Center Volume and Survival Relationship for Neonates With Congenital Diaphragmatic Hernia Treated With Extracorporeal Life Support

Abstract

OBJECTIVES: Literature is emerging regarding the role of center volume as an independent variable contributing to improved outcomes. A higher volume of index procedures may be associated with decreased morbidity and mortality. This association has not been examined for the subgroup of infants with congenital diaphragmatic hernia (CDH) receiving extracorporeal life support (ECLS). Our study aims to examine the risk-adjusted association between center volume and outcomes in CDH-ECLS neonates, hypothesizing that higher center volume confers a survival advantage. DESIGN: Multicenter, retrospective comparative study using the Extracorporeal Life Support Organization database. SETTING: One hundred twenty international pediatric centers. PATIENTS: Neonates with CDH managed with ECLS from 2000 to 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The cohort included 4,985 neonates with a mortality rate of 50.6%. For the 120 centers studied, mean center volume was 42.4 ± 34.6 CDH ECLS cases over the 20-year study period. In an adjusted model, higher ECLS volume was associated with lower odds of mortality: odds ratio (OR) 0.995 (95% CI, 0.992–0.999; p = 0.014). For an increase in one sd in volume, that is, 1.75 cases annually, the OR for mortality was lower by 16.7%. Volume was examined as a categorical exposure variable where low-volume centers (fewer than 2 cases/yr) were associated with 54% higher odds of mortality (OR, 1.54; 95% CI, 1.03–2.29) compared with high-volume centers. On-ECLS complications (mechanical, neurologic, cardiac, hematologic metabolic, and renal) were not associated with volume. The likelihood of infectious complications was higher for low- (OR, 1.90; 95% CI, 1.06–3.40) and medium-volume (OR, 1.87; 95% CI, 1.03–3.39) compared with high-volume centers. CONCLUSIONS: In this study, a survival advantage directly proportional to center volume was observed for CDH patients managed with ECLS. There was no significant difference in most complication rates. Future studies should aim to identify factors contributing to the higher mortality and morbidity observed at low-volume centers.