Tracheal ballooning in congenital diaphragmatic hernia and tracheomalacia

Abstract

A baby diagnosed antenatally at 20 weeks gestation with left congenital diaphragmatic hernia (CDH) had balloon occlusion of his trachea in-utero at 25 weeks gestation which was removed at 35 weeks. The delivery was induced at 37 weeks because of premature rupture of membranes from 26 weeks. He was born in good condition and had repair of his left CDH on day 2 of life. Intraoperatively noted to have left diaphragmatic agenesis and required large patch to close the defect. Postoperative was difficult to wean from positive pressure ventilation. He had bronchoscopy and bronchogram which showed dilated and malacic lower trachea which ballooned with application of significant end expiratory pressure, and collapsed on expiration. He was referred to the tracheal unit where a custom made absorbable tracheal stent was inserted at 4 weeks of age. He was then gradually weaned off ventilator and discharged to ward. Following this he has had multiple emergency admissions to intensive care with sudden respiratory distress needing invasive ventilation. On one such admission, he was noted to have tracheal bleeding presumed to be caused by stent eroding into the tracheal mucosa which settled with positive pressure ventilation. A follow-up bronchoscopy at 10 weeks of age showed granuloma at the end of the stent just above the carina blocking 50% of the lumen and needing balloon dilatation. He continues to be on non-invasive ventilation and weaning gradually. Congenital diaphragmatic hernia has traditionally been associated with very high mortality rates. Most infants died of pulmonary hypoplasia and severe pulmonary hypertension. With different postnatal treatment strategies for CDH, survival improved dramatically from less than 20% several decades ago to more than 70% today. Fetal intervention has evolved as well, to a minimally invasive approach that involves a single endoscopic port and occlusion of the fetal trachea. Recent studies have shown that while this has considerably decreased the morbidity and fetal mortality of the in utero procedure, its results do not exceed the overall results of contemporary postnatal treatment however there might be a role in specific subgroup of fetuses with severe CDH and poor chances of survival.