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The diagnostic accuracy of cerebral ultrasound for periventricular haemorrhage was determined by comparing this with necropsy findings in 30 preterm neonates of 30 weeks' gestation or less and birthweight under 1500 g. Ultrasound gave an accurate diagnosis of 85% in infants with germinal layer haemorrhage, 92% in intraventricular haemorrhage, and 97% in intracerebral haemorrhage. False positive errors were caused by vascular congestion; false negative errors occurred when the maximum dimension of haemorrhage was less than 3 mm. Cerebral ultrasound gave a diagnostic accuracy of 63% for periventricular leucomalacia. False negative errors occurred when periventricular leucomalacia was microscopic or when it was out of range of the scanner. The maximum width of the germinal layer was measured in 77 neonates of gestational age 23 to 36 weeks who died and had no periventricular haemorrhage at necropsy. The progressive involution of the germinal layer with increasing gestational age paralleled the steady decrease in incidence of periventricular haemorrhage diagnosed over the same gestational age range. Neonates of the youngest gestational age who had the most extensive germinal layers also had the highest risk for periventricular haemorrhage.

All 56 infants born between 23 and 28 weeks' gestation admitted to this hospital in 1981 were examined for periventricular haemorrhage with cerebral ultrasonography. Haemorrhage was diagnosed in 34 (61%)-12 (22%) had germinal layer haemorrhage, 18 (32%) had intraventricular haemorrhage, and four (7%) had intracerebral haemorrhage. The two year outcome of survivors with and without periventricular haemorrhage was compared to determine the effect on neurodevelopment. Only three (16%) of 19 infants with normal scans or germinal layer haemorrhages had evidence of major disability but nine (75%) of 12 infants with intraventricular or intracerebral haemorrhage had major disability. The mental and psychomotor performance on the Bayley scales of infant development was also significantly worse in the latter group. All three survivors with intracerebral haemorrhage had major disability. The continuation of life support treatment for extremely preterm infants who are at very high risk of severe handicap is a matter of increasing concern in neonatal intensive care. Our results show that if extensive periventricular haemorrhage, in particular intracerebral haemorrhage, occurs in this gestational group, extreme pessimism is warranted.

The perinatal histories of 50 very low birthweight infants weighing 1500 g, or less, with necrotizing enterocolitis were compared with those of the remaining 325 very low birthweight infants who were admitted to this hospital during a four year study period. Many factors previously reported to be associated with necrotizing enterocolitis were found with equal frequency in both groups of babies. The only adverse factor which was more frequently present in patients with necrotizing enterocolitis was hypothermia on admission to hospital. Those infants who developed severe necrotizing enterocolitis also had a higher incidence of polycythaemia. A further controlled study which examined feeding practices showed that the timing, type, and volume of milk feeding were not different in infants with necrotizing enterocolitis and matched controls. Prematurity is clearly the greatest risk factor which predisposes to the development of necrotizing enterocolitis and most of the factors previously implicated in the aetiology may simply represent the descriptive characteristics of a population of sick, very low birthweight infants.

34 preterm infants with birthweights

Twenty four infants with birthweights less than or equal to 1500 g had bronchopulmonary dysplasia (BPD). Four died in the neonatal period and four in the postneonatal period-one had been discharged and was aged one year. Sixteen (67%) survived long term and were followed up until they were two years old. Common medical conditions included respiratory illnesses in 14 (88%) children and otitis media in 8 (50%). Eleven (69%) required hospital admission for an average of 5 times; total days in hospital averaged 27 days. The most common reasons for admission were bronchiolitis and bronchopneumonia. At two years 37% were below the 10th centile for weight, as were 25% for height: head circumferences were normal. Two children had cerebral palsy, two had developmental delay, two had multiple disabilities, and one had sensorineural deafness. Of the 24 BPD infants, 8 (33%) died, 7 (29%) survived with a disability (severe in one), and 9 (38%) had a normal neurodevelopmental outcome. From the available perinatal data it was not possible to predict late disabilities in BPD survivors.

In a 4-year period the neonatal survival rate for 26 infants weighing 501-750 g was 42% and for 81 infants weighing 751-1000 g it was 61%. All 59 surviving infants have been assessed at follow-up; 39 were at least 2 years old (corrected for prematurity) and data from the remaining 20 were derived from assessment at 1 year corrected age. Five children had cerebral palsy, 4 had multiple handicaps, 4 each had a sensory handicap, 2 had developmental delay, and 1 had a dilated right ventricle without clinical hydrocephalus. Twelve of the 16 children with defined handicaps were considered to have significant functional handicaps. Therefore, of the 107 infants in this series, 48 (45%) died, 12 (11%) survived with significant functional handicaps, and 47 (44%) were considered to be developing within the normal range. No significant differences in the incidence of handicap were observed between inborn and outborn children, boys or girls, those who were small or appropriate for gestation, those who weighed less than or equal to 750 g or greater than 750 g at birth, and those who required or did not require prolonged oxygen or ventilation.

The effect of albumin priming on the plasma volume, intravascular bilirubin, and HBABA-binding capacity during the subsequent 2 to 4½ hours before exchange transfusion was studied in 7 jaundiced neonates with no haemolytic disease. After priming with albumin at a dose of 1·75 g/kg body weight as a 10% solution, there was a marked increase in plasma volume as well as total intravascular bilirubin and HBABA-binding capacity. However, the serum bilirubin concentration fluctuated only very slightly, largely because of the dilution effect of the expanded plasma volume. Both albumin and bilirubin gradually diffused out of the intravascular compartment again, but at the end of the observation period there was still a net gain of both. In another 20 neonates, the efficiency of exchange transfusion in removing bilirubin was compared. The efficiency was decreased by early albumin priming and enhanced by enriching the donor9s blood with albumin. It is concluded that albumin offers immediate and short-term protection against bilirubin toxicity, and albumin-priming should be useful in situations where the babies are admitted with high bilirubin levels and blood is not immediately available for exchange transfusion. Because of its effect on the plasma volume, albumin is not recommended for babies who are already hypervolaemic. If albumin is used to increase the efficiency of exchange transfusion, it should be given together with donor9s blood or shortly before the procedure.

The incidence of pulmonary air leak in 230 infants with a birth weight of 500-999 g who were ventilated was 41%. Pulmonary interstitial emphysema occurred in 35%, pneumothorax in 20%, pneumomediastinum in 3%, and pneumopericardium in 2%. The survival rates in those with or without pulmonary air leak were not significantly different in the first four years of the study period (46% v 53%). As the survival improved in infants without air leak during the second four years the difference in survival rates in infants with or without air leak became significant (30% v 71%). Effective measures of preventing pulmonary air leak are required before further improvement in the outcome of these extremely low birthweight infants can be achieved.

Fifty infants who weighed 1250 g or less at birth were studied with serial real time cerebral ultrasound to evaluate the temporal relation of various perinatal factors to the onset and progression of periventricular haemorrhage (PVH). The significant antecedents of PVH were severe bruising at birth, low birthweight, short gestation, ratio of arterial oxygen pressure (PaO2) to fractional inspired oxygen (FiO2), and haematocrit on admission, hyaline membrane disease, assisted ventilation, pneumothorax, administration of tubocurarine, hypercapnia, hypoxaemia, and hypotension. Case control studies, in which infants with PVH at 26 weeks' and 28 weeks' gestation were compared with matched infants without PVH, confirmed that the antecedents identified were independent of gestational influences. A multivariate discriminant analysis for the antecedents of PVH showed that hyaline membrane disease, hypercapnia, and short gestation correctly classified presence or absence of PVH in 78% of the study group. A similar analysis comparing infants with germinal layer haemorrhage or intraventricular haemorrhage with those who developed intracerebral extension of haemorrhage showed that three factors found on admission (hypothermia, a low PaO2:FiO2 ratio, and severe bruising) combined to classify correctly 90% of the haemorrhages. Our data suggest that prevention of perinatal trauma and asphyxia as well as respiratory illness, especially hyaline membrane disease, and stabilisation of blood gas tensions, blood pressure, and haematocrit within the physiological range, are likely to be the most effective ways of preventing PVH in extremely preterm infants.

Patent ductus arteriosus (PDA) was diagnosed in 27 (21%) of 129 infants weighing [unk] 1500 g at birth presenting over 1½ years. The incidence of PDA in infants with pulmonary disease, particularly hyaline membrane disease, was higher than that in infants without such disease (31% compared with 16%). 16 (59%) infants with PDA developed congestive cardiac failure (CCF), of whom 12 were [unk] 1000 g at birth. Eight of these infants had persistent CCF despite aggressive antifailure treatment, and 8 were ventilator-dependent although stable on medical management. Pharmacological ductal closure with indomethacin was attempted in these 16 infants according to clinical and echocardiographic criteria. Complete or partial ductal closure with clinical and echocardiographic improvement was achieved in 75% of infants. Treatment with indomethacin failed in 4 infants all of whom were [unk] 1000 g at birth and had gestational ages [unk] 26 weeks. Two of these infants had surgical ligation of the PDA and recovered. No morbidity was attributed to indomethacin except for transient oliguria. Overall survival was 76%; this ranged from 50% in infants weighing 501-750 g, to 91% in infants weighing 1251-1500 g. Results suggest that (1) extremely preterm infants are less likely to respond to indomethacin, (2) success is more likely in the first 10 days of life, (3) a total dose greater than 0·6 mg/kg will not increase the success rate, (4) selective morbidity from indomethacin is unlikely if the contraindications of bleeding tendency, hyperbilirubinaemia, and renal dysfunction are followed, although urinary output must be monitored carefully, (5) indomethacin is a useful alternative to surgical ligation although long-term prognosis from clinical trials has yet to be established.

Our previous cerebral ultrasound study of antecedents of periventricular haemorrhage in infants weighing 1250 g or less at birth suggested that neonatal events that caused increased or fluctuating cerebral blood flow lead to periventricular haemorrhage. As the risk period for this type of haemorrhage was the first four days of life strict guidelines were introduced to avoid the previously identified neonatal risk factors. No attempt was made to modify obstetric practice. Over the next two years, although the obstetric risk profile, the frequency and severity of hyaline membrane disease, and the gestation, birth weight, and sex distributions of a similar cohort of infants did not change, the incidence of periventricular haemorrhage decreased significantly from 60% to 36%. Significant antecedents of haemorrhage similar to those found in the previous study included severe bruising, low arterial:fractional inspiratory oxygen ratio and low packed cell volume on admission, hyaline membrane disease, hypercarbia, and hypoxaemia. Assisted ventilation, pneumothorax, treatment with tubocurarine, and hypotension were no longer significant risk factors for periventricular haemorrhage. A multivariate discriminant analysis correctly predicted haemorrhage in 86% of the study group when bruising, hypercarbia, hypoxaemia, hyaline membrane disease, and low gestation were considered. These results suggest that changes in neonatal practices can reduce the incidence of periventricular haemorrhage and that drug studies indicating similar reduction in haemorrhage need to be evaluated carefully to ensure that placebo and treated groups are in fact comparable.

We report a minicomputer based recording, reporting, and research system for patient data management in the neonatal intensive care unit (NICU). It is moderately priced, transportable, and independent of a central computer. It requires only a desk top and standard power supply, and successfully meets the medical documentation, communication, and research needs of the NICU. The first phase of programme development has enabled us to process growth and nutritional data from infants on complex parenteral and enteral nutrition. The system is well suited to medical users and provides a practical interactive data management system with many potential applications in the NICU.