Who's in the NICU? A population-level analysis.

Abstract

To understand the characteristics of infants admitted to US NICUs. 2006-2014 linked birth certificate and hospital discharge data for potentially viable deliveries in Pennsylvania and South Carolina were used. NICU admissions were identified using revenue codes. NICU-admitted infants were categorized by gestational age (GA), birthweight, and condition severity (for GA 35+ weeks). We also assessed total patient days and trends over time. 12% of infants were admitted to a NICU; 13.6% were GA < 32 weeks (45.3% of total days); 36.1% were GA 32-36 weeks (31.2% of total days); and 50.4% were GA 37+ weeks (23.5% of total days). 20% of admissions were for infants with GA 35+ weeks and mild conditions. Admissions increased numerically from 11.2% (2006) to 13.0% (2014), with increases among infants 35+ weeks. Most NICU admissions are for infants 35+ weeks GA, many with mild conditions who may be accommodated in well-baby units.