Correlations between oxygen and positive pressure exposure in the neonatal intensive care unit and wheezing in preterm infants without bronchopulmonary dysplasia.

BACKGROUND: Oxygen exposure has been associated with increased wheezing and respiratory morbidity after discharge in extremely preterm infants and those with bronchopulmonary dysplasia. More mature preterm infants with less severe disease are also at risk for pulmonary complications, including rehospitalization for respiratory illnesses and wheezing disorders. Our aim was to evaluate associations between respiratory support and morbidity in preterm infants without bronchopulmonary dysplasia. METHODS: A secondary analysis was performed on 300 infants born at 28-34 weeks gestation without bronchopulmonary dysplasia. Exposure included oxygen or positive pressure, (continuous positive airway pressure or mechanical ventilation). The primary outcome was recurrent wheezing. Secondary outcomes were respiratory medications, emergency room visits, and hospitalizations. RESULTS: 50% of infants who received oxygen experienced recurrent wheezing compared to 42.4% of infants who did not (OR 1.15 CI 0.72-1.85 adjusted OR 1.15 CI 0.67-1.98). 51.1% of infants who received positive pressure experienced recurrent wheezing compared to 38.1% who did not (OR 1.57 CI 0.97-2.53 adjusted OR 1.58 CI 0.90-2.77). There were no significant associations between oxygen and positive pressure exposure and any primary or secondary outcomes in the adjusted analyses. CONCLUSIONS: After adjustment for known risk factors the analyses showed no significant associations between oxygen and positive pressure with respiratory morbidity in this population. Further study of infants with mild disease is needed.

Discordance in neonatal risk factors and early childhood outcomes of very low birth weight (<1.5 kg) twins.

OBJECTIVE: To examine the rates of discordance in neonatal risk factors and neurodevelopmental outcomes within very low birth weight twin pairs and the factors associated with discordant outcomes. STUDY DESIGN: Rates of neonatal risk factors and neurodevelopmental outcomes, and discordance in outcomes were examined for 88 very low birth weight twin pairs born between 1990 and 2005 and followed through 20 months' corrected age. RESULT: Discordance rates ranged from 17 to 42% for neonatal risk factors and from 18 to 31% for neurodevelopmental outcomes. In regression analysis, affected co-twins were significantly more likely to have had an abnormal cerebral ultrasound than their unaffected co-twins in pairs discordant for cerebral palsy (odds ratio (OR): 13.00, 95% confidence interval (CI): 2.22 to 76.03)) and in pairs discordant for neurodevelopmental impairment (OR: 4.00, 95% CI: 1.13 to 14.18). Outcomes and discordance in outcomes were similar for monochorionic and dichorionic pairs. CONCLUSION: Despite shared genetics and risk factors, twins may have discordant outcomes. Information on discordant neonatal and neurodevelopmental outcomes is important for counseling families of twins.

Improved weight attainment of extremely low-gestational-age infants with bronchopulmonary dysplasia.

OBJECTIVE: To determine whether changes in neonatal practice and morbidity since 2000 have improved the growth attainment of infants with bronchopulmonary dysplasia (BPD). STUDY DESIGN: We compared the respective z-scores of the weight, length and head circumference of extremely low-gestational-age infants (aged <28 weeks) with BPD at birth, 40 weeks and 20 months corrected age (CA) during two time periods, namely period I, 1996-1999 (n=117) and period II, 2000-2003 (n=105), and examined the effects of significant changes in neonatal practice, morbidities and neurosensory outcome on 20-month growth outcomes. RESULT: During the most recent period (2000-2003), there was a significant increase in mean weight z-scores (-1.60 vs -1.22) and decrease in rates of subnormal weight (40 vs 21%), P<0.05 at 20 months CA but not in those of length or head circumference. Significant predictors of the 20-month weight z-score included time period (period I vs II), duration of ventilator dependence and 20-month neurosensory abnormality (all P<0.05). CONCLUSION: Despite an improvement in weight since 2000, poor growth attainment remains a major problem among infants with BPD.

Clinical outcomes of neonatal meningitis in very-low birth-weight infants.

We sought to describe the clinical presentation and consequences of meningitis among 64 very-low-birth-weight (VLBW <1.5 kg) infants who had 67 culture-proven episodes of meningitis over an 18-year period, 1977 through 1995. Demographic and neonatal descriptors of meningitis and later outcomes were retrospectively examined and neurodevelopmental outcomes of 39 of 45 (87%) meningitis survivors were compared to those of nonmeningitis survivors followed up to 20 months corrected age. Causes of meningitis included coagulase-negative Staphylococcus in 43% of episodes, other gram-positive bacteria in 19%, gram-negative bacteria in 17%, and Candida species in 20% of episodes. Spinal fluid abnormalities were sparse, regardless of etiologic organism. Of 38 nonbloody spinal fluid taps (<1,000 erythrocytes/mm3), 6 had >30 leukocytes/mm3, 5 protein >150 mg/dL%, and 6 glucose <30 mg/dL (1.67 mmol/L). Only 10 infants (26%) had 1 or more of these spinal fluid abnormalities. Meningitis survivors had a higher rate of major neurologic abnormality (41% vs 11%, p<0.001) and subnormal (<70) Mental Development Index (38% vs 14%, p<0.001) than nonmeningitis survivors. Impairment rates did not differ by etiologic organism. The effect of meningitis on neurologic outcome persisted even after controlling for birth weight, intraventricular hemorrhage, chronic lung disease, and social risk factors (odds ratio 2.27 [95% CI 1.02, 5.05]). We conclude that despite a sparsity of abnormal spinal fluid findings, culture-proven neonatal meningitis among VLBW infants has a detrimental effect on neurologic outcome, which persists even after controlling for other risk factors.

Constipation in very-low-birth-weight children at 10 to 14 years of age.

BACKGROUND: The authors documented that very-low-birth-weight children (less than 750-g) when compared with 750-to 1,499-g birth-weight and normal-birth-weight-matched controls have higher than normal rates of neurosensory and cognitive impairments at school age. In this population, the authors found a higher rate of constipation than expected among 19 of 59 (32%) less-than-750-g-birth-weight children. The authors therefore wanted to evaluate in greater detail the problem of constipation and associated toileting problems in this population. METHODS: Nineteen less-than-750-g-birth-weight children with constipation were matched to the next less than 750-g-birth-weight child of comparable age, sex, and race who did not have constipation. A telephone questionnaire was administered to 15 of 19 parents of the less-than-750-g-birth-weight children who had constipation. RESULTS: The 15 children with constipation had significantly higher rates of neurosensory impairment (7 [47%] vs. 1 [7%]) and lower mean WISC III IQ scores (72 +/- 22 vs. 89 +/- 13) when compared with birth-weight-matched controls without constipation (P < 0.05). The constipated children also had significantly higher rates of associated toileting problems, including encopresis (8[53%] vs. 1 [7%])and stool withholding (9 [60%] vs. 2 [13%]; P < 0.05). CONCLUSION: The higher incidence of constipation among less-than-750-g-birth-weight children is associated with neurodevelopment impairment. Awareness of this problem and preventive intervention to ensure regular stools could possibly decrease the high rate of constipation and associated toileting problems.

Long-term family outcomes for children with very low birth weights.

OBJECTIVE: To examine long-term outcomes in families of children with very low birth weights (<1500 g) in relation to the extent of low birth weight and neonatal medical risk. DESIGN: Concurrent/cohort prospective study. SETTING: Regional follow-up program. PARTICIPANTS: Families of 60 children of school age with birth weights less than 750 g, 55 with birth weights between 750 and 1499 g, and 49 normal birth weight full-term controls. MAIN OUTCOME MEASURES: Parent ratings of psychological distress, family function, and child-related stress. RESULTS: Families with children with birth weights less than 750 g experienced greater stress than did families of controls (born at full term), and families who were sociodemographically advantaged experienced greater stress than did those who were disadvantaged. Higher neonatal medical risk also predicted a more negative impact on the family, but only in advantaged families. Regression analyses suggested that adverse family outcomes were mediated by ongoing problems in child functioning. CONCLUSIONS: Families of children with birth weights less than 750 g experience more long-term adversity than families of full-term children. Family sequelae are also present for children with very low birth weight at high neonatal medical risk. Ongoing child health and behavior problems may be the major source of these sequelae, and sociodemographic status is an important consideration in identifying family adversity. Although many families appear unaffected, results support the need to monitor family outcomes and develop interventions for both the child and family.

Longitudinal outcomes of Haemophilus influenzae meningitis in school-age children.

The purpose of this study was to investigate long-term outcomes of Haemophilus influenzae Type b meningitis in a cohort of school-age survivors. Findings from an initial assessment at mean age 10 years revealed neuropsychological, achievement, and behavioral sequelae in the children with neurologic complications during the acute-phase illness (H. Taylor, C. Schatschneider, & D. Rich, 1992). Here, the cohort was reassessed 1 and 2 years after the initial evaluation to investigate age-related influences on disease sequelae. After excluding children with hearing loss, the sample was divided into 2 groups: an affected group of 39 children with acute-phase neurologic complications and an unaffected group of 73 children without these complications. Growth-curve modeling showed poorer outcomes at the final assessment and less rapid improvement at follow-up for the affected group. Later age at assessment and later age at illness were associated with larger group differences in some outcomes. Results suggest that children with diffuse early brain insults are at risk for later-emerging sequelae.

Functional limitations and special health care needs of 10- to 14-year-old children weighing less than 750 grams at birth.

OBJECTIVE: To examine the health status, functioning, and special health care needs of children 10 to 14 years old weighing <750 g at birth. METHODS: We compared outcomes of a regional cohort of 59 children born from 1982 through 1986 weighing <750 g at birth (mean: 665 g; gestational age: 26 weeks) to matched groups of 54 children weighing 750 to 1499 g at birth and 49 children born at term. Assessments of limitations in functioning, compensatory dependence and needs for services above routine, at a mean age of 11 years, were based on responses to maternal questionnaires. Rates of these outcomes were compared between groups using logistic regression analyses that controlled for gender and social risk. RESULTS: Children weighing <750 g at birth had significantly higher rates of functional limitations, greater compensatory dependence, and need for services above routine than the other 2 groups. Compared with children born at term, the odds ratio for mental or emotional delay was 4.7 (95% confidence interval [CI]: 2.0-11.0), for restrictions in activity, 5.1 (CI: 1.6-16.3) and for blindness or difficulty seeing 3.9 (CI:1.3-11.4). With the exception of 3% of children who were severely impaired, the only compensatory aid that differentiated the children weighing <750 g at birth from the children born at term was the greater need for glasses (odds ratio [OR]: 2.8 [CI: 1.3-6.3]). Increased services above routine included special education (OR: 5.0 [CI: 2.1-11.7]), counseling (OR: 4.8 [CI: 1.0-23.1]) and special arrangements in school (OR: 9.5 [C.I. 2.1-43. 6]). CONCLUSION: Parents and educators need to be informed of the potential for disability and special health care needs of children weighing <750 g at birth.

Verbal memory deficits in children with less than 750 g birth weight.

Numerous studies have documented memory deficits in very low birthweight (VLBW, < 1500 g) children, yet we know little about the nature of these memory problems. To clarify memory sequelae and examine memory deficits in relation to the degree of low birth weight, we administered the California Verbal Learning Test-Children's Version (CVLT-C) to a regional sample of 57 < 750 g birthweight children and to groups of 53 750-1499 g birthweight children and 49 term-born controls. Group comparisons revealed significant differences between the < 750 g birthweight group and term-born children on measures of list learning, delayed recall, and inaccurate recall. In addition, the percentage improvement in correct recognitions relative to long-term delayed recall was greater in the < 750 g group than in the term-born controls. Similar differences were observed between VLBW children with and without abnormal neonatal cerebral ultrasounds (high- and low-risk groups). Differences in learning rate between the VLBW and term-born groups, and between high- and low-risk VLBW children, were evident even when vocabulary skill was covaried or when children with neurosensory deficits or IQ < 80 were excluded from analysis. The findings document deficits in verbal memory in the subset of VLBW children at greatest biological risk, and suggest that acquisition processes are selectively impaired.

Middle-school-age outcomes in children with very low birthweight.

Most previous studies of children with birthweight <750 g have focused on early childhood sequelae. To evaluate later outcomes, a regional sample of 60 <750-g birthweight children was compared at middle school age (M = 11 years) to 55 children with birthweight 750-1,499 g and 49 term controls. The groups were matched on age, gender, and demographic variables at the time of an early-school-age assessment (mean age 7 years). The <750-g birthweight group fared less well at middle school age than the term group on measures of cognitive function, achievement, behavior, and academic performance. In many instances, outcomes were less favorable for the <750-g children than for the 750 to 1,499-g group. Children in the <750-g group who were free of neurosensory disorders and global cognitive impairment performed more poorly on several tests than their term counterparts. Group differences in this subsample on tests of motor skills, math, and the ability to copy and recall a complex drawing remained significant even after controlling for IQ. Disparities between the <750-g and term groups increased with age for some measures. Despite favorable outcomes for many children in the <750-g group, this population is at risk for long-term developmental problems.

Pulmonary hemorrhage: clinical course and outcomes among very low-birth-weight infants.

OBJECTIVE: To describe the clinical course, neonatal morbidity, and neurodevelopmental outcomes of very low-birth-weight (<1500 g) children who develop pulmonary hemorrhage. DESIGN: A retrospective case-control study in which 58 very low-birth-weight infants who developed pulmonary hemorrhage during 1990 through 1994, of whom 29 survived, were each matched to the next admitted infant who required mechanical ventilation for respiratory distress syndrome and was of the same sex, race, and birth weight (within 250 g). SETTING: A regional tertiary neonatal intensive care unit and follow-up clinic for high-risk infants at University Hospitals of Cleveland, Cleveland, Ohio. MAIN OUTCOME MEASURES: Survival, neonatal morbidity, and neurodevelopmental outcome at 20 months' corrected age. RESULTS: Pulmonary hemorrhage occurred in 5.7% of the total population of very low-birth-weight infants. Despite similar severity of lung disease, significantly more infants who developed pulmonary hemorrhage received surfactant therapy compared with controls (91% vs 69%, P = .005). Infants with pulmonary hemorrhage who died had a lower birth weight and gestational age compared with those who survived (766 g vs 1023 g; 25 weeks vs 28 weeks, P<.001) and more received surfactant therapy (100% vs 83%, P = .05). Survivors with pulmonary hemorrhage did not differ significantly from controls in rates of oxygen dependence at 36 weeks corrected age (52% vs 38%), grade 3 to 4 periventricular hemorrhage (28% vs 17%), or necrotizing enterocolitis (3% vs 7%), but tended to have more seizures (24% vs 3%, P = .05), periventricular leucomalacia (17% vs 0%, P = .06), and patent ductus arteriosus (79% vs 55%, P =.09). There were no significant differences in neurodevelopmental outcomes at 20 months' corrected age, (cerebral palsy, 16% vs 14%; subnormal [<70] Bayley Mental Developmental Index, 59% vs 43%; and deafness, 13% vs 10%). CONCLUSION: Although mortality is high, pulmonary hemorrhage does not significantly increase the risk of later pulmonary or neurodevelopmental disabilities among those who survive.

Breastfeeding of very low birth weight infants.

This research examines the rate of breastfeeding among mothers of very low birth weight infants (VLBW, < 1500 grams), and the correlates of breast milk pumping and transition to nursing at the breast. Eighty-two mothers and their 69 singleton and 21 twin VLBW infants admitted to the Neonatal Intensive Care Unit (January 1-June 30, 1995) of an urban tertiary care hospital. Maternal demographic, infant birth, and neonatal data were compared according to breast or bottle feeding, and a telephone interview was administered retrospectively to mothers pumping breast milk at the time of the infant's discharge home. Of 39 mothers who chose to pump breast milk, 19 were still pumping at the time of the infant's discharge home. Only 8 made a successful transition to nursing at the breast. Mothers who continued pumping tended to be white, married, and older, and their infants had fewer neonatal complications. The rates of prolonged breast milk pumping and of nursing are very low. Specific interventions and better support might improve the success rates.

School-age outcomes in children with birth weights under 750 g.

BACKGROUND: Since the mid-1980s, increasing numbers of children with birth weights under 750 g have survived to school age. METHODS: We matched a regional cohort of 68 surviving children born from 1982 through 1986 with birth weights under 750 g (mean, 670 g; gestational age, 25.7 weeks) with 65 children weighting 750 to 1499 g at birth and 61 children born at term. Growth, neurosensory status, and functioning at school age in the three groups were compared. Associations of biologic and social risk factors with major developmental outcomes were examined by means of logistic-regression analyses. RESULTS: Children with birth weights under 750 g were inferior to both comparison groups in cognitive ability, psychomotor skills, and academic achievement. They had poorer social skills and adaptive behavior and more behavioral and attention problems. The mean (+/- SD) Mental Processing Composite score for the cohort was 87 +/- 15, as compared with 93 +/- 14 for children with birth weights of 750 to 1499 g and 100 +/- 13 for children born at term (P < 0.001). The rates of mental retardation (IQ < 70) in the three groups were 21, 8, and 2 percent, respectively; the rates of cerebral palsy were 9, 6, and 0 percent; and the rates of severe visual disability were 25, 5, and 2 percent. Major cerebral ultrasonographic abnormalities were associated with mental retardation (odds ratio, 5.4; 95 percent confidence interval, 1.8 to 15.8) and cerebral palsy (odds ratio, 15.2; 95 percent confidence interval, 3.0 to 77.4). Oxygen dependence at 36 weeks was associated with mental retardation (odds ratio, 4.5; 95 percent confidence interval, 1.2 to 10.7) and severe visual disability (odds ratio, 4.3; 95 percent confidence interval, 1.3 to 14.2). Social disadvantage, though associated with several neuropsychological outcomes, was not associated with major developmental impairment. CONCLUSIONS: Children with birth weights under 750 g who survive represent a subgroup of very-low-birth-weight children who are at high risk for neurobehavioral dysfunction and poor school performance.