Fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia: systematic review and meta-analysis

It is debated whether fetal endoscopic tracheal occlusion (FETO) is beneficial to fetuses with congenital diaphragmatic hernia (CDH) and whether FETO has different effects in moderate and severe CDH. We conducted a systematic review and meta-analysis including the latest evidence to assess the overall effects of FETO on clinical outcomes of CDH.

We searched PubMed, EMBASE, The Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database and Wanfang Database to retrieve eligible studies published before 8 September 2022. No language or study design restrictions were applied. Studies were included if CDH fetuses underwent FETO surgery and were compared with a cohort that underwent expectant management, with at least one outcome reported. The primary outcomes were mortality at 1, 6 and 12 months after birth, rates of pulmonary hypertension, use of extracorporeal membrane oxygenation (ECMO) and prematurity. Meta-analysis was conducted to obtain pooled odds ratios (ORs) and mean differences. The quality of included studies and pooled evidence was also assessed.

A total of 1187 CDH fetuses from 20 studies were included in the quantitative synthesis. FETO significantly reduced 1-month (OR, 0.56 (95% CI, 0.34-0.93); P = 0.02, number needed to treat (NNT) = 7.67) and 6-month (OR, 0.34 (95% CI, 0.18-0.65); P = 0.0009, NNT = 5.26) CDH mortality (moderate/low quality of evidence). Subgroup analysis suggested that the effects of FETO on the rates of pulmonary hypertension and ECMO usage were significant in severe CDH (low/moderate quality of evidence) but not in moderate CDH (low/very low quality of evidence). FETO was also associated with an increased risk of preterm prelabor rupture of membranes before 37 weeks' gestation (OR, 4.94 (95% CI, 2.25-10.88); P < 0.0001, number needed to harm (NNH) = 3.13) and preterm birth before 37 weeks (OR, 5.24 (95% CI, 3.33-8.23); P < 0.00001, NNH = 2.79) (high/moderate quality of evidence). However, FETO was not associated with severe complications, such as preterm birth before 32 weeks, placental abruption or chorioamnionitis (very low/low quality of evidence).

FETO is associated with a reduction in mortality, rate of pulmonary hypertension and ECMO usage in severe CDH, while it reduces only the risk of mortality in moderate CDH. Although FETO increases the risk of late prematurity, it does not result in extreme prematurity. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.