Increased Risk of Meconium-Related Ileus in Extremely Premature Infants Exposed to Antenatal Magnesium Sulfate

Neuroprotective therapies in the NICU in preterm infants: present and future (Neonatal Neurocritical Care Series)

The survival of preterm infants has steadily improved thanks to advances in perinatal and neonatal intensive clinical care. The focus is now on finding ways to improve morbidities, especially neurological outcomes. Although antenatal steroids and magnesium for preterm infants have become routine therapies, studies have mainly demonstrated short-term benefits for antenatal steroid therapy but limited evidence for impact on long-term neurodevelopmental outcomes. Further advances in neuroprotective and neurorestorative therapies, improved neuromonitoring modalities to optimize recruitment in trials, and improved biomarkers to assess the response to treatment are essential. Among the most promising agents, multipotential stem cells, immunomodulation, and anti-inflammatory therapies can improve neural outcomes in preclinical studies and are the subject of considerable ongoing research. In the meantime, bundles of care protecting and nurturing the brain in the neonatal intensive care unit and beyond should be widely implemented in an effort to limit injury and promote neuroplasticity. IMPACT: With improved survival of preterm infants due to improved antenatal and neonatal care, our focus must now be to improve long-term neurological and neurodevelopmental outcomes. This review details the multifactorial pathogenesis of preterm brain injury and neuroprotective strategies in use at present, including antenatal care, seizure management and non-pharmacological NICU care. We discuss treatment strategies that are being evaluated as potential interventions to improve the neurodevelopmental outcomes of infants born prematurely.

Risk factors and epidemiology of spontaneous intestinal perforation among infants born at 22-24 weeks' gestational age

OBJECTIVE

To describe the epidemiology, risk factors, and timing of spontaneous intestinal perforation (SIP) among infants born at 22-24 weeks' gestational age (GA).

STUDY DESIGN

Observational cohort study among infants born at 22-24 weeks' GA in 446 neonatal intensive care units.

RESULTS

We identified 9712 infants, of whom 379 (3.9%) developed SIP. SIP incidence increased with decreasing GA (P < 0.001). Antenatal magnesium (odds ratio (OR) 1.42; 95% confidence interval (CI), 1.09-1.85), antenatal indomethacin (OR 1.40; 95% CI, 1.06-1.85), postnatal indomethacin (OR 1.61; 95% CI, 1.23-2.11), and postnatal hydrocortisone exposure (OR 2.02; 95% CI 1.50-2.73) were associated with SIP. Infants who lost 15-20% (OR 1.77; 95% CI, 1.28-2.44) or >20% (OR 2.04; 95% CI, 1.46-2.85) of birth weight had higher odds of SIP than infants with weight loss <10%.

CONCLUSIONS

Antenatal magnesium exposure, antenatal indomethacin exposure, postnatal hydrocortisone exposure, postnatal indomethacin exposure, and weight loss ≥15% were associated with SIP.

Antenatal Magnesium Sulfate Is Not Associated With Improved Long-Term Neurodevelopment and Growth in Very Low Birth Weight Infants

BACKGROUND

Though antenatal magnesium sulfate (MgSO4) is widely used for fetal neuroprotection, suspicions about the long-term neuroprotection of antenatal MgSO4 have been raised.

METHODS

We investigated short- and long-term outcomes of antenatal MgSO4 use for 468 infants weighing < 1,500 g with a gestational age of 24-31 weeks.

RESULTS

Short-term morbidities and the risk of developmental delay, hearing loss, and cerebral palsy at a corrected age of 18-24 months and 3 years of age did not decrease in the MgSO4 group (infants who were exposed to MgSO4 for any purpose) or neuroprotection group (infants who were exposed to MgSO4 for fetal neuroprotection) compared with the control group (infants who were not exposed to MgSO4). The z-scores of weight, height, and head circumference did not increase in the MgSO4 group or neuroprotection group compared with the control group.

CONCLUSION

Antenatal MgSO4 including MgSO4 for neuroprotection did not have beneficial effects on long-term neurodevelopmental and growth outcomes.

Antenatal Magnesium Sulfate and adverse gastrointestinal outcomes in Preterm infants-a systematic review and meta-analysis

INTRODUCTION

To evaluate the effect of antenatal magnesium sulfate (MgSO4) on mortality and morbidity outcomes related to the gastrointestinal system (GI) in preterm infants.

METHODS

Data sources: A systematic literature search was conducted in November 2022. PubMed, CINAHL Plus with Full Text (EBSCOhost), Embase (Elsevier), and CENTRAL (Ovid) were searched. There were 6695 references. After deduplication, 4332 remained. Ninety-nine full-text articles were assessed and forty four articles were included in the final analysis.

STUDY ELIGIBILITY CRITERIA

Randomized or quasi-randomized clinical trials and observational studies that evaluated at least one of the pre-specified outcomes were included. Preterm infants whose mothers were given antenatal MgSO4 were included and whose mothers did not receive antenatal MgSO4 were the comparators. The main outcomes and measures were: Necrotizing enterocolitis (NEC) (stage ≥ 2), surgical NEC, spontaneous intestinal perforation (SIP), feeding intolerance, time to reach full feeds, and GI-associated mortality.

STUDY APPRAISAL AND SYNTHESIS METHODS

A random-effects model meta-analysis was performed to yield pooled OR and its 95% CI for each outcome due to expected heterogeneity in the studies. The analysis for each predefined outcome was performed separately for adjusted and unadjusted comparisons. All included studies were assessed for methodological quality. The risk of bias was assessed using elements of the Cochrane Collaboration's tool 2.0 and the Newcastle-Ottawa Scale for randomized controlled trials (RCTs) and non-randomized studies (NRS), respectively. The study findings were reported as per PRISMA guidelines.

RESULTS

A total of thirty-eight NRS and six RCTs involving 51,466 preterm infants were included in the final analysis. There were no increased odds of stage ≥2 NEC, (NRS : n = 45,524, OR: 0.95; 95% CI: 0.84-1.08, I2- 5% & RCT's: n = 5205 OR: 1.00; 95% CI: 0.89-1.12, I2- 0%), SIP (n = 34,186, OR: 1.22, 95% CI: 0.94-1.58, I2-30%), feeding intolerance (n = 414, OR: 1.06, 95% CI: 0.64-1.76, I2-12%) in infants exposed to antenatal MgSO4. On the contrary, the incidence of surgical NEC was significantly lower in MgSO4 exposure infants (n = 29,506 OR:0.74; 95% CI: 0.62-0.90, ARR: 0.47%). Studies assessing the effect on GI-related mortality were limited to make any conceivable conclusion. The certainty of evidence (CoE) for all outcomes was adjudged as 'very low' as per GRADE.

CONCLUSION

Antenatal magnesium sulfate did not increase the incidence of gastrointestinal-related morbidities or mortality in preterm infants. With the current evidence concerns, regarding the adverse effects of MgSO4 administration leading to NEC/SIP or GI-related mortality in preterm infants should not be a hurdle in its routine use in antenatal mothers.

Antenatal magnesium sulphate and delayed passage of meconium: A multicentre study

INTRODUCTION

The published evidence on the association between magnesium sulphate (MgSO₄) and delayed passage of meconium (DPM) is contradictory.

OBJECTIVES

To determine whether there is an association between the administration of MgSO₄ to the mother and DPM in the neonate, and to analyse serum magnesium levels in neonates in relation to the cumulative dose of MgSO₄ administered to the mother.

POPULATION AND METHODS

Retrospective and prospective descriptive and analytical study conducted in patients delivered at or before 32 weeks of gestation in 2 tertiary care hospitals. Delayed passage of meconium was defined as failure to pass meconium within 48 h of birth and/or need for rectal stimulation on 2 or more occasions to pass stool and/or interval of at least 48 h between the first and second bowel movements.

RESULTS

The study included 283 patients (204 retrospectively and 79 prospectively), of who 152 (53.7%) experienced DPM. Delayed passage of meconium was not associated with antenatal MgSO₄ administration, the cumulative maternal MgSO4 dose or neonatal serum magnesium levels. Older gestational age (OR, 0.8; confidence interval [CI], 0.69-0.93; P = 0.003) was an independent protective factor against DPM, while the need for advanced resuscitation (OR, 2.24; CI 1.04-4.86; P = 0.04) was a risk factor for DPM.

CONCLUSION

The neonatal serum levels of magnesium reached with the doses of MgSO₄ administered to mothers were not associated with DPM. Lower gestational age and the need for advanced resuscitation were predictors associated with an increased risk of DPM.

Risk factors for postoperative ileus after cesarean delivery

BACKGROUND

Despite extensive data regarding risk factors for postoperative ileus in the general and colorectal surgery literature, few studies have identified risk factors specific to the obstetrical population.

OBJECTIVE

This study aimed to identify factors associated with postoperative ileus following cesarean delivery.

STUDY DESIGN

This retrospective case-control study identified women who underwent cesarean delivery at a single hospital between January 2000 and January 2020 and subsequently developed postoperative ileus. Cases were matched in a 1:2 ratio with controls who underwent cesarean delivery and did not develop postoperative ileus. They were matched by age (±1 year) and body mass index (±1 kg/m2). Demographics, common comorbidities, obstetrical history, and delivery characteristics were analyzed.

RESULTS

A total of 147 cases and 294 controls were identified. Cases and controls were similar in terms of parity, number of previous cesarean deliveries, labor preceding their cesarean delivery, incidence of chorioamnionitis, and presurgical diagnosis of hypothyroidism or chronic hypertension. Cases tended to have a diagnosis of preeclampsia (cases 23.1% vs controls 10.5%; P<.001) and were more likely to have been exposed to magnesium sulfate (cases 34.0% vs controls 15.0%; P<.001). Surgical considerations that were common in cases were exposure to general anesthesia (cases 37.4% vs controls 4.1%; P<.001), midline vertical skin incisions (cases 13.6% vs controls 1.4%; P<.001), classical hysterotomy (cases 8.8% vs controls 1.7%; P=.001), estimated blood loss >1000 mL (cases 44.4% vs controls 11.6%; P<.001), transfusion of blood products (cases 25.8% vs controls 2.0%; P<.001), and hysterectomy at the time of cesarean delivery (cases 6.1% vs controls 0.7%; P=.001). After a multivariable modeling using stepwise logistic regression of all variables found to be statistically significant, transfusion of blood products, estimated blood loss >1000 mL, and exposure to general anesthesia were the remaining surgical factors associated with the development of ileus. These variables reflect both the complexity and most likely the duration of surgery that was required, although we note that we did not have operative time as a variable to explore. Preeclampsia was also identified as a comorbidity linked to the development of ileus.

CONCLUSION

A diagnosis of preeclampsia, exposure to general anesthesia, estimated blood loss >1 L, and transfusion of blood products were identified as potential risk factors for postcesarean ileus.