Abstract 1464 Neonatal Epidemiology and Follow-up Poster Symposium, Monday, 5/3

Care of the extremely premature newborn in the United States has historically been more aggressive than in some European countries. To determine the relative cost-effectiveness of more aggressive intensive care, resource utilization and outcomes of two population-based cohorts of premature infants born in the mid-1980s were compared. The Newborn Brain Hemorrhage (NBH) cohort included livebirths 500-2000g in a three county area of central New Jersey in 1984-1987 (n=1105). The Project on Preterm and Small for Gestational Age Infants (POPS) included livebirths <1500g or <32 wks of gestation in The Netherlands in 1983 (n=1338). The difference in the aggressiveness of care was most pronounced in infants <27 weeks; the analysis was, therefore, limited to infants >499g and 23-26 wks(n=152 in NBH and n=144 in POPS).

Infants in the NBH cohort were much more likely to be delivered by cesarean section: 30.1% of NBH livebirths were delivered by cesarean section compared to 5.6% of POPS livebirths (p<0.001). They also were much more likely to be treated with mechanical ventilation (MV) than those in the POPS cohort: 95.4% of NBH livebirths were treated with MV compared to 64.7% POPS livebirths (p<0.001). Almost all survivors in both cohorts (97% in each) received MV. However, only 6.2% of NBH deaths occurred without MV, whereas 44% of POPS deaths occurred without MV (p<0.001), indicating a much more selective application of intensive care in the latter cohort. A total of 1776 ventilator days and 3234 non-MV hospital days were expended per 100 livebirths in the NBH cohort; 449 MV days and 2504 non-MV days were expended per 100 livebirths in the POPS cohort. Survival to age 2 in the NBH cohort was twice that in the POPS cohort: 47.3% v 22.9% (p=0.001). The prevalence of disabling cerebral palsy (DCP) among survivors was almost 5 fold higher in the NBH than in the POPS cohort (15.9% v 3.5%); therefore, there were 7.5 survivors with DCP per 100 livebirths in the NBH and 0.8 per 100 livebirths in the POPS cohort (p=0.03). [We have elsewhere shown high reliability for distinguishing children with from children without DCP in both cohorts by investigators from both cohorts (average Kappa=0.88)]. Thus, more aggressive application of intensive care in the NBH cohort resulted in 24.5 additional survivors per 100 livebirths and 6.7 additional cases of DCP per 100 livebirths than did less aggressive intensive care in the POPS cohort. 77 additional days of MV and 42 additional non-MV hospital days were expended in the NBH cohort for each additional survivor without DCP per 100 livebirths, compared to the POPS cohort.