Early dexamethasone therapy in preterm infants: a follow-up study

Follow up of infants following discharge from the neonatal unit: structure and process

Reviewing high risk infants after discharge to provide ongoing clinical care and to monitor later outcomes is an important role for neonatologists and paediatricians. Clinical need is the primary reason for such follow up but the process does provide additional opportunities, for example collecting information on later outcomes is vital for health care commissioning, and to determine the longer term effects of new medical treatments. Parents welcome the early identification of any problems in their infant and the opportunity for early intervention may improve outcomes in some circumstances. However, depending on the model adopted, follow up can be costly and this expenditure must be justified by considering the benefits obtained.

The Role of Growth Hormone in Neural Development

Growth hormone (GH) is integrally involved in the development of the central nervous system (CNS), as well as during its recovery from injury, two processes that share many similarities and may influence CNS functionality. This review discusses some of the most recent findings in the field and, in particular, the ontogeny, distribution, regulation and putative functions of GH and its receptor within the CNS, particularly during development. The relative roles of peripheral GH, acting in part through insulin-like growth factor-I, and of the autocrine/paracrine GH system within the brain are considered. The potential role of GH as a therapeutic agent to influence brain development and function is discussed.

Validation of the National Institutes of Health consensus definition of bronchopulmonary dysplasia

OBJECTIVE

A number of definitions of bronchopulmonary dysplasia (BPD), or chronic lung disease, have been used. A June 2000 National Institute of Child Health and Human Development/National Heart, Lung, and Blood Institute Workshop proposed a severity-based definition of BPD for infants <32 weeks' gestational age (GA). Mild BPD was defined as a need for supplemental oxygen (O2) for > or =28 days but not at 36 weeks' postmenstrual age (PMA) or discharge, moderate BPD as O2 for > or =28 days plus treatment with <30% O2 at 36 weeks' PMA, and severe BPD as O2 for > or =28 days plus > or =30% O2 and/or positive pressure at 36 weeks' PMA. The objective of this study was to determine the predictive validity of the severity-based, consensus definition of BPD.

METHODS

Data from 4866 infants (birth weight < or =1000 g, GA <32 weeks, alive at 36 weeks' PMA) who were entered into the National Institute of Child Health and Human Development Neonatal Research Network Very Low Birth weight (VLBW) Infant Registry between January 1, 1995 and December 31, 1999, were linked to data from the Network Extremely Low Birth Weight (ELBW) Follow-up Program, in which surviving ELBW infants have a neurodevelopmental and health assessment at 18 to 22 months' corrected age. Linked VLBW Registry and Follow-up data were available for 3848 (79%) infants. Selected follow-up outcomes (use of pulmonary medications, rehospitalization for pulmonary causes, receipt of respiratory syncytial virus prophylaxis, and neurodevelopmental abnormalities) were compared among infants who were identified with BPD defined as O2 for 28 days (28 days definition), as O2 at 36 weeks' PMA (36 weeks' definition), and with the consensus definition of BPD.

RESULTS

A total of 77% of the neonates met the 28-days definition, and 44% met the 36-weeks definition. Using the consensus BPD definition, 77% of the infants had BPD, similar to the cohort identified by the 28-days definition. A total of 46% of the infants met the moderate (30%) or severe (16%) consensus definition criteria, identifying a similar cohort of infants as the 36-weeks definition. Of infants who met the 28-days definition and 36-weeks definition and were seen at follow-up at 18 to 22 months' corrected age, 40% had been treated with pulmonary medications and 35% had been rehospitalized for pulmonary causes. In contrast, as the severity of BPD identified by the consensus definition worsened, the incidence of those outcomes and of selected adverse neurodevelopmental outcomes increased in the infants who were seen at follow-up.

CONCLUSION

The consensus BPD definition identifies a spectrum of risk for adverse pulmonary and neurodevelopmental outcomes in early infancy more accurately than other definitions.

Neurodevelopmental outcomes of extremely low birth weight infants <32 weeks' gestation between 1993 and 1998

OBJECTIVE

This study evaluated the impact of changes in perinatal management on neurodevelopmental impairment (NDI) at 18 to 22 months' corrected age of low gestation (22-26 weeks) and higher gestation (27-32 weeks) extremely low birth weight infants (401-1000 g birth weight) who were cared for in the National Institute of Child Health and Human Development Neonatal Research Network during 3 epochs (1993-1994, 1995-1996, and 1997-1998). It was hypothesized that outcomes would improve over the 3 epochs.

METHODS

A multicenter cohort study was conducted of the outcomes of 3785 infants with assessments at 18 to 22 months' corrected age. Regression analyses were completed to evaluate for epoch effects, gestational age effects, and time plus gestational age interaction. Regression analyses were also performed to identify the independent associations of epoch and 4 study perinatal interventions: antenatal steroids (yes, no), high-frequency ventilation (yes, no), number of days to regain birth weight as a marker of nutritional intake, and postnatal steroids for treatment of bronchopulmonary dysplasia (yes, no) with outcomes.

RESULTS

Survival improved for both the low (55%-61%) and higher (82%-86%) gestational age groups during the 3 epochs. Regression analyses indicated that the decreased risk for adverse outcome was significantly lower in epoch 2 compared with epoch 1 with decreased rates of low Bayley Mental Development Index (MDI) and neurodevelopmental impairment (NDI). Antenatal steroids were associated with decreased risk for moderate to severe cerebral palsy (CP) and low Bayley Psychomotor Development Index. High-frequency ventilation was associated with a low Bayley MDI and NDI, and postnatal steroids were associated with moderate to severe CP, any CP, low Bayley MDI, low Bayley Psychomotor Development Index, and increased NDI.

CONCLUSION

Survival of extremely low birth weight infants improved between 1993 and 1998. Although some outcomes remained unchanged, the rates of low Bayley MDI scores and NDI improved. Antenatal steroid administration was the only study intervention associated with improved outcomes.

Randomized, controlled trial of dexamethasone in neonatal chronic lung disease: 13- to 17-year follow-up study: I. Neurologic, psychological, and educational outcomes

OBJECTIVES

To study neurologic, educational, and psychological status in adolescence of neonates enrolled in a double-blind, randomized, controlled trial of dexamethasone therapy for chronic lung disease.

PARTICIPANTS

A total of 287 infants who were chronically dependent on supplementary oxygen and were 2 to 12 weeks of age were recruited from 31 centers in 6 countries to a randomized, controlled trial of dexamethasone base (0.5 mg/kg per day for 1 week); 95% of survivors were reviewed at 3 years. Survivors from the 25 British and Irish centers were retraced at 13 to 17 years of age.

OUTCOME MEASURES

Nonverbal reasoning, British Picture Vocabulary Scale, Goodman Strengths and Difficulties Questionnaire behavior scores, school national test results, teacher ability ratings, and parental and general practitioner questionnaires.

RESULTS

A total of 195 children were eligible for the follow-up study. Information was available for 150 children (77%), with 142 (73%) being assessed in home visits. No baseline differences were detected between the children included in the follow-up study and those not included. There was a slight excess of cerebral palsy in the steroid group, which was not statistically significant (relative risk: 1.58; 95% confidence interval: 0.81-3.07). Overall disability rates in both groups were high (21% moderate and 14% severe), but with no difference between the 2 groups (for severe disability, relative risk: 0.84; 95% confidence interval: 0.37-1.86).

CONCLUSIONS

Information was obtained for 150 adolescents randomized to receive dexamethasone or placebo for neonatal chronic lung disease. Rates of disabilities and educational difficulties were high, but with no significant differences between the 2 groups. Some use of open-label steroids in the placebo group plus losses to long-term follow-up monitoring reduced the power of this study to detect clinically important differences, and this study cannot rule out a real increase in cerebral palsy, as reported by others.

Randomized, controlled trial of dexamethasone in neonatal chronic lung disease: 13- to 17-year follow-up study: II. Respiratory status, growth, and blood pressure

OBJECTIVES

To study the growth, health status, and respiratory outcomes at 13 to 17 years of infants enrolled in a double-blind, randomized, controlled trial of dexamethasone for the treatment of neonatal chronic lung disease.

PARTICIPANTS

A total of 287 infants who were chronically dependent on supplementary oxygen between 2 and 12 weeks of age were recruited from 31 centers in 6 countries to a double-blind, randomized, controlled trial of dexamethasone base (0.5 mg/kg per day for 1 week) or placebo, and survivors were evaluated at 3 years. Children from the 25 British and Irish centers were traced for reassessment at 13 to 17 years of age.

OUTCOME MEASURES

Respiratory symptoms, lung-function testing, height, weight, head circumference, blood pressure, health resource usage, and school absences.

RESULTS

There was no significant difference in respiratory outcomes between the dexamethasone and placebo groups. Lung function was impaired but with no difference between the 2 groups. Growth was also impaired in both groups, with height z score of -0.7, weight z score of -0.4, and head circumference z score of -1.1. Systolic blood pressure was >95th percentile for age and height for 15% of children, but with no difference between the 2 groups. There was no difference in the numbers of hospital admissions for respiratory causes or other causes.

CONCLUSIONS

Despite a shorter duration of neonatal assisted ventilation, there is no evidence that dexamethasone use is associated with long-term improvement in lung function. Impaired growth and poor health status are long-term consequences of neonatal chronic lung disease, irrespective of exposure to neonatal dexamethasone.

The safety, pharmacokinetics, and anti-inflammatory effects of intratracheal recombinant human Clara cell protein in premature infants with respiratory distress syndrome

Clara cell 10-kD protein (CC10) is a potent anti-inflammatory protein that is normally abundant in the respiratory tract. CC10 is deficient and oxidized in premature infants with poor clinical outcome (death or the development of bronchopulmonary dysplasia). The safety, pharmacokinetics, and anti-inflammatory activity of recombinant human CC10 (rhCC10) were evaluated in a randomized, placebo-controlled, double-blinded, multicenter trial in premature infants with respiratory distress syndrome. A total of 22 infants (mean birth weight: 932 g; gestational age: 26.9 wk) received one intratracheal dose of placebo (n = 7) or 1.5 mg/kg (n = 8) or 5 mg/kg (n = 7) rhCC10 within 4 h of surfactant treatment. Pharmacokinetic analyses demonstrated that the serum half-life was 11.6 (1.5 mg/kg group) and 9.9 h (5 mg/kg group). Excess circulating CC10 was eliminated via the urine within 48 h. rhCC10-treated infants showed significant reductions in total cell count (p < 0.0002), neutrophil counts (p < 0.001), and total protein concentrations (p < 0.01) and tended to have decreased IL-6 (p < 0.07) in tracheal aspirate fluid collected over the first 3 d of life. Infants in all three groups showed comparable growth. At 36 wk postmenstrual age, five of seven infants were still hospitalized and two of seven infants were receiving oxygen in the placebo group compared with two of seven hospitalized and one of seven receiving oxygen in the 1.5-mg/kg group and four of six hospitalized and three of six receiving oxygen in the 5-mg/kg group. A single intratracheal dose of rhCC10 was well tolerated and had significant anti-inflammatory effects in the lung. Multiple doses of rhCC10 will be investigated for efficacy in reducing pulmonary inflammation and ameliorating bronchopulmonary dysplasia in future studies.

Neonatal glucocorticosteroid treatment causes systolic dysfunction and compensatory dilation in early life: studies in 4-week-old prepubertal rats

Glucocorticosteroid treatment is widely used to prevent chronic lung disease in premature infants. Recent studies in adult rats, treated with dexamethasone in the neonatal period, report negative long-term effects on the heart and severely reduced life expectancy. We treated neonatal rats with dexamethasone and studied cardiac function after 4 wk (prepubertal age) to investigate whether the late effects as previously described are preceded by detectable alterations in cardiac function at a younger age. Male rat pups (n = 12) were injected intraperitoneally with dexamethasone on d 1, 2, and 3 (0.5, 0.3, and 0.1 mug/g) of life. Control pups (n = 10) received saline. At 4 wk the animals were anesthetized, and a pressure-conductance catheter was introduced into the left ventricle to measure pressure-volume loops. Cardiac function was measured and pressure-volume relations were determined to quantify intrinsic systolic and diastolic function. Subsequently, hearts were excised for histologic examination. Compared with saline-treated animals, dexamethasone-treated rats had a reduced ventricular weight (270 +/- 40 versus 371 +/- 23 mg, p < 0.001) and reduced systolic function (end-systolic elastance: 1.24 +/- 0.43 versus 2.50 +/- 1.39 mm Hg/muL, p = 0.028). Cardiac output was maintained and end-diastolic volume was increased (84 +/- 23 versus 59 +/- 19 microL, p = 0.012) indicating a state of compensatory dilatation. Heart rate, diastolic function, and systemic vascular resistance were unchanged. Neonatal dexamethasone treatment causes cardiac alterations that can be detected in the prepubertal period and that may precede severe cardiac dysfunction later in life. If our findings are confirmed in humans, this may have consequences for a large patient population and cardiac screening at young age may be indicated to enable secondary prevention.

Structural and functional brain development after hydrocortisone treatment for neonatal chronic lung disease

OBJECTIVE

There is much concern about potential neurodevelopmental impairment after neonatal corticosteroid treatment for chronic lung disease. Dexamethasone is the corticosteroid most often used in this clinical setting, and it has been shown to impair cortical growth among preterm infants. This study evaluated long-term effects of prematurity itself and of neonatal hydrocortisone treatment on structural and functional brain development using three-dimensional MRI with advanced image-processing and neurocognitive assessments.

METHODS

Sixty children born preterm, including 25 children treated with hydrocortisone and 35 children not treated with hydrocortisone, and 21 children born at term were evaluated, at a mean age of 8 years, with quantitative MRI and neurocognitive assessments (Wechsler Intelligence Scales for Children-Revised [WISC-R]). Automatic image segmentation was used to determine the tissue volumes of cerebral gray matter, white matter, and cerebrospinal fluid. In addition, the volume of the hippocampus was determined manually. WISC-R scores were recorded as mean intelligence scores at evaluation. Neonatal hydrocortisone treatment for chronic lung disease consisted of a starting dose of 5 mg/kg per day tapered over a minimum of 3 weeks.

RESULTS

Cerebral gray matter volume was reduced among preterm children (regardless of hydrocortisone treatment), compared with children born at term (preterm: 649 +/- 4.4 mL; term: 666 +/- 7.3 mL). Birth weight was shown to correlate with gray matter volume at 8 years of age in the preterm group (r = 0.421). Cerebrospinal fluid volume was increased among children born preterm, compared with children born at term (preterm: 228 +/- 4.9 mL; term: 206 +/- 8.2 mL). Total hippocampal volume tended to be lower among children born preterm, with a more pronounced reduction of hippocampal volume among boys (preterm: 6.1 +/- 0.13 mL; term: 6.56 +/- 0.2 mL). The WISC-R score was lower for children born preterm, compared with children born at term (preterm: 99.4 +/- 12.4; term: 109.6 +/- 8.8). Children treated with neonatal hydrocortisone had very similar volumes of gray matter (preterm with hydrocortisone: 650 +/- 7.0 mL; preterm without hydrocortisone: 640 +/- 5.6 mL), white matter (preterm with hydrocortisone: 503 +/- 6.1 mL; preterm without hydrocortisone: 510 +/- 4.9 mL), and cerebrospinal fluid (preterm with hydrocortisone: 227 +/- 7.4 mL; preterm without hydrocortisone: 224 +/- 6.0 mL), compared with untreated infants. The hippocampal volumes were similar in the 2 groups (preterm with hydrocortisone: 5.92 +/- 0.15 mL; preterm without hydrocortisone: 5.81 +/- 0.12 mL). The WISC-R score assessments were within the normal range for both groups, with no difference between the groups (preterm with hydrocortisone: 100.8 +/- 13; preterm without hydrocortisone: 98.6 +/- 12.3).

CONCLUSIONS

Prematurity is associated with mild brain structural differences that persist at 8 years of age, with associated lower scores in neurocognitive assessments. The data suggest that perinatal hydrocortisone given at the described dosage has no long-term effects on either neurostructural brain development or neurocognitive outcomes.

Effects of corticosteroids in very low birth weight newborns dependent on mechanical ventilation

Corticosteroids have been used in bronchopulmonary dysplasia prevention because of their antiinflammatory effects. Among their effects is a decrease in the incidence of bronchopulmonary dysplasia. However, short- and long-term side effects have been detected in preterm newborns.

PURPOSE

To analyze the effects of corticosteroids on bronchopulmonary dysplasia, length of stay, mortality, growth, as well as the adverse effects in very low birth weight newborns between 10 and 14 days of life and dependent on mechanical ventilation.

METHODS

Cohort study. All newborns with a birth weight under 1500 g, mechanical ventilation-dependent between 10 and 14 days of life, during the period January 2000 and June 2001 were included (n = 38). They were divided into 2 groups: Group I with corticosteroids (n = 16) and Group II without corticosteroids (n = 22). Dexamethasone administration: from the 10th day of life, d1-d3, 0.3 mg/kg/d; d4-d6, 0.2 mg/kg/d; d7-d9, 0.1 mg/kg/d. Respiratory evolution, bronchopulmonary dysplasia (oxygen dependence at 28 days of life), growth pattern and the presence of adverse effects were analyzed.

RESULTS

The incidence of bronchopulmonary dysplasia was 6.5% (Group I) and 30% (Group II), P = .07. A decrease in growth was detected in Group I compared with Group II (change in weight: Group I--47 g/week, Group II--85.5 g/week, P = .06; change in head circumference: Group I--0.75 cm/week, Group II--1 cm/week, P = .05).

CONCLUSION

Use of corticosteroids in very low birth weight infants dependent on mechanical ventilation during the first 10 to 14 days of life did not affect the respiratory evolution and occurrence of bronchopulmonary dysplasia, but the velocity of growth was reduced.

Trends in severe bronchopulmonary dysplasia rates between 1994 and 2002

OBJECTIVE

To examine temporal trends in the rates of severe bronchopulmonary dysplasia (BPD) between 1994 and 2002.

STUDY DESIGN

In a retrospective cohort study, all infants with a gestational age (GA) <33 weeks in a large managed care organization were identified. Annual rates of BPD (defined as an oxygen requirement at 36 weeks corrected GA), severe BPD (defined as respiratory support at 36 weeks corrected GA), and death before 36 weeks corrected GA were examined.

RESULTS

Of the 5115 infants in the study cohort, 603 (12%) had BPD, including 246 (4.9%) who had severe BPD. There were 481 (9.5%) deaths before 36 weeks corrected GA. Although the decline in BPD in this period was not significant, the rates of severe BPD declined from 9.7% in 1994 to 3.7% in 2002. Controlling for gestational age, the odds ratio (95% CI) for annual rate of decline in severe BPD was 0.890 (0.841-0.941). Controlling for gestational age, deaths before 36 weeks corrected GA also declined, with the odds ratio (CI) for the annual decline being 0.944 (0.896-0.996).

CONCLUSIONS

In this study population, the odds of having of BPD remained constant after controlling for GA. However, the odds of having severe BPD declined on average 11% per year between 1994 and 2002.

Minor neurological dysfunction, cognitive development, and somatic development at the age of 3 to 7 years after dexamethasone treatment in very-low birth-weight infants

The objective of this study was to assess minor neurological dysfunction, cognitive development, and somatic development after dexamethasone therapy in very-low-birthweight infants. Thirty-three children after dexamethasone treatment were matched to 33 children without dexamethasone treatment. Data were assessed at the age of 3-7 years. Dexamethasone was started between the 7th and the 28th day of life over 7 days with a total dose of 2.35 mg/kg/day. Exclusion criteria were asphyxia, malformations, major surgical interventions, small for gestational age, intraventricular haemorrhage grades III and IV, periventricular leukomalacia, and severe psychomotor retardation. Each child was examined by a neuropediatrician for minor neurological dysfunctions and tested by a psychologist for cognitive development with a Kaufman Assessment Battery for Children and a Draw-a-Man Test. There were no differences in demographic data, growth, and socio-economic status between the two groups. Fine motor skills and gross motor function were significantly better in the control group (p<0.01). In the Draw-a-Man Test, the control group showed better results (p<0.001). There were no differences in development of speech, social development, and the Kaufman Assessment Battery for Children. After dexamethasone treatment, children showed a higher rate of minor neurological dysfunctions. Neurological development was affected even without neurological diagnosis. Further long-term follow-up studies will be necessary to fully evaluate the impact of dexamethasone on neurological and cognitive development.

Impact of postnatal systemic corticosteroids on mortality and cerebral palsy in preterm infants: effect modification by risk for chronic lung disease

OBJECTIVE

In preterm infants, chronic lung disease (CLD) is associated with an increased risk for cerebral palsy (CP). However, systemic postnatal corticosteroid therapy to prevent or treat CLD, although effective in improving lung function, may cause CP. The objective of this study was to determine the effect of systemic postnatal corticosteroid treatment on death and CP and to assess any modification of effect arising from risk for CLD.

METHODS

Randomized, controlled trials of postnatal corticosteroid therapy for prevention or treatment of CLD in preterm infants that reported rates of both mortality and CP were reviewed and their data were synthesized. Twenty studies with data on 1721 randomized infants met eligibility criteria. The relationship between the corticosteroid effect on the combined outcome, death or CP, and the risk for CLD in control groups was analyzed by weighted meta-regression.

RESULTS

Among all infants who were randomized, a significantly higher rate of CP after corticosteroid treatment (typical risk difference [RD]: 0.05; 95% confidence interval [CI]: 0.02, 0.08) was partly offset by a nonsignificant reduction in mortality (typical RD: -0.02; 95% CI: -0.06 to 0.02). Consequently, there was no significant effect of corticosteroid treatment on the combined rate of mortality or CP (typical RD: 0.03; 95% CI: -0.01 to 0.08). However, on meta-regression, there was a significant negative relationship between the treatment effect on death or CP and the risk for CLD in control groups. With risks for CLD below 35%, corticosteroid treatment significantly increased the chance of death or CP, whereas with risks for CLD exceeding 65%, it reduced this chance.

CONCLUSIONS

The effect of postnatal corticosteroids on the combined outcome of death or CP varies with the level of risk for CLD.

The EPICure study: associations and antecedents of neurological and developmental disability at 30 months of age following extremely preterm birth

AIMS

To describe perinatal factors associated with later morbidity among extremely preterm children at 30 months of age corrected for prematurity.

POPULATION

Of 308 surviving children born at <or=25 weeks gestation in the United Kingdom and Ireland from March to December 1995, 283 (92%) were evaluated at 30 months of age corrected for prematurity.

METHODS

Cerebral palsy, severe motor disability, and Bayley scores were used as dependent variables in sequential multiple regression analyses to identify factors associated with adverse outcomes.

RESULTS

Adverse outcomes were consistently more common in boys. Factors related to perinatal illness, ultrasound evidence of brain injury, and treatment (particularly postnatal steroids) were associated with adverse motor outcomes (cerebral palsy, disability or Bayley psychomotor development index). Increasing duration of postnatal steroid treatment was associated with poor motor outcomes. A score was developed for severe motor disability with good negative predictive value. In contrast, mental development was associated with a broader range of factors: ethnic group, maternal educational level, the use of antenatal steroids, and prolonged rupture of membranes in addition to chronic lung disease.

CONCLUSION

Male sex is a pervasive risk factor for poor outcome at extremely low gestations. Avoidable or effective treatment factors are identified, which may indicate the potential for improving outcome.

The effects of early postnatal dexamethasone therapy on pulmonary outcome in premature infants with respiratory distress syndrome: a two-year follow-up study

AIM

To evaluate the pulmonary outcome at corrected age of 2 y on preterm infants who participated in a double-blind trial of early postnatal dexamethasone therapy (< 12 h after birth) for the prevention of chronic lung disease.

METHODS

Clinical respiratory status, blood gases, acid-base balance and pulmonary function were evaluated at corrected age of 2 y in 116 preterm infants (59 infants in the control group; 57 in the dexamethasone-treated group). In the dexamethasone-treated group, dexamethasone was administered intravenously every 12 h in tapering doses: 0.25 mg/kg on days 1 through 7, 0.12 mg/kg on days 8 through 14, 0.05 mg/kg on days 15 through 21, and 0.02 mg/kg on days 21 through 28.

RESULTS

The clinical and laboratory characteristics in the perinatal period were comparable between the groups. At the time of follow-up (mean +/- SD corrected age was 25.1 +/- 4.8 mo for the control group and 24.6 +/- 5.1 mo for the dexamethasone-treated group), there was a slightly lower mean body weight and body length, and a lower psychomotor developmental index in the dexamethasone-treated group than in the control group (10.9 +/- 2.1 vs 11.5 +/- 1.9 kg, 84.4 +/- 6.1 vs 85.9 +/- 5.8 cm, and 82 +/- 24 vs 89 +/- 26, respectively); however, these differences were not statistically significant. There were no significant differences between the control and dexamethasone-treated groups in clinical respiratory status, blood gases, acid-base balance or in lung mechanics (V(T): 9.5 +/- 2.0 vs 9.4 +/- 1.9 ml/kg; V(min): 0.23 +/- 0.04 vs 0.23 +/- 0.03 l/min/kg; C(RS): 13.1 +/- 3.9 vs 12.6 +/- 3.6 ml/kPa/kg; R(RS): 1.56 +/- 0.64 vs 1.62 +/- 0.58 kPa/l/s, respectively).

CONCLUSION

There was no apparent adverse respiratory outcome associated with early postnatal dexamethasone therapy.

Evidence-based neonatal care

Randomized controlled trials were introduced into neonatal care in the 1950s when high inspired oxygen concentrations were discovered to be the cause of an epidemic of blindness in preterm babies due to retinopathy of prematurity. Systematic reviews of many randomized controlled trials were published in an important textbook in 1992, 'Effective Care of the Newborn Infant', which was the starting point for the Neonatal Module of the Cochrane Collaboration. The 171 systematic reviews of interventions in neonatology published in the Cochrane Library provide evidence for neonatal care in many areas of the speciality. Some areas, such as management of respiratory distress with surfactant and assisted ventilation, are well covered by reviews, but others, such as resuscitation at birth and management of jaundice, are much less evidence based. Most of the systematic reviews deal with neonatal care in the developed world, and there are only a few of interest to carers in the developing world.

Corticothérapie post-natale chez le prématuré : bénéfices et risques

This review examines the risk/benefit ratio of postnatal steroid treatment in preterm infants and correlates epidemiological data with special emphasis on experimental evidence concening the impact of steroid on brain development. With all regimens, steroid treatment consistently reduced the need for assisted ventilation at 28 days of postnatal age or at term. However, neither oxygen at term nor neonatal mortality has been decreased by this treatment. Conversely, respiratory benefits should be weighed against several adverse effects: hyperglycemia, hypertension, gastrointestinal bleeding or perforation, increased risk of cerebral palsy. The impact of dexamethasone on brain development and risk factors of white matter damage could be involved in the association between postnatal steroid treatment and neurological impairment in treated infants. Injectable preparations of dexamethasone contain sulphiting preservatives which could account for the alterations in neuronal maturation observed in animal models. Early use of dexamethasone should especially be avoided for postnatal steroid treatment in premature infants. Other glucocorticoids as alternatives to dexamethasone need to be evaluated in appropriate and large controlled trials with long term follow up.

Management of infants with bronchopulmonary dysplasia in North America

The in-hospital management of infants with BPD includes minimizing the duration of mechanical ventilation and avoiding the use of high inspired oxygen concentrations while maintaining adequate oxygenation. Fluid restriction, bronchodilators, and diuretic therapy can improve lung function and reduce the need for supplemental oxygen and high ventilator settings, but do not change the ultimate course of these infants. Corticosteroids also improve lung function and accelerate weaning from oxygen and mechanical ventilation, but their use during the first weeks of life is associated with worse neurological outcome. Adequate nutrition plays an important role in lung injury protection and recovery. Infants with severe BPD frequently develop pulmonary hypertension and may benefit from the use of pulmonary vasodilators. Outpatient management must be carefully planned and carried out by experienced multidisciplinary teams. Social and financial issues must be addressed with the family and caregivers. Home oxygen and mechanical ventilation therapy are used frequently after discharge and require specialized staff and equipment. Maintenance of oxygenation and proper nutritional support are critical aspects in the post-discharge management of these infants. Immunizations and RSV prevention are also important to prevent infections in these vulnerable immunocompromised patients.

Injectable dexamethasone administration enhances cortical GABAergic neuronal differentiation in a novel model of postnatal steroid therapy in mice

Injectable dexamethasone (DXM) is widely used during the postnatal period in premature infants. However, this treatment has been associated with an increased incidence of neuromotor disorders. Few studies have directly addressed the impact of DXM therapy on neuronal differentiation. We used a murine model of postnatal steroid therapy in which mouse pups aged 3 and 4 postnatal days (P) received intraperitoneal injections of 1 mg . kg(-1) . 12 h(-1) of an injectable preparation that contained DXM and sulfites (DXM), pure DXM, or sulfites. The animals were weighed before they were killed on P5, P10, or P21, and their brains were investigated by immunohistochemistry with markers for neuronal differentiation. DXM administration was associated with a 20-30% reduction in body and brain weight gains and in cortical thickness on P5 and P10. gamma-Amino-butyric acid+ (GABA+) interneuron density was significantly increased (+50%) in the cerebral cortex of the animals given injectable DXM on P5 to P21 compared with controls (p < 0.01). In parallel, the density of cortical neurons expressing two interneuron markers (calbindin 28-kD and calretinin) increased significantly. These alterations occurred with injectable DXM but not with pure DXM or sulfites alone. In contrast, none of the study treatments modified the expression of other markers for neuronal transmission or axon myelination. In the animals that were given injectable DXM, cleaved caspase 3 antibody showed increased neuronal cell death, but calbindin antibody did not. In conclusion, in a murine model of postnatal steroid therapy, injectable DXM induced a selective increase in GABAergic neurons in the cerebral cortex.

Modeling and Remodeling of the Lung in Neonatal Chronic Lung Disease

Neonatal chronic lung disease (CLD) is the major long-term pulmonary complication of preterm birth affecting about 20% of infants who need mechanical ventilation. CLD is the result of abnormal repair processes following inflammatory lung injury that lead to remodeling of the lung. Inflammation may be initiated by a variety of stimuli including mechanical ventilation, oxygen toxicity and infection. The resultant neutrophil chemotaxis and degranulation leads to the release of enzymes such as matrix metalloproteinases that can cause proteolysis of the lung extracellular matrix. Abnormal healing with remodeling leads to poorly compliant lungs with reduced capacity for gas exchange. Drugs can influence the normal process of lung modeling or remodeling. Fetal lung development can be influenced by glucocorticosteroids and inflammation. Both can cause abnormal lung modeling with fewer, larger alveoli and accelerated lung maturation, which confers benefits in terms of reduced morbidity and mortality from respiratory distress syndrome but potentially increases the risk of subsequent lung injury. Antioxidants, such as retinol (vitamin A), administered post-natally may reduce the effects of oxidative stress leading to a modest reduction in CLD but they require repeated intramuscular injections. Postnatal glucocorticosteroid therapy can modify the lung inflammatory response and reduce CLD but it can also have detrimental effects on the developing brain and lung, thereby creating a clinical dilemma for neonatologists. Proteinase inhibitors may be a rational therapy but more research is needed before they can be accepted as a treatment for preterm neonates.'Modeling' is defined as planning or forming that follows a set pattern. The term is used to describe the normal process of lung growth and development that culminates in mature branching alveolar air spaces surrounded by a network of capillaries. Normal lung modeling occurs under a variety of genetic and hormonal influences that can be altered, leading to abnormal patterns of growth. 'Remodeling' is defined as altering the structure of or re-making and, in the case of the lung, is used to describe the abnormal patterns of lung growth that occur after lung injury. Modeling and remodeling of the lungs occur to an extent throughout life but never more rapidly than during the fetal and early neonatal periods, and factors that influence this process may lead to development of neonatal CLD. Some of the factors involved in normal and abnormal lung modeling and inflammation and glucocorticosteroid-induced remodeling in the perinatal period, in the context of neonatal CLD, are reviewed with considerations of how various drugs may influence these processes.

Management of Bronchopulmonary Dysplasia in Infants

Bronchopulmonary dysplasia (BPD) is a common cause of morbidity and mortality in preterm neonates and at present its management is unclear. Over the past three decades there has been a growing use of corticosteroids in the postnatal period; first for the treatment and then, more recently, for the prevention of BPD. The first published use of corticosteroids to treat neonatal lung disease was in 1956; however, it was only in the 1980s and 1990s that their use in neonates became commonplace. Concerns about their long-term neurodevelopmental consequences arose in the late 1990s when follow-up of randomised controlled trials indicated an increased risk of cerebral palsy after postnatal dexamethasone exposure. Dexamethasone has been the most frequently used corticosteroid in neonatal units, although others, including hydrocortisone, prednisolone and methylprednisolone, have been studied, as have inhaled corticosteroids. Systematic reviews indicate that systemic corticosteroids improve respiratory function in the short term and expedite extubation in preterm neonates. However, there is a high risk of hypertension, hyperglycaemia and gastrointestinal complications in corticosteroid-treated neonates and, if administered in the first 4 days of life, an association with long-term neurodevelopmental delay. There should be emphasis on prevention of BPD by reducing the risk factors associated with its development. There is no role for use of corticosteroids in the first 4 days of life as the high risk of long-term adverse effects outweighs any likely short-term benefits. Corticosteroid use should be limited to exceptional clinical circumstances, such as a ventilator-dependent infant after the second week of life who cannot be weaned from ventilation and whose condition is worsening. If used, they should be prescribed at the lowest effective dose for the shortest possible time. Further randomised trials of low-dose corticosteroids given after the first week of life are warranted and should assess both short- and long-term outcomes.

Preterm birth: a cost benefit analysis

Advances in prenatal and perinatal treatment of preterm and VLBW infants have dramatically increased the survival rate of these infants. Some interventions decrease long term sequelae associated with preterm birth, making them more cost-effective than other treatments. This paper reviews the cost-effectiveness of therapies targeted to protect the preterm brain. Birth in a center with a NICU improves survival and decreases the rate of severe neurologic disability. Administration of antenatal steroids increases survival and decreases rates of periventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, respiratory distress syndrome, and severe disability. Administration of antenatal steroids decreases costs per additional survivor. Addition of surfactant to the treatment of PT infants has also decreased treatment costs. Administration of surfactant is beneficial for symptomatic RDS but recognizes a greater benefit when given to infants younger than 30 weeks gestation prophylactically. Treatment with prophylactic indomethacin decreases the rate of intraventricular hemorrhage and results in cost savings in survivors. Postnatal administration of dexamethasone can lead to severe disability when administered before 7 to 10 days of life. Postnatal dexamethasone does not increase survival or decrease rates of chronic lung disease.

Neonatal dexamethasone treatment affects social behaviour of rats in later life

Synthetic glucocorticoids, like dexamethasone (DEX), have been frequently administered to premature infants to prevent chronic lung disease. Major concern has arisen about the long-term neurodevelopmental sequelae of this DEX treatment. In the present study, we found that neonatal DEX treatment in rats, using a treatment protocol resembling the one used in the clinical situation, increased social play behaviour in juvenile life. Furthermore, neonatal DEX treatment increased sexual motivation and intromission behaviour in the bi-level chamber, decreased submissive behaviour during an aggressive encounter, and impaired social memory in adulthood. These changes in social behaviour are not due to a general behavioural impairment since anxiety behaviour in the elevated plus maze and exploratory activity in the open-field were not affected in DEX rats. In addition, DEX rats showed no alteration in the total duration of social interest or social activity during a social interaction test. These effects of neonatal DEX treatment on behaviour later in life likely result from neurodevelopmental actions of the hormone since we found no differences in received maternal care between DEX and SAL treated pups. Together these results indicate that neonatal treatment with DEX selectively alters aspects of the behavioural response to social challenges. Thus, neonatal DEX treatment may lead to inappropriate interactions with conspecifics later in life. These data therefore warrant investigation of lasting and potentially adverse effects of treatment of human neonates with DEX on social functioning.

Care of very premature infants: looking to the future

Advances in prenatal care have improved survival rates in extremely preterm newborns, but cerebral palsy rates have not decreased in developed countries over the past 30 years. During the next 10 years we will probably not observe a dramatic improvement in intensive care such as that observed over the last 15 years. The man goal for the coming years will be to improve the quality of neonatal and postdischarge care in order to improve the long-term outcomes of very preterm infants.

Effects of exogenous glucose on brain ischemia in ovine fetuses

We examined the effects of prolonged moderate hyperglycemia with and without an additional rapid glucose injection on ischemic brain injury in the fetus. Twenty-five ewes (117-124 d of gestation) were assigned to one of four groups: 1) glucose-infused fetuses exposed to 30 min of carotid artery occlusion followed by 48 h of reperfusion (I/R-Glu, n = 8); 2) glucose-infused plus rapid glucose injection given 100 min before 30 min of occlusion followed by 48 h of reperfusion (I/R-GluR, n = 4); 3) placebo-infused exposed to 30 min of occlusion and 48 h of reperfusion (I/R-PL, n = 8); and 4) glucose-infused sham occlusion and 48 h of sham reperfusion (control, n = 5). After baseline measurements, fetuses were infused with glucose (9-16 mg/kg/min) for 48 h before and after carotid occlusion or sham treatment. The I/R-PL group received 0.9% NaCl. Brain pathologic outcome was determined. Serial sections stained with Luxol fast blue-hematoxylin and eosin were scored for white matter, cerebral cortical, and hippocampal lesions. These areas received graded pathologic scores of 0 to 5, reflecting the amount of injury, where 0 = 0%, 1 = 1-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-95%, and 5 = 96-100% of the area damaged. Comparisons of the pathologic scores for cerebral cortex (CC), white matter (WM), and hippocampus (H) demonstrated that the I/R-GluR (CC: 4.56 +/- 0.11, WM: 4.50 +/- 0.11, H: 3.44 +/- 0.48, mean +/- SEM) had more (p < 0.05) damage than the I/R-Glu (CC: 2.46 +/- 0.47, WM: 1.97 +/- 0.37, H: 1.81 +/- 0.36) and control (CC: 1.12 +/- 0.13, WM: 0.82 +/- 0.34, H: 0.80 +/- 0.34) groups. The pathologic scores in the I/R-Glu were (p < 0.05) greater than the control, but not the I/R-PL (CC: 2.12 +/- 0.35, WM: 2.20 +/- 0.44, H: 1.59 +/- 0.41) group. We conclude that exposure to prolonged moderate hyperglycemia before ischemia and during reperfusion does not affect the extent of brain injury, but exposure to an additional acute increase in plasma glucose concentration before ischemia is extremely detrimental to the fetal brain.

Prenatal and postnatal steroid therapy and child neurodevelopment

In recent years, scientific evidence has accumulated on the potential neuro-toxic effects of perinatal steroid therapy on the incompletely developed brain; therefore, much effort has been directed toward finding the optimal regimen that may reduce lung disease without incurring significant brain injury in fetuses and preterm infants. Current recommendations of the NIH endorse a single course of prenatal steroids in cases of imminent preterm delivery. Postnatal steroid therapy should be limited, according to the American Association of Pediatrics Guide-lines, to selected clinical cases after the first week of life. These cautions aim to decrease possible harmful effects that could affect short- and long-term neuro-developmental outcome in this high-risk population.

Effect of neonatal dexamethasone exposure on growth and neurological development in the adult rat

Until recently, the synthetic glucocorticoid dexamethasone was commonly used to lessen the morbidity of chronic lung disease in premature infants. This practice diminished as dexamethasone use was linked to an increased incidence of cerebral palsy and short-term neurodevelopmental delay. Of more concern is the fact that we know little regarding dexamethasone effects on long-term neurodevelopment. To study the effects of neonatal dexamethasone exposure on long-term neurodevelopment, we have developed a rat model where newborn pups are exposed to tapering doses of dexamethasone at time points corresponding to the neurodevelopmental age when human infants are traditionally exposed to this drug in the neonatal intensive care unit. Using a within-litter design, pups were assigned to one of three groups on postnatal day 2 (P2): handled controls, saline-injected controls, and animals receiving intramuscular dexamethasone between P3 and P6. Somatic growth was decreased in dexamethasone-treated animals. Dexamethasone-treated animals demonstrated slight delays in indexes of neurodevelopment and physical maturation at P7 and P14, but not P20. In adolescence (P45), there was no difference between groups in an open field test. However, as adult dexamethasone-treated animals were less active in the open field and spent more time in closed arms of the elevated plus maze. The serum corticosterone response to crowding stress in dexamethasone-treated animals was no different from controls, but they demonstrate a delay in return of corticosterone levels to baseline. These differences in behavior and hormonal stress responsiveness suggest that neonatal dexamethasone exposure may permanently alter function of the neuroendocrine stress axis.

Decreasing incidence of chronic lung disease despite the gradual reduction of postnatal dexamethasone use in very low birth weight infants

Dexamethasone has been widely used in very low birth weight infants (VLBWI) weighing less than 1,500 g at birth for the prevention or treatment of chronic lung disease (CLD). Recently, however the use of dexamethasone is being reduced, as its association with abnormal neurodevelopmental outcome is known. On the other hand, there have been persistent concerns about the increased risk of CLD according to the reduction of postnatal dexamethasone use. Hence, we did a retrospective cohort study to delineate the change in the incidence of CLD according to the reduction of dexamethasone use in VLBWI. The medical records of 559 VLBWI admitted to neonatal intensive care unit at Samsung Medical Center between November 1994 and December 2002 were reviewed with a focus on the use of postnatal dexamethasone and the incidence of CLD. The use of postnatal dexamethasone has significantly decreased over the study period. Especially, the use of high-dose regimen has markedly decreased. The day when postnatal dexamethasone therapy was begun has also been significantly delayed. The incidence of CLD has significantly decreased over the same period. In conclusion, the incidence of CLD has not increased despite the decreased use of postnatal dexamethasone.

Use of steroids in the perinatal period

INTRODUCTION

Corticosteroids can be used prenatally to mature the fetal lungs and postnatally to treat or prevent chronic lung disease (CLD). Randomised controlled trials have been performed to evaluate the benefits and risks of perinatal corticosteroid therapy.

METHODS

Systematic reviews of randomised controlled trials of prenatal and postnatal corticosteroids in the Cochrane Library were examined to determine the cost-benefit ratios of treatment. Outcomes are given as numbers needed to treat (NNT) or numbers needed to harm (NNH) with 95% confidence intervals (CI).

RESULTS

Prenatal corticosteroids reduce the risk of RDS (NNT 11; 95% CI 9-16), surfactant use (NNT 9; 95% CI 5-62), intraventricular haemorrhage (NNT 9; 95% CI 6-19) and neonatal mortality (NNT 23; 95% CI 16-42). There are no short-term or long-term adverse effects of a single course of prenatal betamethasone. However, repeated courses of prenatal steroids could be harmful and should be avoided outside of a randomised controlled trial. Postnatal corticosteroids can be used to prevent CLD (early use) or to treat it (late use). Beneficial effects include earlier extubation (typical NNT 5; 95% CI 4-10), reduced CLD (typical NNT 10; 95% CI 8-17) and avoidance of late steroids (NNT 7; 95% CI 6-10). However, there are significant adverse short-term effects such as hyperglycaemia (typical NNH 8; 95% CI 6-10), hypertension (typical NNH 10; 95% CI 8-14). Hy- pertrophic cardiomyopathy (typical NNH 5; 95% CI 4-11), gastrointestinal bleeding (typical NNH 17; 95% CI 11-33) and growth failure (NNH 2; 95% CI 1-2). More important are long-term adverse effects of cerebral palsy (typical NNH 8; 95% CI 6-17), developmental delay (typical NNH 7; 95% CI 4-33) and abnormal neurological examination (typical NNH 4; 95% CI 2-14). These adverse effects are more pronounced with early (<96 h) treatment but probably also occur when steroids are given later in the postnatal period.

CONCLUSIONS

A single course of prenatal betamethasone has clear benefits for the fetus who is likely to be born preterm but repeated courses may be harmful. Postnatal steroids should be avoided if at all possible. They might be indicated in very low doses for ventilator-dependent infants who might otherwise die without them.

Center differences and outcomes of extremely low birth weight infants

OBJECTIVE

Previous multicenter studies have shown significant center differences in neonatal characteristics and morbidities. This study evaluated center differences in outcome at 18 to 22 months among extremely low birth weight (ELBW; 401-1000 g) infants after adjusting for demographics and antenatal interventions, and it identified neonatal interventions associated with outcome differences.

METHODS

We assessed the outcome of 2478 liveborn infants who were admitted in 1993 and 1994 to the 12 centers of the Neonatal Research Network of the National Institute of Child Health and Human Development; 1483 (60%) infants survived to 18 to 22 months, and 1151 (78%) had comprehensive evaluations. Logistic regression analyses were performed to identify center differences and the association of 4 neonatal interventions--active resuscitation, postnatal steroids, ventilator treatment for < or =27 days, and full enteral feedings < or =24 days--with adverse outcomes (cerebral palsy, low Bayley scores, and neurodevelopmental impairment [NDI]), after adjusting for demographics and antenatal interventions.

RESULTS

Using bivariate analyses, significant center differences were identified for mortality, antenatal and postnatal interventions, social and environmental variables, neonatal morbidities, and neurodevelopmental outcomes for the 12 centers. After adjustment for maternal and infant demographics and antenatal interventions, the percentage of ELBW infants who had died or had NDI at 18 to 22 months ranged from 52% to 85%. Active resuscitation and postnatal steroids were associated with increases of NDI of 11.8% and 19.3%, whereas shorter ventilation support and shorter time to achieve full enteral feeds were associated with decreases in NDI of 20.7% and 17.3%, respectively.

CONCLUSION

There are large and disturbing differences among centers in outcomes at 18 to 22 months after adjusting for demographic and antenatal interventions. Center differences in postnatal interventions associated with differences in outcome can provide hypotheses for testing in clinical trials to improve outcome.

Outcomes at school age after postnatal dexamethasone therapy for lung disease of prematurity

BACKGROUND

We studied the outcomes at school age in children who had participated in a double-blind, placebo-controlled trial of early postnatal dexamethasone therapy (initiated within 12 hours after birth) for the prevention of chronic lung disease of prematurity.

METHODS

Of the 262 children included in the initial study, 159 lived to school age. Of these children, 146 (72 in the dexamethasone group and 74 in the control group) were included in our study. All the infants had had severe respiratory distress syndrome requiring mechanical ventilation shortly after birth. In the dexamethasone group, 0.25 mg of dexamethasone per kilogram of body weight was given intravenously every 12 hours for one week, and then the dose was tapered. We evaluated the children's growth, neurologic and motor function, cognition, and school performance.

RESULTS

Children in the dexamethasone group were significantly shorter than the controls (P=0.03 for boys, P=0.01 for girls, and P=0.03 for all children) and had a significantly smaller head circumference (P=0.04). Children in the dexamethasone group had significantly poorer motor skills (P<0.001), motor coordination (P<0.001), and visual-motor integration (P=0.02). As compared with the controls, children in the dexamethasone group also had significantly lower full IQ scores (mean [+/-SD], 78.2+/-15.0 vs. 84.4+/-12.6; P=0.008), verbal IQ scores (84.1+/-13.2 vs. 88.4+/-11.8, P=0.04), and performance IQ scores (76.5+/-14.6 vs. 84.5+/-12.7, P=0.001). The frequency of clinically significant disabilities was higher among children in the dexamethasone group than among controls (28 of 72 [39 percent] vs. 16 of 74 [22 percent], P=0.04).

CONCLUSIONS

Early postnatal dexamethasone therapy should not be recommended for the routine prevention or treatment of chronic lung disease, because it leads to substantial adverse effects on neuromotor and cognitive function at school age.

Dexamethasone therapy in neonates treated with extracorporeal membrane oxygenation

OBJECTIVE

To test the hypothesis that infants who received dexamethasone would have a shorter length of time on extracorporeal membrane oxygenation (ECMO). Study design Infants placed on ECMO for respiratory failure were randomly assigned to receive either dexamethasone for 3 days or placebo. Chest radiographs were scored through the use of a validated standard scoring system to assess lung injury.

RESULTS

Thirty infants received dexamethasone and 29 received placebo. The median (25th%, 75th%) duration of time on ECMO was 143.5 (100, 313) hours in the dexamethasone group and 160 (111, 303) hours in the placebo group (not significant). Survival was 80% in the dexamethasone group and 83% in the placebo group. Radiographic lung injury scores (mean+/-SEM) were significantly improved in the dexamethasone group (10.5+/-0.6) versus placebo (12.3+/-0.5) on day 3 of ECMO (P=.013). Hypertension developed in 27 of the 30 infants receiving dexamethasone and 13 of the 29 infants in the placebo group during ECMO (P<.01).

CONCLUSIONS

Dexamethasone given during the first 3 days of ECMO results in significant improvement in lung injury scores by day 3 of ECMO but does not significantly decrease the duration of ECMO or improve survival. The preponderance of evidence would not support the use of dexamethasone in this setting.

Traitement par vincristine des hémangiomes graves du nourrisson

AIM

To evaluate the efficacy of vincristine treatment for function- and life-threatening hemangiomas.

PATIENTS AND METHOD

Nine infants, eight girls and one boy, received vincristine treatment (VCR) for endangering hemangiomas. In six cases, the hemangiomas involved head and neck in a segmental unilateral or bilateral distribution (3/6 also had laryngeal and 2/6 tracheal location causing respiratory distress, 5/6 had eyelid and orbital involvement); one infant had disseminated neonatal hemangiomatosis (skin, liver, kidney); two infants had liver hemangiomas with cardiac failure. VCR was prescribed after failure of high-dosage corticosteroid treatment in six, and of both corticosteroids and interferon alpha 2b (5 months) in one; two infants received VCR as first line treatment.

RESULTS

A dosage of 1 mg/m(2) IV injection was delivered, with weekly injections first, and then tapering, increasing the interval between injections, depending on the clinical response. The nine infants received from 5 to 25 injections (average: 16), for a length of treatment of 1.5-8 months (average: 5.5 months). In seven patients a clear clinical response was observed at the end of the first month of treatment, while a slow protracted response was noted in two. Transient mild side effects were present in four patients.

DISCUSSION

Corticosteroid treatment, although a worldwide recognized treatment of problematic hemangiomas, cannot always control the growth of alarming hemangiomas. Interferon alpha 2a and 2b have proven a 90% effectiveness: treatment for cortico-resistant, function- and life-threatening, hemangiomas.

Prediction of outcome from the chest radiograph appearance on day 7 of very prematurely born infants

Our aim was to determine whether the chest radiograph appearance at 7 days predicted chronic lung disease development (oxygen dependency at 36 weeks post-menstrual age) or death before discharge and if it was a better predictor than readily available clinical data. Two consecutive studies were performed. In both, chest radiographs taken at 7 days for clinical purposes were assessed using a scoring system for the presence of fibrosis/interstitial shadows, cystic elements and hyperinflation and data were collected regarding gestational age, birth weight, use of antenatal steroids and post-natal surfactant and requirement for ventilation at 7 days. Oxygenation indices were calculated in the first study (study A) at 120 h and in the second (study B) at 168 h. In study A, there were 59 infants with a median gestational age of 26 weeks (range 24 to 28 weeks) and in study B, 40 infants with a median gestational age of 27 weeks (range 25-31 weeks). In both studies, infants who developed chronic lung disease had a significantly higher total chest radiograph score, with a higher score for fibrosis/interstitial shadowing than the rest of the cohort. Infants who died before discharge differed significantly from the rest with regard to significantly higher scores for cysts. In both studies, the areas under the receiver operator characteristic curves with regard to prediction of chronic lung disease were higher for the total chest radiograph score compared to those for readily available clinical data.

CONCLUSION

In infants who require a chest radiograph for clinical purposes at 7 days, the chest radiograph appearance can facilitate prediction of outcome of infants born very prematurely.

Effects of Glucocorticoids on Fetal and Neonatal Lung Development

Antenatal glucocorticoids have been used for 30 years to induce maturation of preterm fetal lungs. Stimulation of the pulmonary surfactant system has been regarded as the most important effect of antenatal glucocorticoids; however, as these drugs alter the expression of a large number of genes they affect the maturation of the lung in several other ways. Antioxidant enzyme production, lung fluid absorption and alveolar development are all affected by glucocorticoids administered in the perinatal period. There is evidence that glucocorticoids induce genes associated with the synthesis of surfactant proteins, fatty acid synthase, the epithelial sodium channel and the membrane protein sodium/potassium ATPase as well as several antioxidant enzymes including catalase, glutathione peroxidase and two superoxide dismutases. Glucocorticoids also increase the expression of vascular endothelial growth factor, which may inhibit alveolarization and lead to abnormally large alveoli. The use of both antenatal and postnatal glucocorticoids has increased in the past decade. However, as concerns about possible long-term effects have arisen, the mechanisms of how glucocorticoids alter the structure and function of the lungs needs to be determined to allow the development of more specific agents in the treatment of respiratory distress syndrome.

Antenatal corticosteroids for fetal maturation in women at risk for preterm delivery

The available data unambiguously support the beneficial, short-term fetal effects of antenatal corticosteroids in women at risk for preterm delivery. There are still several incompletely addressed questions, including the use of corticosteroids in women with preterm premature rupture of membranes, the optimal corticosteroid preparation to be used, and the impact of repeated dosing. These issues are discussed in this review from the perspective of recent scientific evidence on the mechanisms responsible for positive short-term effects on survival and possible harmful long-term effects.

Adrenal suppression and extubation rate after moderately early low-dose dexamethasone therapy in very preterm infants

OBJECTIVE

A short course of moderately early dexamethasone therapy with a starting dose of 0.5 mg/kg/day improves lung compliance and shortens the duration of ventilatory support in preterm infants with respiratory distress syndrome (RDS). We conducted a double-blind, randomized study to evaluate whether a moderately early 14-day weaning course of low-dose dexamethasone affects adrenal function and facilitates weaning from the ventilator.

PATIENTS AND METHODS

Thirty-six preterm infants with a gestational age < or =32 weeks who required ventilatory support for RDS on days 7-14 were randomized to a 14-day treatment course with dexamethasone (0.2 mg/kg/day start, tapering doses) or placebo (equivalent amounts of normal saline). Prior to the first study treatment and the day after completion of the treatment course, adrenal function was assessed from serum cortisol levels drawn before and 30 min after intravenous administration of 0.1 mg Cortrosyn. Extubation rate during treatment in both groups was compared.

RESULTS

In both groups baseline serum cortisol levels decreased significantly during treatment, but stimulated cortisol levels did not change. After the 14-day treatment course, stimulated cortisol levels increased significantly from baseline levels in both groups (p<0.001), following Cortrosyn administration. More infants in the dexamethasone group were extubated within 7-14 days of study entry than in the placebo group (p<0.05). Hyperglycemia was more frequently diagnosed in the dexamethasone group and open-label dexamethasone treatment was given more frequently in the control group.

CONCLUSIONS

A moderately early 14-day weaning course of low-dose dexamethasone does not significantly suppress the adrenal function of very preterm infants with RDS, but accelerates weaning from the ventilator.

A single course of prenatal betamethasone in the rat alters postnatal brain cell proliferation but not apoptosis

The aim of this study was to determine the effects of a clinically relevant single course of prenatal betamethasone in the rat on growth parameters with particular reference to brain cell proliferation and apoptosis. We report that administration of 170 microg kg-1 betamethasone twice within 4 h to E20 pregnant rats conveys moderate somatic growth retardation. Further, using a measure of brain cell proliferation independent of blood-brain barrier (BBB) permeability, we demonstrate for the first time that betamethasone is chronically anti-proliferative to brain cells without inducing caspase-3-mediated apoptosis. More importantly we show that there is a significant and sexually divergent rebound of neural proliferation which occurs earlier in males than in females and continues until at least 21 days of postnatal life. BBB permeability to [3H]thymidine was significantly increased by steroid treatment re-iterating the fact that tracer studies not correcting for BBB permeability, such as bromodeoxyuridine (BrdU), may be questionable in this type of study. Further, prenatal steroid treatment did not alter postnatal corticosterone levels. In summary we show that prenatal betamethasone conveys significant and long-lasting side effects and that its human clinical application in preterm labour needs more careful consideration as compared to the relative ease with which it is prescribed today.

State of the Science: Achievements and Challenges Across the Spectrum of Care for Preterm Infants

The spectrum of care for preterm infants includes the perinatal and immediate neonatal periods, the initial hospitalization period including neonatal intensive care, transition to discharge, and from discharge through the first year of life. Care issues are sometimes lifelong. Advances and achievements of the past 20 years, particularly during the perinatal period and in neonatal intensive care, have resulted in significant increases in survivability of even the smallest and least mature infants. Challenges remain, particularly in establishing evidence-based standards of nursing practice in areas such as transition to oral feedings, breastfeeding in the intensive-care nursery, and developmentally based care, and in reducing short- and long-term morbidities in children born prematurely. This article illustrates achievements and challenges across the spectrum of care for preterm infants in the 1st year of life.

Longitudinal multicenter follow-up of high-risk infants: why, who, when, and what to assess

This article reviews experience with longitudinal follow-up of high-risk infants in the National Institute of Child Health and Human Development (NICHD) Neonatal Research Network. In 1993, the Network initiated a research protocol to provide longitudinal follow-up of infants with birth weight less than 1001 g and infants with higher birth weights who participated in certain Network randomized trials. Infants are assessed at 18 to 22 months corrected age (corrected for degree of prematurity) using measures of the infant's health, growth, neuromotor, and early cognitive functioning, language, behavior, and family resources. Data from these assessments have been used to investigate potentially modifiable risk factors for cerebral palsy and delayed early cognitive functioning and to evaluate the risks and benefits of interventions assessed in randomized trials. The Network's experience thus far suggests that longitudinal follow-up can provide valuable information about treatments given to fetuses and neonates.

Magnetic resonance imaging of preterm brain injury

Magnetic resonance imaging (MRI) has proved to be a valuable tool for monitoring development and pathology in the preterm brain. This imaging modality is useful for assessing numerous pathologies including periventricular leukomalacia, intraventricular haemorrhage/germinal layer haemorrhage, and periventricular haemorrhagic infarction, and can help to predict outcome in these infants. MRI has also allowed the detection of posterior fossa lesions, which are not easily seen with ultrasound. Additionally, and perhaps most relevant, quantitative MR studies have shown differences between the normal appearing preterm brain at term equivalent age and term born infants, confirming that the brain develops differently in the ex utero environment. Further studies using quantifiable MR techniques will improve our understanding of the effects of the ex utero environment, including aspects of neonatal intensive care on the developing brain.

Developmental outcome at 18 and 24 months of age in very preterm children: a cohort study from 1996 to 1997

OBJECTIVE

To determine the effect of prematurity (gestational age (GA) < 32 weeks) on developmental outcome at the corrected age of 18 and 24 months in a regionally defined, prospective cohort study.

STUDY DESIGN

The Leiden Follow-Up Project on Prematurity (LFUPP) includes all live-born infants < 32 weeks GA, born in 1996/1997 in three Dutch health regions (n=266). Mental and psychomotor developmental indices (MDI, PDI) were determined with the Bayley Scales of Infant Development I: > or = -1 S.D.: normal, -2 to -1 S.D.: moderate delay and < -2 S.D.: severe delay.

RESULTS

At 18 months 168 (71%) and at 24 months, 151 children (64%) of 235 survivors were assessed. Moderate to severely delayed mental and/or psychomotor development occurred in 40% of the children at both ages. Children lost to follow-up were of lower socioeconomic status and more frequently of non-Dutch origin. Since non-Dutch origin negatively affected the outcome at both test ages, availability of the data of these children would probably have worsened the outcome. Postnatal treatment with dexamethasone was associated with an increased risk of delayed development. Other independent predictors of delayed development were bronchopulmonary dysplasia at 18 months and ethnicity, maternal age at birth, birthweight and gender at 24 months. After adjustment for these other predictors of delayed development, the mean PDI of dexamethasone-treated infants was 16.1 points lower than of non-treated infants at 18 months (p=0.03) and 12.7 points lower at 24 months (p=0.04).

CONCLUSIONS

At 18 and 24 months corrected age, 40% of the very prematurely born children had both delayed mental and/or psychomotor development. Treatment with dexamethasone postnatally was a major risk factor for delayed (psychomotor) development.

Human SP-A 3'-UTR variants mediate differential gene expression in basal levels and in response to dexamethasone

Human surfactant protein A (SP-A) is encoded by two genes (SP-A1, SP-A2), and each is identified with several alleles. SP-A is involved in normal lung function, innate immunity, inflammatory processes, and is regulated by glucocorticoids. We investigated the role of 3'-untranslated region (UTR) of 10 SP-A variants on gene expression using transient transfection of 3'-UTR constructs in the human lung adenocarcinoma cell line NCI-H441. We found: 1) both basal mRNA and protein levels of the reporter gene of SP-A 3'-UTR constructs are significantly (P < 0.01) reduced compared with controls (vector pGL3 and surfactant protein B pGL3) and that differences exist among alleles; and 2) after dexamethasone (Dex) treatment (100 nM for 16 h), mRNA was reduced (31-51%). Seven alleles showed a significant decrease (P < 0.05) in mRNA, and three did not. Reporter activity was also decreased, from 17% (1A(1)) to 38% (1A), with six alleles showing a significant decrease. The data indicate that the 3'-UTR of SP-As play a differential role in SP-A basal expression and in response to Dex. Therefore, a careful consideration of individual use of steroid treatment may be considered.

Nutritional state and growth and functional maturation of the brain in extremely low birth weight infants

OBJECTIVE

It is well-known that an undernutritional status influences central nervous system development in the fetal and early neonatal period. On the other hand, the maturational delay of the central nervous system is reflected as dysmature pattern (DMP) in the neonatal background electroencephalograph (EEG). Therefore, we hypothesized that the postnatal nutritional status influenced electrophysiologic maturation in extremely low birth weight infants (ELBWIs).

METHODS

ELBWIs between 24 and 27 weeks of gestational age who were admitted to Ogaki Municipal Hospital NICU from April 1997 to December 2000 were considered eligible. From the condition of enteral feeding, infants were divided into 2 groups: 1). normal nutritional group (group N), where enteral feeding had been established (100 mL/kg/d) by 3 weeks after birth; 2). undernutritional group (group U), where enteral feeding had not been established by 3 weeks after birth or was discontinued because of clinical problems. Weekly average body weight and head circumference gains were evaluated as nutritional status. EEG records were performed every 2 to 4 weeks until postnatal 15 weeks of age. DMP was defined as the appearance of immature EEG patterns for postconceptional age.

RESULTS

Twenty-one infants had serial EEG recordings; 11 infants belonged to group N and 10 infants to group U. Gestational age, birth weight, and head circumference at birth were not different between the 2 groups. The body weight of group N was significantly heavier than that of group U after 5 postnatal weeks. Similarly, the head circumference of group N was larger than that of group U after 6 weeks of postnatal age. Nine infants demonstrated DMPs. One infant belonged to group N and 8 to group U. DMPs were significantly more frequently found in group U than group N (80% vs 9%). In 6 of the 9 cases, the DMPs lasted until 38 to 40 weeks of postconceptional age. Five of the 6 infants with persistent DMPs suffered from severe undernutritional conditions. The other, who belonged to group N, was treated with corticosteroid for chronic lung disease. In 3 cases, DMPs were observed transiently and their undernutritional status was not so severe.

CONCLUSIONS

Our study indicated that a postnatal undernutritional condition was associated with DMPs in ELBWIs. Undernutritional status may affect electrophysiologic maturation.

Long-lasting effects of neonatal dexamethasone treatment on spatial learning and hippocampal synaptic plasticity: involvement of the NMDA receptor complex

The effects of neonatal dexamethasone (DEX) treatment on spatial learning and hippocampal synaptic plasticity were investigated in adult rats. Spatial learning in reference and working memory versions of the Morris maze was impaired in DEX-treated rats. In hippocampal slices of DEX rats, long-term depression was facilitated and potentiation was impaired. Paired-pulse facilitation was normal, suggesting a postsynaptic defect as cause of the learning and plasticity deficits. Western blot analysis of hippocampal postsynaptic densities (PSD) revealed a reduction in NR2B subunit protein, whereas the abundance of the other major N-methyl-D-aspartate (NMDA) receptor subunits (NR1, NR2A), AMPA receptor subunits (GluR2/3), scaffolding proteins, and Ca2+/calmodulin-dependent protein kinase II (alphaCaMKII) were unaltered. This selective reduction in NR2B likely resulted from altered receptor assembly rather than subunit expression, because the abundance of NR2B in the homogenate and crude synaptosomal fractions was unaltered. In addition, the activity of alphaCaMKII, an NMDA receptor complex associated protein kinase, was increased in PSD of DEX rats. The results indicate that neonatal treatment with DEX causes alterations in composition and function of the hippocampal NMDA receptor complex that persist into adulthood. These alterations likely explain the deficits in hippocampal synaptic plasticity and spatial learning induced by neonatal DEX treatment.

Preterm outcomes research: a critical component of neonatal intensive care

While early preterm outcome studies described the lives of preterm survivors to justify the efforts required to save them, subsequent studies demonstrated their increased incidence of cerebral palsy, mental retardation, sensory impairments, minor neuromotor dysfunction, language delays, visual-perceptual disorders, learning disability and behavior problems compared to fullterm controls. Because infants born at the lower limit of viability require the most resources and have the highest incidence of neurodevelopmental disability, there is concern that resources have gone primarily to neonatal intensive care and are not available for meeting the followup, health, educational and emotional needs of these fragile infants and their families. Despite many methodological concerns, preterm outcome studies have provided insight into risk factors for and causes of CNS injury in preterm infants. Nevertheless, it remains difficult to predict neurodevelopmental outcome for individual preterm infants. Perinatal and neonatal risk factors are inadequate proxies for neurodevelopmental disability. Recent randomized controlled trials with one to five year neurodevelopmental followup have provided valuable information about perinatal and neonatal treatments. Recognizing adverse longterm neurodevelopmental effects of pharmacological doses of postnatal steroids is a sobering reminder of the need for longterm neurodevelopmental followup in all neonatal randomized controlled trials. Ongoing longterm preterm neurodevelopmental studies, analysis of changes in outcomes over time and among centers, and evaluation of the longterm safety, efficacy and effectiveness of many perinatal and neonatal management strategies and proposed neuroprotective agents are all necessary for further medical and technological advances in neonatal intensive care.