Does extracorporeal membrane oxygenation improve survival in neonates withcongenital diaphragmatic hernia?

Background/Purpose: The benefit of extracorporeal membrane oxygenation (ECM O) in improving survival of neonates with congenital diaphragmatic hernia ( CDH) has never been clearly demonstrated. This may be due to comparisons ma de between treatment groups of unequal illness severity and the low statist ical power of analyses from previous studies. The authors analyzed the data from the multicenter CDH registry to determine if ECMO improves survival i n CDH neonates with a high risk of mortality. Methods: A total of 730 neonates were enrolled in the CDH Registry from Jan uary 1995 to November 1997. Of these, 632 neonates had a complete data set and were eligible for ECMO by the weight criterion of greater than 2.0 kg. Multivariate logistic regression analysis was used to assess mortality risk for each neonate based on previously validated independent predictors of s urvival: birth weight and 5-minute Apgar. Five quintile groups were defined based on increasing predictive mortality risk. Multivariate logistic regre ssion and chi(2) analyses with birth weight, Apgar score at 5 minutes, and predictive mortality risk as covariates were then performed to assess survi val benefit of ECMO compared with conventional therapy alone. Patient survi val rate was defined as survival to discharge from hospital. Results: When analyzing all 632 neonates, ECMO neonates (n = 289) had a dec idedly lower survival rate (52.9% v 77.3%, P < .001) than non-ECMO neonates (n = 343) without standardizing for the degree of illness. However, when t aking into account the patients' predictive mortality risk, ECMO was associ ated with improved survival in the neonates with mortality risk greater tha n or equal to 80% (P < .05), Furthermore, ECMO was shown to be a positive i ndependent predictor of survival when accounting for the covariates of birt h weight, 5-minute Apgar, and mortality risk (P < .05). Conclusions: ECMO significantly improves survival rates for those CDH neona tes with a predictive mortality risk greater than or equal to 80%. Generall y, the more critically ill the patient with CDH, the more marked the surviv al benefit obtained. Copyright (C) 1999 by W.B. Saunders Company.