OBJECTIVES: Reports on volume–outcome relationships have suggested that surgical and interventional procedures should be centralized. However, because pediatric surgery is rare and complex, there is limited evidence in this field. We investigated the situation and hospital-level volume–outcome relationship for neonatal surgery in Japan.

METHODS: We utilized data recorded in the National Clinical Database (NCD) pediatric surgical registry (January 2015–December 2020). Hospitals were categorized as low-volume (>0 to <10), middle-volume (≥10 to <36), and high-volume (≥36) based on the mean annual number of neonatal surgeries. We compared the incidences of periprocedural outcomes among six major procedures esophageal atresia, congenital diaphragmatic hernia, omphalocele, gastroschisis, intestinal atresia, and duodenal atresia by surgical volume. The outcomes included death at hospital discharge, any postoperative complications within 30 days, postoperative surgical complications (wound dehiscence, anastomotic leakage, reoperation, readmission) within 30 days, and operation time. The hospital volume–outcome associations were adjusted for surgery type, gestational age, preoperative cardiac risk, chromosomal abnormality, and Apgar score at 5 minutes.

RESULTS: Of 738 registered hospitals, 154, 76, and 12 were categorized as low-, middle-, and high-volume hospitals, respectively; 496 performed no neonatal surgery. The frequency of any postoperative complications was lower at high-volume (252/1075 [23.5%]) than at low-volume (230/770 [29.9%]; adjusted odds ratio [aOR] 1.46, 95% confidence interval [CI] 1.16–1.83) and middle-volume (622/2219 [28.0%]; aOR 1.31, 95% CI 1.09–1.58) hospitals. Average operation time was 15.2 (95% CI 9.08–21.4) and 6.68 (95% CI 1.85–11.5) minutes longer at low- and middle-volume hospitals than at high-volume hospitals, respectively. We found no significant differences in mortality or individual postoperative surgical complications.

CONCLUSIONS: The incidence of any postoperative complications after neonatal surgery was lower at high-volume hospitals where operation times were also shorter. Centralizing neonatal surgical facilities may improve the quality of pediatric surgery in Japan.