Fit to fly: practical challenges in neonatal transfers by air.

Air transport of infants in incubators should be undertaken in a manner that is safe for both staff and infant and satisfies all directives by appropriate regulatory bodies. In Scotland during the last two years, certification of an infant incubator system for use in both rotary and fixed wing aircraft has been accomplished. This is a report of the issues addressed during this project, which will be common to all neonatal transport services intending to develop air transport capability.

Optimising neonatal transfer.

Services for neonatal intensive care in the United Kingdom have evolved in a largely unplanned fashion. Units of different sizes provide various amounts of intensive care, and, with a few exceptions, there is little or no formal regional or subregional organisation. Chronic underresourcing and the salvaging of ever more complex infants have resulted in tertiary neonatal intensive care units operating at full capacity most of the time, a situation compounded by a chronic national shortage of nursing staff. These factors have in turn resulted in an increase in requirements for emergency perinatal transfers.

Early perfluorodecalin lung distension in infants with congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Pulmonary hypoplasia contributes to mortality in infants with severe congenital diaphragmatic hernia (CDH). Accelerated postnatal lung growth with perfluorocarbon lung distension has been demonstrated in animals. The authors present a study measuring perfluorodecalin distension in neonates with severe CDH on extracorporeal membrane oxygenation (ECMO) support. METHODS: Six consecutive neonates with CDH requiring ECMO support were recruited. The lungs were filled with perfluorodecalin, and continuous positive airway pressure was applied for 6 to 10 days (mean, 7.7 days +/- 0.7). The perfluorodecalin was exchanged 4 times a day. Radiographic lung projections were measured, and from 2-dimensional measurements an estimated lung volume was calculated using the ECMO cannula as reference. RESULTS: Perfluorodecalin instillation started soon after starting ECMO support (mean, 13.5 +/- 5.3 hours). The volume required to fill the lungs increased significantly (P <.02). The radiographic dimension of the affected lung increased significantly (mean percentage increase, 272%; P <.02). The contralateral lung dimension also increased (mean percentage increase 51%; P <.02). CDH repair was undertaken on ECMO in all cases. All patients survived (follow-up, 3 to 42 months). CONCLUSIONS: This protocol of early perfluorodecalin lung distension in infants with severe CDH on ECMO support resulted in significant radiographic lung enlargement. Clinical outcomes are encouraging. Possible mechanisms include alveolar recruitment, alveolar dilatation, and accelerated postnatal lung growth.

Endothelin-1 levels in infants with pulmonary hypertension receiving extracorporeal membrane oxygenation.

We studied the possibility of an etiological role for endothelin-1 (ET-1) in the development of persistent pulmonary hypertension of the newborn (PPHN). Ten infants with severe PPHN requiring extracorporeal membrane oxygenation (ECMO) were studied. Pre and post pulmonary blood samples were obtained on commencing ECMO and on recovery. The samples were analyzed by radio-immunoassay. The infants with PPHN requiring ECMO had a significantly higher mean ET-1 concentration (21.1 pmol/l, S. D. 3.59) than a group of healthy controls (16.6 pmol/l, S. D. 4.44); however 8 of our 10 infants had individual ET-1 levels within our reference range for healthy newborns. Pre and post pulmonary ET-1 levels did not differ significantly and there was no evidence of a decline in ET-1 levels with resolution of PPHN. Pulmonary overproduction of ET-1 does not appear to be the cause of PPHN, although the endothelin system may still play a role in the pathophysiology of PPHN, probably mediated through changes in receptor expression.

Bone marrow gene transfer in three patients with adenosine deaminase deficiency.

Adenosine deaminase (ADA) deficiency results in severe combined immune deficiency disease (SCID), which is fatal without treatment. Allogeneic bone marrow transplantation (BMT) is the treatment of choice if an HLA-identical sibling bone marrow donor is available, resulting in almost 100% cure rate. BMT-related mortality is high in patients lacking such a donor. For these patients, efficient transfer of a recombinant ADA gene into hematopoietic stem cells is a therapeutic option if it results in the outgrowth of a 'genetically repaired' lymphoid system. Based on successful gene transfer studies in monkeys, we performed retrovirus-mediated gene transfer into CD34+ bone marrow cells of three patients with ADA deficiency. Two patients received bovine ADA conjugated to polyethylene glycol (PEG-ADA); in the third patient, PEG-ADA was started 4 months after gene transfer. Gene transfer resulted in a 5-12% transduction frequency of in vitro colony forming cells (CFU-Cs). No toxicity was observed during and after infusion of the graft. Following infusion of the transduced CD34+ cells, transduced granulocytes and mononuclear cells persisted in the circulation for 3 months. In addition, the gene was present in the marrow of one of the patients at 6 months after gene transfer. Expression of the gene was not detected. After this period, the gene could not be detected. In monkey studies we showed that myeloablation, which was not performed in the patients, may enhance engraftment of genetically modified cells. We hypothesize that lack of myeloablation, administration of bovine ADA and low numbers of transduced progenitor cells all may have contributed to the relative low numbers of transduced cells in the patients. Under these conditions, no selective advantage of the genetically corrected progenitor cells was observed.

Randomised trial of continuous nasogastric, bolus nasogastric, and transpyloric feeding in infants of birth weight under 1400 g.

Forty three infants under 1400 g were fed by a bolus nasogastric, continuous nasogastric, or transpyloric route. There were more complications with transpyloric feeding and no identifiable benefits in the growth rate, oral energy input, or chosen biochemical indices of nutrition. Bolus or continuous nasogastric feeds rather than transpyloric are better routine methods in infants of low birth weight.

Genetic aspects of admissions to a paediatric intensive care unit.

Of 821 consecutive admissions to a paediatric intensive care unit, 47 (5.7%) were for chromosomal or monogenic disorders. These patients had more readmissions, longer mean stays, and a higher mortality rate than the group as a whole. In two of the four cases that died of single gene disorders, failure to store DNA made genetic counseling difficult.

Nephroblastoma presenting with acute hepatic encephalopathy.

A 3 year old girl presented with Budd-Chiari syndrome of acute onset, and hepatic encephalopathy secondary to intravascular extension of a Wilms' tumour shown on echocardiography. After a period of intensive medical treatment the tumour was removed, cardiopulmonary bypass with hypothermic circulatory arrest being necessary. Her hepatic failure resolved and she made a complete neurological recovery.

Abnormal sweat electrolytes in symptomatic human immunodeficiency virus infection in a child.

A 3 1/2 year old girl presented with failure to thrive and a five month history of diarrhoea and recurrent cough. The results of sweat sodium tests suggested a diagnosis of cystic fibrosis; but atypical organisms were found (Haemophilus influenzae, Candida albicans, but no Staphylococcus aureus), she failed to respond to treatment, and her sweat sodium concentrations fell in response to fludrocortisone. She also had hyperglobulinaemia, neutropenia, and reduced numbers of T4 lymphocytes, which prompted the performance of a test for antibody to human immunodeficiency virus (HIV). This proved positive, and she was treated with co-trimoxazole, zidovudine, and human immunoglobulin. Both parents and two siblings were also positive for HIV, though all had normal sweat sodium concentrations. Children with symptoms suggestive of cystic fibrosis but who also show atypical features, as in this case, should have their HIV state checked.