Objective. Reported survival in congenital diaphragmatic hernia (CDH) fails to allow for case selection bias. This study reports the incidence of CDH in a geographically defined population over 11 years and assesses the effect of new therapies (high-frequency oscillatory ventilation, extracorporeal membrane oxygenation, inhaled nitric oxide, and delayed surgery) on survival when case selection is avoided.
Methods. A retrospective review of cases from a regional case registry, the Northern Region Congenital Anomaly Survey, was conducted.
Results. A total of 185 cases were identified. Mortality was 62% and did not vary significantly during the study period. Mortality was unaffected by the introduction of new therapies. There was a significant inverse correlation between the rate of elective termination and survival of live borns. The presence of an additional anomaly increased mortality to 79%.
Conclusions. The mortality of CDH when complete case ascertainment is achieved is unaffected by new therapies. The survival rate is principally determined by the rate of antenatal termination and the incidence of associated anomalies. Reports of improved survival of CDH should be interpreted with caution, as variations in outcome are more likely to be explained by case selection artifact.