EXIT to airway: série de casos clínicos e revisão sistemática de achados de imagem preditores de via aérea difícil

Abstract

Introduction – Airway obstruction at birth can be fatal, requiring interventions such as the Ex Utero Intrapartum Treatment (EXIT) to ensure fetal oxygenation while securing the airway. Despite advances in diagnosis and treatment, well-established guidelines for its indication are still lacking due to the rarity of the condition. This study reviewed EXIT cases at the Hospital das Clínicas da UFMG, between 2020–2024, and conducted a systematic review to investigate predictive signs of difficult airway. Prenatal imaging findings, such as polyhydramnios, cervical teratoma, micrognathia, and signs associated with congenital high airway obstruction syndrome (CHAOS), were analyzed and correlated with neonatal airway management characteristics. Results – Diaphragmatic flattening or inversion, enlarged and/or hyperechoic lungs, and tracheal fluid distension were the strongest predictors of difficult airway, with 100% incidence (p < 0.001). The presence of polyhydramnios in fetuses with cervical teratoma increased the likelihood of difficult airway by 3.8 times (95% CI: 1.2–11.8). Polyhydramnios, diaphragmatic flattening/inversion, and enlarged/hyperechoic lungs were associated with a placental circulation duration during EXIT ≥ 10 minutes, while cervical teratoma and solid cervical masses were linked to durations ≥ 20 minutes. Conclusion – Ultrasound and MRI findings, such as diaphragmatic flattening, hyperechoic lungs, and tracheal distension, are strongly associated with difficult airway in fetuses undergoing EXIT. Polyhydramnios and cervical teratomas were also relevant. Future studies with greater methodological rigor are essential to validate these findings and optimize case selection for EXIT.