(130) Prenatal Total Lung Volumes Predict Outcomes Among Fetuses with Congenital Genitourinary Anomalies

Congenital genitourinary (GU) anomalies are associated with oligohydramnios, pulmonary hypoplasia, and postnatal respiratory failure. Little data exists to describe the use of total lung volumes (TLV) obtained via fetal MRI to predict outcomes. We hypothesize that observed-to-expected TLV (O/E TLV) measured by fetal MRI can be used to predict postnatal respiratory morbidity as well as survival among fetuses with GU anomalies.

Study Design:

We performed a retrospective review of all fetuses diagnosed with GU anomalies managed at our institution between January 1, 2012 and July 1, 2022.  O/E TLV, as well as oligohydramnios (defined by an amniotic fluid index < 5) and anhydramnios, were correlated with postnatal outcomes. Those who elected termination or comfort care were excluded from analysis.

Results:

Twenty-eight patients met inclusion criteria. Five (18%) terminated in utero and five (18%) elected comfort care upon delivery.  Excluding this cohort, ten (44%) survived. Low O/E TLV directly correlated with need for delivery room respiratory support, need for extracorporeal membrane oxygenation (ECMO), and death (Figure). All patients with O/E TLV less than 36% died. Presence of oligohydramnios or anhydramnios only correlated with need for delivery room respiratory support.  No prenatal measurement predicted need for delivery room intubation or presence of pulmonary hypertension (Table).

Conclusion:

O/E TLV predicts need for supplemental oxygen, ECMO cannulation, and overall survival. These data suggest that O/E TLV, rather than amniotic fluid volume indices, may be a useful tool to prognosticate and counsel parents on the outcomes of pulmonary hypoplasia in the setting of GU anomalies.