Congenital Diaphragmatic Hernia (CDH)

What is congenital diaphragmatic hernia (CDH)?

Congenital diaphragmatic hernia (CDH) is a rare condition that is characterized by a defect in the diaphragm. The diaphragm, which is made up of muscle and fibrous tissue, separates the organs in the abdomen from those in the chest. An absent or partially formed diaphragm results in an abnormal opening (hernia) that allows the stomach and intestines to move into the chest cavity and crowd the heart and lungs. This crowding can lead to underdevelopment of the lungs (pulmonary hypoplasia), potentially resulting in life-threatening breathing difficulties that are apparent from birth. CDH cases are often classified by their position. The two most common are:

• Bochdalek hernias: a defect in the side or back of the diaphragm. Between 80 and 90 percent of congenital diaphragmatic hernias are of this type.
• Morgnani hernias: a defect involving the front part of the diaphragm. This type, which accounts for approximately 2 percent of cases, is less likely to cause severe symptoms at birth.

What are the symptoms of congenital diaphragmatic hernia (CDH)?

Symptoms of Bochdalek CDH include:

• Difficulty breathing
• Fast breathing
• Fast heart rate
• Cyanosis (blue color of the skin)
• Abnormal chest development, with one side being larger than the other abdomen that appears caved in

A baby born with a Morgagni hernia may or may not show any symptoms, but if shown, the symptoms are similar to that of Bochdalek hernias.

What causes congenital diaphragmatic hernia (CDH)?

While it is currently unknown exactly what causes CDH, scientists believe that multiple genes from both parents, as well as a number of environmental factors, play a role in the onset of the condition. 

How is congenital diaphragmatic hernia diagnosed (CDH)?

Examination in infants with congenital diaphragmatic hernias include the following observations:

• Scaphoid abdomen
• Barrel-shaped chest
• Respiratory distress
• Associated anomalies: Dysmorphisms such as craniofacial abnormalities, extremity abnormalities, or spinal dysraphism may suggest syndromic congenital diaphragmatic hernia

In addition, tests to confirm a diagnosis of CDH include:

• Arterial blood gas measurements
• Chromosome studies
• Levels of serum electrolytes, ionized calcium, and glucose
• Chest radiography
• Cardiac ultrasonography
• Echocardiography
• Renal ultrasonography
• Cranial MRIs and sonography

What are the treatments for congenital diaphragmatic hernia (CDH)?

Medical therapy in patients with congenital diaphragmatic hernia is directed toward optimizing oxygenation while avoiding barotrauma. This management includes the following:

• Placement of a vented orogastric tube and connecting it to continuous suction to prevent bowel distention and further lung compression
• Avoiding mask ventilation and immediately intubating the trachea
• Avoiding high peak inspiratory pressures with mechanical ventilation; synchronizing ventilation with the infant’s respiratory effort
• Continuous monitoring of oxygenation, blood pressure, and perfusion
• Maintaining glucose and ionized calcium concentrations within reference range

Surgical procedures can also be used to fix the abnormally-formed diaphragm, alleviating many of the associated symptoms and complications.

Where can I find out more about congenital diaphragmatic hernia (CDH)?

• Boston Children’s Hospital
• NIH
• Medscape