An Improving Outlook for Babies With Congenital Diaphragmatic Hernia (CDH): A Q&A With Dr. Rebecca Stark

Rebecca Stark, MD, FACS, is a board-certified pediatric surgeon in the Division of Pediatric General and Thoracic Surgery at Seattle Children’s and an Assistant Professor of Surgery at UW.  She is director of the Congenital Diaphragmatic Hernia Program and surgical co-director of the ECMO Program at Seattle Children’s.

What is CDH?

Dr. Stark: When a baby’s diaphragm doesn’t form completely before birth, it leaves a hole between their abdomen and chest. Organs that should grow in the belly go through the hole up into the chest. Babies with CDH have small lungs as a result, and the lung tissue itself is different. Babies with CDH may have serious breathing problems starting soon after birth, as well as a low blood pressure and elevated heart rate.

What causes CDH? Are some children more at risk?

Dr. Stark: CDH comes from mutations in genes, many of which are unknown, which lead to abnormal diaphragm development. Some genetic syndromes are associated with CDH, but those affect the minority of patients, and the genes aren’t handed down by parents. We don’t know of any specific risk factors for developing CDH. It can occur in any baby. Most moms are completely healthy. It’s usually a big shock that their baby has CDH.

How is CDH diagnosed?

Dr. Stark: It typically appears on the pregnant mother’s 20-week ultrasound. After it’s detected, we do additional tests to assess the baby’s condition further and determine how mild, moderate, or severe the case is. In rare cases (about 1 to 3 times a year among the patients we see) CDH occurs after 20 weeks and is only discovered after the baby is born. These babies tend to do exceptionally well because their lung tissue is much more developed by the time the hole in the diaphragm develops.

What is the outlook for a baby with CDH?

Dr. Stark: While CDH can be life-threatening, the vast majority of babies survive and go on to recover fully and do well. Data shows that CDH centers that have a high volume of patients, like ours (we see 15 to 20 new patients per year), offer the best survival rates.

The survival rate for children we have treated for CDH over the last 3 years is 90% – significantly better than the national average.

While in the hospital, a baby with severe CDH will have a very different course than a baby with a milder case. Babies with severe CDH can have a four to six month hospital stay, a long period of care on a ventilator and extracorporeal membrane oxygenation (ECMO). They are likely to return home on oxygen and with a nasogastric (NG) feeding tube. Babies with milder cases won’t need a long time on the ventilator or any time on ECMO and can be home in about a month, breathing and eating normally on their own.

How does Seattle Children’s care for these babies?

Dr. Stark: We have a whole program of specialists dedicated to providing multidisciplinary care to these babies and supporting their families from before birth right up to adulthood. I can’t emphasize strongly enough that it is our multidisciplinary approach, experienced team, and evidence-based care pathway that is the key to achieving the exceptional outcomes we have.

CDH affects so many organ systems that you need a team who specializes in each of those areas working together. We have dedicated CDH cardiologists, who are pulmonary hypertension specialists as well as neonatologists, surgeons, and dietitians, nutritionists, physical therapists and nurses who are all dedicated just to caring for CDH patients.

Our basic timing is:

• Before birth, we meet with the parents to get to know them better and answer their questions. We conduct prenatal imaging around 22 and 32 weeks at our prenatal center to assess the baby’s condition and prognosis, and work closely with the mother’s primary OB and MFM teams during pregnancy to coordinate care. Most mothers deliver at UW where we have a level 4 NICU and then are transferred to the level 4 NICU at Seattle Children’s. We are national leaders in safely moving fragile newborns.
• Newborns stay in the NICU on ventilator support until they undergo surgery (when it is safe to do so) and receive ventilator and ECMO support as needed. In addition to daily multidisciplinary rounds, each baby’s care is thoroughly discussed by the entire CDH team during weekly CDH conference.
• After discharge, babies are seen at our follow-up clinic throughout their childhood to monitor for problems and keep them as healthy as possible.

What should OBs or other providers tell parents when their baby is diagnosed with CDH?

Dr. Stark: A CDH diagnosis is very difficult news for parents. Many come to their first appointment with us burdened by worry and misinformation. We suggest telling them:

• Most babies will survive and live normally, despite what might be an intense and lengthy stay in the hospital at first. Seattle Children’s routinely sees healthy 1- to 4-year-olds for follow-up who are meeting all their milestones, going to school, playing sports, etc.
• Survival rates are very high today, and rising. CDH is not a death sentence or a 50-50 chance of survival, as many parents are initially told. Seattle Children’s has a survival rate of 90% for CDH babies in the last 3 years (ours is significantly higher than the national average).
• We have really good predictive prenatal tools to help them understand what they are facing. CDH is a spectrum of disease. We have tools to tell us how severe the baby’s CDH is and even how long they will be in the hospital and what care they will need.
  • At 20 to 24 weeks we will do an MRI, fetal echo and ultrasound that allow us to give parents very specific counseling and projections (parents considering terminating the pregnancy have until 24 weeks).
  • A second MRI at 32 weeks will give us even stronger information that can help us predict how much time the baby will need to spend in the hospital after birth, whether a ventilator or ECMO will be needed and the baby’s overall survival chances. We don’t get many surprises at 32 weeks although in some cases a baby goes from moderate to severe during this time (between 22 and 32 weeks) and we will counsel the family and adapt our care plan accordingly.
• “You can do this.” Parents wonder how they’ll cope, because it feels so overwhelming. The answer is step by step. In our experience, by the time they take their baby home, parents are all experts in CDH and what to look for and expect, regardless of their background or education.
• No Googling. Parents are advised not to read about CDH on the Internet before meeting with their CDH doctor, as the information is likely to be wrong and add unnecessarily to their stress.

How important is having a clinical pathway for CDH?

Dr. Stark: I would recommend a family avoid any program that didn’t use a treatment pathway. That being said, CDH is the kind of disease where an experienced team is very important for managing the many subtle but important details that you can’t possibly cover in the pathway. There are minute-by-minute variations in how we manage the babies that can make a huge difference in their outcome. Oftentimes, there’s no one single number you can look to when making a decision; rather, it’s many things about the baby at any given time. It’s our experience, teamwork and knowledge-sharing that guide us in these situations.

Has your program changed recently?

Dr. Stark: The fact that we have official program designation is actually fairly new – just two years old. We treated CDH babies prior to that for many years, but without a program framework to knit it all together nor the long-term treatment strategy we have today, which supports these children from before birth until they reach adulthood.

I was hired two years ago to lead and grow the program which was started 20 years ago by Dr. Dan Ledbetter, who passed away unexpectedly right after I came.   He had a vision to unify all the different aspects of care for these patients from prenatal to long term follow up and that is what we have recently achieved, along with the following:

• National CDH registry: We are now part of the national CDH registry, which is a huge deal. It allows us to get our patient data uploaded to a national database where we can compare outcomes to other institutions and access others’ data for our research projects. Most busy centers only see 10 to 20 patients per year. The ability to combine data across 80+ hospitals means we can study things we never could in the past.
• Fetal MRIs for diagnosis and planning: In addition to fetal ultrasounds, we now offer fetal MRIs. Compared to fetal ultrasounds, MRIs give a much clearer picture of how much lung the baby has, and they help us to predict what level of care the baby will need. MRI lung measurements are critical because it’s not the hole in their abdomen that is the real problem, it’s how the impinging organs affect the baby’s lungs and sometimes their heart function also.
• Family connections: We meet with families sooner and more often than we did before. Our prenatal consults used to be one visit between the family and a pediatric surgeon. Now more of us get to visit with the family before the baby is born. We do at least 2 prenatal visits with the family, and these are coordinated with a neonatologist and our pulmonary hypertension specialist Dr. Delphine Yung and Emma Jackson ARNP in cardiology, who are really important members of the CDH team. Getting to know the family this way helps us improve care for them and their baby too.
• Staffing and resources: Seattle Children’s has prioritized the CDH program and provided the resources we need to offer world-class care, including a dedicated nurse practitioner, Carrie Foster ARNP, a CDH nurse for our patient support, Allie Schneider, and a care coordinator who can guide families through their whole experience.
• Provider continuity for families. We now have the same provider team working with the baby and family from before birth through delivery and newborn care as well as in our long term follow up clinic.
• Long-term follow-up care: We follow CDH kids through their adolescence with a team that includes multiple pulmonologists, Dr. Yung and Emma Jackson, ARNP from cardiology, two of our surgeons, Carrie Foster, ARNP, a dedicated dietitian, and another nurse who helps to coordinate everything. It’s a much stronger resource for families. Not many other programs offer long-term follow-up care for these kids, including some high-volume centers.

Why is long-term follow-up care needed?

Dr. Stark: Some of the things we are looking for so that we can proactively manage them include:

• Pulmonary hypertension
• Reactive airway disease
• Chest wall abnormalities
• Scoliosis/spine deformations
• Re-herniation of their diaphragm patch repair (Seattle Children’s has one of the lowest rates in the world for repeat hernia surgery for CDH patients)
• Bowel or partial-bowel obstruction
• GERD
• Neurodevelopmental deficits
• Nutritional deficits requiring nutritional counseling from a specialist

All these conditions are manageable if we catch them before they become a major problem. Kids in our follow-up clinic get better and better over time, and eventually in their teens their follow-up becomes just an annual check-in.

Are CDH outcomes improving?

Dr. Stark: Yes! Ten years ago, we would parents that their baby had a 60% to 70% overall survival chance. Now it’s 90% here! That’s because we have really refined our approach and worked hard to create a standard pathway for managing CDH, which, importantly, includes very precise ventilator management. If kids can’t ventilate well, they will require ECMO, which is stressful and comes with its own complications, like bleeding, that can lead to worse outcomes.  We try to keep babies off ECMO if we can.

Dr. Bob DiGeronimo, our NICU medical director and CDH team member, has been fine-tuning how we run the ECMO for these babies. There are very subtle things we can do to make it less stressful for babies, minute to minute and hour to hour, that you just can’t detail in a pathway. This level of ECMO expertise is something that is unavailable in many other places in the region.

How does ECMO factor into a baby’s care and outcomes?

Dr. Stark: Ideally, we don’t want a baby to need to go on ECMO because that means their problems are, or have become, severe. Plus, ECMO has its own set of complications and long-term neurodevelopmental issues.  Outcomes are generally worse for babies that go on ECMO; their survival rate nationally ranges between 40% and 60% depending on where they get care.

• At Seattle Children’s, we see the same severity of CDH disease that other hospitals see but only 15% to 18% of our babies need to be put on ECMO, which is about half the national average rate of 30%.
• For our babies who do go on ECMO, survival rates were good before we became an official program, i.e. close to 60%. Over the past three years, however, we’ve driven that number even higher and now have a 71% survival rate for our babies on ECMO. We attribute this to having a dedicated multi-disciplinary team that is experienced in taking care of CDH babies and has members that work really well together.

Our ECMO program is designated an Extra Corporeal Life Support (ELSO) Center of Excellence and regarded as the best in the Pacific Northwest.

What’s new on the horizon for CDH?

Dr. Stark: A lot of research is being done to better manage CDH babies and improve their outcomes further. We expect to continue incorporating the latest research findings into our pathway. Beyond that, we are in the early stages of planning a fetal intervention program with our MFM colleagues that would allow us to treat a subset of babies with severe CDH prenatally. The procedure involves inserting a balloon into the airway of the fetus in order to block it, which forces their lung to grow. Just a few other places are doing this in the United States currently. In the appropriate patients, it appears to significantly affect their outcome.

How should parents decide where to get care for their CDH child?

Dr. Stark: Parents should look for a program that sees a high volume of patients and has an experienced, multidisciplinary team, like ours. They should follow evidence-based practices that stay on the leading edge of treatment, as the CDH field is changing quickly. Ideally, the same team members who work with the babies are also doing research so that providers are combining the best of the clinical and research worlds for their patients.

What makes the Seattle Children’s CDH program exceptional nationally is our strong commitment to staying at the forefront of CDH care and maintaining a world-class program. I can unequivocally say we offer care that is as good as or better than anywhere else in the country. We welcome your referrals.

What research is underway at SCH?

Dr. Stark: As part of the national CDH registry we are using national data to look at how prostacyclin (a medicine used to relax the vessels in the lungs) can help keep babies off of ECMO.  We have an additional registry study looking at perfusion studies (blood distribution to lungs) in CDH toddlers and how it can help us predict long term lung function.  We recently published a study looking at dysphagia (difficulty with coordinated swallowing) in babies with CDH and ways in which to prevent aspiration in these babies.  These studies by our CDH team will ultimately fine-tune the way CDH babies are cared for everywhere.

How can providers get in touch with you?

Dr. Stark: We welcome providers’ calls and inquiries any time.

• If you have questions about making a referral, please call our Prenatal Nurse Coordinator Line at 206-987-0134, or email us at PrenatalClinic@seattlechildrens.org.
• If you have questions about our CDH program, please email us at CDHprogram@seattlechildrens.org.
• For urgent assistance from one of our doctors, call the hospital’s Provider-to-Provider Line at 206-987-7777 and ask for the on-call prenatal specialist.

Once we learn about a mom whose baby has CDH, we will arrange an initial appointment within 24 hours.

Can families tour the CDH program and NICU?

Dr. Stark: Absolutely. This can be arranged through the prenatal center.

What drives your interest in caring for babies with CDH?

Dr. Stark: I think CDH is a complicated disease that can be very challenging to manage, and I find that very interesting! But the really special thing about the CDH program is that we get to know the babies and their families very well; we meet the parents before they even have their precious baby, then perform surgery on their baby to repair the diaphragm right after birth, then care for them as an inpatient and finally follow them in our CDH clinic for the rest of their childhood. I feel fortunate to get to participate in that journey. Some patients that we see in clinic are teenagers! And it’s very rewarding to see parents, who endured so much at the beginning, end up with a healthy, happy child.

Learn More

• Seattle Children’s CDH Program and our Team 
• Treating Congenital Diaphragmatic Hernia – Seattle Children’s (seattlechildrens.org)