Brain structure and function in the fourth decade of life after extremely low birth weight: An MRI and EEG study

OBJECTIVE

To examine potential long-term effects of extremely low birth weight (ELBW; ≤ 1000 g) on adult brain structure, brain function, and cognitive-behavioral performance.

METHODS

A subset of survivors from the prospectively-followed McMaster ELBW Cohort (n = 23, MBW = 816 g) and their peers born at normal birth weight (NBW; ≥ 2500 g; n = 14, MBW = 3361 g) provided T1-weighted magnetic resonance imaging (MRI) brain scans, resting electroencephalographic (EEG) recordings, and behavioral responses to a face-processing task in their early thirties.

RESULTS

Visual discrimination accuracy for human faces, resting EEG alpha power, and long-distance alpha coherence were lower in ELBW survivors than NBW adults, and volumes of white matter hypointensities (WMH) were higher. Across groups, face-processing performance was correlated positively with posterior EEG spectral power and long-distance alpha and theta coherence, and negatively with WMH. The associations between face-processing scores and parietal alpha power and theta coherence were reduced after adjustment for WMH.

CONCLUSIONS

Electrocortical activity, brain functional connectivity, and higher-order processing ability may be negatively affected by WMH burden, which is greater in adults born extremely preterm.

SIGNIFICANCE

Decrements in electrocortical activity and behavioral performance in adult ELBW survivors may be partly explained by increased WMH volumes in this vulnerable population.

Statistical Modeling of Heart Rate Variability to Unravel the Factors Affecting Autonomic Regulation in Preterm Infants

Analyzing heart rate variability (HRV) in preterm infants can help track maturational changes and subclinical signatures of disease. We conducted an observational study to characterize the effect of demographic and cardiorespiratory factors on three features of HRV using a linear mixed-effects model. HRV-features were tailored to capture the unique physiology of preterm infants, including the contribution of transient pathophysiological heart rate (HR) decelerations. Infants were analyzed during stable periods in the incubator and subsequent sessions of Kangaroo care (KC) - an intervention that increases comfort. In total, 957 periods in the incubator and during KC were analyzed from 66 preterm infants. Our primary finding was that gestational age (GA) and postmenstrual age (PMA) have the largest influence on HRV while the HR and breathing rate have a considerably smaller effect. Birth weight and gender do not affect HRV. We identified that with increasing GA and PMA, overall HRV decreased and increased respectively. Potentially these differences can be attributed to distinct trajectories of intra- and extrauterine development. With increasing GA, the propensity towards severe HR decelerations decreases, thereby reducing overall variability, while with increasing PMA, the ratio of decelerations and accelerations approaches unity, increasing overall HRV.

Efficacy of macrolides on gastric motility in extremely low birth weight infants

BACKGROUND

The efficacy of macrolide treatment on gastrointestinal motility and acquirement of feeding tolerance in extremely low birth weight (ELBW) infants are controversial. This study aimed to evaluate clinical effects of parenterally administered erythromycin (EM) and clarithromycin (CAM) on gastrointestinal motility in ELBW infants.

METHODS

ELBW infants treated in Tokyo Medical University Hospital were retrospectively studied. Several outcomes of ELBW infants treated with EM or CAM were compared with those recognized before initiation of the medication, as well as with those of patients with no macrolide treatment. The primary outcomes included average gastric residual volume that was evaluated 3 hours after enteral feeding. Secondary outcomes were the number of patients who developed feeding intolerance, stool frequency, and other adverse events, such as respiratory comorbidities and pyloric stenosis.

RESULTS

Among a total of 53 infants, 20 and 13 were treated with EM and CAM, respectively, whereas 20 infants were not administered macrolides. The gastric residual volume was significantly decreased after initiation of medication compared with before medication in the EM group, whereas that of the untreated group showed no change. When the EM and CAM groups were combined, the gastric residual volume was also significantly decreased after treatment compared with before treatment. An increase in stool frequency and pyloric stenosis were not observed in the groups.

CONCLUSION

EM might be effective for acquiring feeding tolerance in ELBW infants. A future prospective study with a larger population is required to determine the efficacy of CAM.

Feeding-Induced Cortisol Response in Newborn Infants

CONTEXT

Understanding the biological rhythms and stress response in sick newborns is important to minimize the negative effects of intensive care. Salivary cortisol has been used as a noninvasive surrogate marker of adrenal function; however, understanding of its control variables is insufficient.

OBJECTIVE

To investigate the presence of feeding-induced cortisol response and its control variables in newborns.

DESIGN, SETTING, AND PATIENTS

Fifty-three newborn infants, who were between 30 and 40 weeks' corrected age and were on 3-hourly regular oral/enteral feeding, were recruited between January 2013 and June 2014.

MAIN OUTCOME MEASURE

Saliva samples were collected before and 1 hour after regular feeding. Dependence of cortisol levels (adjusted for postnatal age) and their feeding-related elevation on clinical variables was assessed by using generalized estimating equations.

RESULTS

Higher cortisol levels were associated with corrected age ≥37 weeks and saliva samples collected after feeding (both P < 0.001). Oral feeding was associated with a greater feeding-induced cortisol response compared with exclusive enteral feeding (P = 0.034), whereas a prolonged feeding duration (≥30 minutes) was associated with a reduced cortisol response compared with brief feeding (<30 minutes) (P < 0.001). Gestational age, corrected age, antenatal/postnatal glucocorticoids, type of milk, and daily feeding volume had no effect on cortisol response.

CONCLUSIONS

Feeding-induced cortisol response was observed in newborns. The cortisol response was more prominent following oral feeding and was reduced with prolonged feeding. Future studies may investigate whether feeding-induced cortisol response plays a role in the acquisition of adrenal ultradian and diurnal rhythms.

The Other Side of the Incubator: A Preemie Turns 40 Years Old

Deb Discenza interviews Geoff, a preemie born almost 40 years ago, and gets unique insight into his birth, his NICU stay, and life afterward.

Protective Effect of Dual-Strain Probiotics in Preterm Infants: A Multi-Center Time Series Analysis

Objective

To determine the effect of dual-strain probiotics on the development of necrotizing enterocolitis (NEC), mortality and nosocomial bloodstream infections (BSI) in preterm infants in German neonatal intensive care units (NICUs).

Design

A multi-center interrupted time series analysis.

Setting

44 German NICUs with routine use of dual-strain probiotics on neonatal ward level.

Patients

Preterm infants documented by NEO-KISS, the German surveillance system for nosocomial infections in preterm infants with birth weights below 1,500 g, between 2004 and 2014.

Intervention

Routine use of dual-strain probiotics containing Lactobacillus acidophilus and Bifidobacterium spp. (Infloran) on the neonatal ward level.

Main outcome measures

Incidences of NEC, overall mortality, mortality following NEC and nosocomial BSI.

Results

Data from 10,890 preterm infants in 44 neonatal wards was included in this study. Incidences of NEC and BSI were 2.5% (n = 274) and 15.0%, (n = 1631), respectively. Mortality rate was 6.1% (n = 665). The use of dual-strain probiotics significantly reduced the risk of NEC (HR = 0.48; 95% CI = 0.38–0.62), overall mortality (HR = 0.60, 95% CI = 0.44–0.83), mortality after NEC (HR = 0.51, 95% CI = 0.26–0.999) and nosocomial BSI (HR = 0.89, 95% CI = 0.81–0.98). These effects were even more pronounced in the subgroup analysis of preterm infants with birth weights below 1,000 g.

Conclusion

In order to reduce NEC and mortality in preterm infants, it is advisable to add routine prophylaxis with dual-strain probiotics to clinical practice in neonatal wards.

[BRONCHOPULMONARY DYSPLASIA IN VERY LOW BIRTH WEIGHT INFANTS--THE OLD NEW PROBLEM]

BACKGROUND

The advances in perinatal intensive care have increased the survival rate of extremely low birthweight (ELBW) and gestational age infants. Among them the risk of developing bronchopulmonary dysplasia (BPD) remains high.

AIM

To evaluate the frequency of BPD by birthweight and gestational age, to identify the main postnatal risk factors and the associated comorbidities.

METHODS

683 VLBW infants (< 1500g) were admitted in NICU from 2008 to 2010. 597 survived more than 28 days and were included in this study. BPD was diagnosed if supplemental O2 for the first 28 days was necessary; the severity was assessed by the need of O2 and/or ventilator support at 36 gestational weeks (gw).

RESULTS

27.6% (n = 164) infants were with supplemental O2 at 28d of life (BPD-group), 10.9% (n = 65) were with moderate, 3.9% (n = 23) with severe BPD (FiO2 > 30% and/or ventilator support). Infants with BPD were with significantly higher CRIB (9.9 ± 3.1) compared with those without BPD (4.0 ± 3.0), p < 0.0001. The frequency decreased progressively from almost 100% at 23gw or birthweight < 600g to single cases after 31gw and bitthweight > 1200g. Logistic regression analysis showed that each gestational week decreased the odds of BPD by 60%; each CRIB point increased the odds by 62%. Each point increment in 1/5 min Apgar-scores reduced the risk by 40%/50% respectively The need for ventilator support increased from 1.4 ± 2.7 days (no-BPD group) to 52.8 ± 5.1 days (severe-BPD infants), p < 0.05. Postnatal complications significantly increasing the odds for BPD were found to be: PDA - 19.7, Pneumothorax - 12.1 times. There was a significant correlation between BPD, severe brain injury and ROP (p < 0.000 1).

CONCLUSION

The frequency of BPD strongly correlates with gestational age and birthweight and CRIB. Additional risk factors are low A pgar scores, PDA and air leak syndrome. Associated comorbidities as severe brain injury and ROP further worsen the long term prognosis.

Abnormal heart rate characteristics are associated with abnormal neuroimaging and outcomes in extremely low birth weight infants

OBJECTIVE

Brain injury in preterm infants may lead to an inflammatory response and central nervous system dysfunction reflected by abnormal heart rate characteristics (HRC). We hypothesized that a continuously monitored HRC index reflecting reduced HR variability and decelerations correlates with abnormal neuroimaging and outcomes in extremely low birth weight infants (ELBW).

STUDY DESIGN

We analyzed the average HRC index within 28 days after birth (aHRC28) and head ultrasound (HUS) in 384 ELBW infants. In 50 infants with brain magnetic resonance imaging (MRI) and 70 infants with Bayley neurodevelopmental testing at 1 year of age, we analyzed the relationship between aHRC28, MRI abnormalities and low Bayley scores.

RESULT

aHRC28 was higher in infants with severe HUS abnormalities (2.65±1.27 for Grade III-IV intraventricular hemorrhage (IVH) or cystic periventricular leukomalacia (cPVL) versus 1.72±0.95 for normal or Grade I-II IVH, P<0.001). Higher aHRC28 was also associated with white matter damage on MRI and death or Bayley motor or mental developmental index <70. Associations persisted after adjusting for gestational age, birth weight and septicemia. For every one point increase in aHRC28, the odds ratio of death or Bayley score <70 was 2.45 (95% CI 1.46, 4.05, P<0.001).

CONCLUSION

A continuously monitored HRC index provides an objective, noninvasive measure associated with abnormal brain imaging and adverse neurologic outcomes in ELBW infants.

Latent mean differences in executive function in at-risk preterm children: the delay-deficit dilemma

OBJECTIVE

To examine whether a one-factor executive function (EF) model fit data for three groups of children differing in birth criteria (extremely low birth weight [ELBW], late preterm [LPT], and Term) at each of two chronological ages, 3 and 6 years, and whether the latent mean amount of EF differed.

METHODS

A retrospective observational cohort study of 1,079 participants; 668 aged 3 years born 2000-2009 (93 ELBW, 398 LPT, and 177 Term) and 411 aged 6 years born 1998-2006 (126 ELBW, 102 LPT, and 183 Term). Latent means analysis was conducted using five indicators for EF: noun fluency, action-verb fluency, similarities reasoning, matrices reasoning, and working memory.

RESULTS

A one-factor model had acceptable fit for all groups (RMSEA<.06, CFI >0.95, SRMR <0.08). Statistically significant between-groups differences were found for all comparisons except one; there were no statistically significant differences between LPT-Term at age 6. At age 3, ELBW was 0.98 and 1.70 SD below LPT and Term, respectively; LPT was 0.61 SD below Term. At age 6, ELBW was 0.70 and 0.78 SD below LPT and Term, respectively; LPT was 0.10 SD below Term.

CONCLUSIONS

Executive deficit identified early in development after preterm birth could represent a transient developmental delay likely to resolve at older age or a more subtle adverse effect likely to persist over the life span. Study at multiple age points should assist in resolving this dilemma, which has important implications for early age neuropsychological screening and intervention.

Neonatal pain-related stress, functional cortical activity and visual-perceptual abilities in school-age children born at extremely low gestational age

Children born very prematurely (< or =32 weeks) often exhibit visual-perceptual difficulties at school-age, even in the absence of major neurological impairment. The alterations in functional brain activity that give rise to such problems, as well as the relationship between adverse neonatal experience and neurodevelopment, remain poorly understood. Repeated procedural pain-related stress during neonatal intensive care has been proposed to contribute to altered neurocognitive development in these children. Due to critical periods in the development of thalamocortical systems, the immature brain of infants born at extremely low gestational age (ELGA; < or =28 weeks) may have heightened vulnerability to neonatal pain. In a cohort of school-age children followed since birth we assessed relations between functional brain activity measured using magnetoencephalogragy (MEG), visual-perceptual abilities and cumulative neonatal pain. We demonstrated alterations in the spectral structure of spontaneous cortical oscillatory activity in ELGA children at school-age. Cumulative neonatal pain-related stress was associated with changes in background cortical rhythmicity in these children, and these alterations in spontaneous brain oscillations were negatively correlated with visual-perceptual abilities at school-age, and were not driven by potentially confounding neonatal variables. These findings provide the first evidence linking neonatal pain-related stress, the development of functional brain activity, and school-age cognitive outcome in these vulnerable children.

Human milk is the only milk for premies in the NICU!

Numerous short and long-term benefits of breastfeeding the full-term infant have been acknowledged. The use of human milk in the neonatal intensive care unit (NICU) is emerging as the beneficial effects are being realized. Challenges facing the practitioners today include providing optimal storage and processing strategies for mother's own milk (MOM), as well as offering an alternative when MOM is unavailable or supply is insufficient. We review the health benefits of human milk for the ELBW infant and the strategies for optimal use of the milk in the NICU.

A pilot study to examine maturation of body temperature control in preterm infants

OBJECTIVE

To test instrumentation and develop analytic models to use in a larger study to examine developmental trajectories of body temperature and peripheral perfusion from birth in extremely low-birth-weight (EBLW) infants.

DESIGN

A case study design.

SETTING

The study took place in a Level 4 neonatal intensive care unit (NICU) in North Carolina.

PARTICIPANTS

Four ELBW infants, fewer than 29 weeks gestational age at birth.

METHODS

Physiologic data were measured every minute for the first 5 days of life: peripheral perfusion using perfusion index by Masimo and body temperature using thermistors. Body temperature was also measured using infrared thermal imaging. Stimulation and care events were recorded over the first 5 days using video which was coded with Noldus Observer software. Novel analytical models using the state space approach to time-series analysis were developed to explore maturation of neural control over central and peripheral body temperature.

RESULTS/CONCLUSION

Results from this pilot study confirmed the feasibility of using multiple instruments to measure temperature and perfusion in ELBW infants. This approach added rich data to our case study design and set a clinical context with which to interpret longitudinal physiological data.

Permissive hypotension in extremely low birth weight infants (≤1000 gm)

PURPOSE

We performed this study to evaluate the safety of permissive hypotension management in extremely low birth weight infants (ELBWIs).

MATERIALS AND METHODS

Medical records of all inborn ELBWIs admitted to Samsung Medical Center from January 2004 to December 2008 were reviewed retrospectively. Of a total of 261 ELBWIs, 47 (18%) required treatment for hypotension (group T), 110 (42%) remained normotensive (group N), and 104 (40%) experienced more than one episode of hypotension without treatment (group P) during the first 72 hours of life. Treatment of hypotension included inotropic support and/or fluid loading.

RESULTS

Birth weight and Apgar scores were significantly lower in the T group than the other two groups. In the N group, the rate of pathologically confirmed maternal chorioamnionitis was significantly higher than other two groups, and the rate was higher in the P group than the T group. After adjusting for covariate factors, no significant differences in mortality and major morbidities were found between the N and P groups. However, the mortality rate and the incidence of intraventricular hemorrhage (≥stage 3) and bronchopulmonary dysplasia (≥moderate) were significantly higher in the T group than the other two groups. Long term neurodevelopmental outcomes were not significantly different between the N and P groups.

CONCLUSION

Close observation of hypotensive ELBWIs who showed good clinical perfusion signs without intervention allowed to avoid unnecessary medications and resulted in good neurological outcomes.

Beyond bacteria: a study of the enteric microbial consortium in extremely low birth weight infants

Extremely low birth weight (ELBW) infants have high morbidity and mortality, frequently due to invasive infections from bacteria, fungi, and viruses. The microbial communities present in the gastrointestinal tracts of preterm infants may serve as a reservoir for invasive organisms and remain poorly characterized. We used deep pyrosequencing to examine the gut-associated microbiome of 11 ELBW infants in the first postnatal month, with a first time determination of the eukaryote microbiota such as fungi and nematodes, including bacteria and viruses that have not been previously described. Among the fungi observed, Candida sp. and Clavispora sp. dominated the sequences, but a range of environmental molds were also observed. Surprisingly, seventy-one percent of the infant fecal samples tested contained ribosomal sequences corresponding to the parasitic organism Trichinella. Ribosomal DNA sequences for the roundworm symbiont Xenorhabdus accompanied these sequences in the infant with the greatest proportion of Trichinella sequences. When examining ribosomal DNA sequences in aggregate, Enterobacteriales, Pseudomonas, Staphylococcus, and Enterococcus were the most abundant bacterial taxa in a low diversity bacterial community (mean Shannon-Weaver Index of 1.02±0.69), with relatively little change within individual infants through time. To supplement the ribosomal sequence data, shotgun sequencing was performed on DNA from multiple displacement amplification (MDA) of total fecal genomic DNA from two infants. In addition to the organisms mentioned previously, the metagenome also revealed sequences for gram positive and gram negative bacteriophages, as well as human adenovirus C. Together, these data reveal surprising eukaryotic and viral microbial diversity in ELBW enteric microbiota dominated bytypes of bacteria known to cause invasive disease in these infants.

Early predictors of hypertension in prematurely born adolescents

OBJECTIVE

 To assess the blood pressure of former preterm and term matched adolescent controls and to identify risk factors associated with blood pressure at 16 years.

DESIGN

  Observational cohort study. Secondary analysis of a randomized clinical trial.

SETTING

Three academic centres participating in the Multicenter Indomethacin IVH Prevention Trial.

PARTICIPANTS

  A total of 296 children born in 1989-1992 with birth weights 600 to <1250 g who participated in the Multicenter Indomethacin IVH Prevention Trial and 95 term controls were evaluated at 16 years.

MAIN OUTCOME MEASURES

  Blood pressure and predictors of blood pressure.

RESULTS

  The adjusted mean difference in blood pressure for preterm adolescents was 5.1 mm Hg; p=0.002 for systolic and 2.1 mm Hg; p=0.027 for diastolic blood pressure. Among preterms, the primary predictors of increased systolic blood pressure were weight gain velocity between birth and 36 months (b=8.54, p<0.001), pre-eclampsia (b=5.67, p=0.020), non-white race (b=3.77, p=0.04) and male gender (b=5.09). Predictors of diastolic blood pressure were weight gain velocity between birth and 36 months (b=4.69, p=0.001), brain injury (b=6.51, p=0.002) and male gender (b=-2.4, p=0.02).

CONCLUSIONS

  Early programming secondary to increased early weight gain velocity, intrauterine stress and neonatal brain injury may all contribute to risk of increased blood pressure among former preterm adolescents.

Nutritional state, maturational delay on electroencephalogram, and developmental outcome in extremely low birth weight infants

The aim of this study is to clarify the relation among developmental outcome, nutritional state during the neonatal period, maturational electroencephalographic changes. Thirteen extremely low birth weight infants who completed 6- or 9-year follow-up were a subject of this study. Undernutrition was defined as enteral feeding below 100mL/kg/day at 3 weeks of age. Dysmature patterns were defined as the persistence of EEG patterns 2 weeks or more immature for post-conceptional age. IQ was examined at 6 and 9 years of age. Body height and weight, and head circumference at 6 years of age were stratified by the percentile grades. Full and verbal IQ was significantly lower in infants with undernutrition than those with normal nutrition. Among infants with undernutrition, those with persistent dysmature patterns tended to have lower full and performance IQ than those without persistent dysmature patterns. Head circumference was 50 percentile or larger in all infants with normal nutrition, whereas it was below 50 percentile in six of eight infants with undernutrition. Extremely low birth weight infants with undernutrition had worse neurodevelopmental outcome at 6 or 9 years of age than those with normal nutrition. Among infants with undernutrition, developmental outcome was relatively worse in those with persistent dysmature patterns than those without.

Growth hormone receptor d3-variant, insulin-like growth factor binding protein-1 -575G/A polymorphism and postnatal catch-up growth: association with parameters of glucose homeostasis in former extremely low birth weight preterm infants

BACKGROUND

Low birth weight predisposes to the development of insulin resistance. In addition to auxological parameters such as rapid catch-up growth, low IGFBP-1 serum levels in childhood have been linked to an increased risk of insulin resistance later in life. Concerning postnatal growth, we previously reported the GHRd3-variant to be associated with catch-up growth in preterm infants. In children born small for gestational age, a common IGFBP-1 promoter polymorphism -575G/A has been linked to IGFBP-1 serum levels and has been suggested to be an additional player in the interaction between the IGF-IGFBP-axis and metabolism.

STUDY DESIGN

We analyzed postnatal growth, metabolic parameters, and genotypes for the GHRd3-variant and IGFBP-1 -575G/A in 51 former extremely low birth weight preterm infants (mean age 5.9 years).

RESULTS

GHRd3 but not IGFBP-1 -575G/A was significantly associated with postnatal growth velocity. Catch-up growth, GHRd3, and IFGBP-1 -575G/A did not influence fasting insulin or HOMA-IR. However, we found significantly higher HbA1c and lower IGFBP-1 concentrations in GHRd3-carriers, a finding not seen with respect to IGFBP-1 -575G/A. Interestingly, HbA1c and IGFBP-1 levels also did not differ between children either with or without catch-up growth.

CONCLUSIONS

In addition to an association with catch-up growth, GHR exon 3 genotype significantly modulates HbA1c and IGFBP-1 concentrations in former ELBW infants. In order to confirm this observation and to clarify whether the GHRd3-variant might be considered as an independent modulator of the low birth weight infant's risk to develop insulin resistance later in life, larger studies extending to later ages are required.

The ELGAN study of the brain and related disorders in extremely low gestational age newborns

BACKGROUND

Extremely low gestational age newborns (ELGANs) are at increased risk for structural and functional brain abnormalities.

AIM

To identify factors that contribute to brain damage in ELGANs.

STUDY DESIGN

Multi-center cohort study.

SUBJECTS

We enrolled 1506 ELGANs born before 28 weeks gestation at 14 sites; 1201 (80%) survived to 2 years corrected age. Information about exposures and characteristics was collected by maternal interview, from chart review, microbiologic and histological examination of placentas, and measurement of proteins in umbilical cord and early postnatal blood spots.

OUTCOME MEASURES

Indicators of white matter damage, i.e. ventriculomegaly and echolucent lesions, on protocol cranial ultrasound scans; head circumference and developmental outcomes at 24 months adjusted age, i.e., cerebral palsy, mental and motor scales of the Bayley Scales of Infant Development, and a screen for autism spectrum disorders.

RESULTS

ELGAN Study publications thus far provide evidence that the following are associated with ultrasongraphically detected white matter damage, cerebral palsy, or both: preterm delivery attributed to preterm labor, prelabor premature rupture of membranes, or cervical insufficiency; recovery of microorganisms in the placenta parenchyma, including species categorized as human skin microflora; histological evidence of placental inflammation; lower gestational age at delivery; greater neonatal illness severity; severe chronic lung disease; neonatal bacteremia; and necrotizing enterocolitis.

CONCLUSIONS

In addition to supporting a potential role for many previously identified antecedents of brain damage in ELGANs, our study is the first to provide strong evidence that brain damage in extremely preterm infants is associated with microorganisms in placenta parenchyma.

EEG functional connectivity in term age extremely low birth weight infants

OBJECTIVE

The hypothesis is tested that electrocortical functional connectivity (quantified by coherence) of extremely low birth weight (ELBW) infants, measured at term post-menstrual age, has regional differences from that of full term infants.

METHODS

128 lead EEG data were collected during sleep from 8 ELBW infants with normal head ultrasound exams and 8 typically developing full term infants. Regional spectral power and coherence were calculated.

RESULTS

No significant regional differences in EEG power were found between infant groups. However, compared to term infants, ELBW infants had significantly reduced interhemispheric coherence (in frontal polar and parietal regions) and intrahemispheric coherence (between frontal polar and parieto-occipital regions) in the 1-12Hz band but increased interhemispheric coherence between occipital regions in the 24-50Hz band.

CONCLUSIONS

ELBW infants at term post-menstrual age manifest regional differences in EEG functional connectivity as compared to term infants.

SIGNIFICANCE

Distinctive spatial patterns of electrocortical synchrony are found in ELBW infants. These regional patterns may presage regional alterations in the structure of the cortex.

Transient anomalies in genital appearance in some extremely preterm female infants may be the result of foetal programming causing a surge in LH and the over activation of the pituitary-gonadal axis

AIM

Animal studies have linked foetal programming with the development of the polycystic ovarian syndrome, and metabolic syndrome, in adulthood. The objective is to describe the investigation of four extreme-premature female infants born between 25 and 29 weeks' gestation with apparent genital abnormalities in association with unusually high androgens and gonadotrophins, to postulate a cause and to raise awareness of pitfalls in assessment of these infants.

METHODS

Clinical examination and biochemical evaluation of four infants referred for apparent congenital ambiguity.

RESULTS

Female gender was assigned at birth. Chromosome analysis confirmed 46XX, urine steroid profiles demonstrated no evidence of congenital adrenal hyperplasia and only the expected levels of foetal adrenal steroids. Elevated LH (up to 162 IU/l), testosterone (up to 2.6 nmol/l), Delta(4 )androstenedione (up to > 35 nmol/l) and dehydro-epiandrosterone sulphate (DHEAS) (up to 26.6 micromol/l) were seen in all four infants. These decreased over time but were significantly different from a control population of premature infants of similar gestational age.

CONCLUSIONS

We postulate that the clinical pattern of apparent clitoral enlargement in some extremely premature infants may reflect true temporary virilization due to an unusually high (or excessive) LH surge, in turn causing high foetal androgens. Foetal programming of gonadotrophin excess is probably the primary cause of androgen increase, in turn causing virilization, in some extreme-premature infants. These may potentially be a group at future risk of polycystic ovary or metabolic syndrome, however, further work needs to be conducted to substantiate this hypothesis.

Predicting long-term visual outcome in children with birth weight under 1001 g

PURPOSE

To examine the visual acuity development of extremely low birth weight children and to determine factors that are predictive of long-term outcome.

METHODS

This is a prospective observational longitudinal cohort study of children with birth weight less than 1001 g. One hundred thirty-nine children were recruited. Retinopathy of prematurity (ROP) examinations were graded according to the International Classification for ROP. Grating acuity was assessed monocularly with Teller acuity cards. All children were assessed before 24 months corrected age; 123 of the cohort had a grating acuity assessment at over 3 years. For the children who were capable, an assessment of recognition acuity was measured with the Electronic Visual Acuity system.

RESULTS

Data are presented for the right eye and the ages reported are adjusted for prematurity to allow comparison with normative data. Initial grating acuity was compared with the late grating and recognition acuity, but in both cases analysis showed no statistically significant association. However, the relative risk analysis showed that, if the slope was abnormal, there was a 5.5 times higher risk of abnormal recognition acuity. Eyes with zone 1 disease were associated with a worse visual acuity outcome, but zone 1 disease also occurred more frequently in children with lower birth weight and gestational age.

CONCLUSIONS

Early measurements of visual acuity may be misleading in terms of the visual prognosis. The factor that was most predictive of a poor late visual acuity outcome was the rate of development, as calculated by the slope of the early visual acuity measurements.

Consensus statements on the borderlands of neonatal viability: from uncertainty to grey areas

The gestational age and birth weight cut off for intact survival in extremely preterm infants is unclear. There is uncertainty among obstetricians and neonatologists about when it is inadvisable to institute intensive care. The suggested definition in relation to viability is when mortality does not exceed 50% but the corresponding figure for disability is undetermined. On foot of these concerns many groups have produced consensus statements on viability over the past 15 years. In this paper we examine the findings in 7 consensus statements on viability- British Association of Perinatal Medicine, American Academy of Pediatrics, The Fetus and Newborn Committee Canada, The Dutch Group, The Australian Group, Nuffield Institute of Bioethics, Neonatal Section of the Irish Faculty of Paediatrics. A number of points of agreement emerge. All would provide intensive care at 26 weeks and most would not at 23 weeks. The grey area is 24 and 25 weeks gestation. This group of infants constitute 2 per 1000 births. The difficulty is that there are a number of confounding variables. Girls have approximately 1 week advantage over boys, every day increases survival by 3%, the benefits of a full course of antenatal steroids, the problem of multiple birth, the baby's condition at delivery. Also concerns have been expressed about basing policy on short-term follow-up only. Extreme prematurity is both uncommon and complex and should be managed in high volume tertiary centres that are familiar with the necessary facets for decision making.

Potassum and sodium homeostasis in the neonate

MANAGEMENT OF FLUIDS AND electrolytes is crucial when caring for the high-risk neonate. Fluid and electrolyte requirements vary with developmental limitations related to gestational age, as well as by the diagnosis or disease process involved. Management is further complicated by the physiologic contraction of extracellular water, and subsequent weight loss, that occurs during the first week after birth. Therefore, fluid and electrolyte balance requires meticulous assessment of both physiologic and clinical data in conjunction with laboratory data. Data to be followed include heart rate, blood pressure, skin turgor, capillary refill, mucus membranes, fullness of the anterior fontanel, daily (or more frequent) weights, intake and output, creatinine levels, and daily (or more frequent) serum electrolyte levels.1,2 Very low birth weight (VLBW) and extremely low birth weight (ELBW) infants may require an assessment of weight as often as three times a day and sampling of serum electrolytes as often as every four to eight hours.1

Effects of high versus standard early protein intake on growth of extremely low birth weight infants

OBJECTIVES

Early provision of protein has been shown to limit catabolism and could improve growth. Our objective was to determine whether early aggressive protein intake improved growth outcomes of extremely low birth weight (ELBW) infants.

PATIENTS AND METHODS

ELBW infants were included in the study if they had no major congenital anomalies or renal failure and were still hospitalized at 36 weeks postmenstrual age. In 25 infants (HP) the early protein intake was planned to be 20% greater than in 31 historical controls (SP).

RESULTS

The 2 groups were similar in the baseline characteristics. The mean protein intake during the first 14 days of life was significantly greater in the HP group (3.1 +/- 0.2 vs 2.5 +/- 0.2 g/kg/d; P<0.0001). HP group showed lower postnatal weight loss (-3.1%; 95% confidence interval [CI] -5.9, -0.2) and earlier regain of birth weight (-4.1 days; 95% CI -6.6, -1.7). Mean blood urea nitrogen and bicarbonate levels were similar; mean serum glucose level was lower in the HP group (-21,7 mg/dL; 95% CI -41.9,-1.5). HP infants had a reduced fall in weight z score (-0.57; 95% CI -1.01, -0.12) and in length z score (-0.51; 95% CI -0.97, -0.05) from birth to discharge.

CONCLUSION

Early high protein intake was associated with improved weight and length growth outcomes at discharge. These findings highlight the benefits of aggressive protein intake immediately after birth.

Randomized crossover comparison of proportional assist ventilation and patient-triggered ventilation in extremely low birth weight infants with evolving chronic lung disease

BACKGROUND

Refinement of ventilatory techniques remains a challenge given the persistence of chronic lung disease of preterm infants.

METHODS

To test the hypothesis that proportional assist ventilation (PAV) will allow to lower the ventilator pressure at equivalent fractions of inspiratory oxygen (FiO(2)) and arterial hemoglobin oxygen saturation in ventilator-dependent extremely low birth weight infants in comparison with standard patient-triggered ventilation (PTV).

DESIGN

Randomized crossover design.

SETTING

Two level-3 university perinatal centers.

PATIENTS

22 infants (mean (SD): birth weight, 705 g (215); gestational age, 25.6 weeks (2.0); age at study, 22.9 days (15.6)).

INTERVENTIONS

One 4-hour period of PAV was applied on each of 2 consecutive days and compared with epochs of standard PTV.

RESULTS

Mean airway pressure was 5.64 (SD, 0.81) cm H(2)O during PAV and 6.59 (SD, 1.26) cm H(2)O during PTV (p < 0.0001), the mean peak inspiratory pressure was 10.3 (SD, 2.48) cm H(2)O and 15.1 (SD, 3.64) cm H(2)O (p < 0.001), respectively. The FiO(2) (0.34 (0.13) vs. 0.34 (0.14)) and pulse oximetry readings were not significantly different. The incidence of arterial oxygen desaturations was not different (3.48 (3.2) vs. 3.34 (3.0) episodes/h) but desaturations lasted longer during PAV (2.60 (2.8) vs. 1.85 (2.2) min of desaturation/h, p = 0.049). PaCO(2) measured transcutaneously in a subgroup of 12 infants was similar. One infant met prespecified PAV failure criteria. No adverse events occurred during the 164 cumulative hours of PAV application.

CONCLUSIONS

PAV safely maintains gas exchange at lower mean airway pressures compared with PTV without adverse effects in this population. Backup conventional ventilation breaths must be provided to prevent apnea-related desaturations.

Long-term visual outcomes in extremely low-birth-weight children (an American Ophthalmological Society thesis)

PURPOSE

The goal is to analyze the long-term visual outcome of extremely low-birth-weight children.

METHODS

This is a retrospective analysis of eyes of extremely low-birth-weight children on whom vision testing was performed. Visual outcomes were studied by analyzing acuity outcomes at >/=36 months of adjusted age, correlating early acuity testing with final visual outcome and evaluating adverse risk factors for vision.

RESULTS

Data from 278 eyes are included. Mean birth weight was 731g, and mean gestational age at birth was 26 weeks. 248 eyes had grating acuity outcomes measured at 73 +/- 36 months, and 183 eyes had recognition acuity testing at 76 +/- 39 months. 54% had below normal grating acuities, and 66% had below normal recognition acuities. 27% of grating outcomes and 17% of recognition outcomes were /=3 years of age. A slower-than-normal rate of early visual development was predictive of abnormal grating acuity (P < .0001) and abnormal recognition acuity (P < .0001) at >/=3 years of age. Eyes diagnosed with maximal retinopathy of prematurity in zone I had lower acuity outcomes (P = .0002) than did those with maximal retinopathy of prematurity in zone II/III. Eyes of children born at 28 weeks gestational age. Eyes of children with poorer general health after premature birth had a 5.3 times greater risk of abnormal recognition acuity.

CONCLUSIONS

Long-term visual development in extremely low-birth-weight infants is problematic and associated with a high risk of subnormal acuity. Early acuity testing is useful in identifying children at greatest risk for long-term visual abnormalities. Gestational age at birth of Collapse

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MESH Headings

• Birth Weight
• Child
• Child, Preschool
• Follow-Up Studies
• Gestational Age
• Humans
• Infant, Extremely Low Birth Weight/physiology
• Infant, Newborn
• Ocular Physiological Phenomena
• Predictive Value of Tests
• Retinopathy of Prematurity/physiopathology
• Retrospective Studies
• Risk Factors
• Vision Disorders/physiopathology
• Vision Tests/methods
• Visual Acuity/physiology

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Affiliation(s)

Rand Spencer Texas Retina Associates, Retina Foundation of the Southwest and Department of Ophthalmology, University of Texas Southwestern Medical School, Dallas, Texas, USA

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