Improving prognosis for infants weighing 1000 g or less at birth.

In the two years 1977 and 1978, 55 infants weighing less than or equal to 1000 g were admitted to the neonatal unit of the Queen Victoria Medical Centre. Overall neonatal survival was 60%; 44% of infants weighing 501-750 g and 67% of infants weighing 751-1000 g survived. One postneonatal death occurred at 51 days. Maternal risk factors were present in 80% of infants, although none had an effect on survival. Perinatal asphyxia, as indicated by an Apgar score less than or equal to 3 at five minutes, and base deficit greater than 10 mmol/l on admission, were associated with decreased survival. Mortality data with increasing postnatal age were used to produce a chart for sequential predication of neonatal survival. Intraventricular haemorrhage remained the most common necropsy finding. Follow-up of 32 survivors to date has shown no abnormalities, with the exception of one retrolental fibroplasia, and one porencephaly of unknown aetiology. We conclude that the prognosis for infants weighing less than or equal to 1000 g has continued to improve. From a review of the clinical and pathological characteristics in these infants however, it is obvious that this outcome requires complex organisation and costly resources in perinatal centres to which high-risk pregnancies must be transferred for optimal management both before and after birth.