Ventilation in Preterm Infants and Lung Function at 8 Years

Ventilation in Preterm Infants and Lung Function at 8 YearsTo the Editor: Doyle et al. (July 27 issue) 1 found no reduction in the rate of bronchopulmonary dysplasia and an increased rate of obstructive lung disease in a cohort of infants born in 2005, as compared with a cohort born in 1997.The lower survival rate that was observed and the shorter courses of mechanical ventilation in 1991 and 1992, as compared with the later cohorts (1997 and 2005), suggest that babies who were at the highest risk for bronchopulmonary dysplasia did not survive long enough for it to develop; thus, the earlier cohort (1991-1992) cannot be compared with the 2005 cohort.There was no significant difference between the 1997 cohort and the 2005 cohort in the rate of endotracheal ventilation, and it has been shown that even short exposure to endotracheal positive pressure ventilation is harmful. 2 There was a striking decrease in the rate of use of postnatal glucocorticoids between these two periods, from 46% in the 1997 cohort to 23% in the 2005 cohort.These differences among eras could explain the results found by Doyle et al.The study conducted by Doyle et al. may suggest that we should try to further minimize the use of endotracheal ventilation by using noninvasive ventilation more and perhaps that we should adopt policies of using postnatal glucocorticoids, such as inhaled glucocorticoids, 3 lowdose hydrocortisone, 4 or intratracheal glucocorticoids with surfactant, 5 that do not adversely affect the neurodevelopmental outcome.