Fetal lung-head ratio is not related to outcome for antenatal diagnosed congenital diaphragmatic hernia

We asked if fetal lung-to-head ratio (LHR) of 1.0 or lower or liver herniation had a statistical effect on survival or need for extracorporeal membrane oxygenation (ECMO), compared with LHR above 1.0 in patients with congenital diaphragmatic hernia (CDH).

Antenatal records of all patients diagnosed with CDH from January of 2002 to June of 2005 were examined. Inclusion criteria were isolated left-sided CDH and absence of significant cardiac or other anomalies/syndromes, treated solely at this institution. Lung-to-head ratio values were compared based on the value currently proposed for fetal intervention: LHR of 1.0 or lower vs LHR above 1.0. Outcome was assessed as survival (discharge to home) or need for ECMO.

Twenty-eight patients met inclusion criteria. Overall survival was 86% (24/28). Postnatal survival in fetuses with LHR of 1.0 or lower (8/11) was not statistically different from LHR above 1.0 (16/17) (73% vs 94%, P = .114). The need for ECMO in the group with LHR of 1.0 or lower (3/11) was not significantly different from those with LHR above 1.0 (1/17) (27% vs 6%, P = .114). Herniation of the fetal liver into the chest did not affect survival or need for ECMO (P = .228).

Neither LHR of 1.0 or lower nor liver herniation identified a risk factor significant enough to warrant fetal intervention. Multicenter studies may be more appropriate to investigate this clinical problem.