Congenital Diaphragmatic Hernia
Click on Images for Enlarged View Clinical History: Full-term two day old female with dyspnea and cyanosis.
Findings: On the first study there is increased opacity of the left hemithorax with interspersed areas of lucency. The left hemidiaphragm is obliterated. The mediastinal structures are shifted to the right (note the endotracheal tube is also shifted to the right) suggesting the presence of a mass in the left hemithorax. Also note the absence of bowel gas within the abdominal region.
The next study done several hours later shows a large well- defined area of lucency in the left hemithorax representing swallowed air within the abdominal viscera.
Diagnosis: Congenital Diaphragmatic Hernia
Discussion: Congenital diaphragmatic hernias occur in about 1 out of 2,500 live births with a 2 to 1 male to female ratio. The most common form of congenital diaphragmatic hernia is the Bochdalek hernia. This type of hernia occurs in the posterior lateral segments of the diaphragm, more often on the left than on the right side. Herniation of abdominal viscera occurs through a defect in the diaphragm caused by failure of the pleural peritoneal canal to close completely during embryonic development. Varying degrees of herniation can occur. In severe cases the stomach and all of the intestines can protrude into the thorax. These patients will often have hypoplastic lungs due to crowding of the thoracic space. The ipsilateral lung is more severely affected than the contralateral one. They can also have associated anomalies such as malrotation, neural tube defects, and cardiovascular anomalies.
Most patients will present with symptoms at birth. They may show signs of severe respiratory distress such as dyspnea and cyanosis if herniation of abdominal contents is to such an extent as to cause hypoplastic lungs. Signs and symptoms of acute intestinal obstruction can also occur. The diagnosis is usually made by radiographic examination. Fluid and air-filled loops of bowel may be seen protruding into the chest with shift of mediastinal structures to the contralateral side. Occasionally the air- filled loops of bowel may mimic the appearance of multiple cysts and the differential diagnosis of cystic adenomatoid malformations of the lung must be considered. Treatment of this condition will entail respiratory support as well as surgical repair of the diaphragmatic defect. Nasogastric intubation with suction will decrease air and fluid within the abdominal viscera decreasing ventilatory compromise. Extracorporal membrane oxygenation (ECMO) may improve prognosis although mortality rate remains about 50%.
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David Chung, M.D.
Melissa Myers, M.D.
Rainbow Babies and Children's Hospital