Thresholds for hypoglycaemic screening-a cause for concern?

The new Framework for Practice highlights the limited evidence for our current clinical practice (1). It is helpful in emphasising the importance of accurate measurement of glucose concentrations, listening to the concerns of parents and acknowledging that untreated hypoglycaemia can have devastating longterm consequences. However we have the following concerns: Screening thresholds The Framework recommends lowering a commonly accepted screening threshold in infants considered to be at risk of hypoglycaemia to a level that at any other time of life would be considered harmful. It fails to acknowledge the differences between screening and diagnostic thresholds; something neonatologists are very familiar with in the management of babies with jaundice. Phototherapy is provided to many babies with bilirubin levels well below a harmful level to prevent a harmful level being reached. Screening interventions are intended to prevent harmful events. Such thresholds will inevitably mean many individuals are treated ‘unnecessarily’ to avoid the risk of significant harm. In 2000 Cornblath et al published guidance on ‘operational thresholds’ in keeping with the current BAPM framework (2). However, and possibly reflecting concerns about the lack of evidence for the safety of this lower operational threshold, in 2017 in the UK, >80% of neonatal units still used <2.6mmol/ as their defined hypoglycaemic threshold (3). A threshold of <2.6mmol/l provides an opportunity for intervention before damaging neuroglycopaenia occurs

A randomised controlled trial of early insulin therapy in very low birth weight infants, "NIRTURE" (neonatal insulin replacement therapy in Europe).

BACKGROUND: Studies in adult intensive care have highlighted the importance of insulin and improved glucose control on survival, with 32% reduction in mortality, 22% reduction in intensive care stay and halving of the incidence of bacteraemia. Very low birth weight infants requiring intensive care also have relative insulin deficiency often leading to hyperglycaemia during the first week of life. The physiological influences on insulin secretion and sensitivity, and the potential importance of glucose control at this time are not well established. However there is increasing evidence that the early postnatal period is critical for pancreatic development. At this time a complex set of signals appears to influence pancreatic development and beta cell survival. This has implications both in terms of acute glucose control but also relative insulin deficiency is likely to play a role in poor postnatal growth, which has been associated with later motor and cognitive impairment, and fewer beta cells are linked to risk of type 2 diabetes later in life. METHODS: A multi-centre, randomised controlled trial of early insulin replacement in very low birth weight babies (VLBW, birth weight < 1500 g). 500 infants will be recruited from 10 centres in the UK and Europe. Babies will be randomised to receive a continuous insulin infusion (0.05 units/kg/h) or to receive standard neonatal care from the first day of life and for the next 7 days. If blood glucose (BG) levels fall infants will receive 20% dextrose titrated to maintain normoglycaemia (4-8 mmol/l). If BG is consistently above 10 mmol/l babies will receive standard treatment with additional insulin infusion. The primary end point will be mortality on or before expected date of delivery, secondary end points will be markers of morbidity and include episodes of sepsis, severity of retinopathy, chronic lung disease and growth

Neuropathologic Characterization of Pontocerebellar Hypoplasia Type 6 Associated With Cardiomyopathy and Hydrops Fetalis and Severe Multisystem Respiratory Chain Deficiency due to Novel RARS2 Mutations

Autosomal recessive mutations in the RARS2 gene encoding the mitochondrial arginyl-transfer RNA synthetase cause infantile-onset myoencephalopathy pontocerebellar hypoplasia type 6 (PCH6). We describe 2 sisters with novel compound heterozygous RARS2 mutations who presented perinatally with neurologic features typical of PCH6 but with additional features including cardiomyopathy, hydrops, and pulmonary hypoplasia and who died at 1 day and 14 days of age. Magnetic resonance imaging findings included marked cerebellar hypoplasia, gyral immaturity, punctate lesions in cerebral white matter, and unfused deep cerebral grey matter. Enzyme histochemistry of postmortem tissues revealed a near-global cytochrome c oxidase-deficiency; assessment of respiratory chain enzyme activities confirmed severe deficiencies involving complexes I, III, and IV. Molecular genetic studies revealed 2 RARS2 gene mutations: a c.1A>G, p.? variant predicted to abolish the initiator methionine, and a deep intronic c.613-3927C>T variant causing skipping of exons 6–8 in the mature RARS2 transcript. Neuropathologic investigation included low brain weights, small brainstem and cerebellum, deep cerebral white matter pathology, pontine nucleus neuron loss (in 1 sibling), and peripheral nerve pathology. Mitochondrial respiratory chain immunohistochemistry in brain tissues confirmed an absence of complexes I and IV immunoreactivity with sparing of mitochondrial numbers. These cases expand the clinical spectrum of RARS2 mutations, including antenatal features and widespread mitochondrial respiratory chain deficiencies in postmortem brain tissues

Neonatal birth fractures: a retrospective tertiary maternity hospital review

We aimed to identify the incidence and types of neonatal birth fractures in a single tertiary maternity hospital in the United Kingdom and to find possible associated factors, including all live births born between 2000 and 2016. We reviewed hospital records and imaging of all neonates who had any imaging done to identify birth fractures. We identified 87,461 consecutive live births. Sixty-six sustained a fracture during delivery: 46 clavicle-, 13 humerus-, four skull-, one femoral-, one rib- and one tibial fracture. Five neonates with a clavicle or humeral fracture had an Erb’s palsy. Sixty-five fractures were in singletons. Twenty-five fractures were diagnosed after discharge. Binary logistic regression analysis with R-Studio showed a significant association between ‘Fracture’ and ‘Birthweight’ (p < .0005), ‘Delivery Mode’ (Forceps: p < .001, Ventouse: p < .0004) and ‘Gestation’ (p < .0005) but not with ‘Sex’, ‘Day’ and ‘Time’ of delivery, ‘Number of deliveries per day’, ‘Singleton/Multiple Births’ and ‘Breech’. The incidence of birth fractures (0.075%) was low with 24 hours obstetrician support on site in comparison to published data. We recommend to include data on neonatal birth injuries in addition to the existing clinical safety markers for delivery units.Impact statement What is already known on this subject? Most birth fractures affect the clavicle with a large variation in published incidences from 0.035% to 3.2%. High birthweight is the most frequently identified risk factor. An increased risk for out of hours deliveries (16.00–8.00) and inverse association between fracture rate and level of experience and academic qualification have also been reported. Between 14% and 39% of fractures are diagnosed after discharge but many studies are based on birth certificate and discharge diagnoses coding only. What the results of this study add? This is the first study on neonatal birth fractures from the United Kingdom and the only study for which radiological investigations of all neonates were reviewed. Our fracture rate of 0.075% for all fractures is therefore most likely the most accurate, showing no significant difference in the fracture risk between our six defined time intervals and days of the week, with experienced midwifes managing many high risk pregnancies and an obstetrician being present on site all the time. What the implications are of these findings for clinical practice and/or further research? Our findings support to use data on neonatal birth injuries as one indicator to assess the quality and safety of maternity units