Tracheal side effects following fetal endoscopic tracheal occlusion for severe congenital diaphragmatic hernia

Excerpt

Despite optimal neonatal care and even in large referral centres, between 20% and 30% of neonates with isolated congenital diaphragmatic hernia (CDH) will not survive [1]. The leading causes of death remain in essence pulmonary hypoplasia and persistent pulmonary hypertension (PPHT). Prenatal medical imaging methods are used to predict individual outcome, which provides parents with prenatal options. For those with a predicted poor outcome this might include prenatal intervention, which aims to improve lung development rather than repairing the anatomical defect. Early attempts by prenatal surgical repair of the defect were abandoned as they required access by hysterotomy and because reducing liver herniation compromises the fetal circulation [2]. Tracheal occlusion (TO) prevents egress of lung liquid produced by the airway epithelium, hence induces tissue stretch, which acts as a signal for lung growth [3, 4]. Clinically TO was initially performed using extra-luminal clips with reversal during an ex-utero intrapartum tracheoplasty procedure [5]. Subsequently an endoluminal balloon was used, which allows easier reversal in utero, that itself triggers lung maturation according to experimental evidence [5‐7]. Invasiveness was further reduced by using a completely percutaneous approach, small diameter instruments with a move towards regional or local anaesthesia. Up to 2008 the FETO consortium performed more than 200 percutaneous fetoscopic endoluminal TOs (FETO) [8]. Survival rate is twice as high as predicted, the latter based on lung size measurements in case of left-sided CDH [9]. Obviously this data is based on external controls and the procedure should be considered as investigational whilst a trial has not confirmed these early findings [10]. …