Avery says that thanks to this new therapy, the U.S. infant mortality rate has been cut by 50 percent, and RDS is no longer the leading cause of death in premature infants.

Current Treatments

Currently, two methods of treatment are in use. In surfactant replacement therapy, surfactant is administered to the infant's lungs and then stimulates the lungs to produce their own.

Surfactant production can also be stimulated by the delivery of glucocorticoid, a steroid, to pregnant women. The fetus secretes surfactant into the amniotic fluid, which can then be tested by doctors in amniocentesis to determine whether or not the newborn will have RDS.

Part of the success of surfactant therapy has been the efficiency of liquid administration, says Avery. With infusion down the trachea, 20 times the amount of the substance reaches the lungs as compared with aerosol treatment, which was previously the standard method of administration of pulmonary drugs.

This may open doors for treatment of other diseases, says the neonatologist.

"We may be able to use surfactant to distribute other drugs into the lungs," she says. Such applications could be used for adults as well as infants.

Because of its inherent low surface tension, surfactant can move easily through the lung, distributing very evenly, Avery says.

In a paper published this year, Avery and other researchers found that surfactant is an effective vehicle for delivery of drugs into the lungs of hamsters. One of the drugs tested, pentamidine, may be of use in combatting a form of pneumonia which often proves deadly to AIDS patients.

Surfactant and Diabetes

In the past, says Avery, high numbers of mothers with poorly controlled diabetes resulting in stillborn infants caused many obstetricians to utilize Caeserian sections in delivery.

What happened, however, was that many of these infants were born with immature lungs that did not produce enough surfactant. By performing autopsies on a large number of stillborn infants as well as those who died of RDS after delivery, Avery found that the lack of surfactant was due to the high blood glucose of these infants.

Because of this high level of glucose passed through the placenta by the mother, a large amount of insulin will be produced by the non-diabetic fetus.

Insulin opposes the action of enzymes necessary to make surfactant, says Avery, and thus leads to immature lung formation.

With induction of the steroid glucocorticoid into the mother and surfactant replacement therapy, many stillborns are now avoided, she says.