Mortality and major morbidity in premature infants less than 31 weeks gestational age in the decade after introduction of surfactant.

OBJECTIVE

Population- but also center-based mortality and major morbidity rates of premature infants are essential for prenatal counseling and quality control.

METHODS

Records of all infants <30 + 6 weeks (n=674) admitted (1991-2000) to a single neonatal intensive care unit were reviewed and compared to the state-wide mortality.

RESULTS

Six hundred and ninety-one infants were born in or transferred to the hospital and 600 infants (89%) survived. The mean (SD) birth weight was 1018 g (+/-314) and the mean gestational age 27+5 weeks (+/-2.0). Mortalityand morbidity did not change significantly over the 10-year period but correlated inversely with gestational age from 45% at 23(0/7) weeks to 5% at 30(6/7) weeks. Study center mortality rate for extremely low birth weight infants with birth weight <750 g was significantly lower than reported for the entire state (local 25%; Bavaria 36% p = 0.0003). Thirty-four per cent (251/600) of the survivors had one or more major complications: intracranial hemorrhage III-IV 8% (88/600), periventricular leucomalacia 6% (41/600), bronchopulmonary dysplasia with oxygen requirement at 36 weeks 20% (128/600), necrotizing enterocolitis 6% (43/600), and retinopathy of prematurity grade III-IV 9% (55/600). Survival without major morbidity increased from 32% at 23 weeks to 92% at 30 weeks.

CONCLUSIONS

Despite changes in obstetric and neonatal care during the 1990s, mortality and major morbidity rates did not change significantly after the introduction of surfactant in 1991. Comparison of local, regional, national, and international mortality and morbidity rates are becoming more important in allocating resources and in decision-making at the limits of viability.