A diaphragmatic hernia is a birth defect in which there is an abnormal opening in the diaphragm, the muscle that helps you breathe. The opening allows part of the organs from the belly (stomach, spleen, liver, and intestines) to go up into the chest cavity near the lungs.

A diaphragmatic hernia is caused by the improper joining of structures during fetal development. As a result, the abdominal organs such as the stomach, small intestine, spleen, part of the liver, and the kidney appear in the chest cavity. The lung tissue on the affected side is thus not allowed to completely develop.

Congenital diaphragmatic hernia is seen in 1 out of every 2,200 to 5,000 live births. Most affect the left side. Having a parent or sibling with the condition slightly increases your risk.

Severe breathing difficulty usually develops shortly after the baby is born, because of ineffective movement of the diaphragm and crowding of the lung tissue, which causes collapse. The reason why this occurs is not known.

Other symptoms include:

• Bluish colored skin due to lack of oxygen
• Rapid breathing (tachypnea)
• Fast heart rate (tachycardia)

The pregnant mother may have excessive amounts of amniotic fluid. Fetal ultrasound may show abdominal contents in the chest cavity.

Examination of the infant shows:

• Irregular chest movements
• Absent breath sounds on affected side
• Bowel sounds heard in the chest
• Abdomen feels less full on examination by touch (palpation)

A chest x-ray may show abdominal organs in chest cavity.

A diaphragmatic hernia is an emergency that requires surgery. Surgery is done to place the abdominal organs into the proper position and repair the opening in the diaphragm.

See: Diaphragmatic hernia repair - congenital

The infant will need breathing support until he or she recovers from surgery. Some infants are placed on a heart/lung bypass machine, which gives the lungs a chance to recover and expand after surgery.

If a diaphragmatic hernia is diagnosed during pregnancy (around 24 to 28 weeks), fetal surgery may be considered.

Congenital diaphragmatic hernia is a very serious disorder. The outcome of surgery depends on how well your baby's lungs have developed. Usually the outlook is very good for infants who have enough lung tissue.

With advances in neonatal and surgical care, survival is now greater than 80%.

• Lung infections
• Other congenital problems

Go to the emergency room or call the local emergency number (such as 911). A diaphragmatic hernia is a surgical emergency.

There is no known prevention.

Ehrlich PF, Coran AG. Diaphragmatic hernia. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 101.