Importance: There has been a significant expansion in the number of low-level and midlevel neonatal intensive care units (NICUs) in recent decades. Infants with necrotizing enterocolitis represent a high-risk subgroup of the very low-birth-weight (VLBW) (<1500 g) population that would benefit from focused regionalization.
Objectives: To describe the current trend toward deregionalization and to test the hypothesis that infants with necrotizing enterocolitis represent a particularly high-risk subgroup of the VLBW population that would benefit from early identification, increased intensity of early management, and possible targeted triage to tertiary hospitals.
Design, setting, and participants: A retrospective cohort study was conducted of NICUs in California. We used data collected by the California Perinatal Quality Care Collaborative from 2005 to 2011 to assess mortality rates among a population-based sample of 30 566 VLBW infants, 1879 with necrotizing enterocolitis, according to the level of care and VLBW case volume at the hospital of birth.
Exposures: Level and volume of neonatal intensive care at the hospital of birth.
Main outcomes and measures: In-hospital mortality.
Results: There was a persistent trend toward deregionalization during the study period and mortality rates varied according to the level of care. High-level, high-volume (level IIIB with >100 VLBW cases per year and level IIIC) hospitals achieved the lowest risk-adjusted mortality. Infants with necrotizing enterocolitis born into midlevel hospitals (low-volume level IIIB and level IIIA NICUs) had odds of death ranging from 1.42 (95% CI, 1.08-1.87) to 1.51 (95% CI, 1.05-2.15, respectively). In the final year of the study, just 28.6% of the infants with necrotizing enterocolitis were born into high-level, high-volume hospitals. For infants born into lower level centers, transfer to a higher level of care frequently occurred well into the third week of life.
Conclusions and relevance: These findings represent an immediate opportunity for local quality improvement initiatives and potential impetus for the regionalization of important NICU resources.