Engineer with a Medical Mission

Every hour, 50 babies in the U.S. are born prematurely. Dr. David Carlton (B.S. ChE ’79) works to ensure that those in his care have the best chance for a healthy life.

Feb 11, 2015

For a baby developing inside of a mother, the last weeks before birth are crucial.

Connections are formed among nerves to support breathing, swallowing and other functions. Skin becomes thicker and more protective. The kidneys build their filtering capacity. The brain grows at an exponential rate; as of 35 weeks, it has just two-thirds of its volume.

Suffice to say, babies born too early enter the world at a great disadvantage. And caring for prematurely born infants — defined as having arrived at 37 weeks of gestation or sooner — is an immensely delicate and complicated mission.

In Atlanta, a prominent leader of this mission is Dr. David Carlton (B.S. ChE ’79), head of Emory University’s neonatal-perinatal medicine division. Carlton not only cares for preemies and babies born with undeveloped organs and other complications; he also oversees a cooperative of neonatal intensive care involving Emory, Grady Hospital and Children’s Healthcare of Atlanta.

Carlton took time out of a hectic schedule to talk about his path from majoring in chemical engineering at Georgia Tech to overseeing one of the nation’s most sophisticated collections of neonatal intensive care units. 

Dr. David Carlton (B.S. ChE ’79)

Every day, you see so many babies who were born much too early.

That’s right. We have about 100 in our care at any given time, including some who were born full-term but have serious complications.

What would surprise people most about these infants?

More than people think, babies in the ICU do well. They have a resilience about them that’s a little counterintuitive when you see how small they are. They might weigh only two pounds, but the vast majority will survive. I’m pleasantly surprised by their inborn nature and their willingness to fight. Doctors and nurses who take care of these babies delight in it.

Has the story of one of these babies stayed with you over time?

When I was [on the faculty at] the University of Utah, one baby was born very, very young. Her parents had little hope for her — she weighed little more than a pound. We didn’t think she would survive.

And yet, that baby was amazingly hardy. I had many conversations with her mom and dad, and I remember telling them that their daughter had an unusual degree of resilience. She spent several months in the ICU before being released. But she grew up healthy, played soccer and has lived an active life. For years, I would get Christmas cards from the family, and I was always amazed.

Why are premature births so common?

We really don’t know. It’s the focus of a lot of scientific interest right now. There’s not one dominant thing that causes it — and rarely is it something the mother did herself. Lots of mothers think that if they had avoided x or y, their baby wouldn’t have been born prematurely. They blame themselves. We reassure them, though, that this is not something they’ve triggered or caused. Premature birth in 2015 is not preventable, at least not in the sense that some other medical conditions are preventable.

How does a chemical engineering major become head of a sophisticated neonatal intensive care unit?

After graduation, I was looking at jobs with several oil companies, as well as a position at Oak Ridge National Laboratory. But I also began considering alternative uses of my Georgia Tech education. My thoughts turned to becoming a doctor. So I decided to go to medical school at Emory and enjoyed every minute of it.

Do you see parallels between engineering and the practice of medicine?

You could say so about physiology, obviously, and that was an interest of mine. But what’s really important is the larger preparation Georgia Tech provides. It’s an education that prepares you to do anything you want. I think the encouragement to explore is one of the greatest features of the Georgia Tech environment. There’s a critical mass of folks you associate with as a student who encourage that type of broader thinking — not only faculty, but fellow students as well.

Did anyone in particular influence you?

I remember taking a course in cell biology and becoming fascinated with the life sciences because of my teacher. He ignited a spark intellectually – the sheer enthusiasm he had amplified my interest in medicine. I use that experience as proof of principle of the inadvertent influence teachers can have on their students. I also had a series of physical chemistry classes with a chemistry professor named Peter Sherry. I remember visiting him frequently, probably taking up too much of this time with all manner of questions about the class material. The fact that he would spend time with a student who otherwise would’ve been hesitant to bother a professor of chemistry really impressed me. Dr. Sherry had a generosity of spirit that I’ve tried to adopt in my career.

Where did your interest in science and technology come from?

I have always been attracted to why things work the way they do. My dad would replace the water pump on the car and re-pack the wheel bearings and repair the washing machine. Even at an early age, I was always asking him, “Why did you do it this way? What does this equipment do?” He was very patient in answering me.

What are some of the problems in neonatal care today that need fixing?

High on the list is a disease called necrotizing enterocolitis, or NEC. It’s the most common and serious intestinal disease among preemies. The tissue in the small or large intestine is injured or begins to die off, which causes the intestine to become inflamed or, in rare cases, develop a hole. When this happens, the intestine can no longer hold waste, so bacteria and other waste products pass through the intestine and enter the baby's bloodstream or abdominal cavity. This can make a baby very sick, and it often causes a life-threatening infection.

Might engineering play a role in addressing that challenge?

Interestingly, I’ve had conversations with the Georgia Tech Research Institute on that very point. They asked us an open question: What could GTRI do that would be of value? Our response had to do with developing some kind of signal that a baby is getting sick with NEC. Right now, there are no sufficient strategies to detect NEC early.

However, we know that in other health conditions, changes occur in exhaled gases. So we wondered: Could we apply that knowledge to develop an early-warning signal for babies acquiring NEC? Sensor technology is in the wheelhouse of GTRI engineers, but they may be looking for new ways for that technology to be applied. While it would be inaccurate to say we’re actively working on a project with Georgia Tech, we have opened up this dialogue.