Effectiveness of prenatal predictors for congenital diaphragmatic hernia on survival to discharge and extracorporeal membrane oxygenation requirement: a retrospective cohort study

Abstract Introduction Congenital diaphragmatic hernia (CDH) is associated with high mortality and morbidity. Antenatal counselling enables parents to prepare for the postnatal outcomes and relies on effective prognostic tools. Ultrasound (USS) predictors including observed/expected lung head ratio (o/e LHR) and liver position, are used independently, or combined into severity classifications. The aim was to evaluate the association between USS predictors, and severity classifications with survival to discharge and extracorporeal membrane oxygenation (ECMO) requirement in prenatally diagnosed CDH at Birmingham Women’s and Children’s Hospital (BWC). Methods CDH patients from BWC with dates of birth between 1st December 2013–1st December 2023 were retrospectively collected. Study inclusion required o/e LHR measurement between 22- and 32-weeks gestational age (GA.) Comparisons between groups was assessed by Fisher exact test and Mann-Whitney U test. Logistic regression was performed to determine prognostic ability, with area under curve (AUC) calculated. Results 91 eligible patients were identified, which included 82 left-sided, and 9 right-sided CDH. Overall, 55% survived to discharge and 13% required ECMO. In the left CDH cohort, 57% of infants survived to discharge, and 15% required ECMO. O/e LHR, liver position and the combined predictive model including o/e LHR and liver position were predictive of survival to discharge with good prognostic ability (AUC 0.769, AUC 0.703, and AUC 0.823, respectively). O/e LHR, liver position, and the combined predictive model were not predictive of ECMO requirement. In the right CDH patients, 33% survived to discharge, O/e LHR and liver position were not predictive of survival to discharge. Conclusion O/e LHR, liver position and the combination of these predictors, predicted survival to discharge in prenatally diagnosed left CDH with the combined model, the most predictive particularly in the isolated left CDH sub-group. Further analysis into effective predictors for ECMO requirement, and for right and complex left CDH is required.