Survival after necrotizing enterocolitis in infants weighing less than 1,000 g: 25 years' experience at a single institution

Necrotizing enterocolitis (NEC) primarily affects premature newborns. Regional and national decreases in the mean birthweight and gestational age of neonatal intensive care unit (NICU) admissions prompted a review of NEC in VLBW (very low birth weight, defined as < 1,000 g) infants in our institution over a 25-year period. There were 266 patients treated for NEC during the study interval. We compared 71 VLBW with 195 non-VLBW infants and found that VLBW infants were: fed later (6.4 days v 4.1 days, P = .009), developed NEC later (20.8 days v 13.1 days, P = .002), had significantly lower 1- and 5-minute Apgar scores, were more likely to require surgery (51% v 34%, P = .016), more often had panintestinal (defined as > 75% of intestinal length) involvement (10% v 4%, P = .043), and had poorer survival (56% v 72%, P = .013). Overall survival after NEC has improved over the study interval, both in our series and in other reports. However, the increasing number of VLBW infants who have NEC represent a subgroup who appear to be generally more ill, develop NEC later, require surgery with greater frequency than their non-VLBW counterparts, and are less likely to survive.