Congenital diaphragmatic hernia (CDH) occurs when the diaphragm, a muscle that separates the abdominal and chest cavity, fails to close during the fetal period. The abdominal organs herniate to the chest cavity through these openings and impact the growth of the lungs.
CDH may result in pulmonary hypoplasia (smaller lung than usual) and pulmonary hypertension (high lung blood pressure) in many babies. Immediate medical care may help to prevent complications of CDH after birth.
Read this post to know about the causes, types, symptoms, complications, diagnosis, and treatment of congenital diaphragmatic hernia (CDH) in babies.
Causes Of CDH In Babies
The causes of CDH are unknown in many babies. Some research suggests that genetic factors may cause CDH, especially when it occurs with other birth defects, such as congenital heart defects. However, CDH may also be an isolated anomaly in some babies with no other genetic defects (1).
Source: Centers for Disease Control and Prevention, National Center on Birth Defects and Developmental Disabilities
Types Of CDH
CDH can be of two types (2).
- Posterolateral Bochdalekhernia is the common type, occurring due to a hole in the diaphragm’s back.
- Anterior Morgagnihernia occurs due to a hole in the front of the diaphragm. This type of hernia has less impact on lung growth.
Hiatus hernia is a condition where the stomach’s upper part moves into the chest cavity through the diaphragmatic opening. This is common in adults and rarely seen as a congenital defect.
Signs And Symptoms Of CDH
The following signs and symptoms are seen before birth on the prenatal ultrasound.
- Fluid in the chest
- Displaced heart
- Herniation of liver, intestines, and stomach to the chest cavity
Babies born with Morgagnihernias rarely show symptoms. Bochdalek hernia could cause the following signs and symptoms in newborns (3).
- Fast breathing(tachypnea) or breathing difficulties
- Increased heartrate (tachycardia)
- Bluish skin or cyanosis
- Barrel-shaped chest or chest with abnormal shape, such as one side may look more extensive than the other
- Caved in or scaphoid appearance of the abdomen
- Symptoms of respiratory distress such as grunting respiration and chest retractions
- Congenital anomalies are also seen in many babies with CDH
Respiratory distress and cyanosis immediately or a few minutes or hours after birth can be commonly seen in babies with severe CDH. Some may require aggressive resuscitation due to circulatory insufficiency.
Complications Of CDH
Severe CDH, especially Boch dalek hernia, could be associated with the following complications in some babies (2).
- Failure to thrive due to lung problems
- Inability to feed, requiring feeding through tubes to meet nutritional needs
- Chronic lung diseases requiring oxygen supplementation and medications for a long time
- Pulmonary hypertension due to poorly developed blood vessels in the lung may impactoxygen supply
- Developmental delays
- Gastroesophageal reflux can be expected due to abnormal positioning of the stomach
- Hearing impairment may also occur in some babies with CDH
Complications may vary based on the severity of the CDH. Early interventions may help to prevent some of these complications in a few babies.
Diagnosis Of CDH
CDH is diagnosed during prenatal ultrasound since the abdominal organs, such as the stomach, liver, and intestine, may be seen in the chest cavity. These abdominal organs may push the heart to one side.
The following imaging techniques are often ordered to confirm the prenatal CDHdiagnosis (1).
- High-resolution fetal ultrasound to evaluate the fetal anatomy and CDH
- Fetal echocardiogram to assess structure and functions of the fetal heart
- Ultrafast fetal MRI also helps to visualize the anatomy and CDH
These tests identify the affected part of the diaphragm and the displaced organs. CDH may affect the left, right, or both sides of the diaphragm. The impact of CDH on the lungs is also noted to estimate the consequences after birth.
Outcomes Of CDH In Babies
The location of the liver can often help determine the severity and outcomes of CDH. Pulmonary hypoplasia (small lungs) is the most common complication due to the liver’s displacement in the chest cavity. The following prenatal ultrasound or MRI measurements help determine the degree of pulmonary hypoplasia.
- LHR (lung area to head circumference ratio)
- LHR O/E (lung area to head circumference observed or expected)
- MRI O/E (total lung volume observed to expected)
These measurements may help determine the lungs’ volume (size), but not pulmonary hypertension that affects the lung function after birth. A baby with left side CDH, the most common type, may have a displaced heart due to herniation of the stomach and intestines to the chest cavity. Sometimes the liver may also herniate in the left side CDH. However, the right side CDH allows herniation of a significant part of the liver into the chest cavity.
Treatment Of CDH
Treatment options may vary depending on the severity of CDH and the age of the baby. The treatment can be prenatal or postnatal and may includethe following (4).
1. Management during pregnancy
You may receive a referral to a maternal-fetal medicine specialist and a pediatricsurgeon if the prenatal ultrasound shows signs of CDH. The obstetric team managing CDH pregnancies may observe the CDH pregnancies every four weeks until the last trimester and every week after that.
Lung measurements and amniotic fluidvolume is measured on ultrasound during the prenatal period. If the CDH is severe fetal surgery is considered. Fetoscopic endoluminal tracheal occlusion (FETO) is a fetal surgery for CDH. Treatment before birth could help the baby’s lungs grow correctly and avoid life-threatening complications.
2. Delivery of babies with CDH
If the CDH is diagnosed during the prenatal period, delivery is planned in a specialty hospital since the baby may require medical care immediately after birth. Most babies with CDH are delivered vaginally in term if there are no obstetric issues for a cesarean section.
Many newborns with CDH are transferred to neonatal intensive care units for postnatal care. Breathing tubes and a ventilator (breathing machine) are connected to babies with respiratory distress. A nasogastric or orogastric tube is also inserted to keep the stomach decompressed since this may help the lungs expand. Twenty-four hours of observation in NICU is done for most babies with CDH.
3. Surgical repair of CDH
Surgical repair of CDH is done through an incision below the rib cage. The time and type of surgery may vary based on the severity and health status of the baby. Medications and inhalation therapies are also given before surgery to enhance lung function.
A Gore-Tex patch or a muscle flap is used to close the diaphragmatic opening, depending on its size. Larger openings require patch repair since muscle flap may not be able to cover it. Regular follow-up is done for a few years to observe lung growth in babies.
4. NICU stay for babies with CDH
Babies are kept in NICU since these facilities are immediately available for stabilization. Nitric oxide, high-frequency oscillatory ventilation (HFOV), and ECMO (heart-lung machine) are often required for CDH management.
HFOV can deliver air and pressure against pulmonary hypertension than standard ventilators. ECMO machines take over the functions of the heart and lungs in the body. This provides rest to the lungs and avoids complications due to inadequate lung and heart functions in babies.
The length of hospital stay and outcomes may vary based on the severity of CDH. Most babies recover from CDH soon after the surgical repair and can lead a normal life. Usually, many babies may require follow-up care to enhance lung growth and development.
Frequently Asked Questions
1. Is it possible to breastfeed a baby with CDH?
Some babies with less severe CDH can be breastfed without any complications. However, babies receiving extracorporeal membrane oxygenation (ECMO) may not be able to breastfeed. They may need parenteral nutrition since nothing by mouth (NPO) is indicated during ECMO. After CDH repair and removal of ECMO, they can be breastfed.
2. How long do babies with CDH live?
The life expectancy of a baby with CDH may vary depending on the hernia’s type and severity. Babies with severe lung dysplasia may have reduced life expectancy than others. However, most babies can catch up with the lung growth after repair since the lung may grow until eight years of age. Timely treatment, regular follow-ups, and special therapies may help to achieve normal life expectancy after CDHrepair in many babies.
3. Can CDH be misdiagnosed?
CDH could be misdiagnosed in some babies since the signs and symptoms are not specific for this condition. This may often occur if there is a late presentation of signs and symptoms. CDH could be often misdiagnosed as pneumonia, pneumothorax, pulmonary effusion, and congenital pulmonary anomalies in some babies. This may often result in unnecessary medical interventions in some cases.
Congenital diaphragmatic hernia (CDH) occurs at birth but can be diagnosed prenatally through ultrasound. The postnatal treatment and management could depend on the severity of the condition and the presence of other anomalies. Timely treatment could improve outcomes, and the baby could have normal long-term lung and heart functions.