The Impact of Different Degrees of Intraventricular Hemorrhage on Mortality and Neurological Outcomes in Very Preterm Infants: A Prospective Cohort Study

We have performed brain scanning by computed tomography on 46 consecutive live-born infants whose birth weights were less than 1,500 gm; 20 of them had evidence of cerebral intraventricular hemorrhage. Nine of the 29 infants who survived had IVH. Four grades of IVH were identified. Grade I and II lesions resolved spontaneously, but there was prominence of the interhemispheric fissue on CT of the infants at six months of age. Hydrocephalus developed in infants with Grade III and IV lesions. Seven of the surviving infants with IVH did not have clinical evidence of hemorrhage. There were no significant differences between the infants with and without IVH in birth weight, gestational age, one- and five-minute Apgar scores, or the need for resuscitation at birth or for subsequent respiratory assistance.

In the absence of effective interventions to prevent preterm births, improved survival of infants who are born at the biological limits of viability has relied on advances in perinatal care over the past 50 years. Except for extremely preterm infants with suboptimal perinatal care or major antenatal events that cause severe respiratory failure at birth, most extremely preterm infants now survive, but they often develop chronic lung dysfunction termed bronchopulmonary dysplasia (BPD; also known as chronic lung disease). Despite major efforts to minimize injurious but often life-saving postnatal interventions (such as oxygen, mechanical ventilation and corticosteroids), BPD remains the most frequent complication of extreme preterm birth. BPD is now recognized as the result of an aberrant reparative response to both antenatal injury and repetitive postnatal injury to the developing lungs. Consequently, lung development is markedly impaired, which leads to persistent airway and pulmonary vascular disease that can affect adult lung function. Greater insights into the pathobiology of BPD will provide a better understanding of disease mechanisms and lung repair and regeneration, which will enable the discovery of novel therapeutic targets. In parallel, clinical and translational studies that improve the classification of disease phenotypes and enable early identification of at-risk preterm infants should improve trial design and individualized care to enhance outcomes in preterm infants.

Birth before 26 weeks of gestation is associated with a high prevalence of neurologic and developmental disabilities in the infant during the first two years of life. We studied at the time of early school age children who had been born at 25 or fewer completed weeks of gestation in the United Kingdom and Ireland in 1995. Each child had been evaluated at 30 months of age. The children underwent standardized cognitive and neurologic assessments at six years of age. Disability was defined as severe (indicating dependence on caregivers), moderate, or mild according to predetermined criteria. Of 308 surviving children, 241 (78 percent) were assessed at a median age of six years and four months; 160 classmates delivered at full term served as a comparison group. Although the use of test reference norms showed that cognitive impairment (defined as results more than 2 SD below the mean) was present in 21 percent of the children born extremely preterm (as compared with 1 percent in the standardized data), this value rose to 41 percent when the results were compared with those for their classmates. The rates of severe, moderate, and mild disability were 22 percent, 24 percent, and 34 percent, respectively; disabling cerebral palsy was present in 30 children (12 percent). Among children with severe disability at 30 months of age, 86 percent still had moderate-to-severe disability at 6 years of age. In contrast, other disabilities at the age of 30 months were poorly predictive of developmental problems at 6 years of age. Among extremely preterm children, cognitive and neurologic impairment is common at school age. A comparison with their classroom peers indicates a level of impairment that is greater than is recognized with the use of standardized norms. Copyright 2005 Massachusetts Medical Society.