Prediction of respiratory distress syndrome by the microbubble stability test on gastric aspirates in newborns of less than 32 weeks' gestation.

AIM: There is a need for a rapid method to identify infants who will develop respiratory distress syndrome (RDS) soon after birth, to allow early treatment of affected infants with surfactant. The microbubble stability test (MST) may be one such method, but clinical experience is sparse. METHODS: The MST was performed on gastric aspirates from 188 infants with a mean gestational age of 29 (range 23-31) wk. RESULTS: 87 infants developed moderate to severe RDS, corresponding to a prevalence of 46%. The sensitivity, specificity and predictive values for identification of infants with moderate to severe RDS were determined for the average diameter of bubbles, the proportion of microbubbles with different diameters and the total number of microbubbles. The proportion of microbubbles with diameters <20 or 25 microm gave the best prediction, with a sensitivity of 78-79%, a specificity of 57-58%, a positive predictive value of 62% and a negative predictive value of 76%. Early treatment with nasal continuous positive airway pressure probably mitigated the development of RDS in some infants with a low-degree surfactant deficiency and this may explain the relatively low specificity. CONCLUSION: In infants of <32 wk gestation RDS can be predicted by computerized image analysis of the size distribution of microbubbles generated in gastric aspirates.

[Emergency transport of newborn infants--fetch or bring?]. / Akut overflyttelse af nyfødte børn--hente eller bringe?

INTRODUCTION: Neonatal transport is difficult and often associated with problems. In 1998, the Neonatal Intensive Care Unit, University Hospital of Copenhagen, H:S Rigshospitalet, set up a neonatal transport team. The aim of this study was to assess whether a better quality of high risk transport could justify the increased consumption of time. METHOD: The schedules for observation and assessment filled in by the transport team were collected and compared with records of the transport of high-risk neonates by local transport. The comparison consisted in the number of infants, severity of the problems, interventions carried out either locally or after arrival at the Neonatal Intensive Care Unit, and the condition of the infants judged on the pH, blood sugar level, blood pressure, and body temperature. RESULTS: The neonatal transport team fetched 68 high-risk infants, whereas 140 high-risk infants were brought by local transport. Infants fetched by the transport team were more sick, both before and during transport, than those brought to us. On arrival at the Neonatal Intensive Care Unit, more infants brought by local transport had problems (31% vs 16%): 12 (9%) transports had more than one critical problem, in contrast to none of the infants fetched by the transport team. The transport team carried out 71 interventions on 44 of the 68 infants (65%). These interventions explain the better condition of the infants on arrival. Acute interventions soon after arrival at the Neonatal Intensive Care Unit were carried out on 91 of the 140 infants brought by local transport (65%). DISCUSSION: Neonatal transport of extremely ill infants is difficult. A specialised (transport) team with local stabilisation and transport reduces the frequency of complications. The number of high-risk neonates transported is so small that it is improbable that adequate expertise can be built up and maintained locally.

[The first Danish experiences with neonatal extracorporeal membrane oxygenation]. / De første danske erfaringer med neonatal ekstrakorporal membranoxygenering.

In 1995, neonatal extra-corporeal membrane oxygenation (ECMO) was established at the Department of Neonatology, Rigshospitalet, Copenhagen. The indication for ECMO is circulatory or respiratory failure with arterial oxygen tension below 8 kPa despite maximal conventional treatment. During the first two and a half years 17 newborn infants and one child of 21 months have been treated with ECMO at the Rigshospital. Fifteen survived, of 12 followed at least nine months, 11 have normal development and one has cerebral palsy. There were problems including surgical placement of the cannula, technical difficulties or bleeding in 12 patients. During the same two years at least eight newborns in Denmark fulfilled the ECMO indication, but were not treated, half were not transferred to the Rigshospital. Seven of these eight infants died. The need for ECMO treatment in newborn infants is documented but small. We have succeeded in establishing this complicated treatment due to teamwork between different specialities with a good result.

Lung hypoplasia--a possible teratogenic effect of valproate. Case report.

Three cases of lung hypoplasia occurring in two siblings and in an unrelated child are reported. All three cases had been exposed to valproate in utero. The two female siblings had no other malformations, whereas the third female had a number of defects consistent with the fetal valproate syndrome. Thus, none of the known major causes of lung hypoplasia was present in any of the three cases. It is discussed whether pulmonary hypoplasia may be a separate disease entity, or caused by prenatal exposure to valproate.

Retinopathy of prematurity: review of a seven-year period in a Danish neonatal intensive care unit.

In the period 1985-1991, 21,675 infants were born at the University Hospital of Copenhagen, Hvidovre Hospital, Denmark. Two hundred and twenty-four infants (10.3%) with birth weights < or = 1500 g and gestational ages < or = 32 completed weeks were transferred to the neonatal intensive care unit of the hospital. One hundred and eighty survived to at least 8 weeks of age and 170 had eye examinations. Forty-five of the 170 infants examined (26.5%) had retinopathy of prematurity (ROP) and 18 (40%) of these developed blindness or severely impaired vision, a higher incidence than reported in other studies. Significant differences were found between infants with and without ROP for: birth weight, gestational age, Apgar score at 1 min, resuscitation, ventilator treatment, duration of supplementary oxygen, severe complications in the neonatal period and sequels from the central nervous system. Statistical analysis, corrected for correlations, showed that the occurrence of ROP was related significantly to early intubation, hypotension, persistent ductus arteriosus and necrotizing enterocolitis.

[Morbidity, mortality and late sequelae in extremely premature infants born in the Hvidovre Hospital, 1985-1991]. / Morbiditet, mortalitet og senfølger hos ekstremt tidligt fødte børn på Hvidovre Hospital, 1985-1991.

In the period 1985 to 1991, 80 infants with gestational age below 28 completed weeks were born at Hvidovre Hospital, Copenhagen and transferred to the neonatal intensive care unit of the hospital. The incidence of extreme prematurity was 3.6 0/00. Twenty-eight infants died during the neonatal period (35%) and nine infants died later in infancy (11.3%). Forty-three infants (54%) survived. Forty four percent of surviving infants had one or more sequelae related to their prematurity or neonatal complications, mainly blindness or reduced vision, cerebral palsy and mental retardation. Neither gender, mode of delivery or birth asphyxia were important for survival and sequels. Neonatal complications such as patent ductus arteriosus, septicaemia, necrotizing enterocolitis, pneumothorax and cerebral haemorrhages were significantly related to survival and sequelae.

[Survival in relation to gestational age in delivery before 32 complete weeks of pregnancy with low birth weights, 1,500 g or under]. / Overlevelse i relation til gestationsalder ved fødsel før 32 fulde gestationsuger med lav fødselsvaegt, 1.500 g eller under.

In a retrospective study, all deliveries at Hvidovre Hospital, Copenhagen, with birth weights < or = 1500 g and gestational ages of 23 to 32 completed weeks were examined to find out how they were recorded and the survival of the baby. Sixty-one were registered as abortions, 151 as births. Sixteen infants (10.2%) were registered as stillborn and 9 (6.7%) were live born without major malformations but died in the delivery ward without transfer to the neonatal intensive care unit (NICU) of the hospital. The survival for infants without severe malformations was 72.4% for all liveborn infants, and 77.6% for infants transferred to the NICU. The youngest surviving infant was born after 24 completed weeks of gestation. Because of different criteria for selection, comparison between different studies is difficult. This investigation shows that registration of very premature deliveries can be heterogenous. This is of great importance for survival and outcome rates because of the small number of very premature infants. We suggest a registration of all deliveries taking place after 22 completed weeks of gestation including birth weight, gestational age, pulse, respiratory movements, lethal malformations and time of death to ensure a better knowledge of the prognosis of these tiny infants.

Retinopathy of prematurity in a Danish neonatal intensive care unit, 1985-1991.

During the 7 year period 1985 to 1991, 170 infants born in Hvidovre Hospital, Denmark, with birthweight < or = 1500 g and gestational age < or = 32 completed weeks survived at least 8 weeks or more and had eye examinations carried out. Forty-five infants had ophthalmoscopic evidence of retinopathy of prematurity (ROP). Eighteen developed blindness or severely reduced vision and 6 developed unilateral blindness. In 21 the ROP changes regressed. Eight infants eventually developed severe myopia. The 45 infants with ROP were compared with the 125 without ROP. There was no difference in birth weight, gender, or mode of delivery. Significant difference was found in gestational age, asphyxia, intensive treatment and complications. Particularly infants with ROP born with gestational age 27 to 29 weeks needed prolonged and more intensive treatment than infants without ROP. Infants with ROP had more frequently long term sequels from the central nervous system than infants without ROP.

[Computer-assisted respirator treatment of neonates]. / Computervejledt respiratorbehandling af nyfødte.

A retrospective investigation was undertaken to assess the value of a knowledge-based computer programme for improved respirator treatment of neonates in ventilators. On the basis of the arterial gas values from 30 premature infants with birthweights of under 1,500 g and suffering from the respiratory distress syndrome, the alterations in ventilator settings which were made were compared with the suggestions made by the programme. The programme was in agreement with the written instructions in the department. Complete agreement was found between the adjustments actually made and those suggested by the programme in 37.5% and complete or partial agreement in 68% of the infants. Agreement was poorest among the infants who died from respiratory insufficiency or who developed pneumothorax. A frequent cause of defective agreement was that ventilator settings were not adjusted according to the gas values recorded. The sequel of this was most frequently absence of improvement or deterioration in the subsequent gas values. This occurred most frequently during night hours. This investigation reveals that respirator treatment of neonatal infants is difficult and that easily accessible qualified advice is required.

The risk of X-ray examinations of the lungs in neonates.

X-ray examinations of the lungs is an important element in the evaluation of the neonates and their respiratory function. It is often necessary to perform a large number of X-ray examinations depending upon the infant's birthweight, gestational age and respiratory problems. To estimate the risk of X-ray examinations of the lungs the radiation dose to 18 infants at the Neonatal Intensive Care Unit, Hvidovre Hospital, was measured by means of a thermoluminescent dosimeter placed on the nipple of the infant. The radiation dose to various organs was estimated and the risk weighted whole body radiation dose calculated to 40 microsievert per examination (AP- and lateral). Using the latest increased risk factors this means an excess cancer mortality of 5 x 10(-5) for boys and 11 x 10(-5) for girls per millisievert, corresponding to 25 X-ray examinations (AP- and lateral) of the lungs. It is concluded, that even using the latest increased risk factors, the radiation risk of repeated X-ray examinations of the chest in prematures will be very low considering the benefit for the infant.

A computerized aid in ventilating neonates.

A computer program for ventilating neonates using a volume controlled ventilator is presented. The program proposes directions for changes of ventilator settings decided from the actual arterial blood gas samples and ventilator settings. The program deals with up to six babies at the same time and contains a continuous evaluation of the last six values of pCO2 and pO2 resulting in statements and warnings in potentially harmful situations. The program is consistent with the written instructions of the department. The ventilator treatment of 30 premature babies is evaluated retrospectively using the program, showing a total agreement of 37.5%, lowest among the babies who died in respiratory insufficiency. The advantage of the use of the program is discussed.

[Zinc deficiency in a premature infant]. / Zinkmangel hos praematurt spaedbarn.

A premature infant with a birth-weight of 1,218 g developed severe zinc depletion about two months after birth. He had received his mother's breast-milk which was found to have a low zinc content of about 5 mumol/l. The clinical symptoms of zinc deficiency included stunted growth, catarrhal symptoms and a characteristic eczematous eruption on the face and diaper region known as acrodermatitis. Serum zinc was lowered (6.8 mumol/l) and so was serum alkaline phosphatase activity. Oral zinc sulphate supplementation, initially 22.5 mg daily and subsequently 11 mg zinc daily, had a prompt effect on the patient's well-being and the skin was restored to normal after about a week.

Early fatal nemaline myopathy: case report and review.

A newborn girl with atonia and arthrogryposis multiplex required mechanical ventilation; she died on the 14th day. Postmortem muscle histology disclosed nemaline myopathy with a lack of myofibrils. Peripheral nerves appeared to be normal. The parents are first cousins. The findings for 13 other patients who died from nemaline myopathy within the first year of life are reviewed. It is suggested that early fatal cases, in contrast to patients with the 'benign' childhood form, are homozygotic for the disease gene, and that the myopathy results from abnormal myosin synthesis.

The effect of different sulfonamides on phenytoin metabolism in man.

The influence on the metabolism of phenytoin of some sulfonamides given in common clinical doses has been studied. In single dose experiments sulfaphenazole increased phenytoin half-life (T/2) by 237% and decreased phenytoin metabolic clearance rate (MCR) by 67%. Sulfadiazine, sulfamethiazole, sulfamethoxazole + trimethoprim and trimethoprim increased phenytoin T/2 by 80, 66, 39 and 51% respectively, and decreased phenytoin MCR by 45, 36, 27 and 30% respectively. Sulfamethoxazole gave a small but significant increase in phenytoin T/2 but not a corresponding fall in phenytoin MCR. No changes were found in phenytoin T/2 and MCR after treatment with sulfamethoxypyridazine, sulfadimethoxine and sulfamethoxydiazine. Steady state experiments confirmed the findings of the single dose experiments. It is suggested that sulfaphenazole, sulfadiazine, sulfamethizole, sulfamethoxazole + trimethoprim and trimethoprim inhibit hepatic metabolism of phenytoin.