Delivering nitric oxide to the lungs of premature, very-low-birth-weight infants during their second week of life improves their chances of surviving without chronic lung disease, according to a national study of nearly 600 babies.
For thousands of infants born prematurely each year in the United States, the treatment may help them to breathe easier--and shorten their hospital stay.
"Chronic lung disease is the most important long-term pulmonary complication for premature infants, so these results are very encouraging," said study leader Roberta A. Ballard, M.D., a neonatologist at The Children's Hospital of Philadelphia and the University of Pennsylvania, adding that the researchers will continue to follow the infants' health outcomes up to two years of age.
The multicenter Nitric Oxide Chronic Lung Disease Study Group (NOCLD) published the study in the July 27 New England Journal of Medicine.
In addition to the clinical benefits, the researchers found no apparent adverse effects from the nitric oxide up to 44 weeks of age. "Survival for premature infants has greatly improved over the years, but long-term complications often persist in these children," said Elizabeth G. Nabel, M.D., director of the National Heart, Lung and Blood Institute of the National Institutes of Health, which funded the five-year study. She added, "Successful and early treatment of breathing problems in these babies could represent a significant advance in improving the health and quality of life of a growing number of premature babies."
An estimated 10,000 to 15,000 infants in the United States have chronic lung disease of prematurity. Ongoing medical care for these infants, such as multiple hospitalizations, prolonged respiratory treatments and follow-up for neurodevelopmental problems, accounts for a significant portion of the overall public health burden of prematurity. In a report released this month, the Institute of Medicine estimated that overall costs for the more than 500,000 babies born prematurely in the U.S. totaled $26 billion, or $51,000 per infant.
The NOCLD clinical trial included 21 neonatal intensive care units throughout the country, enrolling infants with birth weights between 500 and 1250 grams, or about one to three pounds. Their median gestational age was 26 weeks (full-term babies are born at about 40 weeks gestational age). All the infants were receiving oxygen through ventilators and were at high risk of developing chronic lung disease, also known as bronchopulmonary dysplasia, because their lungs were immature and underdeveloped. In this condition, scarring and inflammation in lung tissue make breathing difficult, and the infant often requires prolonged mechanical ventilation and hospitalization.