A population-based study of congenital diaphragmatic hernia: Impact of associated anomalies and preoperative blood gases on survival

Background/Purpose: Although neonatal care has improved over the past 20 ye ars, mortality rate with congenital diaphragmatic hernia (CDH) remains 50% to 60%, possibly reflecting differences in management or selection biases. The authors determined the incidence, outcome, effect of coexisting anomali es, and prognostic indicators for neonates with CDH in a single inborn popu lation alder than 13 years. Methods: Forty-three neonates with CDH, those symptomatic within the first 6 hours of life, were identified using a validated neonatal database and di agnosis coding data from medical records among 180,643 live inborn neonates delivered at Parkland Memorial Hospital between 1983 and 1995. Charts were reviewed for prenatal history, demographic variables, presence of coexisti ng malformations, preoperative arterial blood gases, surgical findings, and outcome. Survival to hospital discharge was the primary outcome variable. Results:The incidence of CDH was 1 in 4,200 live births; overall survival r ate was 51%. Thirty-two (74%) neonates underwent surgical repair, often at less than 8 hours of life; postoperative mortality rate was 31%. Eighteen ( 42%) had coexisting major anomalies or chromosomal abnormalities. Eighty pe rcent of neonates with isolated CDH survived, whereas 89% with CDH and asso ciated defects died. Nonsurvivors had lower birth weights and Apgar scores, were more acidotic, and had more severe respiratory compromise, When best preoperative pH was greater than or equal to 7.25 or PaCO2 less than or equ al to 50 mm Hg, 80% of neonates survived. Conclusion: In this inborn population-based review of neonatal CDH between 1983 and 1995, the best predictors of survival were the presence or absence of other anomalies and the best preoperative PaCO2 and pH. Copyright (C) 1 999 by W.B. Saunders Company.