Development of an age-adapted simplified acute physiology score II using first-24-hour variables in pediatric patients with congenital diaphragmatic hernia: the CDH-SAPS.

Accurate early risk stratification in patients with congenital diaphragmatic hernia (CDH) remains challenging, as existing pediatric mortality prediction scores may not adequately reflect CDH-related pathophysiology. The main objective was to develop an early risk stratification model by adaptation of the Simplified Acute Physiology Score II (SAPS II) for mortality and extracorporeal membrane oxygenation (ECMO) requirement prediction in patients with CDH. This retrospective single-center study included pediatric patients with CDH treated at a tertiary neonatal and pediatric intensive care unit between January 2000 and December 2025. An expanded CDH-SAPS was developed by age adaptation and CDH-specific modification of SAPS II variables, followed by simplification for bedside applicability, resulting in CDH-SAPS. Both scores integrate early clinical and laboratory parameters during the first 4 h after admission complemented by 3 variables reflecting the need for major therapeutic interventions during the first 24 h. Predictive performance was compared with the Pediatric Index of Mortality 3 (PIM3) and the Score for Neonatal Acute Physiology II (SNAP-II), with the ICU mortality as primary, and ECMO requirement as secondary outcome. Among 95 included patients, the ICU mortality was 12% (n = 11), and 26% (n = 25) required ECMO support. Similar to the expanded CDH-SAPS, the CDH-SAPS demonstrated excellent discriminative ability for mortality prediction (AUROC, 0.925; 95% CI, 0.867-0.982; p < 0.001), with good agreement between predicted and observed outcomes. For ECMO requirement prediction CDH-SAPS showed moderate to good performance (AUROC, 0.789; 95% CI, 0.691-0.887; p < 0.001).

conclusionThe CDH-SAPS demonstrates excellent discrimination for the ICU mortality and reliable ECMO requirement prediction in patients with CDH, supporting its use as a practical bedside tool for early clinical decision-making. WHAT IS KNOWN: • Early risk stratification in congenital diaphragmatic hernia remains challenging because general pediatric illness severity scores may inadequately reflect disease-specific risks. WHAT IS NEW: • CDH-SAPS is a disease-specific, simplified bedside score that accurately predicts mortality and ECMO requirement, and supports serial assessment of disease progression.