Congenital high airways obstruction syndrome (CHAOS): report of two cases

Objective

Congenital high airways obstruction syndrome (CHAOS) is usually caused by complete or partial high airway obstruction as a result of atresia and stenosis of the larynx and trachea. Bilateral enlarged hyperechoic lungs, dilated airways, flattened or inverted diaphragms are observed at prenatal sonoghrapy. Increased intrathoracic pressure decreases venous return. The ascites, plasentomegaly and hidrops fetalis occurs with fetal heart failure. If it hasn’t been diagnosed at intra uterine life, the fetus usually couldn’t survive or die soon after labor. Acute respiratory distress as a result of difficult intubation and the presence of a point at direct laryngoscopy which allowing a narrow passage are the milestones of postnatal diagnosis in CHAOS. In this text, our aim is reporting of two cases, which was diagnosed at our hospital as CHAOS that could have been seen at 1/50000 birth.

Case1

24 years old, whom has had 17 weeks gestation, was referred to our clinic due to fetal hidrops. Obstetric ultrasound revealed bilateral hyperechoic lungs, dilated airways, inverted diaphragm and ascites. Increased in the fetal kidney size was observed. Mortality rate of the disease has been told to parents and the option of termination has offered. Parents have chosen to continue the pregnancy and ongoing weeks hidrops of fetus was obviously increased.

Case 2

19 years old, 14 weeks 5 days gestation, was referred to our clinic due to fetal ascites. In our clinic, we observed bilateral hyperechoic and enlarged lungs, inverted diaphragm and ascites. Tricuspid valve regurgitation and bilateral club foot were the other findings. Parents have chosen pregnancy termination option because of the poor prognosis of CHAOS.

Conclusion

At the early period of pregnancy, in the presence of bilateral hyperechoic and enlarged lungs, inverted diaphragm and ascites, CHAOS should be kept in mind.

Keywords

Congenital high airways obstruction syndrome, case

	File/Dsecription
	Figure 1 CHAOS, hyperechoic lungs
	Figure 2 CHAOS, inverted diyaphragm and fetal ascites
	Figure 3 CHAOS, hyperechoic lungs and inverted diyaphragm