The incidence, timing, and predisposing factors of germinal matrix and intraventricular hemorrhage (GMH/IVH) in preterm neonates

Neuroendoscopic Lavage and Third Ventriculostomy for the Treatment of Intraventricular Hemorrhage and Hydrocephalus in Neonates. A Prospective Study with 18 Months of Follow-Up

BACKGROUND

 Neonatal intraventricular hemorrhage (IVH) may evolve into posthemorrhagic hydrocephalus and cause neurodevelopmental impairment, becoming a common complication of premature infants, occurring in up to 40% of preterm infants weighing less than 1,500 g at birth. Around 10 to 15% of preterm infants develop severe (grades III-IV) IVH. These infants are at high risk of developing posthemorrhagic hydrocephalus. Neuroendoscopic lavage (NEL) is a suitable alternative for the management of this pathology. In this study, an endoscopic surgical approach directed toward the removal of intraventricular hematoma was evaluated for its safety and efficacy.

METHODS

 Between August 2016 and December 2019 (29 months), 14 neonates with posthemorrhagic hydrocephalus underwent NEL for removal of intraventricular blood by a single senior neurosurgeon. Complications such as reintervention and ventriculoperitoneal (VP) shunt placement were evaluated prospectively with an 18-month follow-up on average.

RESULTS

 In total, 14 neonates with IVH grades III and IV were prospectively recruited. Of these, six neonates did not need a VP shunt in the follow-up after neuroendoscopy (group 1), whereas eight neonates underwent a VP shunt placement (group 2). Nonsignificant difference between the groups was found concerning days after neuroendoscopy, clot extraction, third ventriculostomy, lamina terminalis fenestration, and septum pellucidum fenestration. In group 2, there was shunt dysfunction in five cases with shunt replacement in four cases.

CONCLUSION

 NEL is a feasible technique to remove intraventricular blood degradation products and residual hematoma in neonates suffering from posthemorrhagic hydrocephalus. In our series, endoscopic third ventriculostomy (ETV) + NEL could be effective in avoiding hydrocephalus after hemorrhage (no control group studied). Furthermore, patients without the necessity of VP-shunt had a better GMFCS in comparison with shunted patients.

The Possible Role of the Superior Sagittal Sinus in Regulating Cerebrospinal Fluid Dynamics among Preterm Infants: A Case Report and a Review of the Literature

We report the case of a preterm of 27 weeks of gestation who developed posthemorrhagic ventricular dilatation associated to a complete thrombosis of the superior sagittal sinus, for its peculiar interest in clarifying the physiology of the cerebrospinal fluid (CSF) dynamics. The exact CSF volume that must be removed to improve cerebral hemodynamics and outcomes in infants with posthemorrhagic ventricular dilatation is unknown. According to Volpe's studies, a volume of 10 to 15 mL/kg/die of body weight is commonly chosen. The subject we report needed an excessive CSF drainage (up to 32 mL/kg/d), in presence of a functioning external ventricular drain. We review the literature on the topic, and we postulate that the superior sagittal sinus may play an active role in the CSF dynamics of the immature brain (as it happens for the adult brain).

Navigating the Complexities of Intraventricular Hemorrhage in Preterm Infants: An Updated Review

Intraventricular hemorrhage (IVH) is a type of bleeding that occurs in the ventricular cavity of the brain. In this comprehensive study, we provide a summary of the pathogenesis, diagnosis, and treatment of intraventricular hemorrhage in premature infants. Preterm babies are at high risk of developing IVH because their germinal matrix is not fully developed, making their blood vessels more prone to rupture. However, that is not necessarily the case in all preterm babies as the inherent structure of the germinal matrix makes it more susceptible to hemorrhage. Incidences of IVH are discussed based on recent data which states that around 12,000 premature infants in the United States experience IVH each year. Although grades I and II make up the majority of IVH cases and are frequently asymptomatic, IVH remains a significant issue for premature infants in neonatal intensive care facilities worldwide. Grades I and II have been linked to mutations in the type IV procollagen gene, COL4A1, as well as prothrombin G20210A and factor V Leiden mutations. Intraventricular hemorrhage can be detected using brain imaging in the first seven to 14 days following delivery. This review also shines a light on reliable methods for identifying IVH in premature newborns like cranial ultrasound and magnetic resonance imaging along with the treatment of IVH which is primarily supportive and involves the management of intracranial pressure, the correction of coagulation abnormalities, and the prevention of seizures.

Assessment of role of cranial ultrasound (CUS) in the evaluation of high-risk preterm and term neonates

Background

Cranial ultrasonography (CUS) has become an important tool to depict normal brain anatomy and to detect the ischemic and hemorrhagic brain injury patterns in high-risk neonates. The present study aimed to assess the utility of CUS to diagnose the spectrum of brain injury patterns in high-risk preterm and term neonates admitted to the neonatal intensive care unit (NICU) and to find the association of CUS findings in various adverse antenatal and perinatal feto-maternal factors.

Results

Out of the 200 neonates, 76 (38%) neonates had abnormal CUS findings and 124 (62%) had a normal CUS. Germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) (28/76; 36.8 %) was the commonest abnormality with GMH (grade 1) in 14/76 (18.4%), grade 2 in 7 (9.2%), grade 3 in 5 (6.5%), and grade 4 in 2 (2.63%). The other findings observed were cerebral edema (14/76; 18.4%), thalamic hyperechogenicity (10/76; 13.1%), periventricular leukomalacia (PVL) (4/76; 5.2%), and congenital anomalies (8; 10.5%). Abnormal CUS findings had a statistically significant association with birth weight <2000 g, prematurity, Apgar score <7, and adverse peri-natal fetal and maternal factors (all p-values <0.05). Abnormal CUS findings had a statistically significant association with poor cry, poor activity, abnormal tone, and presence of cyanosis (all p-values <0.05).

Conclusion

In this cohort study of high-risk preterm and term infants GMH-IVH, cerebral edema, thalamic hyperechogenicity, PVL, and congenital malformations were the commonest lesions detected on CUS. Abnormal CUS findings were found to have a statistically significant association with various adverse peri-natal fetal and maternal factors.

Model for severe intracranial hemorrhage and role of early indomethacin in extreme preterm infants

BACKGROUND

To develop a model for prediction of severe intracranial hemorrhage (ICH) or death based on variables from the first 12 h of age and to compare mortality and morbidities with and without exposure to early indomethacin.

METHODS

This retrospective cohort study included extreme preterm (220/7-266/7 weeks) infants born at National Institute of Child Health and Human Development Neonatal Research Network sites. Primary outcome was a composite of severe ICH and/or death.

RESULTS

Of 4624 infants, 1827 received early indomethacin. Lower gestation, lack of antenatal steroids exposure, lower 1-min Apgar, male sex, and receipt of epinephrine were associated with severe ICH or death. Early indomethacin was associated with a lower risk of patent ductus arteriosus, bronchopulmonary dysplasia, and higher risk of spontaneous intestinal perforation.

CONCLUSIONS

A model for early prediction of severe ICH/death was developed and validated. Early indomethacin was associated with a lower risk of patent ductus arteriosus and bronchopulmonary dysplasia and a higher risk of spontaneous intestinal perforation.

CLINICAL TRIAL REGISTRATION

Not applicable.

IMPACT

Modern data on severe ICH and neonatal morbidities in relation to prophylactic indomethacin are scarce in the published literature. Prophylactic indomethacin was associated with a lower risk of patent ductus arteriosus and bronchopulmonary dysplasia and a higher risk of intestinal perforation. A risk estimator for severe intracranial hemorrhage/death was developed in a large cohort of extremely preterm infants. The risk estimator developed based on a large cohort of patients provides an estimate of severe intracranial bleeding for an individual infant.

Sodium supply from administered blood products was associated with severe intraventricular haemorrhage in extremely preterm infants

Aim

The aim of this study was to investigate the associations between sodium supply, fluid volume, sodium imbalances and severe intraventricular haemorrhage (IVH) in extremely preterm (EPT) infants.

Methods

We used data from the EXtremely PREterm infants in Sweden Study (EXPRESS) cohort consisting of all infants born at 22 to 26 gestational weeks from 2004 to 2007 and conducted a nested case–control study. For every infant with severe IVH (grade 3 or peri‐ventricular haemorrhagic infarction), one IVH‐free control infant with the birthday closest to the case infant and matched for hospital, sex, gestational age and birth weight was selected (n = 70 case–control pairs).

Results

Total sodium supply and fluid volume were higher in infants with severe IVH compared with controls [daily total sodium supply until postnatal Day 2: mean ± SD (mmol/kg/day): 5.49 ± 2.53 vs. 3.95 ± 1.91, p = 0.009]. These differences were accounted for by sodium and fluid from transfused blood products. High plasma sodium concentrations or large sodium fluctuations were not associated with severe IVH.

Conclusion

Our results suggest a relationship between sodium‐rich transfusions of blood products and severe IVH in EPT infants. It is unclear whether this is an effect of sodium load, volume load or some other transfusion‐related factor.

Development of an integrated risk scale for prediction of shunt placement after neonatal intraventricular hemorrhage

OBJECTIVE

Neonatal intraventricular hemorrhage (IVH) is a major cause of mortality and morbidity, particularly following premature birth. Even after the acute phase, posthemorrhagic hydrocephalus is a long-term complication, frequently requiring permanent ventriculoperitoneal shunt (VPS) placement. Currently, there are no risk classification methods integrating the constellation of clinical data to predict short- and long-term prognosis in neonatal IVH. To address this need, the authors developed a two-part machine learning approach for predicting short- and long-term outcomes after diagnosis of neonatal IVH. Integrating both maternal and neonatal characteristics, they developed a binary classifier to predict short-term mortality risk and a clinical scale to predict the long-term risk of VPS placement.

METHODS

Neonates with IVH were identified from the Optum Clinformatics Data Mart administrative claims database. Matched maternal and childbirth characteristics were obtained for all patients. The primary endpoints of interest were short-term (30 day) mortality and long-term VPS placement. Classification of short-term mortality risk was evaluated using 5 different machine learning approaches and the best-performing method was validated using a withheld validation subset. Prediction of long-term shunt risk was performed using a multivariable Cox regression model with stepwise variable selection, which was subsequently converted to an easily applied integer risk scale.

RESULTS

A total of 5926 neonates with IVH were identified. Most patients were born before 32 weeks' gestation (67.2%) and with low birth weight (81.2%). Empirical 30-day mortality risk was 10.9% across all IVH grades and highest among grade IV IVH (34.3%). Among the neonates who survived > 30 days, actuarial 12-month postdiagnosis risk of shunt placement was 5.4% across all IVH grades and 31.3% for grade IV IVH. The optimal short-term risk classifier was a random forest model achieving an area under the receiver operating characteristic curve of 0.882 with important predictors ranging from gestational age to diverse comorbid medical conditions. Selected features for long-term shunt risk stratification were IVH grade, respiratory distress syndrome, disseminated intravascular coagulation, and maternal preeclampsia or eclampsia. An integer risk scale, termed the Shunt Prediction After IVH in Neonates (SPAIN) scale, was developed from these 4 features, which, evaluated on withheld cases, demonstrated improved risk stratification compared with IVH grade alone (Harrell's concordance index 0.869 vs 0.852).

CONCLUSIONS

In a large cohort of neonates with IVH, the authors developed a two-pronged, integrated, risk classification approach to anticipate short-term mortality and long-term shunt risk. The application of such approaches may improve the prognostication of outcomes and identification of higher-risk individuals who warrant careful surveillance and early intervention.

Characterization of germinal matrix hemorrhage in extremely premature infants: recognition of posterior location and diagnostic pitfalls

BACKGROUND

Traditionally, descriptions of germinal matrix hemorrhage (GMH), derived from observations in preterm and very preterm infants, indicate its location at the caudothalamic grooves. However, before the germinal matrix begins to recede at approximately 28 weeks' gestational age (GA), it extends along the floor of the lateral ventricles far posterior to the caudothalamic grooves. Germinal matrix-intraventricular hemorrhage (GMH-IVH) can occur along any site from which the germinal matrix has not yet involuted. Therefore, as current advances in neonatology have allowed the routine survival of extremely preterm infants as young as 23 weeks' GA, postnatal GMH-IVH can occur in previously undescribed locations. Hemorrhage in the more posterior GMH on head ultrasound, if unrecognized, may lead to errors in diagnosis and mislocalization of this injury to the periventricular white matter or lateral walls of the lateral ventricles instead of to the subependyma, where it is in fact located.

OBJECTIVE

Our aim is to describe posterior GMH in extremely premature infants, including its characteristic imaging appearance and potential pitfalls in diagnosis.

MATERIALS AND METHODS

Over a 5-year period, all consecutive extremely preterm infants of 27 weeks' GA or less who developed GMH-IVH of any grade were included. A consecutive group of 100 very preterm infants of 31 weeks' GA with a GMH-IVH of any grade served as controls.

RESULTS

In 106 extremely preterm neonates (mean GA: 25 weeks, range: 23.1-26.6 weeks) with 212 potential lateral ventricular germinal matrix bleeding sites, 159 sites had bleeds. In 70/159 (44%), the GMH-IVH was located posterior to the caudothalamic grooves and the foramina of Monro, 52 (32.7%) were both anterior and posterior and 21 (13.2%) were exclusively anterior. In 16 ventricles with intraventricular hemorrhage, an origin site in the germinal matrix could not be determined. In the control population of very preterm infants, all hemorrhages were at the anterior caudothalamic grooves and 95% were grade I.

CONCLUSION

Unlike the older very preterm and moderately preterm infants that form the basis of our GMH-IVH description and classification, the extremely preterm infants now routinely surviving have a more fetal pattern of germinal matrix distribution, which is reflected in a different distribution and size of germinal matrix injury. We report the postnatal occurrence of subependymal GMH-IVH in extremely preterm infants in these more primitive, posterior locations, its potential imaging pitfalls and sonographic findings.

Adenosine Blood Level: A Biomarker of White Matter Damage in Very Low Birth Weight Infants

BACKGROUND

Very low birth weight infants are at risk of developing periventricular white matter lesions. We previously reported high blood adenosine levels in premature infants and infants with low birth weight. We asked whether blood adenosine levels could be related to the vulnerability of the maturing white matter to develop lesions. The present study aims at finding a biomarker for the early detection of brain white matter lesions that can profoundly influence the neurodevelopmental outcome, whose pathophysiology is still unclear.

METHODS

Dried blood spots were prospectively collected for the newborn screening program and adenosine concentration measurements. Fifty-six newborns who tested four times for blood adenosine concentration (at days 3, 15, 30, and 40 post-birth) were included in the program. All infants underwent brain MRI at term equivalent age. Neurodevelopmental outcomes were studied with Griffiths Mental Development Scales (GMDS) at 12 ± 2 months corrected age.

RESULTS

Blood adenosine concentration increased over time from a median of 0.75 μM at Day 3 to 1.46 μM at Day 40. Adenosine blood concentration >1.58 μM at Day 15 was significantly associated with brain white matter lesions at MRI (OR (95 % CI) of 50.0 (3.6-688.3), p-value < 0.001). A moderate negative correlation between adenosine at 15 days of life and GMDS at 12 ± 2 months corrected age was found.

CONCLUSION

These findings suggest a potential role for blood adenosine concentration as a biomarker of creberal white matter lesions in very low birth weight infants.

Germinal Matrix-Intraventricular Hemorrhage: A Tale of Preterm Infants

Germinal matrix-intraventricular hemorrhage (GM-IVH) is a common intracranial complication in preterm infants, especially those born before 32 weeks of gestation and very-low-birth-weight infants. Hemorrhage originates in the fragile capillary network of the subependymal germinal matrix of the developing brain and may disrupt the ependymal lining and progress into the lateral cerebral ventricle. GM-IVH is associated with increased mortality and abnormal neurodevelopmental outcomes such as posthemorrhagic hydrocephalus, cerebral palsy, epilepsy, severe cognitive impairment, and visual and hearing impairment. Most affected neonates are asymptomatic, and thus, diagnosis is usually made using real-time transfontanellar ultrasound. The present review provides a synopsis of the pathogenesis, grading, incidence, risk factors, and diagnosis of GM-IVH in preterm neonates. We explore brief literature related to outcomes, management interventions, and pharmacological and nonpharmacological prevention strategies for GM-IVH and posthemorrhagic hydrocephalus.

Lessons learned from proteome analysis of perinatal neurovascular pathologies

INTRODUCTION

Perinatal and pediatric diseases related to neurovascular disorders cause significant problems during life, affecting a population with a long life expectancy. Early diagnosis and assessment of the severity of these diseases are crucial to establish an appropriate neuroprotective treatment. Currently, physical examination, neuroimaging and clinical judgment are the main tools for diagnosis, although these tests have certain limitations. There is growing interest in the potential value of noninvasive biomarkers that can be used to monitor child patients at risk of brain damage, allowing accurate, and reproducible measurements.

AREAS COVERED

This review describes potential biomarkers for the diagnosis of perinatal neurovascular diseases and discusses the possibilities they open for the classification and treatment of neonatal neurovascular diseases.

EXPERT OPINION

Although high rates of ischemic and hemorrhagic stroke exist in pediatric populations, most studies have focused on biomarkers of hypoxic-ischemic encephalopathy. Inflammatory and neuronal biomarkers such as S-100B and GFAP, in combination with others yet to be discovered, could be considered as part of multiplex panels to diagnose these diseases and potentially for monitoring response to treatments. Ideally, noninvasive biofluids would be the best source for evaluating these biomarkers in proteomic assays in perinatal patients.

A systematic review on brain injury and altered brain development in moderate-late preterm infants

OBJECTIVES

To provide a systematic review of brain injury and altered brain development in moderate-late preterm (MLPT) infants as compared to very preterm and term infants.

STUDY DESIGN

A systematic search in five databases was performed in January 2020. Original research papers on incidence of brain injury and papers using quantitative data on brain development in MLPT infants were selected. The Johanna Briggs Institute 'Critical Appraisal Checklist for Studies Reporting Prevalence Data' was used for quality appraisal. Data extraction included: imaging modality, incidences of brain injury, brain volumes, 2D-measurements and diffusivity values.

RESULTS

In total, 24 studies were eligible. Most studies had a moderate quality. Twenty studies reported on the incidence of brain injury in MLPT infants. The incidence of intraventricular hemorrhage (IVH) ranged from 0.0% to 23.5% and of white matter injury (WMI) from 0.5% to 10.8%. One study reported the incidence of arterial infarction (0.3%) and none of cerebellar hemorrhage. Eleven studies compared incidences of brain injury between MLPT infants and very preterm or term infants. Five studies reported signs of altered brain development in MLPT infants.

CONCLUSIONS

The incidences of IVH and WMI in MLPT infants varied widely between studies. Other abnormalities were sparsely reported. Evidence regarding a higher or lower incidence of brain injury in MLPT infants compared to very preterm or term infants is weak due to moderate methodological quality of reported studies. There is limited evidence suggesting a difference in brain development between MLPT and term infants.

Retrieval of germinal zone neural stem cells from the cerebrospinal fluid of premature infants with intraventricular hemorrhage

Intraventricular hemorrhage is a common cause of morbidity and mortality in premature infants. The rupture of the germinal zone into the ventricles entails loss of neural stem cells and disturbs the normal cytoarchitecture of the region, compromising late neurogliogenesis. Here we demonstrate that neural stem cells can be easily and robustly isolated from the hemorrhagic cerebrospinal fluid obtained during therapeutic neuroendoscopic lavage in preterm infants with severe intraventricular hemorrhage. Our analyses demonstrate that these neural stem cells, although similar to human fetal cell lines, display distinctive hallmarks related to their regional and developmental origin in the germinal zone of the ventral forebrain, the ganglionic eminences that give rise to interneurons and oligodendrocytes. These cells can be expanded, cryopreserved, and differentiated in vitro and in vivo in the brain of nude mice and show no sign of tumoral transformation 6 months after transplantation. This novel class of neural stem cells poses no ethical concerns, as the fluid is usually discarded, and could be useful for the development of an autologous therapy for preterm infants, aiming to restore late neurogliogenesis and attenuate neurocognitive deficits. Furthermore, these cells represent a valuable tool for the study of the final stages of human brain development and germinal zone biology.

Neuroimaging findings associated with the fetal inflammatory response syndrome

The fetal inflammatory response syndrome (FIRS) is a condition whereby the fetus mounts an inflammatory response to intrauterine infection/inflammation. Clinical consequences include preterm premature rupture of membranes (PPROM), spontaneous preterm delivery, neonatal sepsis, bronchopulmonary dysplasia, and brain and other organ injury. Mechanisms leading to brain injury in FIRS have been investigated in animal and human studies. We review the neuroimaging findings of brain injury in FIRS, which overlap those of hypoxic-ischemic injury, and clinical correlation is necessary for a correct diagnosis. FIRS should be considered the primary diagnosis when neuroimaging findings such as periventricular leukomalacia are identified in preterm children born as a consequence of PPROM and spontaneous preterm labor. Additionally, FIRS should be considered in term infants who do not have the most common features of HIE (e.g. a sentinel event). Systematic histopathologic examination of the placenta and umbilical cord and/or detection of characteristic inflammatory markers in such cases are needed to establish the correct diagnosis.

Functional outcomes at 2 years of age following treatment for posthemorrhagic hydrocephalus of prematurity: what do we know at the time of consult?

OBJECTIVE

Posthemorrhagic hydrocephalus of prematurity remains a significant problem in preterm infants. In the literature, there is a scarcity of data on the early disease process, when neurosurgeons are typically consulted for recommendations on treatment. Here, the authors sought to evaluate functional outcomes in premature infants at 2 years of age following treatment for posthemorrhagic hydrocephalus. Their goal was to determine the relationship between factors identifiable at the time of the initial neurosurgical consult and outcomes of patients when they are 2 years of age.

METHODS

The authors performed a retrospective chart review of premature infants treated for intraventricular hemorrhage (IVH) of prematurity (grade III and IV) between 2003 and 2014. Information from three time points (birth, first neurosurgical consult, and 2 years of age) was collected on each patient. Logistic regression analysis was performed to determine the association between variables known at the time of the first neurosurgical consult and each of the outcome variables.

RESULTS

One hundred thirty patients were selected for analysis. At 2 years of age, 16% of the patients had died, 88% had cerebral palsy/developmental delay (CP), 48% were nonverbal, 55% were nonambulatory, 33% had epilepsy, and 41% had visual impairment. In the logistic regression analysis, IVH grade was an independent predictor of CP (p = 0.004), which had an estimated probability of occurrence of 74% in grade III and 96% in grade IV. Sepsis at or before the time of consult was an independent predictor of visual impairment (p = 0.024), which had an estimated probability of 58%. IVH grade was an independent predictor of epilepsy (p = 0.026), which had an estimated probability of 18% in grade III and 43% in grade IV. The IVH grade was also an independent predictor of verbal function (p = 0.007), which had an estimated probability of 68% in grade III versus 41% in grade IV. A higher weeks gestational age (WGA) at birth was an independent predictor of the ability to ambulate (p = 0.0014), which had an estimated probability of 15% at 22 WGA and up to 98% at 36 WGA. The need for oscillating ventilation at consult was an independent predictor of death before 2 years of age (p = 0.001), which had an estimated probability of 42% in patients needing oscillating ventilation versus 13% in those who did not.

CONCLUSIONS

IVH grade was consistently an independent predictor of functional outcomes at 2 years. Gestational age at birth, sepsis, and the need for oscillating ventilation may also predict worse functional outcomes.

Harnessing region-specific neurovascular signaling to promote germinal matrix vessel maturation and hemorrhage prevention

Germinal matrix hemorrhage (GMH), affecting about 1 in 300 births, is a major perinatal disease with lifelong neurological consequences. Yet despite advances in neonatal medicine, there is no effective intervention. GMH is characterized by localized bleeding in the germinal matrix (GM), due to inherent vessel fragility unique to this developing brain region. Studies have shown that reduced TGFβ signaling contributes to this vascular immaturity. We have previously shown that a region-specific G-protein-coupled receptor pathway in GM neural progenitor cells regulates integrin β8, a limiting activator of pro-TGFβ. In this study, we use mice to test whether this regional pathway can be harnessed for GMH intervention. We first examined the endogenous dynamics of this pathway and found that it displays specific patterns of activation. We then investigated the functional effects of altering these dynamics by chemogenetics and found that there is a narrow developmental window during which this pathway is amenable to manipulation. Although high-level activity in this time window interferes with vessel growth, moderate enhancement promotes vessel maturation without compromising growth. Furthermore, we found that enhancing the activity of this pathway in a mouse model rescues all GMH phenotypes. Altogether, these results demonstrate that enhancing neurovascular signaling through pharmacological targeting of this pathway may be a viable approach for tissue-specific GMH intervention. They also demonstrate that timing and level are likely two major factors crucial for success. These findings thus provide critical new insights into both brain neurovascular biology and the intervention of GMH.

Effect of Vitamin E in Prevention of Intraventricular Hemorrhage in Preterm Neonates

Background

Germinal matrix-intraventricular hemorrhage (IVH) is the most common brain hemorrhage in preterm neonates. The importance of this hemorrhage lies in its severe complications. There is no definite treatment for IVH in neonates; therefore, the prevention of IVH should be considered. Some studies have shown that Vitamin E can probably decrease the risk of IVH and the other study has not shown its efficacy. The aim of this study is to evaluate the effects of Vitamin E on incidence and severity of IVH in preterm neonates.

Methods

This study is a randomized clinical trial conducted on 76 neonates with gestational age of ≤30 weeks in the Isfahan University of Medical Science. The neonates were divided into two groups. The group one was administered with 10 units of Vitamin E for 3 days and the second group with placebo. In the 4th and 7th days after birth, brain sonography was conducted to evaluate IVH. The presence of sepsis, incidence of necrotizing enterocolitis, and hypotension were examined.

Results

In this study, 76 neonates with the mean age of 28.49 ± 1.46 weeks participated. The incidence of hemorrhage in the 4th day was 26.3% in cases and 42.1% in controls with no significant difference (P = 0.3). The findings of the second sonography reported the incidence of IVH in 17.1% of cases and 36.8% of control group.

Conclusions

Based on findings of the current study, Vitamin E use did not significantly decrease IVH in neonates. Further studies with larger sample size are needed.

Biliverdin reductase-A attenuated GMH-induced inflammatory response in the spleen by inhibiting toll-like receptor-4 through eNOS/NO pathway

BACKGROUND

Germinal matrix hemorrhage (GMH) is a common neurologic event with high morbidity and mortality in preterm infants. Spleen has been reported to play a critical role in inflammatory responses by regulating peripheral immune cells which contributes to secondary brain injury.

METHODS

The current study investigated the mechanistic role of biliverdin reductase-A (BLVRA) in the splenic response and brain damage in neonates following a collagenase GMH model. Neurological outcomes and splenic weights were assessed. Neutrophil production and infiltration were quantitated in the spleen and brain, respectively. Western blot was performed in both splenic and brain tissues to measure protein levels of toll-like receptor 4 and proinflammatory cytokines.

RESULTS

BLVRA treatment alleviated GMH-induced developmental delay and attenuated splenic atrophy at 1 and 3 days after GMH. Quantification analysis showed that spleen-stored peripheral immune cells mobilized into circulation and infiltrated in the brain following GMH, which was abrogated by BLVRA administration, resulting in reduced splenic inflammatory response. Furthermore, we showed that regulation of eNOS/NO signaling by BLVRA stimulation blunted toll-like receptor-4 (TLR4) signal. The eNOS-generated NO, in part, translocated BLVRA into the nucleus, where BLVRA inhibited TLR4 expression.

CONCLUSION

We revealed a BLVRA-dependent signaling pathway in modulating the splenic inflammation in response to GMH via the eNOS/NO/TLR4 pathway.

Outcome of Ventriculosubgaleal Shunt in the Management of Infectious and Non-infectious Hydrocephalus in Pre-term Infants

Background:

Hydrocephalus in premature infants is an onerous disease. In such situations, choosing the best option for cerebrospinal fluid (CSF) diversion is difficult. Ventriculosubgaleal shunt is an effective method of temporary CSF diversion in such situations. In this retrospective study, we compare the outcome of ventriculosubgaleal shunt in premature infants with hydrocephalus of infectious and noninfectious etiology.

Materials and Methods:

All premature children with hydrocephalus secondary to various etiologies who underwent ventriculosubgaleal shunt were studied. The participants were grouped into two depending upon the etiology of hydrocephalus: Group 1 (infectious) and Group 2 (non-infectious). The primary outcome was a successful conversion to ventriculoperitoneal shunt (VPS) and the secondary outcome was mortality. Data were entered into statistical software SPSS version 16 and appropriate statistical analysis was performed to conclude any statistical significance between groups.

Results:

The study included 16 infants among whom 9 were in the infectious group and 7 in the non-infectious group. Primary end point of conversion to VPS was achieved in 55.5% of patients in group 1 and 85.7% in group 2. The secondary end point, i.e., mortality was observed in 44.4% of patients in group 1 and 14.2% in group 2. The average duration during which this was achieved was 40 days (range 20–60 days) in group 1 and 25 days (range 20–30 days) in group 2.

Conclusion:

Ventriculosubgaleal shunt is a safe and effective procedure in infants awaiting definitive VPS for hydrocephalus of infectious as well as noninfectious origin. There was no statistical difference in the rate of successful conversion to a permanent VPS from ventriculosubgaleal shunt in hydrocephalus of either etiologies. Complications and time for successful conversion were more in postmeningitic hydrocephalus.

Pushing the boundaries of ECLS: Outcomes in <34 week EGA neonates

PURPOSE

Extracorporeal life support (ECLS) is usually reserved for infants ≥34weeks estimated gestational age (EGA) owing to concerns about increased mortality and incidence of intracranial hemorrhage (ICH). We sought to characterize survival, rates of ICH, and complications in <34week EGA neonates placed on ECLS.

METHODS

752 neonates of EGA 29-34weeks were identified in the Extracorporeal Life Support Organization (ELSO) Registry (1976-2008). Data analyzed included birthweight, survival, pre-ECLS conditions, ventilatory parameters and complications (including ICH and other neurological outcomes). Data were compared using t-test, Chi-square and logistic regression analyses.

RESULTS

When compared to survival rates of 34week EGA neonates (58%), survival was statistically different for 29-33week EGA (48%, p=0.05). No significant difference in ICH incidence was seen between the 29-33week and 34week groups (21% vs. 17%, respectively), but a significant difference was seen in the incidence of cerebral infarct between groups (22% for 29-33weeks vs. 16% for 34weeks; p=0.03). ICH and survival did not correlate with EGA during logistic regression analysis.

CONCLUSIONS

Though rates of survival and cerebral infarction were worse at 29-33weeks EGA compared with 34weeks, these differences were modest and may be clinically acceptable. This suggests that EGA<34weeks may not be an absolute contraindication to use of ECLS.

LEVEL OF EVIDENCE

III.

Outcome of ventriculoperitoneal shunt and predictors of shunt revision in infants with posthemorrhagic hydrocephalus

OBJECT

Ventriculoperitoneal (VP) shunts in infants with posthemorrhagic hydrocephalus (PHH) are prone to failures, with some patients at risk for multiple revisions. The objective of our study is to observe long-term outcomes and identify factors leading to proximal and distal multiple failures.

METHODS

We performed a retrospective review of infants with PHH that required VP shunt placement between 1982 and 2014. These patients were monitored clinically and radiographically after VP shunt placement.

RESULTS

A total of 502 surgical procedures (initial shunt insertion and revisions) were performed, with 380 shunt revisions in 102 (84 %) patients. Median shunt survival time was 54 months (0.03-220 months). Shunt survival was significantly affected by the following factors: intraventricular hemorrhage (IVH, grade II-III, 95 months vs. grade IV, 28 months, p = 0.022), birth weight (<1.5 kg, 59 months vs. >1.5 kg, 22 months, p = 0.005), gestational age (>27 weeks, 90 months vs. <27 weeks, 20 months, p < 0.0001), distal vs. proximal revision (133 months vs. 48 months, p = 0.013), obstruction (yes, 78 months vs. no, 28 months, p = 0.007), and infection (no, 75 months vs. yes, 39 months, p = 0.045). Regression analysis revealed that multiple gestation, head circumference (>27 cm), congenital anomalies, infection, and obstruction increased the proximal and distal shunt malfunction.

CONCLUSION

Long-term outcome of VP shunt placement in infants revealed a relatively high rate of complications requiring shunt revision as late as 30 years after initial placement. Infants with VP shunts should be monitored lifelong of these patients by neurosurgeons.

Preterm cranial ultrasound scanning is both feasible and effective in a middle-income country

AIM

Cranial ultrasound is seldom used in middle-income countries, and the burden of preterm brain injury and its relationship to perinatal data is unknown. We assessed cranial ultrasound abnormalities in very low-birthweight (VLBW) infants and correlated the findings with perinatal data.

METHODS

VLBW Armenian infants receiving neonatal intensive care in 2012 were scanned from birth to term-equivalent age (TEA). Clinical data were collected prospectively.

RESULTS

We studied 100 VLBW infants with a median gestation of 30 weeks. Periventricular white matter echogenicity (PVE) lasting more than two weeks was seen in 34 infants, grade III intraventricular haemorrhage (IVH) in 10, haemorrhagic parenchymal infarction (HPI) in seven and cystic periventricular leukomalacia in two. Caudothalamic notch echogenicity appeared in 36 infants after two to three weeks, with cystic transformation in 22. At TEA, 17 infants had persisting PVEs and 55 had increased basal ganglia/thalamic (BGT) echogenicity. Lack of antenatal steroids was significantly associated with IVH and HPI and intubation at birth with IVH. Late BGT echogenicity was generally seen in infants without perinatal problems.

CONCLUSION

Our study demonstrated that cranial ultrasound can be used effectively in a middle-income country to identify high-risk infants and monitor quality of care.

Variables associated with the decreased risk of intraventricular haemorrhage in a large sample of neonates with respiratory distress syndrome

OBJECTIVE

Prematurity and other risk factors are associated with the development of intraventricular haemorrhage (IVH) in newborns with respiratory distress syndrome (RDS). Conversely, further analysis can determine what characteristics might be associated with a decreased risk of IVH.

STUDY DESIGN

By using International Classification of Diseases, Ninth Revision, Clinical Modification codes from data obtained from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project from 2000 to 2009, we identified a large number of cases of RDS. Multivariable logistic regression analysis identified potential variables associated with decreased risk of IVH.

RESULT

Our cohort included 194 621 neonates with RDS, of whom 20 386 (10.5%) developed IVH. Variables associated with decreased risk of both all grades of IVH and severe IVH only included infant of diabetic mother (IDM) status (OR 0.62 (0.54 to 0.70), p<0.001; OR 0.56 (0.42 to 0.74), p<0.001), Trisomy 21 (OR 0.45 (0.30 to 0.69), p<0.001; OR 0.38 (0.16 to 0.93), p=0.034), maternal hypertension (OR 0.62 (0.53 to 0.72), p<0.001; OR 0.28 (0.18 to 0.43), p<0.001), caesarean birth (OR 0.79 (0.74 to 0.84), p<0.001; OR 0.83 (0.73 to 0.94), p<0.001) and, consistent with prior studies, female gender (OR 0.85 (0.82 to 0.88), p<0.001; OR 0.76 (0.72 to 0.80), p<0.001). Polycythaemia (OR 0.67 (0.49 to 0.92), p=0.013; OR 0.79 (0.43 to 1.45), p=0.449) and hypothermia (OR 0.86 (0.75 to 0.99), p=0.039; OR 1.01 (0.81 to 1.28), p=0.903) were associated with lower risk of all IVH but not severe IVH only.

CONCLUSIONS

Previous associations with IVH such as lower birth weight were confirmed. However, infants in whom new variables such as IDM status were present were less likely to develop all IVH grades. Further analysis of these potential protective variables is necessary to better understand the pathophysiology of IVH.

A Century of Germinal Matrix Intraventricular Hemorrhage in Autopsied Premature Infants: A Historical Account

The care of premature infants in the 20th century is remarkable for technical advances that have dramatically improved survival, but little is known about temporal changes in the neuropathology of the premature infant over this time frame. We hypothesize that the autopsy rate of germinal matrix hemorrhage changed in the 20th century relative to combined influences of clinical interventions that were both harmful and helpful. We examined germinal matrix hemorrhage with intraventricular hemorrhage (GMH-IVH) in 345 premature infants (gestational age 25-36 weeks) autopsied at Boston Children's Hospital from 1914 to 2015. There was a median of 19 cases/decade (range 7-68). Over the course of the study median gestational age decreased from 33 to 27 gestational weeks (P<0.001), and median postnatal survival increased from 2 to 26 days (P=0.02). The incidence of GMH-IVH increased from 4.7% before 1960 to 50.0% from 1975 to 1980, and then decreased to 12.5% after 2005 (P<0.001). The incidence of GMH-IVH increased >3-fold around the time of the introduction of positive pressure ventilation into premature intensive care in the mid-1960s. The increased incidence of GMH-IVH in the 1970s-1980s likely reflects respiratory and hemodynamic imbalances complicating mechanical ventilation. We speculate that the subsequent decreased incidence of GMH-IVH likely reflects stabilization of respiratory function with improvements in ventilators and in ventilator management beginning in the 1970s and the use of surfactant and antenatal steroids in the 1980s.

PPARγ-induced upregulation of CD36 enhances hematoma resolution and attenuates long-term neurological deficits after germinal matrix hemorrhage in neonatal rats

Germinal matrix hemorrhage remains the leading cause of morbidity and mortality in preterm infants in the United States with little progress made in its clinical management. Survivors are often afflicted with long-term neurological sequelae, including cerebral palsy, mental retardation, hydrocephalus, and psychiatric disorders. Blood clots disrupting normal cerebrospinal fluid circulation and absorption after germinal matrix hemorrhage are thought to be important contributors towards post-hemorrhagic hydrocephalus development. We evaluated if upregulating CD36 scavenger receptor expression in microglia and macrophages through PPARγ stimulation, which was effective in experimental adult cerebral hemorrhage models and is being evaluated clinically, will enhance hematoma resolution and ameliorate long-term brain sequelae using a neonatal rat germinal matrix hemorrhage model. PPARγ stimulation (15d-PGJ2) increased short-term PPARγ and CD36 expression levels as well as enhanced hematoma resolution, which was reversed by a PPARγ antagonist (GW9662) and CD36 siRNA. PPARγ stimulation (15d-PGJ2) also reduced long-term white matter loss and post-hemorrhagic ventricular dilation as well as improved neurofunctional outcomes, which were reversed by a PPARγ antagonist (GW9662). PPARγ-induced upregulation of CD36 in macrophages and microglia is, therefore, critical for enhancing hematoma resolution and ameliorating long-term brain sequelae.

Risk Factors for Intraventricular Hemorrhage in Preterm Infants Born at 34 Weeks of Gestation or Less Following Preterm Premature Rupture of Membranes

OBJECTIVE

The objective of this study is to identify possible perinatal risk factors related to intraventricular hemorrhage (IVH) in preterm infants born at 34 weeks of gestation or less following preterm premature rupture of membranes (pPROM).

METHODS

A total of 292 preterm infants born at 34 weeks of gestation or less following pPROM were enrolled in the study, while 155 newborns with incomplete data, especially those that lack histological examination of the placenta, maternal details, and neonatal characteristics, have been further excluded. Finally, data of 137 preterm infants were included in the analysis. All infants underwent ultrasonographic screening for IVH. Thirty-three infants with IVH were considered as cases and 104 infants without IVH were considered as controls. The association between risk factors and IVH was evaluated by univariate and multivariate logistic regression analyses.

RESULTS

The incidence of IVH in preterm infants born at 34 weeks of gestation or less following pPROM was 24.1%, while the incidence of maternal chorioamnionitis was 43.8%. By univariate analysis, gestational age, birth weight, asphyxia resuscitation, maternal chorioamnionitis, fetal distress, amniotic fluid index, and latency of the rupture of membranes to birth were found to be significantly different between the 2 groups. By logistic regression analysis, lower gestational age, low birth weight, asphyxia resuscitation, and maternal chorioamnionitis were found to be independent risk factors for IVH.

CONCLUSION

Lower gestational age, low birth weight, asphyxia resuscitation, and maternal chorioamnionitis are independent risk factors for IVH in preterm infants born at 34 weeks of gestation or less following pPROM.

Osteopontin-Rac1 on Blood-Brain Barrier Stability Following Rodent Neonatal Hypoxia-Ischemia

Osteopontin (OPN) is a neuroprotective molecule that is upregulated following rodent neonatal hypoxic-ischemic (nHI) brain injury. Because Rac1 is a regulator of blood-brain barrier (BBB) stability, we hypothesized a role for this in OPN signaling. nHI was induced by unilateral ligation of the right carotid artery followed by hypoxia (8 % oxygen for 2 h) in P10 Sprague-Dawley rat pups. Intranasal (iN) OPN was administered at 1 h post-nHI. Groups consisted of: (1) Sham, (2) Vehicle, (3) OPN, and (4) OPN + Rac1 inhibitor (NSC23766). Evans blue dye extravasation (BBB permeability) was quantified 24 h post-nHI, and brain edema at 48 h. Increased BBB permeability and brain edema following nHI was ameliorated in the OPN treatment group. However, those rat pups receiving OPN co-treatment with the Rac1 inhibitor experienced no improvement compared with vehicle. OPN protects the BBB following nHI, and this was reversed by Rac1 inhibitor (NSC23766).

Comparison of the use of ventricular access devices and ventriculosubgaleal shunts in posthaemorrhagic hydrocephalus: systematic review and meta-analysis

INTRODUCTION

Ventricular access devices (VAD) and ventriculosubgaleal shunts (VSGS) are currently both used as temporising devices to affect CSF drainage in neonatal posthaemorrhagic hydrocephalus (PHH), without clear evidence of superiority of either procedure. In this systematic review and meta-analysis, we compared the VSGS and VAD regarding complication rates, ventriculoperitoneal shunt conversion and infection rates, and mortality and long-term disability.

METHODS

The review was registered with the PROSPERO international prospective register of systematic reviews (registration number CRD42015019750) and was conducted in accordance with PRISMA guidelines.

RESULTS AND CONCLUSIONS

The literature search of five databases identified 338 publications, of which 5 met the inclusion criteria. All were retrospective cohort studies (evidence class 3b and 4). A significantly lower proportion of patients with a VSGS required CSF tapping compared to patients with a VAD (log OR -4.43, 95% CI -6.14 to -2.72). No other significant differences between the VAD and VSGS were identified in their rates of infection (log OR 0.03, 95% CI -0.77 to 0.84), obstruction (log OR 1.25, 95% CI -0.21 to 2.71), ventriculoperitoneal shunt dependence (log OR -0.06, 95% CI -0.93 to 0.82), subsequent shunt infection (log OR 0.23, 95% CI -0.61 to 1.06), mortality (log OR 0.37, 95% CI -0.95 to 1.70) or long-term disability (p = 0.9). In all studies, there was a lack of standardised criteria, variations between surgeons in heterogeneous cohorts of limited sample size and a lack of neurodevelopmental follow-up. This affirms the importance of an ongoing multicentre, prospective pilot study comparing these two temporising procedures to enable a more robust comparison.

Head Position Change Is Not Associated with Acute Changes in Bilateral Cerebral Oxygenation in Stable Preterm Infants during the First 3 Days of Life

OBJECTIVE

Several recent intraventricular hemorrhage prevention bundles include midline head positioning to prevent potential disturbances in cerebral hemodynamics. We aimed to study the impact of head position change on regional cerebral saturations (SctO2) in preterm infants (< 30 weeks gestational age) during the first 3 days of life.

STUDY DESIGN

Bilateral SctO2 was measured by near-infrared spectroscopy. The infant's head was turned sequentially to each side from midline (baseline) in 30-minute intervals while keeping the body supine. Bilateral SctO2 before and after each position change were compared using paired t-test.

RESULTS

In relatively stable preterm infants (gestational age 26.5 ± 1.7 weeks, birth weight 930 ± 220 g; n = 20), bilateral SctO2 remained within normal range (71.1-75.3%) when the head was turned from midline position to either side.

CONCLUSION

Stable preterm infants tolerated brief changes in head position from midline without significant alternation in bilateral SctO2; the impact on critically ill infants needs further evaluation.

Interpretation of clotting tests in the neonate

There are significant differences between the coagulation system in neonates compared with children and adults. Abnormalities of standard coagulation tests are common within the neonatal population. The laboratory tests of activated partial thromboplastin time (aPTT) and prothrombin time (PT) were developed to investigate coagulation factor deficiencies in patients with a known bleeding history, and their significance and applied clinical value in predicting bleeding (or thrombotic) risk in critically ill patients is weak. Routine screening of coagulation on admission to the neonatal intensive care unit leads to increased use of plasma for transfusion. Fresh frozen plasma (FFP) is a human donor plasma frozen within a short specified time period after collection (often 8 h) and then stored at -30°C. FFP has little effect on correcting abnormal coagulation tests when mild and moderate abnormalities of PT are documented in neonates. There is little evidence of effectiveness of FFP in neonates. A large trial by the Northern Neonatal Nursing Initiative assessed the use of prophylactic FFP in preterm infants and reported no improvement in clinical outcomes in terms of mortality or severe disability. An appropriate FFP transfusion strategy in neonates should be one that emphasises the therapeutic use in the face of bleeding rather than prophylactic use in association with abnormalities of standard coagulation tests that have very limited predictive value for bleeding.

An extracorporeal artificial placenta supports extremely premature lambs for 1 week

PURPOSE

The treatment of extreme prematurity remains an unsolved problem. We developed an artificial placenta (AP) based on extracorporeal life support (ECLS) that simulates the intrauterine environment and provides gas exchange without mechanical ventilation (MV) and compared it to the current standard of neonatal care.

METHODS

Extremely premature lambs (110-120 days; term=145d) were used. AP lambs (n=9) were cannulated (jugular drainage, umbilical vein reinfusion) for ECLS. Control lambs (n=7) were intubated, ventilated, given surfactant, and transitioned to high-frequency oscillatory ventilation. All lambs received parenteral nutrition, antibiotics, and steroids. Hemodynamics, blood gases, hemoglobin, and circuit flows were measured.

RESULTS

Four premature lambs survived for 1 week on the AP, with one surviving 6 days. Adequate oxygenation and ventilation were provided by the AP. The MV lambs survived 2-8 hours. Each of these lambs experienced a transient improvement with surfactant, but developed progressive hypercapnea and hypoxia despite high airway pressures and HFOV.

CONCLUSIONS

Extremely premature lambs were supported for 1 week with the AP with hemodynamic stability and adequate gas exchange. Mechanically ventilated lambs succumbed within 8 hours. Further studies will assess control of fetal circulation and organ maturation on the AP.

Minocycline-induced attenuation of iron overload and brain injury after experimental germinal matrix hemorrhage

Germinal matrix hemorrhage (GMH) is the most important adverse neurologic event during the newborn period. Evidence has shown that neonates with GMH and hydrocephalus have more severe damage compared to those with GMH alone. Our preliminary study demonstrated the role of iron in hydrocephalus and brain damage in adult rats following intraventricular hemorrhage. Therefore, the aim of the current study was to investigate iron accumulation and iron-handling proteins in a rat model of GMH and whether minocycline reduces iron overload after GMH and iron-induced brain injury in vivo. This study was divided into two parts. In the first part, rats received either a needle insertion or an intracerebral injection of 0.3 U of clostridial collagenase VII-S. Brain iron and brain iron handling proteins (heme oxygenase-1 and ferritin) were measured. In the second part, rats with a GMH were treated with minocycline or vehicle. Brain edema, brain cell death, hydrocephalus, iron-handling proteins and long-term motor function were examined. The result showed iron accumulation and upregulation of iron-handling proteins after GMH. Minocycline treatment significantly reduced GMH-induced brain edema, hydrocephalus and brain damage. Minocycline also suppressed upregulation of ferritin after GMH. In conclusion, the current study found that iron plays a role in brain injury following GMH and that minocycline reduces iron overload after GMH and iron-induced brain injury.

Patent ductus arteriosus ligation and adverse outcomes: causality or bias?

Observational studies have associated patent ductus arteriosus (PDA) ligation in preterm infants with increased chronic lung disease (CLD), retinopathy of prematurity, and neurodevelopmental impairment at long-term follow-up. Although the biological rationale for this association is incompletely understood, there is an emerging secular trend toward a permissive approach to the PDA. However, insufficient adjustment for postnatal, pre-ligation confounders, such as intraventricular hemorrhage and the duration and intensity of mechanical ventilation, suggests the presence of residual bias due to confounding by indication, and obliges caution in interpreting the ligation-morbidity relationship. A period of conservative management after failure of medical PDA closure may be considered to reduce the number of infants treated with surgery. Increased mortality and CLD in infants with persistent symptomatic PDA suggests that surgical ligation remains an important treatment modality for preterm infants.

A Systematic Review and Meta-analysis of the Timing of Early Intraventricular Hemorrhage in Preterm Neonates: Clinical and Research Implications

A considerable number of intraventricular hemorrhages (IVH) occur within the first hours of life (HOL). Temporality between IVH and its antecedents as well as a consistent definition of "early IVH" is lacking in a large and growing body of literature. We performed a systematic review of prospective studies that reported onset of IVH in preterm neonates within the first HOL and afterwards. The English literature was searched using three databases up to March 2013. Four timing periods of IVH can be compared in 16 identified studies: 0-6; 7-12; 13-24; after 24 HOL. The 0-6 and after 24 HOL were the major modes of IVH timing. Pooled IVH proportions were estimated through a meta-analysis of studies that were conducted after antenatal steroid and surfactant era. In neonates weighing ≤1500 g at birth: 48% of IVH (95% CI: 42-58%, 5 studies, 279 IVH cases) occurred during 0-6 HOL and 38% (95% CI: 19-57%, 4 studies, 241 IVH cases) after 24 HOL. The 0-6 HOL is the shortest, most vulnerable period for IVH, thus, an early IVH is an IVH occurs in it. Such early IVH had prognostic, etiological/preventive and medicolegal implications. Accordingly, preterm neonates at risk of IVH should have their first routine screening head ultrasound at about 6 HOL. Future research exploring the antecedents of IVH should guaranty the temporality between these antecedents and IVH. Additional research will be required to determine whether the long term neurological outcomes of early and late IVH are the same.

The protective effect of glibenclamide in a model of hemorrhagic encephalopathy of prematurity

We studied a model of hemorrhagic encephalopathy of prematurity (EP) that closely recapitulates findings in humans with hemorrhagic EP. This model involves tandem insults of 20 min intrauterine ischemia (IUI) plus an episode of elevated venous pressure induced by intraperitoneal glycerol on post-natal day (P) 0. We examined Sur1 expression, which is upregulated after focal ischemia but has not been studied after brief global ischemia including IUI. We found that 20 min IUI resulted in robust upregulation of Sur1 in periventricular microvessels and tissues. We studied tandem insult pups from untreated or vehicle-treated dams (TI-CTR), and tandem insult pups from dams administered a low-dose, non-hypoglycemogenic infusion of the Sur1 blocker, glibenclamide, for 1 week after IUI (TI-GLIB). Compared to pups from the TI-CTR group, pups from the TI-GLIB group had significantly fewer and less severe hemorrhages on P1, performed significantly better on the beam walk and accelerating Rotarod on P35 and in tests of thigmotaxis and rapid learning on P35–49, and had significantly greater body and brain weights at P52. We conclude that low-dose glibenclamide administered to the mother at the end of pregnancy protects pups subjected to IUI from post-natal events of elevated venous pressure and its consequences.

PDA ligation and health outcomes: a meta-analysis

BACKGROUND AND OBJECTIVE

Patent ductus arteriosus (PDA) ligation has been variably associated with neonatal morbidities and neurodevelopmental impairment (NDI). The objective was to systematically review and meta-analyze the impact of PDA ligation in preterm infants at <32 weeks' gestation on the risk of mortality, severe neonatal morbidities, and NDI in early childhood.

METHODS

Medline, Embase, Cochrane Central Register of Controlled Trials, Education Resources Information Centre (ERIC), Cumulative Index to Nursing and Allied Health (CINAHL), PsycINFO, and the Dissertation database were searched (1947 through August 2013). Risk of bias was assessed by using the Newcastle-Ottawa Scale and the Cochrane Risk of Bias tool. Meta-analyses were performed by using a random-effects model. Unadjusted and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were pooled when appropriate.

RESULTS

Thirty-nine cohort studies and 1 randomized controlled trial were included. Nearly all cohort studies had at least moderate risk of bias mainly due to failure to adjust for survival bias and important postnatal preligation confounders such as ventilator dependence, intraventricular hemorrhage, and sepsis. Compared with medical treatment, surgical ligation was associated with increases in NDI (aOR: 1.54; 95% CI: 1.01-2.33), chronic lung disease (aOR: 2.51; 95% CI: 1.98-3.18), and severe retinopathy of prematurity (aOR: 2.23; 95% CI: 1.62-3.08) but with a reduction in mortality (aOR: 0.54; 95% CI: 0.38-0.77). There was no difference in the composite outcome of death or NDI in early childhood (aOR: 0.95; 95% CI: 0.58-1.57).

CONCLUSIONS

Surgical ligation of PDA is associated with reduced mortality, but surviving infants are at increased risk of NDI. However, there is a lack of studies addressing survival bias and confounding by indication.

Indomethacin prophylaxis to prevent intraventricular hemorrhage: association between incidence and timing of drug administration

OBJECTIVE

To test the hypothesis that administration of indomethacin prophylaxis before 6 hours of life results in a lower incidence of intraventricular hemorrhage (IVH) compared with administration after 6 hours of life, and that the effects of early prophylaxis depend on gestational age (GA) and sex in very low birth weight infants (birth weight <1250 g).

STUDY DESIGN

Very low birth weight infants admitted to our neonatal intensive care unit between 2003 and 2010 who received indomethacin prophylaxis were analyzed retrospectively. Exclusion criteria included unknown time of indomethacin prophylaxis, death at <12 hours of life, congenital anomalies, and unavailable head ultrasound report. Infants were dichotomized based on the timing of indomethacin prophylaxis (<6 hours or >6 hours of life) to compare incidence of IVH all grades and severe (grade 3-4) IVH. Secondary analyses examined the effects of the time of indomethacin prophylaxis initiation by GA and sex on the incidence of IVH.

RESULTS

A total of 868 infants (431 males and 437 females) met the criteria for analysis. Indomethacin prophylaxis was given at <6 hours of life in 730 infants and at >6 hours of life to 168 infants. The 2 groups differed with respect to antenatal steroid exposure, GA, outborn prevalence, and pneumothoraces. After multivariate analysis, there were no between-group differences in all-grade or severe IVH. However, females, but not males, treated at <6 hours of life had a lower incidence of severe IVH (P < .05), particularly at lower GAs.

CONCLUSION

Prophylactic indomethacin administered before 6 hours of life is not associated with lower incidence of IVH.

Delayed germinal matrix hemorrhage induced by ventriculoperitoneal shunt insertion for congenital hydrocephalus

Germinal matrix hemorrhages (GMHs) are typically seen in preterm neonates during the first 4 days of life. The authors encountered 2 children with late-onset GMH subsequent to ventriculoperitoneal (VP) shunt insertion for congenital hydrocephalus. Both children were delivered at full term with normal body weight, although they were compromised with the preceding hypoxic events prior to shunt insertion. The first case involved a female infant with severe craniofacial deformities. Because of aspiration pneumonia related to the comorbid upper airway stenosis, endotracheal intubation with intermittent mechanical ventilation was necessary. The associated congenital hydrocephalus was treated with VP shunt insertion when she was 35 days of age, and GMH was confirmed 1 week after shunt placement. During a period of conservative observation, the hemorrhage resolved without any neurological deterioration. The second case involved a male infant with a large intraparenchymal cyst on the left parietal portion. He was intubated for pneumonia at 1 month of age. He had associated congenital hydrocephalus that was progressive, and he was treated with VP shunting at 69 days of age, after his pneumonia had resolved. Postoperative GMH was confirmed, although hydrocephalus was well controlled by VP shunt insertion. Observed conservatively, he fared well and the GMH resolved. These 2 cases had unique features in common; both had congenital anomalies in the CNS and respiratory problems before shunting. The hypoxic insults on the residual germinal matrix layer and sudden decrease in CSF pressure may relate to the occurrence of these late-onset GMHs.

Analysis of factors affecting ventriculoperitoneal shunt survival in pediatric patients

PURPOSE

Management of hydrocephalus with insertion of ventriculoperitoneal (VP) shunt is associated with significant complications in both adult and pediatric patients. These may be more common in developing countries due to poor economic conditions and a dearth of available resources. We report a 6 years' experience with VP shunt insertion in pediatric patients from a developing country, focusing particularly on factors affecting shunt failure.

METHODS

Patients aged below 15 years, who had undergone insertion of VP shunts for hydrocephalus during the years 2006 to 2011, were included. A retrospective analysis of shunt survival was performed using Kaplan-Meier curves and Logrank (Cox-Mantel) test.

RESULTS

Among the total 113 patients, the most common etiologies of hydrocephalus were congenital hydrocephalus (19.5 %), brain tumors (14.2 %), and postcranial surgery (13.3 %). Overall shunt failure at a mean follow-up of 11 months was 23 % with the median time to first shunt failure being 68 days. Shunt survival was worse in patients with meningitis (p = 0.024), aqueductal stenosis (p = 0.008), postcranial surgery hydrocephalus (p = 0.006), Caesarean mode of delivery (p = 0.036), congenital abnormalities (p = 0.031), and a past history of surgical excision of mass lesion (p = 0.044).Frequency of shunt failure was also significantly affected by the location of brain tumor (p = 0.015) and prematurity (p = 0.015).

CONCLUSION

Premature infants still have a higher rate of shunt failure. Patients with meningitis, aqueductal stenosis, postcranial surgery hydrocephalus, congenital abnormalities, and a past history of surgical excision of mass lesion may have early shunt failure. However, the frequency of shunt failure that we observed (23 %) was much lower than that quoted earlier in the literature and this may be a consequence of rigorous periodic evaluation of patients with VP shunt in situ.

Incidence of brain injuries in premature infants with gestational age ≤ 34 weeks in ten urban hospitals in China

BACKGROUND

There is a large number (1.5 million per year) of premature births in China. It is necessary to obtain the authentic incidences of intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL), the common brain injuries, in Chinese premature infants. The present multicenter study aimed to investigate the incidence of brain injuries in premature infants in ten urban hospitals in China.

METHODS

The research proposal was designed by the Subspecialty Group of Neonatology of Pediatric Society of the Chinese Medical Association. Ten large-scale urban hospitals voluntarily joined the multicenter investigation. All premature infants with a gestational age ≤ 34 weeks in the ten hospitals were subjected to routine cranial ultrasound within three days after birth, and then to repeated ultrasound every 3-7 days till their discharge from the hospital from January 2005 to August 2006. A uniform data collection sheet was designed to record cases of brain injuries.

RESULTS

The incidences of overall IVH and severe IVH were 19.7% (305/1551) and 4.6% (72/1551), respectively with 18.4% (56/305) for grade 1, 58.0% (177/305) for grade 2, 17.7% (54/305) for grade 3 and 5.9% (18/305) for grade 4 in nine hospitals. The incidences of overall PVL and cystic PVL were 5.0% (89/1792) and 0.8% (14/1792) respectively, with 84.3% (75/89) for grade 1, 13.5% (12/89) for grade 2, and 2.2% (2/89) for grade 3 in the ten hospitals. The statistically significant risk factors that might aggravate the severity of IVH were vaginal delivery (OR=1.883, 95% CI: 1.099-3.228, P=0.020) and mechanical ventilation (OR=4.150, 95% CI: 2.384-7.223, P=0.000). The risk factors that might result in the development of cystic PVL was vaginal delivery (OR=21.094, 95% CI: 2.650-167.895, P=0.000).

CONCLUSIONS

The investigative report can basically reflect the incidence of brain injuries in premature infants in major big cities of China. Since more than 60% of the Chinese population live in the rural areas of China, it is expected to undertake a further multicenter investigation covering the rural areas in the future.

Morphological evaluation of the cerebral blood vessels in the late gestation fetal sheep following hypoxia in utero

Hypoxia can significantly contribute to the development of permanent brain injury in the term neonate; however the response of cerebral blood vessels is not well understood. This study aimed to quantitatively measure vascular density and morphology using laminin immunohistochemistry as a marker of blood vessels, and determine the effects of a single, severe bout of hypoxia (umbilical cord occlusion, UCO) late in gestation on the developing cerebrovasculature in fetal sheep. At 124-126 days gestation singleton fetal sheep underwent surgery for implantation of catheters and placement of an inflatable cuff around the umbilical cord. A 10 min UCO or sham UCO (n=5) occurred at 132 days gestation. Fetal brains were collected at 24 h (n=5) or 48 h (n=4) after UCO for vascular density and morphology analysis of laminin immunohistochemistry. 48 h following a single, brief bout of severe hypoxia late in gestation decreased vascular density was seen in the caudate nucleus and no changes in vascular morphology occurred. However closer analysis revealed a significant shift in the frequency of smaller (≤10 μm) to larger (≤100 μm) perimeter blood vessels in periventricular and subcortical white matter. Close examination of the frequency distribution of vascular perimeter highlights that alterations in vascular morphology persist in the near term fetal brain for up to 48 h following a brief (10 min) hypoxia in white but not gray matter. These findings suggest that the near term brain may still be vulnerable to white matter injury following in utero hypoxia.

Tandem insults of prenatal ischemia plus postnatal raised intrathoracic pressure in a novel rat model of encephalopathy of prematurity

OBJECT

Encephalopathy of prematurity (EP) is common in preterm, low birth weight infants who require postnatal mechanical ventilation. The worst types of EP are the hemorrhagic forms, including choroid plexus, germinal matrix, periventricular, and intraventricular hemorrhages. Survivors exhibit life-long cognitive, behavioral, and motor abnormalities. Available preclinical models do not fully recapitulate the salient features of hemorrhagic EP encountered in humans. In this study, the authors evaluated a novel model using rats that featured tandem insults of transient prenatal intrauterine ischemia (IUI) plus transient postnatal raised intrathoracic pressure (RIP).

METHODS

Timed-pregnant Wistar rats were anesthetized and underwent laparotomy on embryonic Day 19. Intrauterine ischemia was induced by clamping the uterine and ovarian vasculature for 20 minutes. Natural birth occurred on embryonic Day 22. Six hours after birth, the pups were subjected to an episode of RIP, induced by injecting glycerol (50%, 13 μl/g intraperitoneally). Control groups included naive, sham surgery, and IUI alone. Pathological, histological, and behavioral analyses were performed on pups up to postnatal Day 52.

RESULTS

Compared with controls, pups subjected to IUI+RIP exhibited significant increases in postnatal mortality and hemorrhages in the choroid plexus, germinal matrix, and periventricular tissues as well as intraventricularly. On postnatal Days 35-52, they exhibited significant abnormalities involving complex vestibulomotor function and rapid spatial learning. On postnatal Day 52, the brain and body mass were significantly reduced.

CONCLUSIONS

Tandem insults of IUI plus postnatal RIP recapitulate many features of the hemorrhagic forms of EP found in humans, suggesting that these insults in combination may play important roles in pathogenesis.

Severe intra- and periventricular hemorrhage: role of arteriolosclerosis related to maternal smoke

OBJECTIVE

The authors aimed to describe the atherosclerotic lesions of the cerebral arterioles as a substrate of their rupture and bleeding.

METHODS

The study was performed on the brain of nine Caucasian fetal victims of intra- and periventricular hemorrhage, all grade IV, and nine control cases.

RESULTS

In the nine victims of hemorrhage, the arteriolar wall structure was altered, focally transformed into a deposit of amorphous eosinophilic material. Such changes often affected the full thickness of the wall causing rupture and hemorrhage. In eight of these cases and in two victims of the control group, the mothers were heavy cigarette smokers (15-20 cigarettes/day) before and during pregnancy.

CONCLUSION

The authors conclude that intra- and periventricular hemorrhage can be ascribed to the toxic effects of prenatal absorption of nicotine.

Infantile posthemorrhagic hydrocephalus

INTRODUCTION

Intraventricular/germinal matrix hemorrhage affects 7-30% of premature neonates, 25-80% of whom (depending on the grade of the hemorrhage) will develop hydrocephalus requiring shunting. Predisposing factors are low birth weight and gestational age.

MATERIAL

There is increasing evidence for the role of TGF-β1 in the pathogenesis of hydrocephalus, but attempts to develop treatment modalities to clear the cerebrospinal fluid (CSF) from blood degradation products have not succeeded so far. Ultrasound is a valuable screening tool for high-risk infants and magnetic resonance imaging is increasingly utilized to differentiate progressive hydrocephalus from ex vacuo ventriculomegaly, evaluate periventricular parenchymal damage, decide on the surgical treatment of hydrocephalus, and follow up these patients in the long term. Treatment of increasing ventriculomegaly and intracranial hypertension in the presence of hemorrhagic CSF can involve a variety of strategies, all with relative drawbacks, aiming to drain the CSF while gaining time for it to clear and the neonate to reach term and become a suitable candidate for shunting. Eventually, patients with progressive ventriculomegaly causing intracranial hypertension, who have reached term and their CSF has cleared from blood products, will need shunting.

CONCLUSION

Cognitive long-term outcome is influenced more by the effect of the initial hemorrhage and other perinatal events and less by hydrocephalus, provided that this has been addressed timely in the early postnatal period. Shunting can have many long-term side effects due to mechanical complications and overdrainage. In particular, patients with posthemorrhagic hydrocephalus are more susceptible to multiloculated hydrocephalus and encysted fourth ventricle, both of which are challenging to treat.

Incidence of hydrocephalus and the need to ventriculoperitoneal shunting in premature infants with intraventricular hemorrhage: risk factors and outcome

OBJECTIVE

To investigate the associated risk factors for ventriculoperitoneal (VP) shunting in infantile hydrocephalus following intraventricular hemorrhage (IVH) in premature infants.

METHODS

A historical cohort study was conducted, consisting of 97 premature infants in whom the diagnosis of IVH was previously made by cranial ultrasound and were referred to pediatric neurosurgery clinic and/or neonatal intensive care unit of Children's Hospital Medical Center in Tehran, Iran, from April 2004 to March 2009. Among the patients, those who were followed up for at least 6 months after the diagnosis of IVH were included in the study, and data regarding signs and symptoms of increased intracranial pressure, cranial ultrasound, non-surgical treatment (CSF drainage and/or acetazolamide), and shunt requirement were extracted. Patients who required VP shunting were followed up for at least 6 months thereafter considering shunt infection.

RESULTS

All the patients were followed up for at least 1 year, except for three who died at the ages of 6 (two of them) and 7 months. Thirty five percent (35%) of patients required VP shunting, in all of whom IVH was of grade 3 or 4. The need for VP shunting in these patients was predicted only by the severity of IVH. Non-surgical treatments for IVH had no statistically significant effect on shunt requirement. Moreover, 11 of 31 patients with shunt developed shunt infection, which was significantly associated with repeated cerebrospinal fluid (CSF) drainage.

CONCLUSION

It is suggested that children with IVH, especially of higher grades, should be followed up meticulously (by signs, symptoms, and periodic cranial ultrasounds). Non-surgical treatments are considered for patients requiring VP shunting who are not good candidates for immediate surgical intervention. The only predictor for surgical intervention was the grade of IVH.