In fetuses with left-sided isolated congenital diaphragmatic hernia (LCDH), prenatal detection of severe pulmonary hypoplasia is relevant since fetal therapy can improve survival. Moderate and mild hypoplasia still carry a considerable mortality and morbidity risk, but there has been less interest in the accurate prediction of these. In this study on fetuses with moderate or mild CDH, we aimed to investigate: (1) the correlation between intra-pulmonary-artery Doppler (IPaD) findings and mortality, (2) whether adding these improves prediction of mortality based on lung size and liver herniation; and (3) whether the IPaD correlates with early neonatal morbidity.
This is a retrospective study including all consecutive fetuses assessed at the BCNatal and UZ Leuven hospitals between 2008 and 2020, with a prenatal diagnosis of isolated, non-severe-LCDH, defined by an observed/expected lung-to-head-ratio (o/e LHR) >25%, and who were expectantly managed during pregnancy followed by standardized neonatal management. An additional criterium was the availability of IPaD measurements. The primary outcome was the correlation between IPaD and mortality. Predictors included o/e LHR, liver herniation, and gestational age at birth. Secondary outcomes were the correlation between IPaD and the presence of pulmonary hypertension (PHT), need for O at discharge, and need for extracorporeal membrane oxygenation (ECMO). IPaD pulsatility-index (PI) values were converted into z-scores. Logistic regression was performed to investigate the correlations, and the best model was chosen based on the Naegelkerke R2.
Observations on 70 non-severe-LCDH cases were available. Survival to discharge rate was 54 (77%). In a logistic regression analysis, a higher IPaD-PI was associated with increased mortality [OR 3.96 (95% CI 1.62 – 9.70)], independently from the o/e LHR [0.87 (0.79 – 0.97)]. An IPaD-PI cutoff of >1.8 predicted mortality with a detection rate of 69% and specificity of 93%. Combining o/e LHR and Doppler, the detection rate was 81% at a 10 %-false-positive rate. The IPaD-PI was correlated with PHT [OR 2.20 (95% CI 1.01 – 4.59)] and O at discharge [OR 1.9 (95% CI 1.1 – 3.4)], independently of the lung size.
In fetuses with mild or moderate LCDH, the IPaD-PI correlated with mortality and morbidity, independently from lung size. A model combining o/e LHR with IPaD-PI identified four out of five cases that eventually died, despite being considered as having non-severe pulmonary hypoplasia. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.