Congenital diaphragmatic hernia. A systematic analysis

Congenital diaphragmatic hernia is a condition characterized by a defect in the diaphragm that leads to protrusion of abdominal contents into the thoracic cavity interfering with normal development of the fetal lungs. The defect may range from a small aperture in the posterior muscle rim to complete absence of the diaphragm. The pathophysiology of congenital diaphragmatic hernia is a combination of lung hypoplasia and immature birth associated with persistent pulmonary hypertension of the newborn and cardiac dysfunction. Prenatal assessment of the lung-to-head ratio and the position of the liver (presence or absence of a liver lobe in the chest) by ultrasound are used to diagnose and predict outcomes. Delivery of infants with congenital diaphragmatic hernia is recommended close to term gestation. Immediate management at birth includes bowel decompression, avoidance of mask ventilation and endotracheal tube placement if required. The primary focus of management includes gentle ventilation of the lungs, hemodynamic monitoring and treatment of pulmonary hypertension, followed by preparation for surgery only after stabilization of the newborn’s condition. Although the US Food and Drug Administration do not approve inhaled nitric oxide, it is commonly used to treat persistent pulmonary hypertension of the newborn induced by congenital diaphragmatic hernia. Extracorporeal membrane oxygenation is usually considered after failure of standard resuscitative interventions in neonates with congenital diaphragmatic hernia born at ≥34 weeks of gestational age or with body weight >2 kg and no associated gross fetal anomalies. Multiple factors such as premature birth, congenital anomalies, severity of pulmonary hypertension, type of postpartum recovery, and the need for extracorporeal membrane oxygenation affect the overall survival of infants with congenital diaphragmatic hernia. Thanks to advances in the management of patients with congenital diaphragmatic hernia, overall survival has increased, reaching 70–90 %, and with the use of extracorporeal membrane oxygenation up to 50 %.