Balloon removal after fetoscopic endoluminal tracheal occlusion for congenital diaphragmatic hernia

Isolated congenital diaphragmatic hernia defect allows viscera to herniate into the chest, competing for space with the developing lungs. At birth, pulmonary hypoplasia leads to respiratory insufficiency and persistent pulmonary hypertension that is lethal in up to 30% of patients. Antenatal measurement of lung size and liver herniation can predict survival after birth. Prenatal intervention aims at stimulating lung development, clinically achieved by percutaneous fetal endoscopic tracheal occlusion under local anesthesia. This in utero treatment requires a second intervention to reestablish the airway, either before birth or at delivery.

To describe our experience with in utero endotracheal balloon removal.

This is a retrospective analysis of prospectively collected data on consecutive patients with congenital diaphragmatic hernia treated in utero by fetal endoscopic tracheal occlusion from 3 centers. Maternal and pregnancy-associated variables were retrieved. Balloon removal attempts were categorized as elective or emergency and by technique (in utero: ultrasound-guided puncture; fetoscopy; ex utero: on placental circulation or postnatal tracheoscopy).

We performed 351 balloon insertions during a 144-month period. In 9 cases removal was attempted outside fetal endoscopic tracheal occlusion centers, 3 of which were deemed impossible and led to neonatal death. We attempted 302 in-house balloon removals in 292 fetuses (217 elective [71.8%], 85 emergency [28.2%]) at 33.4 ± 0.1 weeks (range: 28.9-37.1), with a mean interval to delivery of 16.6 ± 0.8 days (0-85). Primary attempt was by fetoscopy in 196 (67.1%), by ultrasound-guided puncture in 62 (21.2%), by tracheoscopy on placental circulation in 30 (10.3%), and postnatal tracheoscopy in 4 cases (1.4%); a second attempt was required in 10 (3.4%) cases. Each center had different preferences for primary technique selection. In elective removals, we found no differences in the interval to delivery between fetoscopic and ultrasound-guided puncture removals. Difficulties during fetoscopic removal led to the development of a stylet to puncture the balloon, leading to shorter operating time and easier reestablishment of airways.

In these fetal treatment centers, the balloon could always be removed successfully. In 90% this was in utero, with the use of fetoscopy preferred over ultrasound-guided puncture. Ex utero removal was a fall-back procedure. In utero removal does not seem to precipitate immediate membrane rupture, labor, or delivery, although the design of the study did not allow for a formal conclusion. For fetoscopic removals, the introduction of a stylet facilitated retrieval. Successful removal may rely on a permanently prepared team with expertise in all possible techniques.