Congenital High Airway Obstruction Syndrome

Also known as: CHAOS, congenital upper airway obstruction.

What is congenital high airway obstruction syndrome?

If a fetus’s upper airway (windpipe/trachea or voice box/larynx) becomes blocked during intrauterine development, the problem is called congenital high airway obstruction syndrome, or CHAOS.

What causes congenital high airway obstruction syndrome?

CHAOS is extremely rare. The cause of this birth defect is not known.

What are the signs/ symptoms of congenital high airway obstruction syndrome?

CHAOS is a life-threatening condition. In the fetus, it presents as very large lungs filled with fluid, a flattened diaphragm, fluid in the abdomen, and signs of heart failure which may develop and cause the death of the baby in the womb or shortly after birth, depending on its severity.

What are congenital high airway obstruction syndrome care options?

During pregnancy the baby will require close monitoring and at birth a multidisciplinary team of pediatric specialists (neonatologist, pediatric surgeon and maternal-fetal specialist) may be needed to ensure the baby's ability to breath and survival.

While the baby usually survives to birth, he/she may suffer from extreme difficulties breathing and survival may depend on the partial delivery of the baby by cesarean section while still being attached to the mother by the placental cord, during which time an artificial airway is established for the baby to breath through (EXIT).

Once this is completed the baby is then fully delivered by the completion of the cesarean section.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: April 12, 2023 10:31 AM

Fetal Care Services

The Fetal Care Service team offers support to families expecting an infant with medical needs that require intervention at birth. We provide comprehensive, coordinated care from prenatal diagnosis to the transition to infant care.

Learn More