Ex-utero intrapartum therapy.

The ex-utero intrapartum therapy (EXIT) procedure was designed to secure the airway at delivery in fetuses who had undergone tracheal occlusion for severe congenital diaphragmatic hernia. The EXIT was then adapted for deliveries where the airway may be difficult to secure, such as large neck masses or congenital high airway obstruction. Subsequently, use of EXIT has been extended to fetal anomalies where resuscitation may be compromised, including large thoracic masses, severe congenital diaphragmatic hernia, or pulmonary agenesis. The key to EXIT is preservation of uteroplacental blood flow and gas exchange, using inhalational agents to provide uterine relaxation, and maintenance of uterine volume by amnioinfusion and only partial exposure of the fetus. This provides time for procedures such as laryngoscopy, bronchoscopy, vascular access, resection of neck or lung masses, or cannulation for extracorporeal membrane circulation, in order to convert an emergent crisis to a controlled situation.