Improving the treatment of premature babies
Premature babies are at risk of many serious medical complications. One of the most common of these is respiratory distress syndrome (RDS). Babies with RDS struggle to breathe because their immature lungs do not produce enough surfactant, a protein that keeps small air sacs in the lungs from collapsing. March of Dimes grantees helped develop surfactant therapy, which was introduced in 1990. Since then, deaths from RDS have been reduced by two-thirds.
Although surfactant treatment was a major breakthrough, March of Dimes grantees continue to improve it. About 20 percent of babies with RDS do not respond to surfactant treatment. Natural surfactant contains four known proteins, called SP-A, SP-B, SP-C and SP-D, but surfactant treatments contain only SP-B and SP-C. Grantee Ka Yee Christina Lee, PhD, of the University of Chicago is studying the structure and function of SP-B in order to design an improved synthetic surfactant that can mimic the activity of the natural protein and be effective when the one currently available fails. Along with surfactant, many babies with RDS receive additional oxygen and mechanical breathing assistance. These treatments, though lifesaving, can contribute to lung injury and a chronic breathing problem called bronchopulmonary dysplasia (BPD). Up to 50 percent of the smallest survivors (under about 2 pounds) develop BPD. Machiko Ikegami, MD, PhD, of the University of Cincinnati, is investigating whether adding SP-D to commercial surfactant treatments will help prevent BPD. This surfactant protein appears to help the immune system fight off lung infections and may help prevent the inflammation that contributes to lung injuries.
Lifesaving oxygen treatment unfortunately contributes to retinopathy of prematurity (ROP), a leading cause of blindness in premature babies. It results from abnormal growth of blood vessels in the retina. March of Dimes grantees are seeking to find out how too much oxygen triggers this response. The retina is the delicate light-sensing tissue that lines the back of the eye and sends messages to the brain. In severe ROP, the retina may detach from the back of the eye, resulting in loss of vision. As many as 16,000 premature babies in the United States develop some degree of ROP each year. The smallest babies, those born at less than 32 weeks gestation, are at the highest risk.Laser and other treatments can sometimes help preserve vision in babies with severe ROP. Grantee Guo-Hua Fong, PhD, at the University of Connecticut Health Center in Farmington, is seeking to find out whether a specific gene becomes overly active when there are high levels of oxygen, possibly triggering the abnormal growth of blood vessels in the eye. If so, it may be possible to develop preventive treatment by inactivating this gene. The outlook for premature babies has improved greatly. However, many of these babies face serious complications and lasting disabilities. Many March of Dimes grantees seek new ways to improve the care of these tiny babies, and others strive to prevent premature delivery.