Neighborhood Opportunity, Hospital Volume, and Pediatric Postoperative Mortality.

Importance: Sociodemographic disparities in pediatric perioperative care are often associated with residential segregation, referral patterns, and the regionalization of quaternary centers, which can concentrate patients from disadvantaged neighborhoods in low-volume hospitals. Although neighborhood conditions are increasingly recognized as critical to child health, their interaction with hospital volume and postoperative mortality remains unclear. Objectives: To assess the association of neighborhood opportunity with pediatric postoperative mortality, and whether this association is modified by hospital volume. Design, Setting, and Participants: This retrospective cohort study used the multicenter administrative Pediatric Health Information System (PHIS) database from January 1, 2012, to September 30, 2024. The study comprised patient encounters among children younger than 18 years who underwent inpatient surgical procedures at a PHIS-reporting hospital. Exposure: Neighborhood opportunity, as measured by the Child Opportunity Index 3.0, modified by hospital volume. Main Outcomes and Measures: Postoperative in-hospital mortality. Results: Of 996 865 inpatient surgical encounters among 821 865 children (mean [SD] age, 7.2 [5.9] years), 55.7% of encounters were among boys, 16.0% were among children who resided in neighborhoods of very high opportunity, 17.9% in neighborhoods of high opportunity, 18.0% in neighborhoods of moderate opportunity, 21.1% in neighborhoods of low opportunity, and 27.0% in neighborhoods of very low opportunity. In addition, 71.8% of patients were treated at high-volume centers, and 28.2% at low-volume centers. The in-hospital postoperative mortality rate was 0.9%, with higher rates observed among children from lower opportunity areas. Compared with children from very high opportunity neighborhoods, increased mortality risk was associated with decreasing neighborhood opportunity, reaching a 27% higher risk in very low opportunity areas (adjusted risk ratio [ARR], 1.27; 95% CI, 1.18-1.38; P < .001). Mortality rates also varied by hospital volume, with rates of 0.88% at high-volume centers and 0.92% at low-volume centers. Care at low-volume centers was associated with an 11% higher risk of in-hospital mortality compared with high-volume centers (ARR, 1.11; 95% CI, 1.06-1.16; P < .001); however, hospital volume did not modify the association between neighborhood opportunity and mortality. Conclusions and Relevance: In this cohort study, higher neighborhood opportunity was associated with lower risk of in-hospital postoperative mortality among pediatric patients. Although care at high-volume hospitals is typically associated with improved outcomes, this association was not observed for children from disadvantaged neighborhoods. These findings suggest that, beyond hospital-level interventions, addressing area-level social drivers of health may be essential to improving surgical outcomes in pediatric populations.