Several pediatric surgical lesions may lead to a respiratory distress syndrome in the newborn.
Such is the congenital diaphragmatic hernia, a classical and life-threatening malformation which occurs in its most common type once in 2000 and more newborns. About 10 to 20 percent of the congenital diaphragmatic hernias are asymptomatic in the newborn and may be discovered later in life by chance or following respiratory symptoms, signs of the upper gastrointestinal tract, or of the heart (e. g. foramen of Morgagni hernias and Bochdalek's hernias with a hernia sac).

1) Typical and important cause of a respiratory distress syndrome in the first 24 hours of a neonate.
2) Significant pre- and postnatal mortality.
3) Depending on the indication for and the modalities of treatment in some of the surviving children longterm patients with a chronic lung disease.
4) Most of the patients have a gastroesophageal reflux which is operative in some of the children.
5) Treatment and survival restricted by lung hypoplasia with insufficient postpartal differentiation and/or by pulmonary arterial hypertension.

Unknown.

In four fifths of congenital diaphragmatic hernias the left side is involved, and up to 15 % have a hernia sac. The defect of the diaphragm which allows a communication between the abdomen and the thorax ranges from a small posterolateral hole up to a nearly total defect.
The less frequent Morgagni hernia is often bilateral, anteromedially (sternocostally) situated and contains processes of the liver, or parts of the gastrointestinal tract.

In up to 90 % a prenatal diagnosis is possible by ultrasound prior to the 24th week of gestation.
Usually, a severe respiratory distress syndrome develops immediately after birth or within 24 hours.
No breath sound can be auscultated over the left hemithorax; the physiological cardiac murmurs are heard on the right hemithorax, and the abdominal cavity is small and its surface under the thoracic level.

In up to 50 % severe associated malformations are found, and often a gastroesophageal reflux. In all congenital diaphragmatic hernias there is a nonrotation or an incomplete rotation.

One third of all patients with congenital diaphragmatic hernia die already prenatally due to associated severe malformations. In cases of congenital diaphragmatic hernias without or only with minor malformations there is a mortality of 45 to 60 %, depending on whether only the cases with treatment are counted or, in addition, the patients who die pre- or postnatally prior to operative treatment (Harrison MR et al. JAMA 271:382,1994). Also, see 'incidence'.

The differential diagnosis includes all lesions leading to a respiratory distress syndrome. Among these pathologies, the pediatric surgical causes can be divided in 5 groups with different on-going pathophysiological mechanisms. Radiologically the congenital diaphragmatic hernia resembles a cystic adenomatoid malformation, and an unilateral foramen of Morgagni hernia a mediastinal tumor or lesions with eventration of the diaphragm (congenital malformation or acquired lesion due to a paralysis of the phrenic nerve as in birth injury or postoperative).

Chest x-ray in 2 planes: Displacement of the heart shadow to the side not involved; on the involved side, instead of a normal lung, polycystic structures can be seen which are due to the herniated intestinal loops filled with air and fluid, and a distended stomach.
In the intensive care unit (=ICU): Analysis of the arterial blood gases, of the ventilatory data, and search for additional malfomations.
In Bochdalek's hernias diagnosed after the neonatal period by chance from chest x-rays or based on symptoms and signs an esophagogastroduodenogram and/or CT may be necessary.

Selected cases are operated prenatally in specialized centers with in utero closure of the defect.
In cases with a diagnosis beyond the neonatal period, transabdominal, thoracoabdominal, or thoracic closure of the defect must be performed.
In cases of respiratory distress syndrome in the first 24 hours postnatally, stabilization and prognostication of the respiration are performed at the ICU using additional procedures, such as high frequency ventilation, nitric oxyd application and extracorporeal membrane oxygenation (ECMO) to normalize the pulmonary arterial pressure, and, depending on the course, delayed surgery is performed.
One possible indication to start with surgery is a peak inspiratory pressure (PIP) less than 25 cm of water, a FiO2 of less than 0.4, and conventional ventilation without NO. Closure of the defect is performed with or without reconstructive techniques, and with consideration of nonrotation or partial rotation.
The recurrent pneumothoraces, pulmonary arterial hypertension, and possible malformations of the heart or the large vessels are treated pre- and postoperatively.

With delayed selective surgery and without ECMO, usually no chronic lung disease occurs. 2/5 of the patients successfully treated with ECMO and surgery have a chronic lung disease. In spite of the preoperative treatment at the ICU including ECMO, mortality reaches up to 47 %.