Prenatal diagnosis of congenital high airway obstruction syndrome: our experience from a tertiary care center

Congenital high airway obstruction syndrome (CHAOS) is an extremely rare and life-threatening condition. It occurs due to obstruction in fetal respiratory tract and is characterized by typical ultrasonographic findings. Risk of recurrence is low, so antenatal diagnosis can help in counselling regarding risk of recurrence. A retrospective record review of all cases referred to our institution for antenatal ultrasound over a period of 5 years from January, 2014 to December, 2018 was done. Cases diagnosed as CHAOS were reviewed in detail regarding the radiological findings, information regarding delivery, fetal karyotype and postnatal/ fetal examination. Between the period of 2014 to 2018 three fetuses with CHAOS were identified. All of them had characteristic radiological features. Two of them were associated with hydrops and one fetus had oligohydramnios. All the pregnancies were terminated after antenatal diagnosis. Amniocentesis was done in 2 out of 3 cases and fetal karyotype was found to be normal. Fetal autopsy was done in one case and site of upper airway obstruction was identified. Confirmation of diagnosis by antenatal ultrasound and if possible, by post-mortem examination is essential for providing estimation of risk of recurrence to the family and genetic counselling.

Prenatal MRI assessment of fetal congenital high airway obstruction syndrome / 中华放射学杂志

Objective To investigate the manifestation and diagnostic value of the congenital high airway obstruction syndrome(CHAOS)in fetal MRI.Methods Prenatal fetal MRI images were reviewed in 9 fetuses from February 2014 to February 2017 which were screening by ultrasound and underwent MR examination within 2 days. Scanning sequence included HASTE, True-FISP, T2WI、T1WI and DWI sequence. If found suspicious airway obstruction, the fetus will be add the sequence in coronal planes. Prenatal US and MR imaging findings were compared with specimen MR imaging and pathological results. Results All the fetuses viewed demonstrated the following MRI findings:bilateral lung volume increased, increased lung signal on T2WI, dilated airway below the lever of obstruction, flattened or inverted hemidiaphragms,centrally positioned and compressed heart.Ascites and anasarca could be find in 8 cases. Prenatal MRI identified the level of obstruction was 5 cases in laryngeal and 4 cases in tracheal.Four cases of laryngeal obstruction and 3 cases of tracheal obstruction were finally confirmed by autopsy.One case died in intrauterine,and the other 1 case was lost to follow-up.Conclusion MRI shows a special performance in fetals with CHAOS,accurately identifies the level of airway obstruction,and can provide help for perinatal management.

Exit: tratamiento exútero intraparto: reporte de caso y revisión de la literatura / Exit: ex-utero intrapartum treatment: a case report and literature review

Introducción y objetivo: la técnica Tratamiento exútero intraparto (EXIT) permite el aseguramiento de la vía aérea fetal mientras se mantiene el soporte uteroplacentario íntegro. El objetivo de reportar este caso es describir el procedimiento y hacer una revisión de la literatura mundial respecto a consideraciones anestésicas y complicaciones asociadas. Materiales y métodos: presentamos el caso de una neonato femenina de 39 semanas de gestación que nace mediante la técnica Tratamiento exútero intraparto (EXIT) debido a una potencial obstrucción de la vía aérea detectada en una ecografía de tercer trimestre. Se realizó una búsqueda sistemática usando las palabras clave: Tratamiento exútero intraparto (EXIT), masas cervicales congénitas y CHAOS en las bases de datos Medline via Pub Med, Ovid, y la base latinoamericana SciELO. Resultados: se encontraron un total de 183 artículos, de los cuales 76 estaban relacionados directamente con el tema, de estos se seleccionaron 8 reportes de caso, 2 series de casos y 14 revisiones del tema. Conclusiones: la estrategia EXIT prueba ser una herramienta útil en el adecuado manejo de los neo-natos con obstrucciones congénitas de la vía aérea.

Introduction and objective: The EXIT procedure (ex-utero intrapartum treatment) is aimed at securing the fetal high airway whilst maintaining integral uteroplacentary circulation. The purpose of reporting this case was to describe the procedure and review the worldwide literature regarding anesthetic considerations and associated complications. Materials and methods: The case of a 39-week gestation female neonate is presented; she was born at the Clínica del Country (a private highlevel healthcare general hospital located in Bogota, Colombia) by the ex-utero intrapartum treatment (EXIT) technique due to a potential obstruction of the airway detected during third-trimester echography. A systematic search was made of Medline databases via PubMed, Ovid, and the SciELO Latin-American database using the following key words: EXIT, ex-utero intrapartum treatment, congenital cervical mass, CHAOS. Results: 183 articles were found, of which 76 were directly related to the topic; 8 case reports, 2 case series and 14 reviews of the topic were selected. Conclusion: The EXIT strategy has proved to be a useful tool in the suitable management of neonates suffering congenital obstruction of the airway.

Tratamiento extrauterino intraparto: manejo del recién nacido con síndrome de obstrucción congénita de la vía aérea superior: informe de un caso / Ex utero intrapartum treatment: management of neonatal congenital high airway obstruction syndrome: case report

En años recientes, el tratamiento extrauterino intraparto, que consiste en la intubación fetal extrauterina previa al nacimiento, ha adquirido relevancia en la reducción de la morbimortalidad de neonatos afectados por el síndrome de obstrucción congénita de la vía aérea superior. Caso clínico. Presentamos una madre con un feto de 22 semanas de gestación y diagnóstico de estenosis de la vía aérea, que anticipaba déficit ventilatorio fetal extraparto y derivó en la aplicación del tratamiento extrauterino intraparto para garantizar el intercambio gaseoso fetal en el momento del nacimiento. Conclusiones. La práctica oportuna del procedimiento extrauterino intraparto logró en este caso, mediante el control de los factores maternos y fetales que pudieran afectar la circulación feto-placentaria, el nacimiento de un niño cuya evolución inmediata y a largo plazo fue exitosa con desarrollo deuna vida normal.

In recent years, the ex utero intrapartum treatment (EXIT), that involves extrauterine fetal intubation prior to delivery, has become relevant for the reduction in morbidity and mortality of neonates affected by congenital high airway obstructionsyndrome (CHAOS). Clinical case. We report the case of the mother of an unborn child at pregnancy week 22, who was diagnosed a congenitalpulmonary malformation that precluded intrapartum fetal circulatory deficit and resulted in the conduction of an EXITtechnique, with the aim of ensuring fetal blood gas exchange at the time of delivery. Conclusions. A timely practice of the EXIT technique resulted, by monitoring both maternal and fetal factors that might affect fetoplacental circulation, in the birth of a child whoseimmediate and long-term outcomes were successful allowing the child live a normal life.

Prenatal MRI Findings of Fetuses with Congenital High Airway Obstruction Sequence

OBJECTIVE: To define the MRI findings of congenital high airway obstruction sequence (CHAOS) in a series of fetuses. MATERIALS AND METHODS: Prenatal fetal MR images were reviewed in seven fetuses with CHAOS at 21 to 27 weeks of gestation. The MRI findings were reviewed. The MRI parameters evaluated included the appearance of the lungs and diaphragm, presence or absence of hydrops, amount of amniotic fluid, airway appearance, predicted level of airway obstruction, and any additional findings or suspected genetic syndromes. RESULTS: All the fetuses viewed (7 of 7) demonstrated the following MRI findings: dilated airway below the level of obstruction, increased lung signal, markedly increased lung volumes with flattened or inverted hemidiaphragms, massive ascites, centrally positioned and compressed heart, as well as placentomegaly. Other frequent findings were anasarca (6 of 7) and polyhydramnios (3 of 7). MRI identified the level of obstruction as laryngeal in five cases and tracheal in two cases. In four of the patients, surgery or autopsy confirmed the MRI predicted level of obstruction. Associated abnormalities were found in 4 of 7 (genetic syndromes in 2). Postnatal radiography (n = 3) showed markedly hyperinflated lungs with inverted or flattened hemidiaphragms, strandy perihilar opacities, pneumothoraces and tracheotomy. Two fetuses were terminated and one fetus demised in utero. Four fetuses were delivered via ex utero intrapartum treatment procedure. CONCLUSION: MRI shows a consistent pattern of abnormalities in fetuses with CHAOS, accurately identifies the level of airway obstruction, and helps differentiate from other lung abnormalities such as bilateral congenital pulmonary airway malformation by demonstrating an abnormally dilated airway distal to the obstruction.