Alterations in brain structure and neurodevelopmental outcome in preterm infants hospitalized in different neonatal intensive care unit environments.

OBJECTIVE: To evaluate associations between neonatal intensive care unit (NICU) room type (open ward and private room) and medical outcomes; neurobehavior, electrophysiology, and brain structure at hospital discharge; and developmental outcomes at 2 years of age. STUDY DESIGN: In this prospective longitudinal cohort study, we enrolled 136 preterm infants born <30 weeks gestation from an urban, 75-bed level III NICU from 2007-2010. Upon admission, each participant was assigned to a bedspace in an open ward or private room within the same hospital, based on space and staffing availability, where they remained for the duration of hospitalization. The primary outcome was developmental performance at 2 years of age (n = 86 infants returned for testing, which was 83% of survivors) measured using the Bayley Scales of Infant and Toddler Development, 3rd Edition. Secondary outcomes were: (1) medical factors throughout the hospitalization; (2) neurobehavior; and (3) cerebral injury and maturation (determined by magnetic resonance imaging and electroencephalography). RESULTS: At term equivalent age, infants in private rooms were characterized by a diminution of normal hemispheric asymmetry and a trend toward having lower amplitude integrated electroencephalography cerebral maturation scores (P = .02; ß = -0.52 [CI -0.95, -0.10]). At age 2 years, infants from private rooms had lower language scores (P = .006; ß = -8.3 [CI -14.2, -2.4]) and a trend toward lower motor scores (P = .02; ß = -6.3 [CI -11.7, -0.99]), which persisted after adjustment for potential confounders. CONCLUSION: These findings raise concerns that highlight the need for further research into the potential adverse effects of different amounts of sensory exposure in the NICU environment.

Prenatal substance exposure: neurobiologic organization at 1 month.

OBJECTIVE: To examine the autonomic nervous system and neurobehavioral response to a sustained visual attention challenge in 1-month-old infants with prenatal substance exposure. STUDY DESIGN: We measured heart rate, respiratory sinus arrhythmia, and neurobehavior during sustained visual orientation tasks included in the Neonatal Intensive Care Unit Network Neurobehavioral Scale in 1129 1-month-old infants with prenatal substance exposure. Four groups were compared: infants with prenatal cocaine and opiate exposure, infants with cocaine exposure, infants with opiate exposure, and infants with exposure to other substances (ie, alcohol, marijuana, and tobacco). RESULTS: The infants with prenatal exposure to both cocaine and opiates had the highest heart rates and lowest levels of respiratory sinus arrhythmia during a sustained visual attention challenge compared with the other 3 groups. Infants with prenatal cocaine and opiate exposure had poorer quality of movement and more hypertonicity during the Neonatal Intensive Care Unit Network Neurobehavioral Scale examination. They also had more nonoptimal reflexes and stress/abstinence signs compared with infants with prenatal exposure to cocaine only and those with prenatal exposure to alcohol, tobacco, and marijuana. CONCLUSION: Problems with arousal regulation were identified in infants with prenatal substance exposure. Autonomic dysregulation has been implicated as a mechanism by which these difficulties occur. Our results suggest that infants with prenatal exposure to both cocaine and opiates have the greatest autonomic response to the challenge of a sustained visual attention task, possibly putting these infants at risk for problems associated with physiologic and behavioral regulation, a necessary prerequisite for early learning.