Congenital High Airway Obstruction Syndrome / CHAOS is a condition in which the fetus has:

  • Massively enlarged lungs
  • A flattened diaphragm
  • A dilated tracheobronchial tree
  • Fluid in the abdomen
  • Other signs of in utero heart failure (non-immune hydrops) due to complete or nearly complete obstruction of the fetal airway