Oct 13 2004
When babies are born prematurely, their lungs are not able to produce a protein that helps them breathe.
Now, using a device already used in the neonatal intensive care unit to monitor lung function in premature infants, University of Michigan Health System researchers have taken a step in helping neonatal specialists administer a replacement substance that helps babies breathe easier.
By comparing two available types of this substance, called surfactant, researchers found one formulation may be more effective in the long run.
“It’s more than just comparing Coke and Pepsi. The two different surfactants we looked at seem to have a different course of action,” says senior study author Steven M. Donn, M.D., director of Neonatal-Perinatal Medicine at UMHS and professor of Pediatrics and Communicable Diseases at the U-M Medical School.
“Although we didn’t see much of a change in lung function immediately after their administration, the Infasurf seemed to have a more lasting effect. Infants didn’t show a dramatic effect immediately after receiving it, but they required fewer doses than the babies treated with Survanta. Because these medications are extremely expensive, there’s a substantial cost savings when we use less,” Donn says.
The study appears in the October issue of the Journal of Perinatology.
Respiratory distress syndrome is a major complication for babies born prematurely. These infants do not produce enough surfactant, the naturally occurring substance that prevents the collapse of the air sacs within the lungs and enhances the exchange of oxygen and carbon dioxide. Administering animal-derived or synthetic forms of surfactant can help improve lung function, research has shown, and this has dramatically increased the survival of infants born extremely early.
In this study, researchers randomly assigned 40 infants born at U-M’s C.S. Mott Children’s Hospital to receive either Survanta or Infasurf, two animal-derived surfactants. Babies qualified for surfactant if they were born before 37 weeks’ gestation, tests indicated respiratory distress syndrome and they required a mechanical ventilator to help them breathe.
Both surfactants were given according to their manufacturers’ recommendations and babies were monitored using the V.I.P. Bird Gold Infant/Pediatric Ventilator and Graphic Monitor. The ventilator and the monitor, which Donn helped to develop and test at UMHS, are commonly used in neonatal ICU’s across the country to help premature newborns breathe more easily and comfortably.
“It’s a tool that is readily available. After administering the surfactant, we can monitor the results being reported on this tool to adjust the ventilator to the specific needs of each baby, individually. We’re able to tell in real time how much gas volume the baby is moving in and out. If the pressure is too much or not enough for the baby, we can immediately adjust the ventilator,” says lead study author Mohammad A. Attar, M.D., clinical instructor in the Department of Pediatrics and Communicable Diseases at U-M Medical School.
The researchers found similar changes in lung function one hour after administering each surfactant, but found that infants who received Infasurf showed a better response over a longer period. In addition, infants treated with Survanta required twice as many doses and were more likely to require more than two doses.
Survanta and Infasurf, both derived from cows, are currently available and FDA-approved, but new surfactants are on the horizon, including a synthetic version. Donn and Attar see their current study as a first step and stress the need to continuously compare efficacy and cost effectiveness of new surfactants to help doctors determine what is best for their infant patients.
In addition to Donn and Attar, study authors were Michael Becker and Ronald Dechert from the Department of Critical Care Support Services at UMHS.