomy. No cases of hypernatremia or hepatic derangement associated with NAC therapy were observed. (4) Conclusions: We described the use of NAC treatment by nasogastric tube and/or rectal enemas in preterm infants with enteral feeding intolerance and intestinal obstruction after a multidisciplinary assessment, but the limited sample size did not allow us to obtain definitive conclusions and further research is needed in this field, given the limited evidence about NAC treatment in preterm infants.

The international prevalence of prenatal alcohol use obtained via meconium biomarkers: A systematic literature review.

Fetal alcohol exposure is a growing public health concern. However, ascertaining its true extent remains challenging as maternal self-reports may lack validity. Increasingly, interest has turned to more objective measures of prenatal alcohol use (PAU) of which one, meconium, is recognized as a valuable tool. This review assesses both the international prevalence of PAU obtained using meconium biomarkers in general maternity populations and, when feasible, the level of agreement between meconium biomarkers and self-reported PAU. A systematic literature search for studies reporting the prevalence of PAU, as determined by meconium biomarker testing, was conducted using multiple electronic databases from 1990 to 2023. Seventeen studies were identified for inclusion and evaluated for methodological quality. Using fatty acid ethyl esters (FAEEs) meconium biomarkers, PAU prevalence varied from 2.4% to 44%. Rates based on EtG (ethyl glucuronide) analysis ranged from 0% to 16.3%, and EtS (ethyl sulfate) analysis from 7.8% to 16.7%. Studies were of moderate quality with high heterogeneity. Prevalence rates based on self-report data ranged from 0% to 46.4%. When reported, none of the reviewed studies identified agreement between meconium-based and self-report-based PAU prevalence rates. Using both self-reports to detect early pregnancy alcohol use, and meconium biomarkers to detect the occurrence of alcohol use later in pregnancy, may provide a more complete picture of PAU prevalence. Furthermore, research is warranted to develop stringent guidance on the ascertainment, storage, analysis, and reporting required in this field.

Investigations, management and outcome of neonates presenting with distal intestinal obstruction: challenging the need for contrast enemas.

PURPOSE: To characterise the investigations, management and ultimate diagnosis of neonates with distal intestinal obstruction. METHODS: Retrospective review of term (> 37 weeks) neonates with admission diagnosis of distal intestinal obstruction over 10 years (2012-2022). Patient pathways were identified and associations between presentations, response to treatments and outcome investigated. RESULTS: A total of 124 neonates were identified and all included. Initial management was colonic irrigation in 108, contrast enema in 4, and laparotomy in 12. Of those responding to irrigations none underwent contrast enema. Ultimately, 22 neonates proceeded to laparotomy. Overall, 106 had a suction rectal biopsy and 41 had genetic testing for cystic fibrosis. Final diagnosis was Hirschsprung disease (HD) in 67, meconium ileus with cystic fibrosis (CF) in 9, meconium plug syndrome in 19 (including 3 with CF), intestinal atresia in 10 and no formal diagnosis in 17. Median length of neonatal unit stay was 11 days (7-19). CONCLUSIONS: Initial management of neonates with distal bowel obstruction should be colonic irrigation since this is therapeutic in the majority and significantly reduces the need for contrast enema. These infants should all have suction rectal biopsy to investigate for HD unless another diagnosis is evident. If a meconium plug is passed, testing for CF is recommended. Evaluation and therapy are multimodal and time consuming, placing burden on resources and families.

Diagnosis and Management of Simple and Complicated Meconium Ileus in Cystic Fibrosis, a Systematic Review.

The early management of neonates with meconium ileus (MI) and cystic fibrosis (CF) is highly variable across countries and is not standardized. We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. The protocol was registered in PROSPERO (CRD42024522838). Studies from three providers of academic search engines were checked for inclusion criteria, using the following search terms: meconium ileus AND cystic fibrosis OR mucoviscidosis. Regarding the patient population studied, the inclusion criteria were defined using our predefined PICOT framework: studies on neonates with simple or complicated meconium which were confirmed to have cystic fibrosis and were conservatively managed or surgically treated. Results: A total of 566 publications from the last 10 years were verified by the authors of this review to find the most recent and relevant data, and only 8 met the inclusion criteria. Prenatally diagnosed meconium pseudocysts, bowel dilation, and ascites on ultrasound are predictors of neonatal surgery and risk factor for negative 12-month clinical outcomes in MI-CF newborns. For simple MI, conservative treatment with hypertonic solutions enemas can be effective in more than 25% of cases. If repeated enemas fail to disimpact the bowels, the Bishop-Koop stoma is a safe option. No comprehensive research has been conducted so far to determine the ideal surgical protocol for complicated MI. We only found three studies that reported the types of stomas performed and another study comparing the outcomes of patients depending on the surgical management; the conclusions are contradictory especially since the number of cases analyzed in each study was small. Between 18% and 38% of patients with complicated MI will require reoperation for various complications and the mortality rate varies between 0% and 8%. Conclusion: This study reveals a lack of strong data to support management decisions, unequivocally shows that the care of infants with MI is not standardized, and suggests a great need for international collaborative studies.

Fetal Appendiceal Perforation Masquerading as Meconium Peritonitis: A Report of a Rare Case.

Intrauterine appendicular perforation leading to meconium peritonitis is exceptionally rare, with few reported cases in the literature. This case underscores the diagnostic challenges and high mortality associated with neonatal appendicular perforation. Neonatal appendicitis and subsequent perforation are uncommon due to the funnel shape of the fetal appendix, which reduces susceptibility to luminal obstruction. While advances in neonatal care and diagnostic modalities have improved outcomes, challenges persist in timely diagnosis and management. We present the case of a preterm infant, one of dichorionic-diamniotic (DCDA) twins delivered via cesarean section, who developed gross abdominal distension and respiratory distress shortly after birth. Diagnostic abdominocentesis revealed meconium-stained fluid, prompting further investigation with imaging and subsequent exploratory laparotomy. Extensive adhesions and cecal perforation were observed, necessitating a cecostomy. Despite interventions, the infant's condition deteriorated, leading to a fatal outcome. Intrauterine appendicular perforation leading to meconium peritonitis is a rare and difficult-to-diagnose condition. Antenatal suspicion and early surgical intervention are crucial for improving outcomes. Factors contributing to neonatal appendicular perforation include ischemia, obstruction, and infective etiologies. Neonatal appendicular perforation is a rare but life-threatening condition requiring a high index of suspicion for prompt diagnosis and management. Advances in diagnostic tools and antenatal monitoring have contributed to improved outcomes, highlighting the importance of considering this diagnosis in cases of unexplained neonatal abdominal distension.

Meconium Aspiration Syndrome, Hypoxic-Ischemic Encephalopathy and Therapeutic Hypothermia-A Recipe for Severe Pulmonary Hypertension?

Hypoxic-ischemic encephalopathy (HIE) is the leading cause of mortality among term newborns globally. Infants born through meconium-stained amniotic fluid are at risk of developing meconium aspiration syndrome (MAS) and HIE. Simultaneous occurrence of MAS and HIE is a perilous combination for newborns due to the risk of persistent pulmonary hypertension of the newborn (PPHN). Moreover, therapeutic hypothermia (TH), which is the current standard of care for the management of HIE, may increase pulmonary vascular resistance (PVR) and worsen PPHN. Infants with MAS and HIE require close cardiorespiratory and hemodynamic monitoring for PPHN. Therapeutic strategies, including oxygen supplementation, ventilation, use of surfactant, inhaled nitric oxide and other pulmonary vasodilators, and systemic vasopressors, play a critical role in the management of PPHN in MAS, HIE, and TH. While TH reduces death or disability in infants with HIE, infants with MAS and HIE undergoing TH need close hemodynamic monitoring for PPHN.

MR Imaging of the Fetal Gastrointestinal Anomalies.

Fetal MR imaging has been shown to be a useful tool for the diagnosis of fetal gastro-intestinal pathologies. To recognize the various pathologies, it is, however, essential to know the normal MR imaging appearance of the fetal bowel at various gestational ages. By providing additional information to ultrasound in case of a fetal gastrointestinal anomaly, MR imaging helps to improve planning for the delivery, postnatal management, and improves parental counseling.

Long-Term Pulmonary and Neurodevelopmental Outcomes of Meconium Aspiration Syndrome Affected Infants: A Retrospective National Population-Based Study in Taiwan.

INTRODUCTION: Meconium aspiration syndrome (MAS) may cause severe pulmonary and neurologic injuries in affected infants after birth, leading to long-term adverse pulmonary or neurodevelopmental outcomes. METHODS: This retrospective population-based cohort study enrolled 1,554,069 mother-child pairs between 2004 and 2014. A total of 8,049 infants were in the MAS-affected group, whereas 1,546,020 were in the healthy control group. Children were followed up for at least 3 years. According to respiratory support, MAS was classified as mild, moderate, and severe. With the healthy control group as the reference, the associations between MAS severity and adverse pulmonary outcomes (hospital admission, intensive care unit (ICU) admission, length of hospital stay, or invasive ventilator support during admission related to pulmonary problem) or adverse neurodevelopmental outcomes (cerebral palsy, needs for rehabilitation, visual impairment, or hearing impairment) were accessed. RESULTS: MAS-affected infants had a higher risk of hospital and ICU admission and longer length of hospital stay, regardless of severity. Infants with severe MAS had a higher risk of invasive ventilator support during re-admission (odds ratio: 17.50, 95% confidence interval [CI]: 7.70-39.75, p < 0.001). Moderate (hazard ratio [HR]: 1.66, 95% CI: 1.30-2.13, p < 0.001) and severe (HR: 4.94, 95% CI: 4.94-7.11, p < 0.001) MAS groups had a higher risk of adverse neurodevelopmental outcome, and the statistical significance remained remarkable in severe MAS group after adjusting for covariates (adjusted HR: 2.28, 95% CI: 1.54-3.38, p < 0.001) Conclusions: Adverse pulmonary or neurodevelopmental outcomes could occur in MAS-affected infants at birth. Close monitoring and follow-up of MAS-affected infants are warranted.

Transitional Hemodynamics in Neonates Born Through Meconium-Stained Amniotic Fluid: A Prospective Observational Study.

Neonates born through meconium-stained amniotic fluid (MSAF) are at increased risk of altered cardiopulmonary transition at birth. There is a paucity of literature evaluating the transitional hemodynamics in these neonates. We aimed to evaluate transitional hemodynamics via echocardiography in neonates born through MSAF, compared to healthy neonates. The primary objective was to assess pulmonary vascular resistance using left pulmonary artery-velocity time integral (LPA-VTI). The secondary objectives were to assess other pulmonary vascular parameters and myocardial function. We enrolled 35 MSAF-born and 35 healthy neonates. Echocardiography was performed at 24 and 48 h of life by a pediatric cardiologist. Echocardiographic parameters were compared between MSAF-born and healthy neonates, and between MSAF-born neonates who developed meconium aspiration syndrome (MAS) and who did not (non-MAS). Among 35 MSAF-born neonates, 14 (40%) were non-vigorous, 18 (51%) required admission to neonatal intensive care unit, 8 (23%) developed MAS, 3 (9%) pulmonary hypertension and 1 (3%) air leak. On echocardiography, LPA-VTI (cm; mean ± SD) was significantly decreased at 24 and 48 h in MSAF-born neonates (14.38 ± 2.48; 15.55 ± 2.48), compared to healthy neonates (16.60 ± 2.14; 17.66 ± 2.71), respectively. Further, LPA-VTI was significantly reduced at 24 and 48 h among MAS (11.81 ± 3.0; 12.43 ± 2.5), compared to non-MAS neonates (15.15 ± 1.72; 16.48 ± 1.55), respectively. Other pulmonary vascular and myocardial function parameters were comparable between the two groups. Pulmonary adaptation was significantly delayed in neonates with MSAF, which was more pronounced in MAS neonates. Further studies should explore the utility of these parameters for early prediction of cardiorespiratory morbidities in this population.

Gestational Exposure to PM2.5 and Specific Constituents, Meconium Metabolites, and Neonatal Neurobehavioral Development: A Cohort Study.

Exposure to fine particulate matter (PM2.5) during pregnancy has been inversely associated with neonatal neurological development. However, the associations of exposure to specific PM2.5 constituents with neonatal neurological development remain unclear. We investigated these associations and examined the mediating role of meconium metabolites in a Chinese birth cohort consisting of 294 mother-infant pairs. Our results revealed that exposure to PM2.5 and its specific constituents (i.e., organic matter, black carbon, sulfate, nitrate, and ammonium) in the second trimester, but not in the first or third trimester, was inversely associated with the total neonatal behavioral neurological assessment (NBNA) scores. The PM2.5 constituent mixture in the second trimester was also inversely associated with NBNA scores, and sulfate was identified as the largest contributor. Furthermore, meconium metabolome analysis identified four metabolites, namely, threonine, lysine, leucine, and saccharopine, that were associated with both PM2.5 constituents and NBNA scores. Threonine was identified as an important mediator, accounting for a considerable proportion (14.53-15.33%) of the observed inverse associations. Our findings suggest that maternal exposure to PM2.5 and specific constituents may adversely affect neonatal behavioral development, in which meconium metabolites may play a mediating role.

Intratracheal instillation of budesonide suspension versus normal saline on oxidative stress in neonates with meconium aspiration syndrome.

BACKGROUND: Presently, the efficacy of neonatal resuscitation techniques via interventions such as oral, nasal, and endotracheal suction for preventing meconium aspiration syndrome (MAS) after delivery has not been satisfactory. OBJECTIVE: This study aimed to investigate the role of intratracheal instillation of budesonide on oxidative stress in MAS. METHODS: Sixty-two neonates with MAS admitted to Huai'an Maternity and Child Healthcare Hospital from January 2018 to June 2020 were divided into a study group (intratracheal instillation of 2 ml budesonide suspension; n = 31) and a control group (intratracheal instillation of 2 ml normal saline; n = 31). Collect data from two groups of patients and evaluate clinical outcomes, including oxygenation index (OI), as well as serum total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI) and 8-Isoprostane before treatment and 72h after admission. RESULTS: We found no statistical differences in mortality, complication rate, total oxygen inhalation time, OI before treatment and 72h after admission between the two groups of neonates with MAS, while the duration of invasive respiratory support in the study group was significantly shorter than in the control group. Also, serum TAC, TOS, OSI and 8-isoprostane levels were not statistically different before treatment between the two groups. After 72h of admission, OSI and 8-Isoprostane in neonates with MAS in the study group were much lower than those in the control group. TOS, OSI, 8-Isoprostane in the control group and 8-Isoprostane in the study group were significantly higher than those before treatment. As for TAC and TOS, no significant differences were observed between the two groups. CONCLUSION: Intratracheal instillation of budesonide was shown to alleviate oxidative stress and shorten invasive ventilation time in neonates with MAS.