1413 FOLLOW-UP OF INFANTS 501–1500 GM BIRTHWT. DELIVERED TO RESIDENTS OF A GEOGRAPHICALLY DEFINED REGION WITH PERINATAL INTENSIVE CARE FACILITIES

In an attempt to minimize the selection bias inherent in reporting the outcome of premature infants from a particular Neonatal Intensive Care Unit (NICU), this study presents data on all 294 live births 501-1500 gm birthweight born to residents in the Hamilton-Wentworth Region during 1973-78. The survival rate was 31.9% in infants ≤1000 gm compared with 82.6% in infants between 1001-1500 gm. In all, 184 infants (62.6%) were discharged alive and 37 of these weighed ⩽1000 gms. The mean BW of the survivors was 1216 ± 214 gm and the mean gestation was 30.0 ± 2.9 wks with 18.0% being small-for-gestational-age. Respiratory Distress Syndrome (RDS) occurred in 40% and assisted ventilation (IPPV) for RDS and/or apnea was used on 33% of survivors. A prospective follow-up was performed on 136/184 survivors born and/or transferred to the Regional NICU; a single assessment was obtained on the remaining 48 survivors born and treated in the Community Hospitals. Five infants (2.7%) were lost and another 5 infants (2.7%) died after discharge. Major neurological handicaps including cerebral palsy, hydrocephalus, microcephaly, blindness, deafness and mental retardation occurred in 30/179 (16.8%) infants. The incidence of major handicaps was 30% among babies who received IPPV, versus 10% in those who did not. Within the IPPV and non-IPPV groups, there were no significant differences in handicap rates by 500 gm BW class.