Survival in early- and late-term infants with congenital diaphragmatic hernia treated with extracorporeal membrane oxygenation

Abstract

Background: Congenital diaphragmatic hernia (CDH) is a malformation of the diaphragm that allows bowel to enter the thoracic cavity, resulting in pulmonary hypoplasia and pulmonary hypertension. Approximately 50% of CDH patients are treated with extracorporeal membrane oxygenation (ECMO). The optimal gestational age for delivery of term infants with CDH at high risk for requiring ECMO is not known. The goal of this study was to compare survival of infants with CDH receiving ECMO born early term (38 0/7-39 6/7 weeks' gestation) with those born late term (40 0/7-41 6/7 weeks' gestation). Changes in survival rates of term infants and the factors associated with these changes were assessed over the 25 years that ECMO has been available.

Design: Retrospective cohort study of infants with CDH treated with ECMO.

Data sources: The Extracorporeal Life Support Organization registry of patients treated at active Extracorporeal Life Support Organization centers from April 1976 through June 2001.

Analysis: Survival and clinical predictors of survival were compared between infants born early term (38 0/7-39 6/7 weeks' gestation) and infants born late term (40 0/7-41 6/7 weeks' gestation). Changes in survival rates over time and factors associated with survival were evaluated.

Results: Among full-term infants with CDH treated with ECMO, late-term compared with early-term delivery was associated with improved survival (63% vs 53%). Among full-term survivors of ECMO, late-term infants spent less time on ECMO (181 vs 197 hours) and less time in the hospital (60 vs 67 days). In multivariate analysis, greater birth weight, higher 5-minute Apgar score, higher arterial pH and PCO(2) <50 torr before ECMO, and absence of a prenatal diagnosis of CDH were associated with survival. Since the late 1980s, survival of infants with CDH requiring ECMO decreased from 63% to 52%. The decreased survival rate was associated with increased rates of prenatal diagnosis, early-term delivery, lower birth weight, longer ECMO runs, and more frequent complications on ECMO.

Conclusions: Among term infants with CDH receiving ECMO, late-term delivery compared with early-term delivery is associated with improved survival, shorter ECMO duration, shorter hospital length of stay, and fewer complications on ECMO. These data suggest that, at least for the approximately 50% of CDH patients treated with ECMO, outcomes for infants with CDH may be improved by delay of elective delivery until 40 completed weeks of gestation.