About Congenital Diaphragmatic Hernia (CDH)
Congenital Diaphragmatic hernia (CDH) is a fetal abnormality that occurs very early in pregnancy (10-12 weeks), in which the baby’s diaphragm does not form properly. An opening in the diaphragm leads to contents of the abdomen — such as the stomach, small intestine, spleen, liver or kidney — developing in the chest cavity instead of the abdomen. These displaced organs prevent the lungs from normal development. When the baby is born, the lungs are often small and do not work as well.
This graphic shows a baby with CDH. An opening in the diaphragm leads to organs developing in the chest cavity and prevents the lungs from developing as normal.
CDH is rare, occurring in one out of every 2,500 to 3,000 births. It varies in severity from mild, causing no neonatal effect at all, to very severe, causing immediate distress and sometimes death. CDH is not related to anything the mother did or did not do during pregnancy.
At the SSM Health Cardinal Glennon St. Louis Fetal Care Institute, we understand the anxiety and worry you may have about a diagnosis of CDH. Our SLUCare Physician Group doctors are specially trained to help you and your baby, providing the timely treatment that puts you at ease and gives your baby the best start in life.
The Comprehensive CDH Care Team provides babies with CDH seamless care from the prenatal diagnosis, to neonatal surgical care, to ongoing care through the school-age years.
What You Need to Know About CDH
CDH is typically detected through a routine ultrasound, which allows doctors to check the position of your baby's lungs and heart. Following the initial diagnosis, at 22 to 28 weeks of gestation, the SSM Health St. Louis Fetal Care Institute team performs a focused ultrasound, a fetal MRI, and a fetal echocardiogram (echo) to assess the severity of the CDH. We also offer genetic testing to determine if a chromosomal abnormality has caused the CDH. In some situations, additional testing will be required throughout the pregnancy.
The team uses several measurements to understand how the CDH will affect the baby. We measure the lung-to-head ratio (LHR), the liver position, the total lung volume, and the response of the fetal lungs to oxygen. Additionally, we look for any abnormalities that suggest a genetic cause. This critical assessment can often provide insight into the severity of the CDH.
Every case and every outcome is different; however, the liver position and lung-to-head ratio can often be a predictor of the severity of the CDH. “Liver up” means that the liver has migrated through the hole in the diaphragm into the chest cavity, while “liver down” means that it is below the hole in the diaphragm, sitting in the normal position in the abdomen.
Most babies with less severe CDH can be delivered vaginally at full-term, unless there are obstetric indications for cesarean delivery. It is best for these babies to be delivered at a medical center where there is access to a team of pediatric surgeons and neonatologists, along with an established Neonatal Intensive Care Unit (NICU), like that at SSM Health St. Mary’s Hospital - St. Louis.
At birth, the neonatology team will assess your baby. If necessary, a breathing tube will be inserted and a nasogastric tube will be inserted into the stomach to prevent air from building up in the stomach and intestines. Most babies with CDH will go to SSM Health Cardinal Glennon Children’s Hospital for intensive monitoring prior to surgery.
In severe cases of CDH, we may recommend a special delivery procedure, called an EXIT procedure. If your baby has the signs of a severe CDH, we can discuss the full range of options to care for your baby.
The care of babies with CDH can be quite complex, with frequent blood tests, x-rays and machines that are helping to support your baby. Our team will involve and inform our parents about all of the various aspects of their baby’s care. We encourage parents to ask questions to better understand how their baby is responding.
When babies with CDH arrive in the NICU they begin the observation stage of their care until they are ready for hernia repair surgery. In many situations they are kept on a ventilator and given sedation to keep them calm and pain free. Intravenous fluids and nutritional support are also provided. Your baby will not be able to eat until after surgery. If they choose, mothers can pump and store their breast milk until the baby can eat.
Most CDH babies suffer from high blood pressure in the lungs, called pulmonary hypertension. This problem can be quite serious and can delay surgical repair of the diaphragm. Before repair surgery, your baby will be monitored for pulmonary hypertension, and treatments will be started to reduce its severity. For instance, inhaled nitric oxide is often used to help open up the blood vessels in the lungs, decreasing the blood pressure and allowing for better oxygen delivery.
CDH babies typically undergo surgery to repair the hole in their diaphragm once pulmonary hypertension has subsided. The CDH team will work together with you to develop the optimal care plan for you and your baby.
During surgery, the surgeons will assess the size and location of the defect to determine which type of closure is required. During the CDH repair procedure a small incision in made under the rib cage to give the surgeon access to the diaphragm and misplaced organs. The surgeon will gently reposition the organs in the abdomen, and close the hole in the diaphragm. Smaller hernias may be repaired with stitches, but larger defects require a medical patch.
After surgery, your baby will return to the NICU to recover and heal. The stress of the surgery may cause your baby’s condition to initially get worse before it gets better, and treatment may require additional sedation, ventilation, blood pressure medications or ECMO.
The amount of time spent in the NICU after surgery varies from patient to patient depending on the severity of their case. The CDH team will work to wean your baby off the ventilator and pain medications as quickly as possible, and to get them eating and gaining weight.
In some cases, the pulmonary hypertension (high blood pressure in the lungs) is so severe that the blood cannot get to the lungs to exchange oxygen. This can threaten the baby’s life. Extracorporeal Membrane Oxygenation (ECMO) can be used in some situations to allow the baby to rest, and let the hypertension resolve on its own.
ECMO is a machine that functions just like the heart and lungs, exchanging gases like oxygen and carbon dioxide. The neonatologists and pediatric surgeons watch your baby very carefully to determine if ECMO is needed. If so, then surgery is needed to place the baby on ECMO. This is a serious intervention with a lot of potential risks. Your doctors will discuss these risks with you, so that you can decide if ECMO is right for your baby.
Not every hospital has the expertise necessary to offer ECMO, but this treatment is available at SSM Health Cardinal Glennon if it becomes necessary.
CDH is a complex condition that requires long-term follow-up care. Because CDH can cause underdeveloped lungs and problems with the heart and digestive system, it’s important to monitor your baby’s health throughout their development.
Once you go home, a Collaborative CDH Care Program coordinator will assist with scheduling your baby’s follow-up clinic appointments and any future medical procedures or surgeries that may be needed. This continuum of care ensures that the specialists working with our CDH patients know the intricacies of your child’s unique medical situation and can provide the best level of care.
A few weeks after being discharged from the NICU your baby will return for a follow up visit with the CDH Care and Nursery Follow Up teams. Based on your baby’s needs related to nutritional support and growth/development, you may be referred to the the Glennon Intestinal Rehabilitation and Feeding (GIRAF) team for additional follow up. This team can provide ongoing, coordinated care to ensure adequate nutrition throughout your child’s development.
The CDH care team typically sees babies and children with CDH several times during the first few years of life, and then follow-up visits are determined by your child’s individual condition. Follow-up visits typically involve an appointment with the pediatric surgeon. A chest x-ray is done to ensure there is no re-herniation and the lungs are growing/expanding well.