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Hypoglycaemia has long been recognised as a feature of the failure of metabolic adaptation in infants who are small for gestational age (SGA). This study examined the process of metabolic adaptation by measuring, longitudinally, the concentrations of metabolic fuels and substrates in 33 SGA infants in the first postnatal week, and relating these to cross sectional data in 218 infants of appropriate weight for gestational age (AGA). SGA term infants had higher mean blood lactate concentrations than AGA term infants at delivery (2.98 v 2.10 mmol/l) and in the first few postnatal hours (3.05 v 1.91 mmol/l). Subsequently, although there were no differences in blood glucose concentrations, SGA term infants had lower mean ketone body concentrations (for example day 2: 0.07 v 0.41 mmol/l), and failed to mount a ketogenic response to low blood glucose concentrations. At birth, SGA preterm infants had lower mean blood glucose concentrations than AGA preterm infants (3.17 v 4.16 mmol/l), but there were few postnatal metabolic differences between the two groups. Mean blood glucose concentrations did not differ between AGA and SGA preterm infants. For variables that differed between the groups, multiple regression analysis suggested that both the degree and asymmetry of growth retardation were related to the severity of the metabolic abnormalities. These data suggest that, although there are early metabolic differences between SGA and AGA infants, it is possible that current clinical management is effective in preventing subsequent hypoglycaemia. This is important because of the failure of SGA infants to mount a ketogenic response.

Neonatal hypoglycaemia is a common clinical problem and the traditional treatment for the condition is intravenous glucose administration. The glycaemic effects of two additional treatments were investigated, in a randomised trial, in 23 neonates who were receiving intravenous glucose as treatment for hypoglycaemia. Eleven infants received an intravenous bolus dose of glucagon (200 micrograms/kg) and 12 infants received intragastric medium chain triglyceride (MCT) (5 ml/kg). Blood concentrations of glucose and intermediary metabolites were measured before and one hour after treatment, and, using stable isotope infusion, glucose production rates were calculated. After glucagon, there was a mean rise in blood glucose concentration of 1.6 mmol/l and in the glucose production rate of 2.6 mg/kg/min. After MCT, there was a small mean rise in blood glucose concentration of 0.4 mmol/l, but the effect of MCT on glucose production rate was variable. Intravenous bolus glucagon administration exerted a glycaemic effect which was associated with an increase in glucose production rate. The use of glucagon, as an alternative treatment to intravenous glucose, should be investigated further.

Little is known of the ability of hypoglycaemic infants who are small for gestational age (SGA) to mount the coordinated hormonal and metabolic counterregulatory response that is seen in healthy older subjects during glycopenia. This response was studied in 22 SGA infants (birth weight < 10th centile) by measuring the blood concentrations of glucose, intermediary metabolites, and glucoregulatory hormones. Plasma non-esterified fatty acid and blood ketone body concentrations were low, even when blood glucose concentrations were low. Plasma insulin and glucagon varied widely (< 1.0-53.1 mU/l and 16.6-87.1 pmol/l, respectively). Concentrations of noradrenaline and glucagon were raised, but cortisol and adrenaline were lower than those found in hypoglycaemic adults. There was no relationship between the concentration of any hormone and blood glucose concentration. We postulate that hypoglycaemia and the failure to mobilise alternative fuels in some SGA infants is secondary both to a poorly coordinated counterregulatory hormone response and to a peripheral insensitivity to the actions of the hormones. Those infants, who fail to mount a counterregulatory response, should be identified by accurate and reliable blood glucose monitoring, and an adequate exogenous supply of energy, either enteral or parenteral, should be ensured.

Some neonates, such as those who are preterm or small for dates, become hypoglycaemic or hyperglycaemic. These disorders represent a failure of neonatal metabolic adaptation, but the underlying mechanisms are unclear. Data from studies of hypoglycaemic and hyperglycaemic infants were reviewed in the light of new data from studies of healthy neonates. Data from 28 neonates, who had disordered blood glucose homoeostasis, were analysed to determine the interrelationships between circulating concentrations of glucose, intermediary metabolites, glucagon and insulin, and glucose production rates. Blood glucose concentrations ranged from 2.5 to 26.1 mmol/l, and glucose production rates from 0 to 19.2 mg/kg/min. Blood glucose concentrations were positively related to intravenous glucose infusion rates and to glucose production rates. A negative relationship existed between plasma glucagon and blood glucose concentrations, but there was a wide variation in plasma insulin levels at all blood glucose concentrations. No relationship between either plasma insulin or glucagon concentration and glucose production rate was shown. It is concluded that in neonates with disordered blood glucose homoeostasis, blood glucose concentration is influenced by the rate of administration of glucose, with less precise internal control mechanisms than older subjects. This emphasises the importance of blood glucose monitoring and careful prescribing of exogenous glucose by clinicians caring for such infants.

A pilot scheme of appraisal and career counselling for senior house officers (SHOs) in the Northern region has been undertaken. There were two sets of guidelines for the conduct of these interviews, one was a list of topics and the other a modification of the Manchester rating scale. All appraisal interviews were evaluated separately by the participating SHOs and consultants. There was strong concordance between these evaluations irrespective of the format chosen. Almost all participants considered that the interviews were useful, resulted in a fair assessment of performance, and fulfilled the stated aims of the scheme.

Aims: To determine the combined effects of sudden infant death syndrome (SIDS) risk factors in the sleeping environment for infants who were “small at birth” (pre-term (

Could mediation help? The UK readership of Archives will remember October 2004 for Charlotte Wyatt1,2 and Luke Winston-Jones.3,4 Charlotte was severely disabled following complications of extreme prematurity, and Luke with trisomy 18. In each case the clinical teams believed that active, life prolonging medical interventions would not be in the best interests of the baby. The cases were brought to the civil courts because fundamental and irreconcilable differences between the families and the clinical teams came to an impasse, leaving the respective hospitals with no alternative but to seek a judicial ruling on the management of each child. Observers from other units will either feel that they have been there too, or dread the time that they may find themselves in similar situations. We should reflect constructively on these cases and be thankful that they remain rare. Most of the time, even in the most difficult situations, we are able to work alongside parents, …

An infant of 31 weeks' gestation presented with refractory neonatal hypoglycaemia secondary to islet cell dysregulation. Treatment was started with somatostatin analogue and his glycaemic control improved initially. Tolerance developed, however, in that the dose required to maintain control increased by a factor of 40. The infant subsequently underwent pancreatectomy. It is safe to use somatostatin analogue in a preterm infant, but tolerance to the drug rapidly develops.

Helpful, harmful, or don’t we know? (see pages1106 and 1111) The publication in the Lancet of the European Concerted Action on sudden infant death syndrome (SIDS) (ECAS study)1 resulted in front page headlines such as “Don’t sleep with your baby” ( Daily Telegraph : D Derbyshire, Science Correspondent, 16 January 2004). Yet the ECAS study said nothing new about bed-sharing and cot death: both the CESDI study (Confidential Enquiry into Stillbirth and Death in Infancy),2 data from New Zealand,3 and work from Ireland4 have superficially come to similar conclusions. Is the quality of evidence such that paediatricians, midwives, and health visitors should reasonably dissuade mothers from bed-sharing or co-sleeping, or is there more to it than that? First, we must question the validity of extrapolating health messages from case controlled data sets. Bradford-Hill suggested robust criteria (temporal relationship, specificity, biological plausibility, coherence; others would add dose response) for inferring causality from associative data when prospective randomised trials are impossible.5 It took some time before these criteria were satisfied to such an extent that the successful “back to sleep” campaign could be accepted as public policy. That success should not seduce us into accepting a lower standard of evidence of causality for some “new” hypothetical risk factor. Arguably, now that we have good reason to promote supine sleeping, an appropriate thermal environment, and the avoidance of cigarette smoke, the benefit of any further message on reducing the risk of SIDS is likely to be marginal at best. Second, there is a general lack of understanding about the heterogeneity of bed-sharing in particular, and infant sleep environments in general, in the data collection and analyses of case control studies. These …

The increased risk of hypoglycaemia for infants who are small for gestational age (SGA) is well known, and further information regarding metabolic adaptation can be gained by examining the profiles of glucose and other metabolic fuels in such infants. Not all SGA infants experience hypoglycaemia, however, and the ability to identify, antenatally, those at most risk would be helpful for obstetric and neonatal management. This study investigated metabolic differences between two groups of SGA infants who had antenatal umbilical artery Doppler studies. Fourteen had end diastolic velocities (EDV) present and 11 had absent EDV. The absent EDV group had significantly lower non-esterified fatty acid (NEFA) concentrations at birth, and lower blood glucose and NEFA concentrations in the first six hours after birth. After the first day, few metabolic differences were found between the two groups. Antenatal Doppler studies may identify those SGA infants who fail to achieve neonatal metabolic adaptation and are most at risk of early neonatal hypoglycaemia.

There have been few comprehensive accounts of the relationships between glucose and other metabolic fuels during the first postnatal week, especially in the context of modern feeding practises. A cross sectional study was performed of 156 term infants and 62 preterm infants to establish the normal ranges and interrelationships of blood glucose and intermediary metabolites in the first postnatal week, and to compare these with those of 52 older children. Blood glucose concentrations varied more for preterm than for term infants (1.5-12.2 mmol/l v 1.5-6.2 mmol/l), and preterm infants had low ketone body concentrations, even at low blood glucose concentrations. Breast feeding of term infants and enteral feeding of preterm infants appeared to enhance ketogenic ability. Term infants had lower prefeed blood glucose concentrations than children but, like children, appeared to be capable of producing ketone bodies. This study demonstrates that neonatal blood glucose concentrations should be considered in the context of availability of other metabolic fuels, and that the preterm infant has a limited ability to mobilise alternative fuels.

Eleven newborn babies of normal weights sustained falls onto a hard surface in hospital. The one baby who fell from >1 m sustained clinical and radiological trauma and encephalopathy, with a skull fracture and cerebral contusion. No other baby demonstrated neurological signs despite the presence of parietal skull fractures in four of six who were x rayed; only two babies had scalp swelling. The findings suggest that parietal fractures can result from very low-level falls, and scalp swelling is a poor marker for underlying fracture.