Congenital high airway obstruction syndrome.

Congenital high airway obstruction syndrome (CHAOS) is a very rare fetal malformation caused by obstruction of fetal airway because of laryngeal or tracheal atresia, subglottic stenosis, laryngeal cyst or laryngeal web. The prenatal diagnosis is inferred from secondary changes such as enlarged, hyperechogenic lungs, ascites and/or hydrops, flattened or everted diaphragms, dilated distal airways and mediastinal compression. There are only few cases of long-term survival described in literature. We present the case of fetus with such secondary changes diagnosed during routine ultrasound evaluation in 20 weeks' gestation. There were no other abnormalities and the kariotype was normal. In 26 weeks' gestation fetal hydrops appeared and subsequent polyhydramnios occurred in 28 weeks' gestation. The patient was planned for EXIT procedure during labor in experienced in CHAOS cases center. In 29 weeks' gestation the premature rupture of membranes and regular uterine contractions occurred and we've performed cesarean section. A multidisciplinary team of neonatologists, laryngologists and pediatric surgeons made their efforts to save the newborn, but there was complete laryngeal atresia and tracheal agenesia and immediate tracheostomy was impossible. The most important about CHAOS are early diagnosis, detailed fetal assessment and an adequate postnatal intervention for establishing fetal airways.