Bronchopulmonary dysplasia and neurodevelopmental outcome in extremely preterm neonates

Abstract

We tested the hypothesis that the use of supplemental oxygen (sO2) at discharge from the NICU in extremely preterm neonates is associated with a greater risk of neurodevelopmental impairment (NDI) at 18 months corrected gestational age (CGA) than the risk of NDI of those neonates discharged in room air. Four hundred twenty-four charts were retrospectively reviewed from infants born at <27 weeks and transferred to Nationwide Children's Hospital from December 1, 2004 to June 14, 2010. Use of sO2 was evaluated on day of life (dol) 28, at 36 weeks post-menstrual age (PMA), and at discharge. Logistic regression was used to identify postnatal risk factors associated with sO2 at discharge and NDI. At dol 28, 96 % of surviving patients received sO2, and therefore had bronchopulmonary dysplasia (BPD) by definition from a National Institutes of Child Health and Human Development workshop. At 36 weeks PMA, 89 % continued on sO2 (moderate/severe BPD), and at discharge, 74 % continued on sO2. When factors associated with NDI were examined, the need for mechanical ventilation ≥28 days (adjOR = 3.21, p = 0.01), grade III-IV intraventricular hemorrhage (IVH) (adjOR = 4.61, p < 0.01), and discharge at >43 weeks PMA (adjOR = 2.12, p = 0.04) were the strongest predictors of NDI at 18 months CGA. There was no difference in Bayley Scales of Infant Development, third edition composite scores between patients with no/mild BPD and patients with moderate/severe BPD (cognitive p = 0.60, communication p = 0.53, motor p = 0.19) or those scores between patients on and off oxygen at discharge (cognitive p = 0.58, communication p = 0.70, motor p = 0.62).

Conclusions: The need for sO2 at discharge is not associated with an increased risk of NDI in these patients. The strongest predictors of poor neurodevelopmental outcome in this population were prolonged positive pressure support, grade III-IV IVH, and discharge at >43 weeks PMA.

Fig. 1

Patients admitted between December 1, 2004 and June 14, 2010. Three hundred forty-five patients born at <27 weeks gestation were eligible for this study on day of life (dol) 28. At discharge, there remained 276 patients of which 2 % died and 15 % did not return for follow-up at the neonatal clinic. At 18 months corrected gestational age, 30 patients had cerebral palsy (CP) and 201 patients had Bayley scores available for analysis

Fig. 2

BSID-III composite scores (cognitive, communication, and motor) of neonates born at <27weeks gestation (n = 201). Boxplots represent median and interquartile range. a Boxplots comparing no/mild BPD to those neonates with moderate/severe BPD. Student’s t test for cognitive score (p = 0.60), communication score (p = 0.53), and motor score (p = 0.19). There was no significant difference (ns) between the no/mild BPD and moderate/severe BPD groups. b Boxplots comparing no supplemental oxygen (sO ₂) at discharge to those neonates receiving sO₂ at discharge. Student's t test for cognitive score (p = 0.58), communication score (p = 0.70), and motor score (p = 0.62). There was no significant difference (ns) between the no sO₂ at discharge and sO₂ at discharge groups