Severe bronchopulmonary dysplasia increases risk for later neurological and motor sequelae in preterm survivors

Efficacy of inhaled nitric oxide in preterm infants ≤ 34 weeks: a systematic review and meta-analysis of randomized controlled trials

Background: The effect of inhaled nitric oxide (iNO) in neonates >34 weeks on improving respiration is well documented. However, the efficacy of iNO in preterm infants ≤34 weeks remains controversial. Objectives: The main purpose of this review is to assess the effectiveness and safety of iNO treatment in preterm infants ≤34 weeks. Search methods: We systematically searched PubMed, Embase and Cochrane Libraries from their inception to 1 June 2023. We also reviewed the reference lists of retrieved studies. Selection criteria: Our study involved randomized controlled trials on preterm infants ≤34 weeks, especially those receiving iNO treatment, and mainly assessed outcomes such as bronchopulmonary dysplasia (BPD) and mortality. Two authors independently reviewed these trials, extracted data, and evaluated study biases. Disagreements were resolved by consensus. We used the GRADE method to assess evidence quality. Results: Our research included a total of 17 studies involving 4,080 neonates and 7 follow-up studies. The synthesis of results showed that in neonates, iNO treatment reduced the incidence of BPD (RR: 0.92; 95% CI: 0.86-0.98). It also decreased the composite outcome of death or BPD (RR: 0.94; 95% CI: 0.90-0.98), without increasing the risk of short-term (such as intraventricular hemorrhage, periventricular leukomalacia) and long-term neurological outcomes (including Bayley mental developmental index <70, cerebral palsy and neurodevelopmental impairment). Furthermore, iNO did not significantly affect other neonatal complications like sepsis, pulmonary hemorrhage, necrotizing enterocolitis, and symptomatic patent ductus arteriosus. Subgroup analysis revealed that iNO significantly reduced BPD incidence in neonates at 36 weeks under specific intervention conditions, including age less than 3 days, birth weight over 1,000 g, iNO dose of 10 ppm or higher, or treatment duration exceeding 7 days (p < 0.05). Conclusion: Inhaled NO reduced the incidence of BPD in neonates at 36 weeks of gestation, and the effect of the treatment depended on neonatal age, birth weight, duration and dose of iNO. Therefore, iNO can be considered a promising treatment for the potential prevention of BPD in premature infants. More data, however, would be needed to support nitric oxide registration in this specific patient population, to minimize its off-label use.

Complex roles of TGF-β signaling pathways in lung development and bronchopulmonary dysplasia

As survival of extremely preterm infants continues to improve, there is also an associated increase in bronchopulmonary dysplasia (BPD), one of the most significant complications of preterm birth. BPD development is multifactorial resulting from exposure to multiple antenatal and postnatal stressors. BPD has both short-term health implications and long-term sequelae including increased respiratory, cardiovascular, and neurological morbidity. Transforming growth factor β (TGF-β) is an important signaling pathway in lung development, organ injury, and fibrosis and is implicated in the development of BPD. This review provides a detailed account on the role of TGF-β in antenatal and postnatal lung development, the effect of known risk factors for BPD on the TGF-β signaling pathway, and how medications currently in use or under development, for the prevention or treatment of BPD, affect TGF-β signaling.

Machine learning for prediction of bronchopulmonary dysplasia-free survival among very preterm infants

Background

Bronchopulmonary dysplasia (BPD) is one of the most common and serious sequelae of prematurity. Prompt diagnosis using prediction tools is crucial for early intervention and prevention of further adverse effects. This study aims to develop a BPD-free survival prediction tool based on the concept of the developmental origin of BPD with machine learning.

Methods

Datasets comprising perinatal factors and early postnatal respiratory support were used for initial model development, followed by combining the two models into a final ensemble model using logistic regression. Simulation of clinical scenarios was performed.

Results

Data from 689 infants were included in the study. We randomly selected data from 80% of infants for model development and used the remaining 20% for validation. The performance of the final model was assessed by receiver operating characteristics which showed 0.921 (95% CI: 0.899–0.943) and 0.899 (95% CI: 0.848–0.949) for the training and the validation datasets, respectively. Simulation data suggests that extubating to CPAP is superior to NIPPV in BPD-free survival. Additionally, successful extubation may be defined as no reintubation for 9 days following initial extubation.

Conclusions

Machine learning-based BPD prediction based on perinatal features and respiratory data may have clinical applicability to promote early targeted intervention in high-risk infants.

Early High-Dose Caffeine Improves Respiratory Outcomes in Preterm Infants

The objective of the study is to determine if early high-dose caffeine (HD) therapy is associated with shorter duration of mechanical ventilation, bronchopulmonary dysplasia (BPD), or decreased need for mechanical ventilation. We conducted a single center, retrospective cohort study of 273 infants less than 32 weeks gestational age (GA). Infants receiving early HD (10 mg/kg/day maintenance) caffeine citrate started within 24 h of life were compared with those receiving LD (6 mg/kg/day) with variable timing of initiation using linear and logistic regression models. The infants in the early HD group had 91.4 (95% confidence interval (CI): −166.6, −16.1; p = 0.018) less hours of mechanical ventilation up to 36 weeks PMA or discharge as compared with the LD group. Moreover, infants in the HD group had 0.37 (95% CI: 0.14, 0.97; p = 0.042) times lower odds of developing moderate/severe BPD compared with the LD group. Infants receiving early HD caffeine had improved respiratory outcomes with no increase in measured comorbidities. Large prospective studies are needed to determine the long-term outcomes of using high-dose caffeine prophylaxis for preterm infants.

Short- and long-term outcomes of very low birth weight infants in Korea: Korean Neonatal Network update in 2019

Korea currently has the world's lowest birth rate but a rapidly inreasing number of preterm infants. The Korean Neonatal Network (KNN), launched by the Korean Society of Neonatology under the support of Korea Centers for Disease Control, has collected population-based data for very low birth weight infants (VLBWIs) born in Korea since 2013. In terms of the short-term outcomes of VLBWIs born from 2013 to 2016 registered in the KNN, the survival rate of all VLBWIs was 86%. Respiratory distress syndrome and bronchopulmonary dysplasia were observed in 78% and 30% of all VLBWIs, respectively. Necrotizing enterocolitis occurred in 7%, while 8% of the VLBWIs needed therapy for retinopathy of prematurity in the neonatal intensive care unit (NICU). Sepsis occurred in 21% during their NICU stay. Intraventricular hemorrhage (grade ≥III) was diagnosed in 10%. In terms of the long-term outcomes for VLBWIs born from 2013 to 2014 registered in the KNN, the post-discharge mortality rate was approximately 1.2%-1.5%, mainly owing to their underlying illness. Nearly half of the VLBWIs were readmitted to the hospital at least once in their first 1-2 years of life, mostly as a result of respiratory diseases. The overall prevalence of cerebral palsy was 6.2%-6.6% in Korea. Bilateral blindness was reported in 0.2%-0.3% of VLBWIs, while bilateral hearing loss was found in 0.8%-1.9%. Since its establishment, the KNN has published annual reports and papers that facilitate the improvement of VLBWI outcome and the formulation of essential healthcare policies in Korea.

Impact of tracheostomy on language and cognitive development in infants with severe bronchopulmonary dysplasia

OBJECTIVE

The impact of tracheostomy on language and cognitive development in infants with severe bronchopulmonary dysplasia (BPD) is not known. We hypothesize that tracheostomy has an independent negative impact on language and cognitive development in infants with severe BPD.

STUDY DESIGN

This is a retrospective cohort study of de-identified data of infants with severe BPD who received tracheostomy at <2 years of age, compared with infants with severe BPD without tracheostomy. The primary outcomes measured were total language and cognitive scores at 2-3 years of age as determined by Bayley Scales of Infant and Toddler Development, 3rd Edition.

RESULTS

A total of 26 patients with tracheostomies and 28 patients without tracheostomies were analyzed. There was no significant difference in total language development or cognitive development between patients with tracheostomies and those without. Insurance status had an effect on language and cognition while controlling for trach status.

CONCLUSIONS

Tracheostomy does not independently impact the language and cognitive development of infants with severe BPD.

Retinopathy of Prematurity and Bronchopulmonary Dysplasia are Independent Antecedents of Cortical Maturational Abnormalities in Very Preterm Infants

Very preterm (VPT) infants are at high-risk for neurodevelopmental impairments, however there are few validated biomarkers at term-equivalent age that accurately measure abnormal brain development and predict future impairments. Our objectives were to quantify and contrast cortical features between full-term and VPT infants at term and to associate two key antecedent risk factors, bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP), with cortical maturational changes in VPT infants. We prospectively enrolled a population-based cohort of 110 VPT infants (gestational age ≤31 weeks) and 51 healthy full-term infants (gestational age 38-42 weeks). Structural brain MRI was performed at term. 94 VPT infants and 46 full-term infants with high-quality T2-weighted MRI were analyzed. As compared to full-term infants, VPT infants exhibited significant global cortical maturational abnormalities, including reduced surface area (-5.9%) and gyrification (-6.7%) and increased curvature (5.9%). In multivariable regression controlled for important covariates, BPD was significantly negatively correlated with lobar and global cortical surface area and ROP was significantly negatively correlated with lobar and global sulcal depth in VPT infants. Our cohort of VPT infants exhibited widespread cortical maturation abnormalities by term-equivalent age that were in part anteceded by two of the most potent neonatal diseases, BPD and ROP.

Home Oxygen and 2-Year Outcomes of Preterm Infants With Bronchopulmonary Dysplasia

OBJECTIVES

To compare medical and developmental outcomes over the first 2 years of life in extremely preterm infants with bronchopulmonary dysplasia (BPD) who were discharged on supplemental oxygen via nasal cannula with outcomes of infants with a similar severity of respiratory illness who were discharged breathing in room air.

METHODS

We performed a propensity score-matched cohort study. Eligible infants were born at <27 weeks' gestation, were receiving supplemental oxygen or respiratory support at 36 weeks' postmenstrual age, and were assessed at 18 to 26 months' corrected age. Study outcomes included growth, resource use, and neurodevelopment between discharge and follow-up. Outcomes were compared by using multivariable models adjusted for center and age at follow-up.

RESULTS

A total of 1039 infants discharged on supplemental oxygen were propensity score matched 1:1 to infants discharged breathing in room air. Infants on oxygen had a marginal improvement in weight z score (adjusted mean difference 0.11; 95% confidence interval [CI] 0.00 to 0.22), with a significantly improved weight-for-length z score (adjusted mean difference 0.13; 95% CI 0.06 to 0.20) at 22 to 26 months' corrected age. Infants on oxygen were more likely to be rehospitalized for respiratory illness (adjusted relative risk 1.33; 95% CI 1.16 to 1.53) and more likely to use respiratory medications and equipment. Rates of neurodevelopmental impairment were similar between the groups.

CONCLUSIONS

In this matched cohort of infants with BPD, postdischarge oxygen was associated with marginally improved growth and increased resource use but no difference in neurodevelopmental outcomes. Ongoing and future trials are critical to assess the efficacy and safety of postdischarge supplemental oxygen for infants with BPD.

Neonatal Outcomes of Very Low Birth Weight Infants in Korean Neonatal Network from 2013 to 2016

BACKGROUND

This study was performed to determine survival and morbidity rates in very low birth weight infants (VLBWIs) in the Korean Neonatal Network (KNN), and to compare neonatal outcomes with those in other countries.

METHODS

Data were collected for 8,269 VLBWIs with gestational age (GA) ≥ 22 weeks who were born between January 1, 2013 and December 31, 2016, and admitted to the neonatal intensive care units of the KNN.

RESULTS

The survival rate of all VLBWIs and of infants with GA 22-23, 24-25, 26-27, 28-29, 30-32, and > 32 weeks were 86% (total), 33%, 65%, 84%, 94%, 97%, and 98%, respectively. The bronchopulmonary dysplasia (BPD) rates of all VLBWIs and of infants with GA 22-23, 24-25, 26-27, 28-29, 30-32, and > 32 weeks were 30% (total), 88%, 64%, 47%, 26%, 14%, and 5%, respectively. The intraventricular hemorrhage rates (≥ grade III) of all VLBWIs and of infants with GA 22-23, 24-25, 26-27, 28-29, 30-32, and > 32 weeks were 10% (total), 45%, 27%, 12%, 5%, 2%, and 1%, respectively. In an international comparison, the survival rate of VLBWIs with GA 24-27 weeks in KNN was lower, and the BPD rate of VLBWIs in the KNN was higher than that of the neonatal networks of other countries.

CONCLUSION

Despite overall improvements in neonatal outcomes, the survival and morbidity rates of more immature infants with GA 22-27 weeks need further improvement. Therefore, it would be necessary to develop more optimal treatment strategies and perform more active quality improvement to further improve neonatal outcomes of VLBWIs in Korea.

Components of the antepartum, intrapartum, and postpartum exposome impact on distinct short-term adverse neonatal outcomes of premature infants: A prospective cohort study

We aimed to test the hypothesis that determinants of the perinatal clinical exposome related to the underlying etiology of premature birth (PTB) impact differently on select neonatal outcomes. We conducted a prospective longitudinal study of 377 singleton preterm neonates [gestational age (GA) at birth: 23-34 weeks] separated into three distinct contemporaneous newborn cohorts: i) spontaneous PTB in the setting of intra-amniotic infection/inflammation (yes-IAI, n = 116); ii) spontaneous PTB in the absence of IAI (no-IAI, n = 130), and iii) iatrogenic PTB for preeclampsia (iPTB-PE, n = 131). Newborns (n = 372) were followed until death or discharge. Amniotic fluid defensins 1&2 and calgranulins A&C were used as biomarkers of IAI. An algorithm considering cord blood interleukin-6 (IL-6) and haptoglobin (Hp switch-on) was used to assess fetal exposure to IAI. Intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), early-onset neonatal (EONS) and late-onset (LOS) sepsis, death. Independent risk factors for adverse outcomes were: i) IVH (n = 53): histologic chorioamnionitis, GA, fetal growth restriction, male sex, Hp switch-on; ii) PVL (n = 11): cord blood IL-6; iii) NEC (n = 25), GA; iv) BPD (n = 53): ventilator support, need for surfactant, GA; v) ROP (n = 79): ventilator support, Hp switch-on, GA; vi) fetal and neonatal death (n = 31): GA, amniotic fluid IL-6; vii) suspect EONS (n = 92): GA, Hp switch-on; viii) LOS (n = 81): GA. Our findings are applicable to pregnancies delivered between 23 and 34 weeks' gestation in the setting of IAI and PE, and suggest that GA and inflammatory intrauterine environment play key roles in occurrence of IVH, PVL, ROP, death, EONS and LOS. Postnatal determinants seem to play major role in NEC and BPD.

First-In-Human Administration of Allogeneic Amnion Cells in Premature Infants With Bronchopulmonary Dysplasia: A Safety Study

Bronchopulmonary dysplasia (BPD) is a chronic lung disease that mainly affects premature babies who require ventilator support. The pathogenesis of BPD is complex but includes vascular maldevelopment, alveolarization arrest, and lung inflammation. There is no cure for BPD. Clinical care is limited to supportive respiratory measures. A population of stem-like cells derived from placental membranes, human amnion epithelial cells (hAECs), has shown therapeutic promise in preclinical models of BPD. With a view to future efficacy trials, we undertook a first-in-human clinical trial of hAECs in babies with BPD to assess the safety of these cells. In a single-center, open-label phase I trial, we administered allogeneic hAECs (1 × 10⁶ per kilogram bodyweight) by intravenous infusion to six premature babies with BPD. The primary outcomes of the study were focused on safety, including local site reaction, anaphylaxis, infection, features of rejection, or tumor formation. Outcomes to discharge from neonatal unit were studied. The hAECs were well tolerated. In the first baby, there was transient cardiorespiratory compromise during cell administration consistent with a pulmonary embolic event. Following changes to cell administration methods, including introduction of an inline filter, and reducing the cell concentration and the rate of cell infusion, no such events were observed in the subsequent five babies. We did not see evidence of any other adverse events related to cell administration. Allogeneic hAECs can be safely infused into babies with established BPD. Future randomized clinical trials to assess efficacy in this patient population are justified. Stem Cells Translational Medicine 2018;7:628-635.

Cognitive Development and Quality of Life Associated With BPD in 10-Year-Olds Born Preterm

OBJECTIVES

To compare neurocognitive, language, executive function, academic achievement, neurologic and behavioral outcomes, and quality of life at age 10 years in children born extremely preterm who developed bronchopulmonary dysplasia (BPD) to children who did not develop BPD.

METHODS

The Extremely Low Gestational Age Newborns study population included 863 children born extremely preterm whose BPD status before discharge was known had an IQ (Differential Ability Scales II [DAS II]) assessment at 10 years. We evaluated the association of BPD with any cognitive (DAS II), executive function (NEuroPSYchological Assessment II), academic achievement (Wechsler Individual Achievement Test-III and Oral and Written Language Scales [OWLS]) as well as social dysfunctions (Social Responsiveness Scale). We used logistic regression models, adjusting for potential confounding factors, to assess the strength of association between the severity of BPD and each outcomes.

RESULTS

Three hundred and seventy-two (43%) children were oxygen-dependent at 36 weeks postconception age, whereas an additional 78 (9%) were also oxygen- and ventilator-dependent. IQ scores 2 or more SDs below the expected mean (ie, z scores ≤-2) occurred twice as commonly among children who had BPD as among those who did not. Children with severe BPD consistently had the lowest scores on DAS II, OWLS, Wechsler Individual Achievement Test-III, NEuroPSYchological Assessment II, and Social Responsiveness Scale assessments.

CONCLUSIONS

Among 10-year-old children born extremely preterm, those who had BPD were at increased risk of cognitive, language, and executive dysfunctions; academic achievement limitations; social skill deficits; and low scores on assessments of health-related quality of life.

Recent Changes in the Incidence of Bronchopulmonary Dysplasia among Very-Low-Birth-Weight Infants in Korea

We investigated the incidence of bronchopulmonary dysplasia (BPD) in very-low-birth-weight (VLBW) infants in Korea using the Korean Neonatal Network (KNN) data. In total, 2,386 VLBW infants born from January 2013 to June 2014 were prospectively registered. BPD was defined as supplemental oxygen or positive pressure support at 36 weeks postmenstrual age (PMA). The overall incidence of BPD was 28.9%, and the overall mortality rate in the neonatal intensive care units (NICUs) was 11.9%. To investigate recent changes in the incidence of BPD among VLBW infants, we compared the BPD rate in the present study with the latest nationwide retrospective survey conducted between 2007 and 2008. For comparison, we selected infants (23-31 weeks of gestation) (n=1,990) to adjust for the same conditions with the previous survey in 2007-2008 (n=3,841). Among the limited data on VLBW infants (23-31 weeks of gestation), the incidence of BPD increased by 85% (from 17.8% to 33.0%) and the mortality rate in the NICU decreased by 31.4% (from 18.8% to 12.9%) compared to those in the study conducted in 2007-2008. The current trend of increase in the incidence of BPD among infants can be attributed to the increase in the survival rate of VLBW infants.

Need for supplemental oxygen at discharge in infants with bronchopulmonary dysplasia is not associated with worse neurodevelopmental outcomes at 3 years corrected age

OBJECTIVES

To determine if chronic oxygen dependency (discharge home on supplemental oxygen) in children with bronchopulmonary dysplasia (BPD; defined as requirement for supplemental O2 at 36 weeks postmenstrual age) predicts neurodevelopmental disability rates and growth outcomes at 36 months corrected age (CA).

STUDY DESIGN

Longitudinal cohort study.

SETTING

Southern Alberta regional center located at high altitude.

PARTICIPANTS

Preterm infants weighing ≤1250 grams with no BPD, BPD, and BPD with chronic oxygen dependency.

MAIN OUTCOME MEASURES

Neurodevelopmental and growth outcomes.

RESULTS

Of 1563 preterm infants admitted from 1995-2007, 1212 survived. Complete follow-up data were available for 1030 (85%) children. Children in BPD and BPD with chronic oxygen dependency groups had significantly lower birth weights, gestational ages, prolonged mechanical ventilation and oxygen supplementation and received more postnatal steroids, compared to those without BPD. Children with BPD and BPD with chronic oxygen dependency were more likely to be below the 5th centile in weight and height compared to those without BPD but there was little difference between the BPD and BPD with chronic oxygen dependency groups. After controlling for confounding variables, children who had BPD and BPD with chronic oxygen dependency had higher odds of neurodevelopmental disability compared to those without BPD [OR (odds ratio) 1.9 (95%CI 1.1 to 3.5) and OR 1.8 (1.1 to 2.9), respectively], with no significant difference between BPD and BPD with chronic oxygen dependency [OR 0.9 (95% CI 0.6 to 1.5)].

CONCLUSIONS

BPD and BPD with chronic oxygen dependency in children predicts abnormal neurodevelopmental outcomes at 36 months CA. However, the neurodevelopmental disability rates were not significantly higher in BPD with chronic oxygen dependency children compared to children with BPD only. Compared to those without BPD, growth is impaired in children with BPD and BPD with chronic oxygen dependency, but no difference between the latter two groups.

Epidemiology of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is among the most common and serious sequelae of preterm birth. BPD affects at least one-quarter of infants born with birth weights less than 1500 g. The incidence of BPD increases with decreasing gestational age and birth weight. Additional important risk factors include intrauterine growth restriction, sepsis, and prolonged exposure to mechanical ventilation and supplemental oxygen. The diagnosis of BPD predicts multiple adverse outcomes including chronic respiratory impairment and neurodevelopmental delay. This review summarizes the diagnostic criteria, incidence, risk factors, and long-term outcomes of BPD.

Development of fine motor skills in preterm infants

Fine motor skills are related to functioning in daily life and at school. We reviewed the status of knowledge, in preterm children, on the development of fine motor skills, the relation with gross motor skills, and risk factors for impaired fine motor skills. We searched the past 15 years in PubMed, using ['motor skills' or 'fine motor function' and 'preterm infant'] as the search string. Impaired gross and fine motor skills are among the most frequently occurring problems encountered by preterm children who do not develop cerebral palsy. The prevalence is around 40% for mild to moderate impairment and 20% for moderate impairment. Fine motor skill scores on the Movement Assessment Battery for Children are about 0.62 of a standard deviation lower compared with term children. Risk factors for fine motor impairments include moderately preterm birth (odds ratio [OR] 2.0) and, among very preterm children (<32 wk gestation), intra-uterine growth restriction (ORs 2-3), inflammatory conditions (late-onset sepsis and necrotizing enterocolitis, ORs 3-5), and dexamethasone therapy for bronchopulmonary dysplasia (OR 2.7). A better understanding of factors that play a role in the development of and recovery from brain injury could guide future intervention attempts aimed at improving fine motor skills of preterm children.

Curcumin protects the developing lung against long-term hyperoxic injury

Curcumin, a potent anti-inflammatory and antioxidant agent, modulates peroxisome proliferator-activated receptor-γ signaling, a key molecule in the etiology of bronchopulmonary dysplasia (BPD). We have previously shown curcumin's acute protection against neonatal hyperoxia-induced lung injury. However, its longer-term protection against BPD is not known. Hypothesizing that concurrent treatment with curcumin protects the developing lung against hyperoxia-induced lung injury long-term, we determined if curcumin protects against hyperoxic neonatal rat lung injury for the first 5 days of life, as determined at postnatal day (PND) 21. One-day-old rat pups were exposed to either 21 or 95% O₂ for 5 days with or without curcumin treatment (5 mg/kg) administered intraperitoneally one time daily, following which the pups grew up to PND21 in room air. At PND21 lung development was determined, including gross and cellular structural and functional effects, and molecular mediators of inflammatory injury. To gain mechanistic insights, embryonic day 19 fetal rat lung fibroblasts were examined for markers of apoptosis and MAP kinase activation following in vitro exposure to hyperoxia for 24 h in the presence or absence of curcumin (5 μM). Curcumin effectively blocked hyperoxia-induced lung injury based on systematic analysis of markers for lung injury (apoptosis, Bcl-2/Bax, collagen III, fibronectin, vimentin, calponin, and elastin-related genes) and lung morphology (radial alveolar count and alveolar septal thickness). Mechanistically, curcumin prevented the hyperoxia-induced increases in cleaved caspase-3 and the phosphorylation of Erk1/2. Molecular effects of curcumin, both structural and cytoprotective, suggest that its actions against hyperoxia-induced lung injury are mediated via Erk1/2 activation and that it is a potential intervention against BPD.

Score for neonatal acute physiology-II and neonatal pain predict corticospinal tract development in premature newborns

Premature infants are at risk for adverse motor outcomes, including cerebral palsy and developmental coordination disorder. The purpose of this study was to examine the relationship of antenatal, perinatal, and postnatal risk factors for abnormal development of the corticospinal tract, the major voluntary motor pathway, during the neonatal period. In a prospective cohort study, 126 premature neonates (24-32 weeks' gestational age) underwent serial brain imaging near birth and at term-equivalent age. With diffusion tensor tractography, mean diffusivity and fractional anisotropy of the corticospinal tract were measured to reflect microstructural development. Generalized estimating equation models examined associations of risk factors on corticospinal tract development. The perinatal risk factor of greater early illness severity (as measured by the Score for Neonatal Acute Physiology-II [SNAP-II]) was associated with a slower rise in fractional anisotropy of the corticospinal tract (P = 0.02), even after correcting for gestational age at birth and postnatal risk factors (P = 0.009). Consistent with previous findings, neonatal pain adjusted for morphine and postnatal infection were also associated with a slower rise in fractional anisotropy of the corticospinal tract (P = 0.03 and 0.02, respectively). Lessening illness severity in the first hours of life might offer potential to improve motor pathway development in premature newborns.

Early neurodevelopment in very low birth weight infants with mild intraventricular hemorrhage or those without intraventricular hemorrhage

PURPOSE

This study aimed to assess early development in very low birth weight (VLBW) infants with mild intraventricular hemorrhage (IVH) or those without IVH and to identify the perinatal morbidities affecting early neurodevelopmental outcome.

METHODS

Bayley Scales of Infant Development-II was used for assessing neurological development in 49 infants with a birth weight <1,500 g and with low grade IVH (≤grade II) or those without IVH at a corrected age of 12 months.

RESULTS

Among the 49 infants, 19 infants (38.8%) showed normal development and 14 (28.6%) showed abnormal mental and psychomotor development. Infants with abnormal mental development (n=14) were mostly male and had a longer hospitalization, a higher prevalence of patent ductus arteriosus (PDA) and bronchopulmonary dysplasia (BPD), and were under more frequent postnatal systemic steroid treatment compared with infants with normal mental development (n=35, P<0.05). Infants with abnormal psychomotor development (n=29) had a longer hospitalization and more associated PDA compared to infants with normal psychomotor development (n=20, P<0.05). Infants with abnormal mental and psychomotor development were mostly male and had a longer hospitalization and a higher prevalence of PDA and BPD compared to infants with normal mental and psychomotor development (n=19, P<0.05). Using multiple logistic regression analysis, a longer duration of hospitalization and male gender were found to be significant risk factors.

CONCLUSION

Approximately 62% of VLBW infants with low grade IVH or those without IVH had impaired early development.

Comparison of functional status of 8- to 12-year-old children born prematurely: an integrative review of literature

Prematurity affects one in eight infants in the United States, a rate that reflects an overall increase of 20% between 1990 and 2005 (March of Dimes, 2008). This integrative review presents a synthesis of the current research addressing the functional status of 8- to 12-year-old children born prematurely. Findings from this review support the belief that children born prematurely function differently than their term peers. These children have academic and social delays that may necessitate special service support through middle childhood.

Definition and outpatient management of the very low-birth-weight infant with bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD), also known as chronic lung disease of prematurity, is the major cause of pulmonary disease in infants. The pathophysiology and management of BPD have evolved over the past four decades as improved neonatal intensive care unit (NICU) modalities have increased survival rates. The likelihood for developing BPD increases with the degree of prematurity and reaches 25-35% in very low-birth-weight and extremely low-birth-weight infants. BPD affects many organ systems, and infants with BPD are at increased risk for rehospitalization and numerous complications following NICU discharge. The management of BPD and medically related problems, particularly during the first 2 years of life, remains a continuing challenge for parents and healthcare providers. It is important that a multidisciplinary team consisting of the neonatologist/attending physician, primary care physician, and other specialized support staff work in concert and meet regularly to provide continuity of care and accurate patient assessments.

Intratracheal Clara cell secretory protein (CCSP) administration in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Clara cell secretary protein (CCSP) is an immune-modulating and anti-inflammatory agent. CCSP is available synthetically as recombinant human Clara cell protein (rhCC10). It has been shown in animal models to reduce lung injury, improve pulmonary compliance and oxygenation, decrease systemic inflammation and up-regulate surfactant protein and vascular endothelial growth factor expression. These properties makes intratracheally administered CCSP a potential agent in prevention of chronic lung disease (CLD).

OBJECTIVES

To determine the effect of intratracheal CCSP administration compared to placebo or no treatment on morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome (RDS).

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library, October 2010), MEDLINE and PREMEDLINE (1950 to October 2010), EMBASE (1980 to October 2010) and CINAHL (1982 to October 2010). We searched proceedings of scientific meetings, Google Scholar and reference lists of identified studies, and contacted expert informants and surfactant manufacturers.

SELECTION CRITERIA

Published, unpublished and ongoing randomised controlled, cluster-randomised or quasi-randomised trials of intratracheal CCSP administration, compared to placebo or no treatment on morbidity and mortality in preterm infants at risk of RDS.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and quality, and extracted data.

MAIN RESULTS

One pilot study was identified and included. This study enrolled 22 preterm infants 700 to 1300g with established RDS who required ventilation for surfactant administration. Infants received one intratracheal dose of placebo (n = 7), 1.5 mg/kg (n = 8) or 5 mg/kg (n = 7) rhCC10 within four hours of surfactant treatment. At either dose of rhCC10, no significant difference was reported in CLD (36 weeks postmenstrual age or 28 days), mortality, intraventricular haemorrhage, periventricular leukomalacia, patent ductus arteriosus, necrotising enterocolitis, sepsis or days supplemental oxygen compared to placebo. A significant increase in days mechanical ventilation was reported for infants receiving rhCC10 5mg/kg (mean difference 12.00, 95% confidence interval 0.39 to 23.61) but not at the lower dose. The study reported that a single intratracheal dose of rhCC10 was well tolerated and resulted in a significant reduction in tracheal aspirate neutrophil and total cell count, and lung protein concentration. There was no significant difference reported in tracheal aspirate cytokine levels between groups.

AUTHORS' CONCLUSIONS

There are insufficient data to determine the role of rhCC10 in clinical practice. Further studies are required to determine if rhCC10 reduces lung inflammation in infants at risk of CLD, and to determine dose and dosing strategy.

Early postnatal blood concentrations of inflammation-related proteins and microcephaly two years later in infants born before the 28th post-menstrual week

BACKGROUND

To evaluate if concentrations of inflammation-related proteins were elevated in early postnatal blood specimens of preterm newborns who two years later had a small head.

METHODS

We measured 25 proteins in blood collected on days 1, 7, and 14 from 839 infants born before the 28th week of gestation and whose head circumference was measured at birth and near 24-months post-term equivalent. We excluded children whose birth head circumference was at or below the third centile. A protein concentration was considered elevated if it was in the highest quartile for gestational age and the day the specimen was obtained.

FINDINGS

When proteins were evaluated individually, elevated concentrations of SAA on day 1 and five proteins on day 14, IL-6, TNF-R2, IL-8, MCP-1, and ICAM-1 were associated with significantly increased risk of microcephaly (head circumference Z-score <-2). The ten proteins whose elevated concentrations on two separate days a week apart predicted microcephaly, but did not do so when elevated on only one of these days were CRP, SAA, IL-1β, IL-6, TNF-α, IL-8, MCP-1, ICAM-1, E-SEL, IGFBP-1. Elevated protein concentrations weakly predicted a less severe reduction in head circumference (Z-score ≥ -2, < -1).

INTERPRETATION

Concentrations of inflammation-related proteins in the circulation shortly after preterm birth provide information about the risk of a reduced head circumference more than two years later.

FUNDING

The ELGAN Study was supported by a cooperative agreement with the National Institute of Neurological Disorders and Stroke of the United States.

A meta-analysis of depression during pregnancy and the risk of preterm birth, low birth weight, and intrauterine growth restriction

CONTEXT

Maternal depressive symptoms during pregnancy have been reported in some, but not all, studies to be associated with an increased risk of preterm birth (PTB), low birth weight (LBW), and intrauterine growth restriction (IUGR).

OBJECTIVE

To estimate the risk of PTB, LBW, and IUGR associated with antenatal depression.

DATA SOURCES AND STUDY SELECTION

We searched for English-language and non-English-language articles via the MEDLINE, PsycINFO, CINAHL, Social Work Abstracts, Social Services Abstracts, and Dissertation Abstracts International databases (January 1980 through December 2009). We aimed to include prospective studies reporting data on antenatal depression and at least 1 adverse birth outcome: PTB (<37 weeks' gestation), LBW (<2500 g), or IUGR (<10th percentile for gestational age). Of 862 reviewed studies, 29 US-published and non-US-published studies met the selection criteria.

DATA EXTRACTION

Information was extracted on study characteristics, antenatal depression measurement, and other biopsychosocial risk factors and was reviewed twice to minimize error.

DATA SYNTHESIS

Pooled relative risks (RRs) for the effect of antenatal depression on each birth outcome were calculated using random-effects methods. In studies of PTB, LBW, and IUGR that used a categorical depression measure, pooled effect sizes were significantly larger (pooled RR [95% confidence interval] = 1.39 [1.19-1.61], 1.49 [1.25-1.77], and 1.45 [1.05-2.02], respectively) compared with studies that used a continuous depression measure (1.03 [1.00-1.06], 1.04 [0.99-1.09], and 1.02 [1.00-1.04], respectively). The estimates of risk for categorically defined antenatal depression and PTB and LBW remained significant when the trim-and-fill procedure was used to correct for publication bias. The risk of LBW associated with antenatal depression was significantly larger in developing countries (RR = 2.05; 95% confidence interval, 1.43-2.93) compared with the United States (RR = 1.10; 95% confidence interval, 1.01-1.21) or European social democracies (RR = 1.16; 95% confidence interval, 0.92-1.47). Categorically defined antenatal depression tended to be associated with an increased risk of PTB among women of lower socioeconomic status in the United States.

CONCLUSIONS

Women with depression during pregnancy are at increased risk for PTB and LBW, although the magnitude of the effect varies as a function of depression measurement, country location, and US socioeconomic status. An important implication of these findings is that antenatal depression should be identified through universal screening and treated.

Motor trajectories from 4 to 18 months corrected age in infants born at less than 30 weeks of gestation

BACKGROUND

Preterm infants are recognised as developing at a significantly slower rate than their full-term peers and with different movement quality.

AIM

This study aimed to describe the longitudinal gross motor trajectories of these infants in the first 18 months of (corrected) age and investigate factors associated with gross motor development.

STUDY DESIGN

A longitudinal study was conducted with convenience samples of 58 preterm infants born < or = 29 weeks of gestation and 52 control full-term infants in Australia.

OUTCOME MEASURES

The infants were assessed at 4, 8, 12 and 18 months of (corrected) age using the Alberta Infant Motor Scale (AIMS).

RESULTS

Forty-six preterm and 48 control infants completed all four assessments. The preterm group scored significantly lower on various sub-scores at all age levels. Almost half of the preterm infants demonstrated less progression in the sit sub-scale from 4 to 8 months (corrected) age, possibly due to an imbalance between flexor and extensor strength in the trunk. At 12 and 18 months of (corrected) age, lack of rotation and fluency in their movements were evident in some preterm infants. Presence of intra-ventricular haemorrhage and chronic lung disease were associated with poor motor performance at 4 months and use of postnatal steroids was associated with poor motor performance at 4, 8 and 18 months of corrected age.

CONCLUSION

The imbalance between flexor and extensor muscle strength in preterm infants had a stronger impact on motor development than usually expected. The AIMS appears to be a sensitive assessment tool to demonstrate the unique movement characteristics in this preterm cohort.

Two-year neurodevelopmental outcomes of ventilated preterm infants treated with inhaled nitric oxide

OBJECTIVE

In a randomized multi-center trial, we demonstrated that inhaled nitric oxide begun between 7 and 21 days and given for 24 days significantly increased survival without bronchopulmonary dysplasia (BPD) in ventilated premature infants weighing <1250 g. Because some preventative BPD treatments are associated with neurodevelopmental impairment, we designed a follow-up study to assess the safety of nitric oxide.

STUDY DESIGN

Our hypothesis was that inhaled nitric oxide would not increase neurodevelopmental impairment compared with placebo. We prospectively evaluated neurodevelopmental and growth outcomes at 24 months postmenstrual age in 477 of 535 surviving infants (89%) enrolled in the trial.

RESULTS

In the treated group, 109 of 243 children (45%) had neurodevelopmental impairment (moderate or severe cerebral palsy, bilateral blindness, bilateral hearing loss, or score <70 on the Bayley Scales II), compared with 114 of 234 (49%) in the placebo group (relative risk, 0.92; 95% CI, 0.75-1.12; P = .39). No differences on any subcomponent of neurodevelopmental impairment or growth variables were found between inhaled nitric oxide or placebo.

CONCLUSIONS

Inhaled nitric oxide improved survival free of BPD, with no adverse neurodevelopmental effects at 2 years of age.

The importance of intra-amniotic inflammation in the subsequent development of atypical chronic lung disease

OBJECTIVE

To examine whether the intra-amniotic inflammation is a risk factor for the development of atypical chronic lung disease (CLD).

STUDY DESIGN

A retrospective cohort study was undertaken in 72 patients who delivered preterm neonates (gestational age: 24-32 weeks) within 5 days of amniocentesis and whose neonates subsequently developed CLD. Atypical CLD was defined as CLD without respiratory distress syndrome (RDS). Intra-amniotic inflammation was defined as an elevated amniotic fluid (AF) concentration of matrix metalloproteinase-8 (MMP-8) (>23 ng/ml).

RESULTS

(1) Atypical CLD was identified in 54.2% (39/72) of cases with CLD; (2) there were no significant differences in the median gestational age at birth and the rate of antenatal corticosteroid use between infants with atypical CLD and CLD with RDS; (3) preterm newborns with atypical CLD had a significantly higher median AF MMP-8 concentration (median 373.1 ng/ml vs. 8.6 ng/ml, p = 0.003) and median AF white blood cell count (median 450.0/mm(3)vs. 5.5/mm(3), p = 0.009), and a higher rate of intra-amniotic inflammation (74.4%vs. 45.5%, p = 0.012) than those with CLD with RDS.

CONCLUSION

Intra-amniotic inflammation confers a greater risk for atypical CLD than for typical CLD with initial RDS. This novel observation strengthens the importance of prenatal inflammation as a mechanism of lung injury.

Intra-amniotic surfactant for women at risk of preterm birth for preventing respiratory distress in newborns

BACKGROUND

Early surfactant reduces mortality and pulmonary complications in preterm infants with respiratory distress syndrome. However, current surfactant administration strategies require endotracheal intubation with or without continued mechanical ventilation. Bronchopulmonary dysplasia and chronic lung disease (CLD) are associated with mechanical ventilation and potentially life-long effects. Non-invasive methods of surfactant administration including intra-amniotic surfactant may avoid endotracheal intubation and mechanical ventilation, potentially preventing development of CLD.

OBJECTIVES

To determine if intra-amniotic instillation of surfactant for women at risk of preterm birth, compared to placebo or no treatment or post-delivery tracheal surfactant instillation, reduces morbidity or mortality, or both, in preterm infants. If intra-amniotic instillation is effective, in subgroup analysis to determine the effect of 1) gestational age; 2) type of surfactant; 3) dose; 4) timing; 5) indication; and 6) multiple pregnancy.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (August 2009), MEDLINE (1950-August 2009), handsearched the Proceedings of Pediatric Academic Societies (American Pediatric Society, Society for Pediatric Research and European Society for Pediatric Research) from 1990-2009 in Pediatric Research Journal and Abstracts online and the Proceedings of Perinatal Society of Australia and New Zealand (PSANZ) (1996-2009). We also searched the Science Citation Index (Web of Science) (August 2009) and checked reference lists of identified studies. We contacted Abbott Laboratories, Inc for unpublished studies.

SELECTION CRITERIA

Published, unpublished and ongoing randomised controlled, cluster-randomised or quasi-randomised trials of intra-amniotic instillation of surfactant for women at risk of preterm birth, compared to placebo or no treatment or post-delivery tracheal surfactant instillation.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed study eligibility and quality.

MAIN RESULTS

We found no trials were found met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

We identified no randomised trials that evaluated the effect of intra-amniotic instillation of surfactant for women at risk of preterm birth. Evidence from animal and observational human studies suggest that intra-amniotic surfactant administration is potentially safe, feasible and effective. Well designed trials of intra-amniotic instillation of surfactant for women at risk of preterm birth are needed.

Academic, social, and behavioral outcomes at age 12 of infants born preterm

The effects of gradient levels of perinatal morbidity on school outcomes have been investigated at age 12 in four preterm groups, classified as healthy (no medical or neurological illness), medical morbidity, neurological morbidity, and small-for-gestational-age (SGA), and a full-term comparison group. Teachers report on academic competence, social skills, and problem behaviors. Data on school type, classroom setting, and school service use are gathered from school records. Preterm groups are found to be equivalent to full-term peers in social skills and problem behavior. Preterm groups with neurological and SGA morbidity have the lowest academic competence scores. Unexpectedly, preterm infants with medical morbidity have higher academic competence scores compared with the other preterm groups. School service use increases with greater perinatal morbidity and is contingent on multiple rather than single indicators of perinatal morbidity. Continued monitoring of preterm infants through early adolescence will ensure that appropriate school services and resources are available to maximize their school success.

Epidemiology of bronchopulmonary dysplasia

First described more than 40 years ago, bronchopulmonary dysplasia (BPD) remains one of the most serious and vexing challenges in the care of very preterm infants. Affecting approximately one-quarter of infants born <1500g birth weight, BPD is associated with prolonged neonatal intensive care unit hospitalization, greater risk of neonatal and post-neonatal mortality and a host of associated medical and neurodevelopmental sequelae. This seminar focuses on the epidemiology and definition of BPD as well as the current evidence pertaining to a number of potential preventive treatments for BPD: non-invasive respiratory support technologies, inhaled nitric oxide, vitamin A, and caffeine.

Prediction of neurodevelopmental outcome after preterm birth

Prediction of outcome after preterm birth is critical, but remains difficult, particularly in the early postnatal period. The ability to predict outcome improves parental counseling and selection of infants for early therapeutic strategies aiming at preventing or ameliorating cerebral injury. This review gives an overview of the spectrum and severity of neurodevelopmental, behavioral, and psychosocial outcomes, with discussion of predictors of outcome and, in particular, the clinical, electrophysiological, and imaging predictors. A detailed neurologic examination of infants is a valuable predictive tool in terms of later moderate to severe neurodevelopmental impairments; however, it may be limited in the immediate newborn period. Electrophysiological, neuroimaging, and clinical risk factors for adverse neurodevelopmental outcome have been identified. Good prediction is usually achieved for major functional disabilities in early childhood, but is poorer for moderate or mild long-term outcome. Future research should focus on the long-term quality of life, academic achievement, and the influence of the sociocultural environment. More emphasis should be placed on genetic diversity as a modifying factor for the large variability in outcome.

Developmental patterns from 1 to 4 years of extremely preterm infants who required home oxygen therapy

BACKGROUND

Bronchopulmonary dysplasia (BPD) remains a common complication of prematurity, with those being discharged on home oxygen at particularly high risk of adverse developmental outcomes.

AIMS

To compare the developmental patterns, from 1 to 4 years, of extremely preterm infants with BPD discharged from hospital on home oxygen, extremely preterm infants with BPD discharged breathing room air, and extremely preterm infants without BPD.

SUBJECTS

Two hundred and seventy-six infants with a gestational age of <28 weeks or birthweight <1000 g, free from sensory and motor disabilities who were followed up longitudinally to 4 years corrected age.

OUTCOME MEASURES

Children were assessed on the Griffiths Mental Development Scales at 1 and 2 years corrected age, and the McCarthy Scales of Children's Abilities at 4 years corrected age.

RESULTS

The developmental trajectories of the three groups did not differ significantly, however at 1 year corrected age the non-BPD group had significantly higher developmental scores than both BPD groups. At 2 years corrected age the non-BPD group had significantly higher developmental scores than the BPD-home oxygen group, and at 4 years corrected age no differences between the groups were evident.

CONCLUSIONS

Extremely preterm children with BPD exhibited an initial developmental lag compared to preterm peers. Children with BPD discharged breathing room air had developmental scores at 2 years corrected age that were comparable to the non-BPD group, but those discharged on home oxygen still had lower developmental scores. At 4 years, no differences between the groups were evident.

Eye-hand co-ordination skills in very preterm infants <29 weeks gestation at 3 years: Effects of preterm birth and retinopathy of prematurity

INTRODUCTION

Preterm infants are known to have low gross motor and fine motor skills. We questioned whether poor eye-hand coordination skills are associated with moderate to severe stages of Retinopathy of Prematurity (ROP).

AIMS

The aim of this study was to examine development, with specific reference to eye-hand coordination skills, among preterm infants <29 weeks gestation with different stages of ROP at 3 years of age.

METHODS AND MATERIALS

Fifteen preterm infants (<29 weeks gestation) who developed Stage 3 ROP were matched for gestation, birthweight and gender with infants who developed Stage 2 and Stage 1/no ROP. Developmental (Griffiths Mental Development Scales and Peabody Developmental Motor Scales) and ophthalmic assessments in the 3 matched groups of 15 were performed at 3 years of age.

RESULTS

1) Whilst the eye-hand coordination scores and Peabody fine motor scores were lower in the Stage 3 ROP group, they were not significantly lower than the other ROP groups. 2) Locomotor, Peabody gross motor skills and hearing and speech were significantly lower in the infants with Stage 3 ROP. The other developmental domains were not significantly different to the severe ROP group. 3) All 3 groups (of preterm infants) had lower eye-hand coordination and Peabody fine motor scores compared to test norms. 4) There were 8 of 15 infants with Stage 3 ROP who developed moderate visual problems by 3 years of age.

CONCLUSION

In preterm infants, low eye-hand coordination/fine motor scores are likely to be due to their extreme prematurity.

Abnormal deep grey matter development following preterm birth detected using deformation-based morphometry

Preterm birth is a leading risk factor for neurodevelopmental and cognitive impairment in childhood and adolescence. The most common known cerebral abnormality among preterm infants at term equivalent age is a diffuse white matter abnormality seen on magnetic resonance (MR) images. It occurs with a similar prevalence to subsequent impairment, but its effect on developing neural systems is unknown. MR images were obtained at term equivalent age from 62 infants born at 24-33 completed weeks gestation and 12 term born controls. Tissue damage was quantified using diffusion-weighted imaging, and deformation-based morphometry was used to make a non-subjective survey of the whole brain to identify significant cerebral morphological alterations associated with preterm birth and with diffuse white matter injury. Preterm infants at term equivalent age had reduced thalamic and lentiform volumes without evidence of acute injury in these regions (t = 5.81, P < 0.05), and these alterations were more marked with increasing prematurity (t = 7.13, P < 0.05 for infants born at less than 28 weeks) and in infants with diffuse white matter injury (t = 6.43, P < 0.05). The identification of deep grey matter growth failure in association with diffuse white matter injury suggests that white matter injury is not an isolated phenomenon, but rather, it is associated with the maldevelopment of remote structures. This could be mediated by a disturbance to corticothalamic connectivity during a critical period in cerebral development. Deformation-based morphometry is a powerful tool for modelling the developing brain in health and disease, and can be used to test putative aetiological factors for injury.

Neonatal antecedents for cerebral palsy in extremely preterm babies and interaction with maternal factors

BACKGROUND

Preterm delivery is associated with an increased risk of cerebral palsy (CP). The greatest risk is for infants born <28 weeks' gestation.

AIMS

To identify significant neonatal risk factors for CP and explore the interactions between antenatal and neonatal risk factors, among extremely preterm infants of 27 weeks' gestation or less.

STUDY DESIGN

Nested case control design.

METHODS

Infants born between 1989 and 1996, at 24-27 weeks' gestation, were evaluated: 30 with CP at 2 years corrected age and 120 control infants matched for gestation age. Neonatal variables were compared using matched analyses with the interaction between antenatal and neonatal factors being examined using logistic regression analyses.

RESULTS

Risk factors for CP on matched analyses included patent ductus arteriosus requiring surgical ligation, peri-intraventricular haemorrhage, moderate to severe ventricular dilatation, periventricular leukomalacia (PVL) and need for home oxygen. Independent neonatal predictors were ventricular dilatation (OR 7.3; 95% CI 1.6, 32.3), PVL (OR 29.8; 95% CI 5.6, 159.1) and home oxygen use (OR 3.4; 95% CI 1.2, 9.4). No interaction terms in the logistic models were significant between the previously identified pregnancy risk factors of absence of antenatal steroids and intrauterine growth restriction and the neonatal risk factors.

CONCLUSIONS

PVL is the most powerful independent predictor of CP in extremely preterm infants of 27 weeks' gestation or less and appears to be uninfluenced by antenatal factors.

Bronchopulmonary dysplasia in preterm infants: pathophysiology and management strategies

Bronchopulmonary dysplasia (BPD) has classically been described as including inflammation, architectural disruption, fibrosis, and disordered/delayed development of the infant lung. As infants born at progressively earlier gestations have begun to survive the neonatal period, a 'new' BPD, consisting primarily of disordered/delayed development, has emerged. BPD causes not only significant complications in the newborn period, but is associated with continuing mortality, cardiopulmonary dysfunction, re-hospitalization, growth failure, and poor neurodevelopmental outcome after hospital discharge. Four major risk factors for BPD include premature birth, respiratory failure, oxygen supplementation, and mechanical ventilation, although it is unclear whether any of these factors is absolutely necessary for development of the condition. Genetic susceptibility, infection, and patent ductus arteriosus have also been implicated in the pathogenesis of the disease. The strategies with the strongest evidence for effectiveness in preventing or lessening the severity of BPD include prevention of prematurity and closure of a clinically significant patent ductus arteriosus. Some evidence of effectiveness also exists for single-course therapy with antenatal glucocorticoids in women at risk for delivering premature infants, surfactant replacement therapy in intubated infants with respiratory distress syndrome, retinol (vitamin A) therapy, and modes of respiratory support designed to minimize 'volutrauma' and oxygen toxicity. The most effective treatments for ameliorating symptoms or preventing exacerbation in established BPD include oxygen therapy, inhaled glucocorticoid therapy, and vaccination against respiratory pathogens.Many other strategies for the prevention or treatment of BPD have been proposed, but have weaker or conflicting evidence of effectiveness. In addition, many therapies have significant side effects, including the possibility of worsening the disease despite symptom improvement. For instance, supraphysiologic systemic doses of glucocorticoids lessen the incidence of BPD in infants at risk for the disease, and promote weaning of oxygen and mechanical ventilation in infants with established BPD. However, the side effects of systemic glucocorticoid therapy, most notably the recently recognized adverse effects on neurodevelopment, preclude their routine use for the prevention or treatment of BPD. Future research in BPD will most probably focus on continued incremental improvements in outcome, which are likely to be achieved through the combined effects of many therapeutic modalities.

Predicting outcome in ex-premature infants supported with extracorporeal membrane oxygenation for acute hypoxic respiratory failure

OBJECTIVE

To identify predictors of outcome in ex-premature infants supported with extracorporeal membrane oxygenation (ECMO) for acute hypoxic respiratory failure.

METHODS

Retrospective review of ex-premature infants with acquired acute hypoxic respiratory failure requiring ECMO support in the United Kingdom from 1992 to 2001. Review of follow up questionnaires completed by general practitioners and local paediatricians.

RESULTS

Sixty four ex-premature infants (5-10 each year) received ECMO support, despite increased use of advanced conventional treatments over the decade. The most common infective agent was respiratory syncytial virus (85% of cases). Median birth gestation was 29 weeks and median corrected age at the time of ECMO support was 42 weeks. Median ECMO support duration was relatively long, at 229 hours. Survival to hospital discharge and to 6 months was 80%, remaining similar throughout the period of review. At follow up, 60% had long term neurodisability and 79% had chronic pulmonary problems. Of pre-ECMO factors, baseline oxygen dependence, younger age, and inpatient status were associated with non-survival (p < or = 0.05). Of ECMO related factors, patient complications were independently associated with adverse neurodevelopmental outcome and death (p < 0.01).

CONCLUSIONS

Survival rates for ex-premature infants after ECMO support are favourable, but patients suffer a high burden of morbidity during intensive care and over the long term. At the time of ECMO referral, baseline oxygen dependence is the most important predictor of death, but no combination of the factors considered was associated with a mortality that would preclude ECMO support.

Bronchopulmonary dysplasia is not associated with ultrasound-defined cerebral white matter damage in preterm newborns

Bronchopulmonary dysplasia (BPD) and cerebral white matter damage (WMD) are neonatal disorders that occur most commonly in those who are born much before term. In a large multicenter database, we sought to determine whether the two disorders occur together more frequently than expected and whether BPD and other neonatal respiratory characteristics are more common among infants who develop ultrasound-defined WMD than among those who do not. In a sample of 904 infants who were born before the 30th week of gestation and survived until 36 wk postmenstrual age, we did not find a co-occurrence of BPD and WMD above what would be expected by chance. Confounding does not seem to account for this lack of association between WMD and BPD. In conclusion, our findings do not support the hypothesis that BPD contributes to the occurrence of sonographically defined WMD.

Randomized trial of high-frequency oscillatory ventilation versus conventional ventilation: effect on systemic blood flow in very preterm infants

OBJECTIVE

Low superior vena cava (SVC) flow is common in very preterm infants in the first day and strongly associated with periventricular hemorrhage and disability. We examined the effect of high-frequency oscillatory ventilation (HFOV) compared with conventional ventilation (CV) on SVC flow and right ventricular output.

METHODS

Forty-five infants <29 weeks were randomized before 1 hour of age to HFOV or CV. Echocardiography was performed on 43 infants at 3, 10, and 24 hours of age. Infants with low SVC flow (<50 mL/kg/min) or hypotension (mean blood pressure < or =20) were treated with volume and inotrope.

RESULTS

Infants allocated to HFOV (n=23) and to CV (n=20) were well matched. There was a nonsignificant trend toward more infants on HFOV having SVC flow <50 mL/kg/min (48% vs 20%) and receiving volume and inotropes (61% vs 40%). There were no significant differences in mean SVC flow or right ventricular output at 3, 10, or 24 hours. Infants on HFOV had a significantly higher calculated upper body vascular resistance at 10 hours and mean blood pressure at 24 hours.

CONCLUSIONS

There were no significant adverse effects of HFOV on systemic blood flow in very preterm infants during the first 24 hours of life.

Cognitive and behavioral deficits in premature graduates of intensive care

A substantial number of VLBW graduates of intensive care develop cognitive and behavioral problems, even in the absence of neuroimaging abnormalities. Although this article has highlighted the potential, important, contributing role of medical and stressful, neonatal, environmental conditions to the development of these deficits, it is not all-encompassing, and there are additional prenatal (ie, in utero stress, drug exposure) and neonatal (ie, infectious) contributing factors. The long-term, outcome data presented in this article are pertinent to the more mature, VLBW infant, and it remains unclear and critically important to delineate the long-term, neurobehavioral outcome of those extremely low birth-weight survivors born at the cutting limit of viability.

Validity of the Test of Infant Motor Performance for discriminating among infants with varying risk for poor motor outcome

OBJECTIVE

The objective was to assess the ability of the Test of Infant Motor Performance (TIMP) to discriminate among infants with varying degrees of risk for motor developmental morbidity on the basis of perinatal medical complications.

STUDY DESIGN

Ninety-eight infants were tested weekly with the TIMP until 4 months of age. Comparisons were made among 5 groups of infants: (1) term infants without significant medical problems (low risk); (2) infants born prematurely with no significant medical problems (medium risk); (3) infants born at <30 weeks' gestational age or with birth weight <1500 g (high risk); (4) infants with chronic lung disease (high risk); and (5) infants with brain insults (high risk). A random-effects growth curve analysis assessed differences between the groups in slope and level of development across time.

RESULTS

Infants in the low- and medium-risk groups did not differ from each other but were significantly better performers than infants in the high-risk groups. Infants with brain insults performed significantly less well than all other infants, both in absolute level of performance and in developmental slope across time. Performance by black infants averaged 2 points higher than that of other infants.

CONCLUSIONS

The TIMP can discriminate among infants with differing risks for motor developmental delay.