Nitric Oxide Benefits Some Preemies
Reported July 7, 2005
(Ivanhoe Newswire) — A new study shows certain premature newborns may benefit from inhaled nitric oxide.
Inhaled nitric oxide works by widening blood vessels in the lungs to allow for a more efficient flow of oxygen and elimination of carbon dioxide. It also helps send blood to the most oxygenated areas of the lung and decreases responses that make the lungs less efficient.
Led by Krisa Van Meurs, M.D., a neonatologist at Lucile Packard Children’s Hospital at Stanford University and professor of pediatrics at its School of Medicine, researchers tested the effects of inhaled nitric oxide in 420 infants born before 34 weeks. The infants, weighing between 401 grams and 1,500 grams, or about 14 ounces to 3.3 pounds, were assigned to receive either nitric oxide or a placebo. They found nitric oxide did not improve the survival rate or prevent long-term lung damage.
Researchers did see an obvious difference when they separated the infants by weight. Inhaled nitric oxide decreased the likelihood of death or long-term lung damage for infants weighing more than 1,000 grams to 50 percent vs. 69 percent for the preemies inhaling the dummy substance. However, infants weighing less had a considerably higher risk of brain hemorrhaging and were more likely to die.
The study also showed nitric oxide treatments could increase the already-significant possibility of brain hemorrhaging in premature infants.
“This study suggests that the key to the effective use of inhaled nitric oxide may lie in choosing the right patients,” said Van Meurs. “Because of its effect on bleeding, it may not be useful in certain critically ill babies.”
While researchers warn physicians to limit the use of inhaled nitric oxide to clinical trials, they are conducting a long-term follow-up assessment on how the treatment affects the neurological development of the infants.
SOURCE: The New England Journal of Medicine, 2005;353:13-22