David Kays, M.D., likes to think about things in a different way.

He questions whether the generally accepted method really produces the best outcomes. He looks in the mirror and challenges himself.

“I'm very self-critical,” says Kays, a pediatric surgeon at Johns Hopkins All Children’s Hospital in St. Petersburg, Florida. “I look at myself and say, ‘Kays, you could have done better.’”

That critical thinking and personal motivation have led Kays to become one of the best in the nation at treating congenital diaphragmatic hernia (CDH), a condition that affects about one in 3,000 pregnancies. The muscle that separates the baby’s abdomen from the chest doesn’t form correctly, leaving a large hole that allows the abdominal organs to move up into the chest. This limits room for the lungs to grow, resulting in critically small lungs in severe cases. CDH generally is diagnosed midway through pregnancy, and many expectant mothers receive a recommendation that they terminate the pregnancy.

Kays believes that virtually all babies with CDH can survive and thrive. He has treated nearly 600 CDH babies in his career. He and the team he has built as medical director of the Center for Congenital Diaphragmatic Hernia at Johns Hopkins All Children’s — the nation’s first and only inpatient unit solely dedicated to treating CDH — have a survival rate in severe cases above 90%, compared to national survival rates of 50% or less.

Through experience and more than two decades of research, Kays has developed a sense for timing the repair and managing the baby’s ventilation that provides the lungs and the brain the best chance to grow and develop.

“Doing the repair surgery does not make small lungs into big lungs,” Kays says. “Our goal is to allow small lungs to be as big as they can be.”

Kays talked recently about his interest in medicine, what attracted him to CDH care and what he does away from the hospital.

Did you always want to be a doctor?

I did. I remember my mom gave me a book called The Making of a Surgeon. It was written by a guy named William Nolen. I read that and it just seemed to fit, but I was like 10 years old. I always wondered what was going on when an ambulance went by, and I just always was fascinated by medicine. I started working in an emergency room in high school because I always liked the emergencies and life-threatening nature of the illness and wanted to be involved in that part of medicine.

How did you come to specialize in CDH?

I always had an interest in critical care and in respiratory physiology and ventilators and lungs. I was always at my best in those critical care situations. I recognized it, and the people I worked with recognized it. Diaphragmatic hernias became a great way in pediatric surgery to express that critical care interest and kind of the facility that I had developed. It was just a good fit and a chance to save lives like I always wanted to do. Diaphragmatic hernia really became that outlet, and it was an unsolved problem that needed attention.

The big thing with diaphragmatic hernia — while there are technical things that matter — is really critical care. How do you take care of kids whose lungs are fundamentally very, very small? That was an unsolved problem. I like to think differently. When I was training and learned things, I wondered how did things evolve that way? Why are they still that way? Is it because that's the best way? Was it because somebody started that and everybody just did what that person said, and now that has become the standard way? I think one of the things I'm good at is looking at what somebody does and asking the question: Is that really the best way to do it and can we think about this in a different way and get a better outcome? And diaphragmatic hernia allows that way of thinking to kind of be rewarded because the truth was, we did need some new ways to think about it.

What attracted you to come to Johns Hopkins All Children’s in 2016?

I needed a place on an upward trajectory that had room to grow. This hospital had become part of Johns Hopkins a few years before and had a vision and an interest in developing national programs. I thought together we could do something really special. [In 2016, Kays treated 17 CDH patients at Johns Hopkins All Children’s. More recently, the program is seeing 50-60 patients a year with families coming from more than 30 states.]

It’s not hard to understand the impact of CDH on the lungs, but you make a point of also addressing these babies’ brain development. How does CDH impact that?

CDH leads to small lungs. Small lungs can lead to low oxygen levels. So, it really is an oxygen delivery issue. We have to deliver enough oxygen to the brain throughout the whole course of management to have good brain outcomes on the other side. We know quite clearly that the number of kids we save is about how well we take care of their lungs. But we also know that the quality of that outcome — who they are when they go home — is all about how well we take care of their brain. There are identifiable times during care where the brain is most at risk, and by thinking about the brain all the time, we can learn to anticipate and mitigate those risks, resulting in better outcomes … not just regarding survival, which is a very blunt tool to measure outcomes by, but in functional brain outcomes as well. Every baby we treat in our program gets a brain MRI and a neurodevelopmental test at discharge. It’s our own internal brain protection scorecard.

What do you do to take your mind off work?

I work a lot, which is a passion. Although it's very tiring, I don't get tired of it. I have a boat. I am a novice when it comes to boating, but I love being out on the water. I thought I knew a little bit about fishing, but I don't know diddlysquat. I learned to fish from my dad who took us to a trout farm where all you had to do was throw a hook in and a thousand fish would try to eat it. That's not what happens out in the Gulf of Mexico. I'm not very good at fishing.

I love to play golf because it gets me outside, but I don't get to play very often. I have three grandkids, and they are fun. But they don't live in town.

The Center for CDH team keeps expanding. What are your plans moving forward?

I think my role in the next 10 years is going to be to continue to operate and continue to be at the bedside, but also to spend more time in front of a computer writing about what I've learned so other people can improve their game. That may mean I'm not spending quite as much time at the bedside, but I trust the team.

I know that I bring a level of experience to the bedside that most other people don't have, but our team has great expertise in a variety of specialties, and we are building their experience with CDH. That is what the dedicated Center for CDH allows us to do.