Infants with gestational age 28 weeks or less: Impact of neonatal treatment and complications on outcome

The objective of the study was to evaluate neonatal survival and subsequent disabihties in infants with extremely low gestational age in relation to perinatal events and neonatal treatment. A retrospective follow-up study was performed based on medical records, questionnaires to parents and recordings of contact with health authorities. All infants with a gestational age of 28 completed weeks or less, who were admitted to the Department of Neonatology. Rigshospitalet, within 24 hours of age during the period January 1, 1987 - December 31, 1990 were included. During this period the basic therapeutic approach was a combination of minimal handling and early nasal-continuous positive airway pressure (CPAP) ("minitouch"). Main outcome measures were: mortality, healthy survival and disabled survival. Variables related to outcome were: risk factors present at birth (gestational age, birth weight, gender, place of birth (Rigshospitalet/other hospital), mode of delivery, Apgar score at five minutes; interventions in the neonatal period (intermittent positive pressure ventilation and treatment of hypotension); complications in the neonatal period (intracranial haemorrhage grade II-IV, periventricular leucomalacia, pneumothorax, seizures and septicaemia). One hundred and ninety-seven infants without major malformations were included. The mortality rate was 29%. Among infants with gestational age 24-25 weeks 49% died versus 24% of infants born after 26-28 weeks (p=0.004). Mean gestational age was 26.7 weeks (range 24-28) and mean birth weight 994 g (range 525-1630). Fifty-five infants (28%) were small-forgestational age. One hundred and fifty-five infants (79%) were born in our hospital and 115 (58%) were delivered by caesarean section. A total of 140 infants (71%) survived until discharge and none died between discharge and follow-up. At follow-up at a mean uncorrected age of 48 months information was obtained about all infants, except two (1%) who had emigrated; 75 (54%) had no impairments, 31 (22%) had minor impairments, 17 (12%) were moderately disabled, and 15 (11%) were severely disabled. Of the 197 infants 121 (61%) were treated with intermittent positive pressure ventilation, 83 (42%) with dopamine for hypotension, and 92 (47%) received parenteral nutrition. In 64 infants (33%) the course was complicated with intracranial haemorrhage (ICH) grade II-IV, in 17 (9%) with seizures, in 23 (12%) with pneumothorax, in 21 (11%) with septicaemia, and in 10 (5%) with necrotizing enterocolitis. Sixty infants (31%) needed medical or surgical closure of a persistent ductus arteriosus. In 11 infants (6%) cystic periventricular leucomalacia occurred, 10 infants (5%) developed retinopathy of prematurity stage 3-4, and 35 infants (24%) received supplementary oxygen at 28 days of age. Risk factors present at birth for adverse outcome were: Apgar score <7 at five minutes, birth weight <1000 g, male sex and birth in another hospital than Rigshospitalet. For adverse outcome in surviving infants only, ICH grade II-IV was the only significant risk factor.