Medical providers who care for the tiniest babies, the premature ones, have gone about as far as they can in knocking down age barriers to survival. Now efforts are focused on minimizing the adverse outcomes that some of those tiny patients have.
Twenty-three weeks' gestation seems to be about the youngest that babies have a real fighting chance. But technology, technique, continuing research and experience are combining to make strides in quality of life for premature infants. And that's likely to continue, said Dr. Donald Null, director of the Newborn Intensive Care Unit at Primary Children's Medical Center, which turns 25 this month.
Over the past decade, he said, neonatalogy has been able to lower the 50 percent survival age, which is now about 24 weeks, meaning half the babies born at that stage survive. "And we do have a number of babies born at 23 weeks who survive, probably 20 to 30 percent. But the smaller you are, the greater risk there is for complications."
It's not uncommon for severely premature infants to have complications, including eye, lung and neuro-developmental problems. "There are a whole host of difficulties that the very small baby gets that impacts upon either survival or long-term outcomes," he said. "And those are the areas that I think we are working hardest on now — to try to get not just survival but survival with good outcomes. I think we've made some progress with that; I'm not sure we're going to make a whole lot of difference in survival any more."
Today, a baby born at 28 weeks has a 90 percent chance of living. In the late 1960s, a baby born at 30 weeks didn't have a 50 percent chance.
One of the biggest barriers premature babies face is inadequate development of the lungs, Null said. The last decade has changed how NICUs use ventilators so that lung injury has been reduced. Ventilators now provide smaller volume with each breath. Surfactant has significantly improved outcomes. Steroids are now sometimes given to mothers before babies are born prematurely to help the lungs mature a little. And there's "good evidence that babies who don't have severe lung disease don't get as many central nervous system or eye complications."
Still, a baby's lungs are not fully developed until term. And if the alveoli or air sacs don't develop before an infant is born, they may not develop well at all. By age 4 to 6, a child has the alveoli he is going to have. That's one reason very premature babies are at such high risk. And when some of the treatment that may aid survival interrupts development of those air sacs, infections can injure the lungs. Although most preemies appear to do well, they may grow up with less pulmonary reserve. They may be more susceptible to things that can injure the lungs, like smoking, infection or pollutants.
And while most normal adults could lose a major portion of a lung and do all right in everyday activities, a pre-term infant is already much like an adult who has lost a big part of a lung. Only that's their baseline, so if something injures the lung, the chance of developing respiratory failure is much higher, said Null.
Neurological improvements have been impressive, as well. The incidence of bleeding into the brain is lower in premature babies than it once was. That bleeding increases risk of developmental delays, cerebral palsy, motor deficits and intellectual deficits like mental retardation and learning disorders.
Occupational and physical therapists use stimulation techniques to literally change futures. Parents with pre-term infants are learning the stimulation parents can provide to any child to make her brighter is even more important with premature birth. That includes reading, personal interactions and more. "People used to think you are what you are. But you can improve the overall intellectual development of babies by these various stimulation things." The period leading up to school age is most critical, although it can still have an impact even later on.
Eye disease is another area that has seen great improvement. Premature babies have a much-reduced incidence of severe retinopathy, so that most of those who do have problems are very immature — 26 weeks or less. Laser treatment has made it possible to prevent many infants from becoming blind. "There's still an impairment but very reasonable, very usable vision," Null said.
One of the main changes is the decreasing importance of size in preemies. Even heart surgery can be done on babies who weigh as little as 3.5 pounds, not the 10 pounds doctors used to desire. General surgery, if needed, can be done on babies who weigh less than 2 pounds.
Monitoring equipment, IV pumps that pump tiny amounts of fluid into tiny recipients and catheters that fit better have all made dramatic improvements in care, yet only within the past 10 years have isolettes have become "state of the art."
Health care providers also know a great deal more about pain medication and sedation for babies than they did in earlier decades. At one time it was believed that preemies didn't feel pain as much, which is not true.
"We are learning how much of a person these tiny premature infants are," said Null. "The fact is that the things you do to them can impact upon their ultimate development."
It's not without a downside, though. Some babies survive but have extremely severe damage, and that isn't easy to predict. And because technology is so good, people expect problems won't occur.
"One of the things people have to understand is the risk for the very immature baby is very high," Null said.
PCMC plans 25-year reunion
Primary Children's Medical Center is inviting all children who have ever been hospitalized in its Newborn Intensive Care Unit to attend the 25-year NICU reunion Sept. 20.
It will be held at the Jewish Community Center, 2 North Medical Drive, just north of the hospital, from 11 a.m. to 5 p.m. It's a chance to see old friends and includes activities for the entire family, including swimming, games, crafts, a climbing wall, a memory room, great food and more. It's free to the NICU graduate families. You can register by calling 801-588-3833 or sign up online at www.primarychildrens.com.