Continuous glucose monitoring in newborn babies at risk of hypoglycemia

Relationship between EEG spectral power and dysglycemia with neurodevelopmental outcomes after neonatal encephalopathy

OBJECTIVE

We investigated how electroencephalography (EEG) quantitative measures and dysglycemia relate to neurodevelopmental outcomes following neonatal encephalopathy (NE).

METHODS

This retrospective study included 90 neonates with encephalopathy who received therapeutic hypothermia. EEG absolute spectral power was calculated during post-rewarming and 2-month follow-up. Measures of dysglycemia (hypoglycemia, hyperglycemia, and glycemic lability) and glucose variability were computed for the first 48 h of life. We evaluated the ability of EEG and glucose measures to predict neurodevelopmental outcomes at ≥ 18 months, using logistic regressions (with area under the receiver operating characteristic [AUROC] curves).

RESULTS

The post-rewarming global delta power (average all electrodes), hyperglycemia and glycemic lability predicted moderate/severe neurodevelopmental outcome separately (AUROC = 0.8, 95%CI [0.7,0.9], p < .001) and even more so when combined (AUROC = 0.9, 95%CI [0.8,0.9], p < .001). After adjusting for NE severity and magnetic resonance imaging (MRI) brain injury, only global delta power remained significantly associated with moderate/severe neurodevelopmental outcome (odds ratio [OR] = 0.9, 95%CI [0.8,1.0], p = .04), gross motor delay (OR = 0.9, 95%CI [0.8,1.0], p = .04), global developmental delay (OR = 0.9, 95%CI [0.8,1.0], p = .04), and auditory deficits (OR = 0.9, 95%CI [0.8,1.0], p = .03).

CONCLUSIONS

In NE, global delta power post-rewarming was predictive of outcomes at ≥ 18 months.

SIGNIFICANCE

EEG markers post-rewarming can aid prediction of neurodevelopmental outcomes following NE.

Neonatal hypoglycaemia

Low blood concentrations of glucose (hypoglycaemia) soon after birth are common because of the delayed metabolic transition from maternal to endogenous neonatal sources of glucose. Because glucose is the main energy source for the brain, severe hypoglycaemia can cause neuroglycopenia (inadequate supply of glucose to the brain) and, if severe, permanent brain injury. Routine screening of infants at risk and treatment when hypoglycaemia is detected are therefore widely recommended. Robust evidence to support most aspects of management is lacking, however, including the appropriate threshold for diagnosis and optimal monitoring. Treatment is usually initially more feeding, with buccal dextrose gel, followed by intravenous dextrose. In infants at risk, developmental outcomes after mild hypoglycaemia seem to be worse than in those who do not develop hypoglycaemia, but the reasons for these observations are uncertain. Here, the current understanding of the pathophysiology of neonatal hypoglycaemia and recent evidence regarding its diagnosis, management, and outcomes are reviewed. Recommendations are made for further research priorities.

Investigating behaviour from early- to mid-childhood and its association with academic outcomes in a cohort of children born at risk of neonatal hypoglycaemia

High rates of academic underachievement at 9-10 years have been identified in children born at risk of neonatal hypoglycaemia. This study investigated the stability of behaviour from early to mid-childhood and how this relates to academic outcomes in children born with at least one risk factor of neonatal hypoglycaemia in Aotearoa, New Zealand. Behaviour data was collected using the Bayley Scales of Infant and Toddler Development, Child Behaviour Checklist 1.5-5, and the Strengths and Difficulties Questionnaire for 466 children (52 % male; 27 % Māori, 60 % New Zealand European, 2 % Pacific, 11 % Other) at multiple timepoints between ages 2 and 10 years. Academic data was collected at 9-10 years using the e-asTTle online learning and assessment tool. Findings revealed a link between early childhood behaviour and academic outcomes could be detected as early as age 2, suggesting that identifying and addressing early behavioural issues in children at risk of neonatal hypoglycaemia could aid in targeted interventions.

Continuous interstitial glucose monitoring for term newborns: analysis of the first day of life

OBJECTIVE

Glycaemia in newborns changes significantly after birth; however, little is known about these changes. The objective was to describe continuous interstitial glucose values in term newborns who were exclusively breast fed on the first day of life.

DESIGN

We studied 159 newborns with appropriate weights for gestational age, who were exclusively breast fed on the first day of life, using a continuous glucose monitoring device that calculates interstitial glucose every 5 min. The device was removed after 24 hours, and the results were analysed using the R program, which provides the minimum, maximum, median and a standard curve with centiles.

RESULTS

At the second hour of life, the moment in which the sensor started to identify the newborn's glycaemia, interstitial glucose levels were 2.59-4.43 mmol/L (46.7-79.9 mg/dL). The median interstitial glucose level of the newborns during the first day of life was 3.33±0.48 mmol/L (60±8.6 mg/dL). Interstitial glucose levels dropped until the sixth hour of life, reaching 2.19-3.95 mmol/L (39.5-71.1 mg/dL), and then increased again. The maximum values were found at the 20th and 21st hours of life, which were 2.81-4.64 mmol/L (50.6-83.6 mg/dL).

CONCLUSION

The interstitial glucose during the first 24 hours of life declined until the sixth hour of life, then increased around the 20th hour and remained stable until the end of the first day of life.

Stability of executive function in children born at risk of neonatal hypoglycemia

Executive function plays an important role in promoting learning and social-emotional development in children. Neonatal hypoglycemia associates with executive function difficulties at 4.5 years, but little is known about the development of executive function over time in children born at risk of neonatal hypoglycemia. We aimed to describe the stability of executive function from early to mid-childhood in children born at risk of neonatal hypoglycemia and its association with neonatal hypoglycemia. Participants in a prospective cohort study of infants born at risk for neonatal hypoglycemia were assessed at ages 2, 4.5, and 9-10 years. We assessed executive function with batteries of performance-based and questionnaire-based measures, and classified children into one of four stability groups (persistent typical, intermittent typical, intermittent difficulty, and persistent difficulty) based on dichotomized scores (typical versus low at each age). Multinomial logistic regression was used to determine the associations between neonatal hypoglycemia and executive function stability groups. Three hundred and nine children, of whom 197 (64%) experienced neonatal hypoglycemia were assessed. The majority of children had stable and typical performance-based (63%) and questionnaire-based (68%) executive function across all three ages. Around one-third (30-36%) of children had transient difficulties, and only a few (0.3-1.9%) showed persistent difficulties in executive function at all ages. There was no consistent evidence of an association between neonatal hypoglycemia and the stability of executive function. Neonatal hypoglycemia does not appear to predict a specific pattern of development of executive function in children born at risk.

Continuous Glucose Monitoring: A Possible Aid for Detecting Hypoglycemic Events during Insulin Tolerance Tests

The combined pituitary function test evaluates the anterior pituitary gland, while the insulin tolerance test evaluates growth hormone deficiencies. However, successful stimulation requires achieving an appropriate level of hypoglycemia. Close medical supervision for glucose monitoring is required during hypoglycemia induction and the test is often very tedious. In addition, a capillary blood sugar test (BST) and serum glucose levels may differ greatly. An alternative approach may be utilizing a continuous glucose-monitoring (CGM) system. We provide three cases in which CGM was successfully used alongside a standard BST and serum glucose levels during the combined pituitary function test to better detect and induce hypoglycemia. Three participants who were diagnosed with multiple pituitary hormone deficiencies during childhood were re-evaluated in adulthood; a Dexcom G6 CGM was used. The CGM sensor glucose and BST levels were simultaneously assessed for glycemic changes and when adequate hypoglycemia was reached during the combined pituitary function test. The CGM sensor glucose, BST, and serum glucose levels showed similar glucose trends in all three patients. A Bland-Altman analysis revealed that the CGM underestimated the BST values by approximately 9.68 mg/dL, and a Wilcoxon signed-rank test showed that the CGM and BST measurements significantly differed during the stimulation test (p = 0.003). Nevertheless, in all three cases, the CGM sensor mimicked the glycemic variability changes in the BST reading and assisted in monitoring appropriate hypoglycemia nadir. Thus, CGM can be used as a safe aid for clinicians to use during insulin tolerance tests where critical hypoglycemia is induced.

Size at birth predicts later brain volumes

We aimed to investigate whether gestation at birth, birth weight, and head circumference at birth are still associated with brain volume and white matter microstructure at 9-10 years in children born late-preterm and at term. One hundred and eleven children born at ≥ 36 weeks gestation from the CHYLD Study cohort underwent brain magnetic resonance imaging at 9 to 10 years. Images were analysed using FreeSurfer for volumetric data and tract-based spatial statistics for diffusion data. Of the cohort, 101 children were included for volumetric analysis [boys, 49(49%); median age, 9.5 (range: 8.9-12.4) years]. Shorter gestation at birth, lower birthweight, and smaller birth head circumference were associated with smaller brain volumes at 9 to 10 years, both globally and regionally. Amongst the perinatal factors studied, head circumference at birth was the strongest predictor of later brain volumes. Gestation at birth and absolute birthweight were not associated with diffusion metrics of white matter skeleton. However, lower birthweight z-score was associated with higher fractional anisotropy and lower radial diffusivity. Our findings suggest that even in children born late preterm and at term, growth before birth and timing of birth are still associated with brain development in mid-childhood.

Continuous Glucose Monitoring in Transient Neonatal Diabetes Mellitus-2 Case Reports and Literature Review

Neonatal diabetes mellitus is a rare genetic disease that affects 1 in 90,000 live births. The start of the disease is often before the baby is 6 months old, with rare cases of onset between 6 months and 1 year. It is characterized by low or absent insulin levels in the blood, leading to severe hyperglycemia in the patient, which requires temporary insulin therapy in around 50% of cases or permanent insulin therapy in other cases. Two major processes involved in diabetes mellitus are a deformed pancreas with altered insulin-secreting cell development and/or survival or faulty functioning of the existing pancreatic beta cell. We will discuss the cases of two preterm girls with neonatal diabetes mellitus in this research. In addition to reviewing the literature on the topic, we examined the different mutations, patient care, and clinical outcomes both before and after insulin treatment.

Screening and diagnosis of neonatal hypoglycaemia in at-risk late preterm and term infants following AAP recommendations: a single centre retrospective study

BACKGROUND

There is a lack of consensus regarding the definition and treatment threshold for neonatal hypoglycaemia. The American Academy of Pediatrics (AAP) has a published clinical report making recommendations on practice guidelines. There is limited literature discussing the impact of these guidelines. In this study, we evaluated the screening and diagnosis of neonatal hypoglycaemia following the AAP guidelines.

METHODS

Infants born ≥35 weeks gestational age and admitted to the well-baby nursery between January and December 2017 were included in this study. Our hypoglycaemia policy was based on the AAP clinical report for hypoglycaemia management in newborns. Chart review was done to obtain infant hypoglycaemia risk factors and blood glucose values in the first 24 hours. Data analysis was conducted using Stata V.14.2 (StataCorp).

RESULTS

Of 2873 infants born and admitted to the well-baby nursery, 32% had at least one hypoglycaemia risk factor and 96% of them were screened for hypoglycaemia. Screened infants were more likely to be born at a lower gestational age, via C-section, and to a multiparous older mother. Screened infants and hypoglycaemic infants had lower exclusive breastfeeding rates compared with those who were not screened or not hypoglycaemic, respectively. Sixteen per cent of screened infants were diagnosed with hypoglycaemia; 0.8% of at-risk screened infants and 5% of hypoglycaemic infants were admitted to the NICU for treatment of hypoglycaemia. Thirty-one per cent of preterm infants, 15% of large for gestational age infants, 13% of small for gestational age infants and 15% of infants of diabetic mothers were hypoglycaemic. Hypoglycaemic infants were more likely to be born preterm and via C-section.

CONCLUSION

Using the AAP time-based definitional blood glucose cut-off values, our incidence of hypoglycaemia found in those who were screened for risk factors was lower compared with other studies. Future long-term follow-up studies will be important.

Relationships between feeding and glucose concentrations in healthy term infants during the first five days after birth-the Glucose in Well Babies Study (GLOW)

Background

The World Health Organization recommends breastfeeding be commenced as soon as possible after birth. Amongst other benefits, early feeding is expected to support the metabolic transition after birth, but effects on blood glucose concentrations are controversial. We sought to describe the changes in interstitial glucose concentrations after feedings over the first five postnatal days.

Participants and Methods

In healthy singleton term infants, all feeds were recorded using a smart phone app. Glucose concentrations were measured by blinded interstitial monitoring, calibrated by heel-prick capillary samples 2-4 times/d. Feeding sessions were included if a start and end time were recorded, and if the interval between the start of successive feeds was >90 min. The area under the glucose concentration curve (AUC) was calculated by trapezoidal addition from baseline (median of the 3 measurements before the beginning of the session). The maximum deviation (MD) was the greatest change in glucose concentration (positive or negative) from baseline to the next feeding session or 180 min, whichever came first. Data were analyzed using Stata V17 and are presented as mean (95% CI) in mmol/L.

Results

Data were available for 62 infants and 1,770 feedings. The glucose response to breastfeeding was not different from zero on day 1 [day 1 AUC 0.05 (-0.00, 0.10), MD 0.06 (-0.05, 0.16)], but increased thereafter (day 3 (AUC 0.23 (0.18, 0.28), MD 0.41 (0.32, 0.50), day 5 AUC 0.11 (0.06, 0.16), MD 0.28 (0.18, 0.37), p < 0.001 for age effect). Glucose response increased with increased duration of breastfeeding (<30 min AUC 0.06 (0.02,0.09), MD 0.12 (0.04,0.19), >30 min AUC 0.20 (0.16, 0.23) MD 0.37 (0.30, 0.44), p < 0.001 for duration effect) and this was observed even in the first 2 days (<30 min AUC-0.02 (-0.06, 0.03), MD -0.06 (-0.15, 0.03), >30 min AUC 0.12 (0.08, 0.16), MD 0.19 (0.11, 0.27), overall p < 0.001 for age x duration interaction). In feeding sessions that were not breastfeeding, the glucose response was greater after formula than after expressed human milk [AUC 0.29 (0.15, 0.29), MD 0.48 (-0.12, 0.61)], and greater after feed volumes >20 ml than <10 ml [20-30 ml AUC 0.19 (0.01, 0.27), MD 0.23 (-0.01, 0.46)].

Conclusion

The glucose response to feeding in the days after birth increases with postnatal age and duration of the feeding episode. Breastfeeding for <30 min has little effect on glucose concentrations in the first two days.

Neurodevelopmental correlates of caudate volume in children born at risk of neonatal hypoglycaemia

BACKGROUND

Neonatal hypoglycaemia can lead to brain damage and neurocognitive impairment. Neonatal hypoglycaemia is associated with smaller caudate volume in the mid-childhood. We investigated the relationship between neurodevelopmental outcomes and caudate volume and whether this relationship was influenced by neonatal hypoglycaemia.

METHODS

Children born at risk of neonatal hypoglycaemia ≥36 weeks' gestation who participated in a prospective cohort study underwent neurodevelopmental assessment (executive function, academic achievement, and emotional-behavioural regulation) and MRI at age 9-10 years. Neonatal hypoglycaemia was defined as at least one hypoglycaemic episode (blood glucose concentration <2.6 mmol/L or at least 10 min of interstitial glucose concentrations <2.6 mmol/L). Caudate volume was computed using FreeSurfer.

RESULTS

There were 101 children with MRI and neurodevelopmental data available, of whom 70 had experienced neonatal hypoglycaemia. Smaller caudate volume was associated with greater parent-reported emotional and behavioural difficulties, and poorer prosocial behaviour. Caudate volume was significantly associated with visual memory only in children who had not experienced neonatal hypoglycaemia (interaction p = 0.03), but there were no other significant interactions between caudate volume and neonatal hypoglycaemia.

CONCLUSION

Smaller caudate volume is associated with emotional behaviour difficulties in the mid-childhood. Although neonatal hypoglycaemia is associated with smaller caudate volume, this appears not to contribute to clinically relevant neurodevelopmental deficits.

IMPACT

At 9-10 years of age, caudate volume was inversely associated with emotional-behavioural difficulties and positively associated with prosocial behaviour but was not related to executive function or educational achievement. Previous studies have suggested that neonatal hypoglycaemia may contribute to smaller caudate volume but exposure to neonatal hypoglycaemia did not appear to influence the relationship between caudate volume and behaviour. Among children not exposed to neonatal hypoglycaemia, caudate volume was also positively associated with visual memory, but no such association was detected among those exposed to neonatal hypoglycaemia. Understanding early-life factors that affect caudate development may provide targets for improving behavioural function.

Continuous Glucose Monitoring in Preterm Infants: The Role of Nutritional Management in Minimizing Glycemic Variability

Glycemic variability (GV) is common in preterm infants. In the premature population, GV is a risk factor for morbidity and mortality. Both hypo- and hyperglycemia can impair neurodevelopment. We investigated the impact of continuous versus intermittent tube enteral feeding on GV. In our prospective observational study, 20 preterm infants with a gestational age ≤ 34 weeks at either continuous or intermittent bolus full enteral feeding. For five days, continuous glucose monitoring (CGM) was utilized, which was achieved through the subcutaneous insertion of a sensor. A total of 27,532 measurements of blood glucose were taken. The mean amplitude of glycemic excursions did not differ between the two cohorts statistically. Continuous feeding resulted in higher positive values, increasing the risk of hypo- and hyperglycemia. Subjects who were small for their gestational age had a higher standard deviation during continuous feeding (p = 0.001). Data suggest that intermittent bolus nutrition is better for glycemic control than continuous nutrition. Nutritional management optimization of preterm infants appears to be critical for long-term health. In the future, CGM may provide a better understanding of the optimal glucose targets for various clinical conditions, allowing for a more personalized approach to management.

Feasibility and Safety of Continuous Glucose Monitoring in Infants at Risk of Hypoglycemia in a Rooming-in Setting

Background:Screening of neonatal hypoglycemia uses currently intermittent blood sampling. Continuous glucose monitoring (CGM) allows for tighter glucose control and better comfort for newborns and parents. CGM has previously been used in intensive care setting or blinded to clinicians. Our pilot study uses CGM in real time in rooming-in setting. Methods: CGM was attached within first two hours of life. Low glucose readings were verified to prevent overtreatment. Pairs of sensor readings and corresponding blood glucose measurements were assessed retrospectively. Neurodevelopmental evaluation was performed at 24 months. Results: 44 infants were enrolled. Three had verified hypoglycemia found due to CGM. No patient was below 2 standard deviations in any components of Bayley scales. Median scores were: Cognitive 100, language 86, motor 94. Conclusion: Use of CGM in a rooming-in environment is safe from clinical and neurodevelopmental point of view. Randomized trials are needed to evaluate superiority in longer term outcomes.

Cerebral Effects of Neonatal Dysglycemia

This article summarizes the available evidence reporting the relationship between perinatal dysglycemia and long-term neurodevelopment. We review the physiology of perinatal glucose metabolism and discuss the controversies surrounding definitions of perinatal dysglycemia. We briefly review the epidemiology of hypoglycemia and hyperglycemia in fetal, preterm, and term infants. We discuss potential pathophysiologic mechanisms contributing to dysglycemia and its effect on neurodevelopment. We highlight current strategies to prevent and treat dysglycemia in the context of neurodevelopmental outcomes. Finally, we discuss areas of future research and the potential role of continuous glucose monitoring.

Variations in New Zealand and Australian guidelines for the management of neonatal hypoglycaemia: A secondary analysis from the hypoglycaemia Prevention with Oral Dextrose gel Trial (hPOD)

AIM

We observed wide variation in the management of babies at risk of hypoglycaemia who participated in the hPOD (hypoglycaemia Prevention with Oral Dextrose gel) multicentre trial of prophylactic dextrose gel. The aim of this study was to identify whether this may be due to variations in the clinical guidelines used by participating hospitals.

METHODS

Guidelines for management of neonatal hypoglycaemia used by participating hospitals were reviewed. Recommendations regarding definition, risk factors, monitoring and treatment were compared between countries, hospital type (tertiary or secondary) and neonatal intensive care unit size (≤12 cots and >12 cots).

RESULTS

The 18 hospitals used 20 guidelines. The recommended diagnostic threshold for hypoglycaemia ranged from <2.0 mmol/L to <2.6 mmol/L, and glucose oxidase method of testing was recommended in seven (47%) of 15 guidelines. There was broad agreement about which infants should be monitored. Oral dextrose was the recommended first line of treatment in 17 of 20 guidelines, but the glucose threshold at which this should be used varied (≤2.6 mmol/L in New Zealand, 1.5-2.6 mmol/L in Australia). Re-checking blood glucose concentrations after oral dextrose was recommended at 30 min in most (10/11, 91%) New Zealand guidelines but at 60 min in most (4/6, 67%) Australian guidelines. There was greatest variation in recommended thresholds for referral to paediatric services or neonatal intensive care unit, and administration of intravenous dextrose. There were no significant differences between guidelines used by tertiary and secondary hospitals, or large and small hospitals.

CONCLUSION

There is wide variation in guideline recommendations for the management of neonatal hypoglycaemia across New Zealand and Australian neonatal units.

Association of Neonatal Hypoglycemia With Academic Performance in Mid-Childhood

IMPORTANCE

Neonatal hypoglycemia is associated with increased risk of poor executive and visual-motor function, but implications for later learning are uncertain.

OBJECTIVE

To test the hypothesis that neonatal hypoglycemia is associated with educational performance at age 9 to 10 years.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study of moderate to late preterm and term infants born at risk of hypoglycemia. Blood and masked interstitial sensor glucose concentrations were measured for up to 7 days. Infants with hypoglycemic episodes (blood glucose concentration <47 mg/dL [2.6 mmol/L]) were treated to maintain a blood glucose concentration of at least 47 mg/dL. Six hundred fourteen infants were recruited at Waikato Hospital, Hamilton, New Zealand, in 2006-2010; 480 were assessed at age 9 to 10 years in 2016-2020.

EXPOSURES

Hypoglycemia was defined as at least 1 hypoglycemic event, representing the sum of nonconcurrent hypoglycemic and interstitial episodes (sensor glucose concentration <47 mg/dL for ≥10 minutes) more than 20 minutes apart.

MAIN OUTCOMES AND MEASURES

The primary outcome was low educational achievement, defined as performing below or well below the normative curriculum level in standardized tests of reading comprehension or mathematics. There were 47 secondary outcomes related to executive function, visual-motor function, psychosocial adaptation, and general health.

RESULTS

Of 587 eligible children (230 [48%] female), 480 (82%) were assessed at a mean age of 9.4 (SD, 0.3) years. Children who were and were not exposed to neonatal hypoglycemia did not significantly differ on rates of low educational achievement (138/304 [47%] vs 82/176 [48%], respectively; adjusted risk difference, -2% [95% CI, -11% to 8%]; adjusted relative risk, 0.95 [95% CI, 0.78-1.15]). Children who were exposed to neonatal hypoglycemia, compared with those not exposed, were significantly less likely to be rated by teachers as being below or well below the curriculum level for reading (68/281 [24%] vs 49/157 [31%], respectively; adjusted risk difference, -9% [95% CI, -17% to -1%]; adjusted relative risk, 0.72 [95% CI, 0.53-0.99; P = .04]). Groups were not significantly different for other secondary end points.

CONCLUSIONS AND RELEVANCE

Among participants at risk of neonatal hypoglycemia who were screened and treated if needed, exposure to neonatal hypoglycemia compared with no such exposure was not significantly associated with lower educational achievement in mid-childhood.

Associations between neonatal hypoglycaemia and brain volumes, cortical thickness and white matter microstructure in mid-childhood: An MRI study

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Neonatal hypoglycaemia is associated with damage to the brain in the acute phase.

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In mid-childhood, neonatal hypoglycaemia is associated with smaller brain regions.

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Deep grey matter regions such as the caudate and thalamus are implicated.

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Children with neonatal hypoglycemia had smaller occipital lobe cortical thickness.

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Grey matter may be especially vulnerable to long-term effects of neonatal hypoglycemia.

Neonatal hypoglycaemia is a common metabolic disorder that may cause brain damage, most visible in parieto-occipital regions on MRI in the acute phase. However, the long term effects of neonatal hypoglycaemia on the brain are not well understood. We investigated the association between neonatal hypoglycaemia and brain volumes, cortical thickness and white matter microstructure at 9–10 years.

Children born at risk of neonatal hypoglycaemia at ≥ 36 weeks’ gestation who took part in a prospective cohort study underwent brain MRI at 9–10 years. Neonatal hypoglycaemia was defined as at least one hypoglycaemic episode (at least one consecutive blood glucose concentration < 2.6 mmol/L) or interstitial episode (at least 10 min of interstitial glucose concentrations < 2.6 mmol/L). Brain volumes and cortical thickness were computed using Freesurfer. White matter microstructure was assessed using tract-based spatial statistics.

Children who had (n = 75) and had not (n = 26) experienced neonatal hypoglycaemia had similar combined parietal and occipital lobe volumes and no differences in white matter microstructure at nine years of age. However, those who had experienced neonatal hypoglycaemia had smaller caudate volumes (mean difference: −557 mm³, 95% confidence interval (CI), −933 to −182, p = 0.004) and smaller thalamus (−0.03%, 95%CI, −0.06 to 0.00; p = 0.05) and subcortical grey matter (−0.10%, 95%CI −0.20 to 0.00, p = 0.05) volumes as percentage of total brain volume, and thinner occipital lobe cortex (−0.05 mm, 95%CI −0.10 to 0.00, p = 0.05) than those who had not. The finding of smaller caudate volumes after neonatal hypoglycaemia was consistent across analyses of pre-specified severity groups, clinically detected hypoglycaemic episodes, and severity and frequency of hypoglycaemic events.

Neonatal hypoglycaemia is associated with smaller deep grey matter brain regions and thinner occipital lobe cortex but not altered white matter microstructure in mid-childhood.

Continuous Glucose Monitoring in the Management of Neonates With Persistent Hypoglycemia and Congenital Hyperinsulinism

BACKGROUND

Persistent hypoglycemia is common in the newborn and is associated with poor neurodevelopmental outcome. Adequate monitoring is critical in prevention, but is dependent on frequent, often hourly blood sampling. Continuous glucose monitoring (CGM) is increasingly being used in children with type 1 diabetes mellitus, but use in neonatology remains limited. We aimed to introduce real-time CGM to provide insights into patterns of dysglycemia and to support the management of persistent neonatal hypoglycemia.

METHODS

This is a single-center retrospective study of real-time CGM use over a 4-year period in babies with persistent hypoglycemia.

RESULTS

CGMs were inserted in 14 babies: 8 term and 6 preterm infants, 9 with evidence of congenital hyperinsulinism (CHI). A total of 224 days of data was collected demonstrating marked fluctuations in glucose levels in babies with CHI, with a higher sensor glucose SD (1.52 ± 0.79 mmol/L vs 0.77 ± 0.22 mmol/L) in infants with CHI compared with preterm infants. A total of 1254 paired glucose values (CGM and blood) were compared and gave a mean absolute relative difference of 11%.

CONCLUSION

CGM highlighted the challenges of preventing hypoglycemia in these babies when using intermittent blood glucose levels alone, and the potential application of CGM as an adjunct to clinical care.

How Much Glucose Is in the Gel Used to Treat Neonatal Hypoglycemia?

OBJECTIVE

To compare glucose concentrations in three sections of individual tubes and among tubes of commercial oral glucose gels commonly used to treat neonatal hypoglycemia in the United States (Glutose 15 [Perrigo, Minneapolis, MN] and Insta-Glucose [Valeant Pharmaceuticals North America LLC, Bridgewater, NJ]).

DESIGN

A quantitative laboratory study.

METHODS

We measured glucose concentrations in aliquots taken from the top, middle, and bottom sections of three different lots and in whole tubes from different lots of Glutose 15 and Insta-Glucose. We measured the glucose content in the gel using hexokinase and glucose-6-phosphate dehydrogenase enzymes on the Siemens ADVIA 1800 analyzer (Siemens Healthcare Diagnostics, Inc., Tarrytown, NY).

RESULTS

The percent difference observed among the three sections of the Glutose 15 tubes was 12.3% to 53.8%. The difference among the three sections of the Insta-Glucose tubes was 40.7% to 79.6%. The concentration of glucose gel is labeled as 40%, but the actual concentration in aliquots of Glutose 15 ranged from 39.64% to 70.96%. The actual concentration in aliquots of Insta-Glucose ranged from 16.45% to 27.47%. The difference in the concentration of glucose among three lots of whole tubes of Glutose 15 was 1.6%, and the difference in concentration among three lots of whole tubes of Insta-Glucose was 8.8%. In Glutose 15, the concentration ranged from 48.3% to 49.1%, and Insta-Glucose, the concentration ranged from 17.2% to 18.8%.

CONCLUSION

Glucose was not uniformly distributed within tubes of Glutose 15 and Insta-Glucose, and this may account for variable results on the efficacy of oral glucose gel as a treatment for neonatal hypoglycemia.

Nutrition and management of glycemia in neonates with neonatal encephalopathy treated with hypothermia

Adequate nutrition and glycemic homeostasis are increasingly recognized as potentially neuroprotective for the developing brain. In the context of hypoxia-ischemia, evidence is scarce regarding optimal nutritional support and administration route, as well as the short- and long-term consequences of such interventions. In this review, we summarize current knowledge on disturbances of brain metabolism of glucose and substrates by hypoxia-ischemia, and compound effects of these mechanisms on brain injury characterized by specific patterns on EEG and MRI. Risks and benefits of nutrition delivery via parenteral or enteral routes are examined. Nutrition could mitigate adverse neurodevelopmental outcomes, and the impact of nutritional strategies and specific nutritional interventions are reviewed. Limited literature highlights the need for further studies to understand the changes in energy metabolism during and after hypoxic-ischemic injury, to optimize nutritional regimens and glucose management, and to inform the neuroprotective role of nutrition.

Effect of Prophylactic Dextrose Gel on Continuous Measures of Neonatal Glycemia: Secondary Analysis of the Pre-hPOD Trial

OBJECTIVE

To determine the effects of different doses of prophylactic dextrose gel on glycemic stability assessed using continuous glucose monitoring in the first 48 hours when given to babies at risk of neonatal hypoglycemia.

STUDY DESIGN

Continuous glucose monitoring was undertaken for the first 48 hours in 133 infants at risk of hypoglycemia who participated in the pre-hPOD randomized dosage trial of dextrose gel prophylaxis.

RESULTS

Low glucose concentrations were detected in 41% of infants by blood glucose monitoring and 68% by continuous interstitial glucose monitoring. The mean ± SD duration of low interstitial glucose concentrations was 295 ± 351 minutes in the first 48 hours. Infants who received any dose of dextrose gel seemed to be less likely than those who received placebo gel to experience low glucose concentrations (<47 mg/dL [2.6 mmol/L]; P = .08), particularly if they received a single dose of 200 mg/kg (relative risk, 0.70; 95% CI, 0.50-0.10; P = .049). They also spent a greater proportion of time in the central glucose concentration range of 54-72 mg/dL (3-4 mmol/L) (any dose, mean ± SD, 58.2 ± 20.3%; placebo, 50.0 ± 21.9%; mean difference, 8.20%; 95% CI, 0.43-15.9%; P = .038). Dextrose gel did not increase recurrent or severe episodes of low glucose concentrations and did not increase the peak glucose concentration. These effects were similar for all trial dosages.

CONCLUSIONS

Low glucose concentrations were common in infants at risk of hypoglycemia despite blood glucose monitoring and treatment. Prophylactic dextrose gel reduced the risk of hypoglycemia without adverse effects on glucose stability.

The Term Newborn: Hypoglycemia

This review provides an update on neonatal hypoglycemia in the term infant, including discussion of glucose metabolism, definitions of hypoglycemia, identification of infants commonly at risk, and the screening, treatment, and potential neurologic outcomes of postnatal hypoglycemia. Neonatal hypoglycemia is a common metabolic condition that continues to plague clinicians because there is no clear relationship between low glucose concentrations or their duration that determines adverse neurologic outcomes. However, severely low, prolonged, recurrent low glucose concentrations in infants who also have marked symptoms such as seizures, flaccid hypotonia with apnea, and coma clearly are associated with permanent brain damage. Early identification of at-risk infants, early and continued breastfeeding augmented with oral dextrose gel, monitoring prefeed glucose concentrations, treating symptomatic infants who have very low and recurrent low glucose concentrations, and identifying and aggressively managing infants with persistent hyperinsulinemia and metabolic defects may help prevent neuronal injury.

Strategies to improve neurodevelopmental outcomes in babies at risk of neonatal hypoglycaemia

Neonatal hypoglycaemia is associated with adverse development, particularly visual-motor and executive function impairment, in childhood. As neonatal hypoglycaemia is common and frequently asymptomatic in at-risk babies-ie, those born preterm, small or large for gestational age, or to mothers with diabetes, it is recommended that these babies are screened for hypoglycaemia in the first 1-2 days after birth with frequent blood glucose measurements. Neonatal hypoglycaemia can be prevented and treated with buccal dextrose gel, and it is also common to treat babies with hypoglycaemia with infant formula and intravenous dextrose. However, it is uncertain if screening, prophylaxis, or treatment improves long-term outcomes of babies at risk of neonatal hypoglycaemia. This narrative review assesses the latest evidence for screening, prophylaxis, and treatment of neonates at risk of hypoglycaemia to improve long-term neurodevelopmental outcomes.

Practice Variations in Diagnosis and Treatment of Hypoglycemia in Asymptomatic Newborns

OBJECTIVES

To describe variations in the practice of hypoglycemia screening and treatment in asymptomatic infants in the United States.

METHODS

During the time period from February 2018 to June 2018, we surveyed representatives of hospitals participating in the Better Outcomes through Research for Newborns Network, a national research network of clinicians providing hospital care to term and late-preterm newborns. The survey included 22 questions evaluating practices related to hypoglycemia screening and management of asymptomatic infants.

RESULTS

Of 108 network sites, 84 (78%) responded to the survey; 100% had a hypoglycemia protocol for screening at-risk infants in the well-baby nursery. There were wide variations between sites regarding the definition of hypoglycemia (mg/dL) (<45 [24%]; <40 [23%]; <40 [0-4 hours] and <45 [4-24 hours] [27%]; <25 [0-4 hours] and <35 [4-24 hours] [8%]), timing of first glucose check (<1 hour [18%], 1-2 hours [30%], 30 minutes post feed [48%]), and threshold glucose level for treatment (<45 [19%]; <40 [18%]; <40 [0-4 hours] and <45 [4-24 hours] [20%]; <25 [0-4 hours] and <35 [4-24 hours] [15%]). All respondents used breast milk as a component of initial therapy. Criteria for admission to the NICU for hypoglycemia included the need for dextrose containing intravenous fluids (52%), persistent hypoglycemia despite treatment (49%), and hypoglycemia below a certain value (37%).

CONCLUSIONS

There is a significant practice variation in hypoglycemia screening and management across the United States.

Two-year outcomes after dextrose gel prophylaxis for neonatal hypoglycaemia

OBJECTIVE

To determine the effect of prophylactic dextrose gel for prevention of neonatal hypoglycaemia on neurodevelopment and executive function at 2 years' corrected age.

DESIGN

Prospective follow-up of a randomised trial.

SETTING

New Zealand.

PATIENTS

Participants from the pre-hypoglycaemia Prevention with Oral Dextrose (pre-hPOD) trial randomised to one of four dose regimes of buccal 40% dextrose gel or equivolume placebo.

MAIN OUTCOME MEASURES

Coprimary outcomes were neurosensory impairment and executive function. Secondary outcomes were components of the primary outcomes, neurology, anthropometry and health measures.

RESULTS

We assessed 360 of 401 eligible children (90%) at 2 years' corrected age. There were no differences between dextrose gel dose groups, single or multiple dose groups, or any dextrose and any placebo groups in the risk of neurosensory impairment or low executive function (any dextrose vs any placebo neurosensory impairment: relative risk (RR) 0.77, 95% CI 0.50 to 1.19, p=0.23; low executive function: RR 0.50, 95% CI 0.24 to 1.06, p=0.07). There were also no differences between groups in any secondary outcomes. There was no difference between children who did or did not develop neonatal hypoglycaemia in the risk of neurosensory impairment (RR 1.05, 95% CI 0.68 to 1.64, p=0.81) or low executive function (RR 0.73, 95% CI 0.34 to 1.59, p=0.43).

CONCLUSION

Prophylactic dextrose gel did not alter neurodevelopment or executive function and had no adverse effects to 2 years' corrected age, but this study was underpowered to detect potentially clinically important effects on neurosensory outcomes.

Monitoring the Frequency and Duration of Hypoglycemia in Preterm Infants and Identifying Associated Factors

Hypoglycemia is common in very low birth weight neonates and may have adverse effects. Material and Method: Sixty preterm infants were monitored using continuous glucose monitoring (CGMS) and capillary techniques during the first week of life. Hypoglycemia was defined as glucose ≤47 mg/dL (≤2.6 mmol/L). Results: Hypoglycemic episodes were detected in 41.66% (95% CI: 29.07-55.12). In 69.64% the duration was greater than thirty minutes, in 26.78% (95% CI: 15.83-40.3) hypoglycemia exceeded two hours. Hypoglycemia was observed most frequently during the first 48 hours. In 35.7%, hypoglycemia was not detected with capillary tests. The agreement between the two techniques was good (r = 0.77, p < 0.001), Hypoglycemia was associated with a lower birth weight (OR: 0.99, p = 0.06). Conclusions: Hypoglycemia is frequent with significant duration in very low birth weight neonates. CGMS could be considered for use in these neonates to improve their glycemic control and prevent the associated morbidity.

Clinical Aspects of Neonatal Hypoglycemia: A Mini Review

Introduction: Neonatal hypoglycemia is common and a preventable cause of brain damage. The goal of management is to prevent or minimize brain injury. The purpose of this mini review is to summarize recent advances and current thinking around clinical aspects of transient neonatal hypoglycemia. Results: The groups of babies at highest risk of hypoglycemia are well defined. However, the optimal frequency and duration of screening for hypoglycemia, as well as the threshold at which treatment would prevent brain injury, remains uncertain. Continuous interstitial glucose monitoring in a research setting provides useful information about glycemic control, including the duration, frequency, and severity of hypoglycemia. However, it remains unknown whether continuous monitoring is associated with clinical benefits or harms. Oral dextrose gel is increasingly being recommended as a first-line treatment for neonatal hypoglycemia. There is some evidence that even transient and clinically undetected episodes of neonatal hypoglycemia are associated with adverse sequelae, suggesting that prophylaxis should also be considered. Mild transient hypoglycemia is not associated with neurodevelopmental impairment at preschool ages, but is associated with low visual motor and executive function, and with neurodevelopmental impairment and poor literacy and mathematics achievement in later childhood. Conclusion: Our current management of neonatal hypoglycemia lacks a reliable evidence base. Randomized trials are required to assess the effects of different prophylactic and treatment strategies, but need to be adequately powered to assess outcomes at least to school age.

Neonatal Hypoglycaemia: A Never-Ending Story?

Neonatal hypoglycaemia is a common metabolic disorder presenting in the first days of life and one potentially preventable cause of brain injury. However, a universal approach to diagnosis and management is still lacking. The rapid decrease in blood glucose (BG) after birth triggers homeostatic mechanisms. Most episodes of hypoglycaemia are asymptomatic, and symptoms, when they occur, are nonspecific. Therefore, neonatologists are presented with the challenge of identifying infants at risk who might benefit from a rapid and effective therapy while sparing others unnecessary sampling and overtreatment. There is much controversy regarding the definition of hypoglycaemia, and one level does not fit all infants since postnatal age and clinical situations trigger different accepted thresholds for therapy. The concentration and duration of BG which cause neurological damage are unclear. Recognizing which newborn infants are at risk of hypoglycaemia and establishing protocols for treatment are essential to avoid possible deleterious effects on neurodevelopment. Early breastfeeding may reduce the risk of hypoglycaemia, but in some cases, the amount of breast milk available immediately after birth is insufficient or non-existent. In these situations, other therapeutic alternatives such as oral dextrose gel may lower the risk for NICU admissions. Current guidelines continue to be based on expert opinion and weak evidence. However, malpractice litigation related to neurodevelopmental disorders is frequent in children who suffered hypoglycaemia in the neonatal period even if they had other important factors contributing to the poor outcome. This review is aimed to help the practicing paediatricians and neonatologists to comprehend neonatal hypoglycaemia from physiology to therapy, hoping it will result in a rational decision-making process in an area not sufficiently supported by evidence.

Accuracy of continuous glucose monitoring in preterm infants: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Continuous glucose monitoring (CGM) could be a valuable instrument for measurement of glucose concentration in preterm neonate. We undertook a systematic review and meta-analysis to compare the diagnostic accuracy of CGM devices to intermittent blood glucose evaluation methods for the detection of hypoglycaemic or hypoglycaemic events in preterm infants.

DATA SOURCES

A structured electronic database search was performed for studies that assessed the accuracy of CGM against any intermittent blood glucose testing methods in detecting episodes of altered glycaemia in preterm infants. No restrictions were used. Three review authors screened records and included studies.

DATA EXTRACTION

Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. From individual patient data (IPD), sensitivity and specificity were determined using predefined thresholds. The mean absolute relative difference (MARD) of the studied CGM devices was assessed and if those satisfied the accuracy requirements (EN ISO 15197). IPD datasets were meta-analysed using a logistic mixed-effects model. A bivariate model was used to estimate the summary receiver operating characteristic curve (ROC) curve and extract the area under the curve (AUC). The overall level of certainty of the evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation.

RESULTS

Among 4481 records, 11 were included. IPD datasets were obtained for five studies. Only two of the studies showed an MARD lower than 10%, with none of the five CGM devices studied satisfying the European Union (EU) ISO 15197 requirements. Pooled sensitivity and specificity of CGM devices for hypoglycaemia were 0.39 and 0.99, whereas for hyperglycaemia were 0.87 and 0.99, respectively. The AUC was 0.70 and 0.86, respectively. The certainty of the evidence was considered as low to moderate. Limitations primarily related to the lack of representative population, reference standard and CGM device.

CONCLUSIONS

CGM devices demonstrated low sensitivity for detecting hypoglycaemia in preterm infants, however, provided high accuracy for detection of hyperglycaemia.

PROSPERO REGISTRATION NUMBER

CRD42020152248.

Risk factors for postoperative hyperglycemia in neonates

OBJECTIVE

Postoperative hyperglycemia has been shown to be associated with higher morbidity and mortality in pediatric patients. Data on risk factors for neonatal patients is limited. The objective of this study was to identify pre- and intraoperative risk factors associated with postoperative glucose in neonates.

METHODS

We conducted a retrospective cohort study of neonates after surgical procedures between January and December 2016 in a quaternary neonatal intensive care unit. The primary outcome was hyperglycemia defined as serum glucose ≥8.3 mmol/L during the first 4 hours postoperatively. Secondary outcomes included death and length of stay. We assessed the association of risk factors with the postoperative glucose.

RESULTS

In total, 206 surgical procedures (171 patients) were evaluated, among which 178 had serum glucose values during the first 4 hours postoperatively available. The incidence of hyperglycemia was 54% (n = 96). The median (IQR) glucose during the first 4 hours in NICU was 8.4 (6.52-10.65) mmol/L. Risk factors for postoperative hyperglycemia were intraoperative glucose infusion rate (GIR) and gestational age. There was a non-linear relationship between gestational age and postoperative hyperglycemia. Mortality occurred in 6 (7%) in the no-hyperglycemia group and 3 (3%) in the hyperglycemia group (p = 0.31).

CONCLUSIONS

Among the risk factors, intraoperative GIR was identified as a modifiable factor that can reduce postoperative hyperglycemia. A non-linear relationship of gestational age with postoperative glucose provides new insights that may help advance our understanding of the complex mechanisms of glucose homeostasis in neonates.

Experience with Real-Time Continuous Glucose Monitoring in Newborns with Congenital Hyperinsulinemic Hypoglycemia

BACKGROUND

Effective treatment and close monitoring of hypoglycemia in children with congenital hyperinsulinemic hypoglycemia (CHH) is vital to prevent brain damage. The current use of capillary sampling schedules does not provide a comprehensive assessment of glycemic status and fails to detect asymptomatic hypoglycemia episodes.

AIM

To investigate the efficacy and accuracy of a real-time continuous glucose monitoring system (RT-CGMS) in neonates with CHH.

METHODS

A sensor connected to RT-CGMS was inserted into the newborn patients and maintained for at least 6 days during their stay in the hospital. We compared the readings of CGMS with capillary blood glucose values using Bland-Altman analysis.

RESULTS

A total of 110 blood glucose values were compared to readings from the CGMS. All results were calculated and plotted for CGMS values at 0-4, 5-9, 10-14, 15-19, 20-24, and 25-29 min after capillary blood glucose sampling. CGMS readings were highly correlated with blood glucose values, especially during normoglycemia. In case of hypoglycemia, the mean difference between the CGMS and capillary glucose values was higher. Although the false positive rate for hypoglycemia was relatively high in CGMS, RT-CGMS may show some episodes of hypoglycemia earlier than blood measurement.

CONCLUSION

RT-CGMS is accurate during normoglycemia, and it can reduce the number of capillary blood samples in children with CHH.

Continuous glucose monitoring for hypoglycaemia in children: Perspectives in 2020

Hypoglycaemia in children is a major risk factor for adverse neurodevelopment with rates as high as 50% in hyperinsulinaemic hypoglycaemia (HH). A key part of management relies upon timely identification and treatment of hypoglycaemia. The current standard of care for glucose monitoring is by infrequent fingerprick plasma glucose testing but this carries a high risk of missed hypoglycaemia identification. High-frequency Continuous Glucose Monitoring (CGM) offers an attractive alternative for glucose trend monitoring and glycaemic phenotyping but its utility remains largely unestablished in disorders of hypoglycaemia. Attempts to determine accuracy through correlation with plasma glucose measurements using conventional methods such as Mean Absolute Relative Difference (MARD) overestimate accuracy at hypoglycaemia. The inaccuracy of CGM in true hypoglycaemia is amplified by calibration algorithms that prioritize hyperglycaemia over hypoglycaemia with minimal objective evidence of efficacy in HH. Conversely, alternative algorithm design has significant potential for predicting hypoglycaemia to prevent neuroglycopaenia and consequent brain dysfunction in childhood disorders. Delays in the detection of hypoglycaemia, alarm fatigue, device calibration and current high cost are all barriers to the wider adoption of CGM in disorders of hypoglycaemia. However, machine learning, artificial intelligence and other computer-generated algorithms now offer significant potential for further improvement in CGM device technology and widespread application in childhood hypoglycaemia.

Monitoring the incidence, duration and distribution of hyperglycaemia in very-low-birth-weight newborns and identifying associated factors

Objectives Hyperglycaemia is a common metabolic disorder in very-low-birth-weight (VLBW) infants and is associated with increased morbidity and mortality. The objective is to describe the incidence, duration, episodes and distribution of hyperglycaemia during the first 7 days of life of VLBW infants. Methods This is a prospective cohort study of 60 newborns weighing <1,500 g. Blood glucose levels were monitored with a continuous glucose monitoring system (CGMS) during the first 7 days of life. Hyperglycaemia was defined as glucose ≥180 mg/dL (≥10 mmol/L). Results Incidence of hyperglycaemia recorded with the CGMS was 36.6% (95%CI: 24.6-50.1). In almost 74.6±5.48% of these cases the duration of the episode exceeded 30 min and in 45.25% (95%CI: 2.26-57.82) it exceeded 2 h. The condition occurred most frequently during the first 72 h of life. One-fifth of cases were not detected with scheduled capillary tests and 84.6% of these had hyperglycaemic episode durations of 30 min or more. Agreement between the two techniques was very good (r=0.90, p<0.001) and the CGMS proved to be reliable, accurate and safe. Hyperglycaemia detected by a CGMS is associated with lower gestational age (OR: 0.66, p=0.002), lower birth weight (OR: 0.99, p=0.003), the use of ionotropic drugs (OR: 11.07, p=0.005) and death (OR: 10.59, p=0.03), and is more frequent in preterm infants with sepsis (OR: 2.73, p=0.1). No other association was observed. Conclusions A CGMS could be useful during the first week of life in VLBW infants due to the high incidence and significant duration of hyperglycaemia and the high proportion of cases that remain undetected. The advantage of the CGMS is that it is able to detect hyperglycaemic episodes that the capillary test does not.

Management of a case of transient neonatal diabetes mellitus using continuous glucose monitoring

Neonatal diabetes mellitus (NDM) is a very rare disorder and its diagnosis can be challenging especially in mild and transient cases. Herein, we describe a 2.4-kg female infant born at 38 wk of gestation who showed hyperglycemia (388 mg/dL) on Day 1. Intermittent blood sampling showed glucose concentrations of 100–150 mg/dL on Day 2–5. However, continuous glucose monitoring (CGM) from Day 7 revealed hyperglycemia (> 200 mg/dL) after every feeding. The patient required low-dose (0.1–0.2 U/kg/d) insulin therapy for a short period (7 d). During the treatment, hypoglycemic (< 50 mg/dL) events were not detected by real- time CGM. Follow-up CGM from Day 32 showed normoglycemia for 3 full days; therefore, we ascertained that the diabetes had been transient. Later genetic analysis revealed an abnormal methylation pattern on chromosome 6q24, which is the most frequent cause of transient NDM. Most cases of 6q24-related NDM relapse after puberty, implying that long term follow up is required. We speculate that the NDM in this case might not have been diagnosed without CGM. This report highlights the usefulness of CGM for the initial diagnosis, monitoring during insulin therapy, and confirmation of improvement in patients with transient NDM.

Silk/polyols/GOD microneedle based electrochemical biosensor for continuous glucose monitoring

This work illustrates the feasibility of a microneedle based electrochemical biosensor for continuous glucose monitoring. The device consists of three silk/d-sorbitol pyramidal microneedles integrated with platinum (Pt) and silver (Ag) wires and immobilized glucose selective enzyme (glucose oxidase, GOD) during fabrication. The silk/d-sorbitol composite can provide a biocompatible environment for the enzyme molecules. The break strength can be controlled by the ratio of silk to d-sorbitol, which guarantees microneedle penetrate into skin. The enzymatic-amperometric responses and glucose concentration were linearly correlated, and cover physiological conditions. The microneedle displays high stability both in long-term monitoring and storage, even at 37 °C. Our results reveal that this new microneedle biosensor is a promising tool for wearable minimally invasive continuous glucose monitoring in practical applications.

Swedish national guideline for prevention and treatment of neonatal hypoglycaemia in newborn infants with gestational age ≥35 weeks

AIM

Postnatal hypoglycaemia in newborn infants remains an important clinical problem where prolonged periods of hypoglycaemia are associated with poor neurodevelopmental outcome. The aim was to develop an evidence-based national guideline with the purpose to optimise prevention, diagnosis and treatment of hypoglycaemia in newborn infants with a gestational age ≥35 + 0 weeks.

METHODS

A PubMed search-based literature review was used to find actual and applicable evidence for all incorporated recommendations. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach was used for grading the evidence of the recommendations.

RESULTS

Recommendations for the prevention of neonatal hypoglycaemia were extended and updated, focusing on promotion of breastfeeding as one prevention strategy. Oral dextrose gel as a novel supplemental therapy was incorporated in the treatment protocol. A new threshold-based screening and treatment protocol presented as a flow chart was developed.

CONCLUSION

An updated and evidence-based national guideline for screening and treatment of neonatal hypoglycaemia will support standardised regimes, which may prevent hypoglycaemia and the risk for hypoglycaemia-related long-term sequelae.

Real time continuous glucose monitoring in neonatal intensive care

Hypoglycaemia and hyperglycaemia are common in infants requiring intensive care and are associated with worse clinical outcomes. However, glucose levels are taken infrequently, and there remains controversy regarding optimal management. In adults and children continuous glucose monitoring (CGM) is now established as an important adjunct to caring for patients at risk from dysglycaemia. This technology is also increasingly providing insights into glucose regulation in the newborn, demonstrating significant periods of clinically silent hypoglycaemia and hyperglycaemia. This baseline data will be important to allow the significance of glucose dysregulation on long-term outcomes to be assessed. Small studies have also shown the potential for CGM to safely support targeting of glucose control in preterm infants, and a large multicentre trial is ongoing. Current technology is not specifically designed for use in NICU, but with rapid technological developments, CGM holds promise for the future care of babies in NICU.

Reliability of real-time continuous glucose monitoring in infants

BACKGROUND

Neonatal hypoglycemia is a common and treatable risk factor for neurological impairment. Real-time continuous glucose monitoring (RT-CGM) can show glucose concentration in real time. Using an RT-CGM alarm, physicians can be alerted and intervene in hypoglycemia. No reports, however, have evaluated the reliability of RT-CGM at low glucose levels in infants. This study therefore investigated the difference between blood glucose (BG) and RT-CGM sensor data at low glucose levels and assessed the optimum method of using a hypoglycemic alarm in infants.

METHODS

We enrolled infants whose glycemic management was difficult. We calculated the mean absolute difference (MAD) and mean absolute relative difference (MARD) between BG and RT-CGM sensor data. We compared the MAD and MARD between the low BG fluctuation and high BG fluctuation groups.

RESULTS

We used RT-CGM for 12 patients (29 times) and investigated 448 pairs of BG and RT-CGM sensor data. The MAD between these pairs was 9.3 ± 8.9 mg/dL, and the MARD was 11.5%. The MAD at low glucose was 7.7 ± 6.0 mg/dL, and the MARD was 16.2%. The MAD and MARD were 6.8 ± 5.4 mg/dL and 7.8% in the low fluctuation group and 10.1 ± 9.5 mg/dL and 12.7% in the high fluctuation group, respectively.

CONCLUSIONS

The difference between BG and RT-CGM sensor data changes with the degree of fluctuation in BG. When physicians set the hypoglycemic alarm, consideration of this difference and a change in the alarm setting according to the degree of fluctuation in BG may be useful.

Targeting glucose control in preterm infants: pilot studies of continuous glucose monitoring

OBJECTIVE

Hyperglycaemia is common in very preterm infants and is associated with adverse outcomes. Preventing hyperglycaemia without increasing the risk of hypoglycaemia is difficult. Real time tracking with continuous glucose monitors (CGM) may improve glucose control. We assessed the feasibility and safety of CGM to target glucose control in preterm infants, to inform a randomised controlled trial (RCT).

DESIGN

We performed a single centre study in very preterm infants during the first week of life. Accuracy was assessed by comparison of CGM with blood glucose levels (n=20 infants). In a separate pilot study of efficacy (n=20), real-time CGM combined with a paper guideline to target glucose control (2.6-10 mmol/L) was compared with standard neonatal care (masked CGM). Questionnaires were used to assess staff acceptability.

RESULTS

No concerns were raised about infection or skin integrity at sensor site. The sensor performed well compared with point-of-care blood glucose measurements, mean bias of -0.27 (95% CI -0.35 to -0.19). Per cent time in target range (sensor glucose 2.6-10 mmol/L) was greater with CGM than POC (77% vs 59%, respectively) and per cent time sensor glucose >10 mmol/L was less with CGM than POC (24% vs 40%, respectively). The CGM also detected clinically unsuspected episodes of hypoglycaemia. Staff reported that the use of the CGM positively improved clinical care.

CONCLUSIONS

This study suggests that CGM has sufficient accuracy and utility in preterm infants to warrant formal testing in a RCT.

Hyperglycemia and Glucose Variability Are Associated with Worse Brain Function and Seizures in Neonatal Encephalopathy: A Prospective Cohort Study

OBJECTIVES

To investigate how glucose abnormalities correlate with brain function on amplitude-integrated electroencephalography (aEEG) in infants with neonatal encephalopathy.

STUDY DESIGN

Neonates born at full term with encephalopathy were enrolled within 6 hours of birth in a prospective cohort study at a pediatric academic referral hospital. Continuous interstitial glucose monitors and aEEG were placed soon after birth and continued for 3 days. Episodes of hypoglycemia (≤50 mg/dL; ≤2.8 mmol/L) and hyperglycemia (>144 mg/dL; >8.0 mmol/L) were identified. aEEG was classified in 6-hour epochs for 3 domains (background, sleep-wake cycling, electrographic seizures). Generalized estimating equations assessed the relationship of hypo- or hyperglycemia with aEEG findings, adjusting for clinical markers of hypoxia-ischemia (Apgar scores, umbilical artery pH, and base deficit).

RESULTS

Forty-five infants (gestational age 39.5 ± 1.4 weeks) were included (24 males). During aEEG monitoring, 16 episodes of hypoglycemia were detected (9 infants, median duration 77.5, maximum 220 minutes) and 18 episodes of hyperglycemia (13 infants, median duration 237.5, maximum 3125 minutes). Epochs of hypoglycemia were not associated with aEEG changes. Compared with epochs of normoglycemia, epochs of hyperglycemia were associated with worse aEEG background scores (B 1.120, 95% CI 0.501-1.738, P < .001), less sleep-wake cycling (B 0.587, 95% CI 0.417-0.757, P < .001) and more electrographic seizures (B 0.433, 95% CI 0.185-0.681, P = .001), after adjusting for hypoxia-ischemia severity.

CONCLUSIONS

In neonates with encephalopathy, epochs of hyperglycemia were temporally associated with worse global brain function and seizures, even after we adjusted for hypoxia-ischemia severity. Whether hyperglycemia causes neuronal injury or is simply a marker of severe brain injury requires further study.

Factors influencing glycaemic stability after neonatal hypoglycaemia and relationship to neurodevelopmental outcome

Higher and unstable glucose concentrations in the first 48 hours in neonates at risk of hypoglycaemia have been associated with neurosensory impairment. It is unclear what defines and contributes to instability. This was a prospective study of term and late preterm babies (N = 139) born at risk of neonatal hypoglycaemia who had interstitial glucose (IG) monitoring and ≥1 hypoglycaemic episode <48 hours after birth (blood glucose concentration <2.6 mmol/l [<47 mg/dl]). For 6-hour epochs after each hypoglycaemic episode, masked IG parameters (time to reach maximum IG concentration [hours]; range, average, maximum and minimum IG concentrations; proportion of IG measurements outside the central band of 3–4 mmol/l [54–72 md/dl]; and total duration [hours] of IG concentrations <2.6 mmol/l) were analysed in tertiles and related to: (i) glycaemic instability in the first 48 hours (defined as the proportion of blood glucose concentrations outside the central band in the first 48 hours); (ii) risk factors and treatment for each episode; and (iii) risk of neurosensory impairment at 4.5 years, or at 2 years if a child was not seen at 4.5 years. Glycaemic instability in the first 48 hours was related to IG instability after hypoglycaemia. Risk factors for hypoglycaemia were not related to IG parameters. Treatment with intravenous dextrose was associated with higher IG maximum and range, and lower minimum compared to treatment with dextrose gel plus breast milk, breast milk alone or formula alone. The risk of neurosensory impairment was increased with both shorter and longer time to reach maximum epoch IG (P = 0.04; lower tertile [0.4–2.2 hours] vs middle [2.3–4.2 hours] OR 3.10 [95% CI 1.03; 9.38]; higher tertile [4.3–6.0 hours] vs middle OR 3.07; [95% CI 1.01; 9.24]). Glycaemic response to hypoglycaemia contributes to overall glycaemic instability in newborns and is influenced by treatment. Slow or rapid recovery of hypoglycaemia appears to be associated with neurosensory impairment.

A Feasibility Study to Detect Neonatal Hypoglycemia in Infants of Diabetic Mothers Using Real-Time Continuous Glucose Monitoring

BACKGROUND

Infants born to mothers with diabetes commonly experience asymptomatic hypoglycemia after birth. Continuous glucose monitors (CGM) can detect asymptomatic hypoglycemia in this population without the need for painful glucose checks.

METHODS

Infants born after 34 weeks of gestation to mothers with diabetes had a CGM placed after birth. One group of infants was remotely monitored in real-time by research staff during the hospitalization, whereas another group wore a blinded CGM. In both groups, hospital standard-of-care (SOC) glucose checks were performed. Clinical staff and families were blinded to CGM data. For CGM readings <45 mg/dL, research staff requested a verification blood glucose (BG) using the point-of-care glucometer.

RESULTS

Sixteen infants were studied; 4 with a blinded CGM and 12 with remote monitoring (RM). When there were confirmatory hospital glucometer readings, the sensitivity of the CGM to detect hypoglycemia was 86% and the specificity was 91%. The positive predictive value was 55% and the negative predictive value was 98%. In the full cohort, hypoglycemia (<45 mg/dL) was confirmed in 12 of 16 infants with 30 events at <12 hours of life (HOL), 3 events between 12 and 24 HOL, and 1 event at >48 HOL. In the RM group, CGM detected hypoglycemia five times when the infant was not due for a BG check based on the SOC. Overall, the CGM detected five false-positive alerts and six true-positive alerts for hypoglycemia. Only one hypoglycemic episode was missed by CGM in the RM group. Barriers to recruitment included fear of pain with glucose checks, concerns with CGM use, satisfaction with the hospital SOC, personal reasons independent of the study, and lack of interest in participating in research.

CONCLUSIONS

Although there were barriers to recruitment and retention in the study, we conclude that CGM can provide added benefit for detecting hypoglycemia when used early after birth.

Continuous Glucose Monitoring Systems: Are They Useful for Evaluating Glycemic Control in Children with Hyperinsulinism?

BACKGROUND

Effective treatment and close monitoring in children with congenital hyperinsulinism (HI) are important to prevent hypoglycemic-associated brain damage. The current monitoring approach involves measuring plasma glucose intermittently, but this does not provide a comprehensive assessment of glycemic control and may fail to detect episodes of hypoglycemia.

OBJECTIVE

To determine whether Dexcom G5®, a continuous glucose monitoring system (CGMS), is an accurate and effective method for monitoring glycemic control in children with HI.

METHODS

Cross-sectional, observational study in 15 children with HI. Participants wore a blinded Dexcom G5® device for 2 weeks. At the end of 2 weeks, data from the Dexcom G5® and home glucose meter were downloaded and analyzed.

RESULTS

Fourteen children (15-67 months) completed the study. Using Bland-Altman analysis, the mean (SD) difference between 1,155 paired CGM and glucose meter readings was -8.09 (53.76). The sensitivity and specificity of CGM to detect hypoglycemia (<70 mg/dL) were 86 and 81.4%, respectively. The positive predictive values for hypoglycemia and severe hypoglycemia (<54 mg/dL) detected by CGM were low (50.3 and 14.8%, respectively), while the negative predictive values were high (96.4% for glucose <70 mg/dL and 99.1% for glucose <54 mg/dL).

CONCLUSION

Our study showed that CGM is not a reliable method to monitor for hypoglycemia, given the high number of false positive hypoglycemia readings. However, CGM can be useful in preventing unnecessary checks by glucose meter during times of normoglycemia. Therefore, the benefits of using CGM in patients with HI would be in guiding the need to check plasma glucose by glucose meter rather than point accuracy.

A Feasibility Study of Paired Continuous Glucose Monitoring Intrapartum and in the Newborn in Pregnancies Complicated by Type 1 Diabetes

AIM

To describe the continuous glucose monitoring (CGM) profiles of type 1 diabetes (T1D) offspring in the early neonatal period and its association with maternal intrapartum glucose control.

METHODS

A prospective observational study of T1D pregnant women and their neonatal offspring. Women had a CGM sensor inserted 2-3 days before delivery. Infants had a masked CGM sensor inserted as soon as possible after delivery. Maternal glycemic outcomes were time-in-target (70-140 mg/dL [3.9-7.8 mmol/L]), hyperglycemia >140 mg/dL (7.8 mmol/L), and mean CGM glucose during the 24 h preceding delivery. Neonatal outcomes included lowest recorded blood glucose concentration, and CGM measures (glucose <47 mg/dL [2.6 mmol/L], time-in-target (47-144 mg/dL [2.6-8.0 mmol/L]), glucose standard deviation [SD]) during the first 72 h of life.

RESULTS

Data were available for 16 mother-infant pairs. Mothers had a mean age (SD) 32.3 (4.3) years, T1D duration 17.6 (6.8) years, first antenatal glycated hemoglobin 7.4 (0.8)% (57 [8.5] mmol/mol). In the 24 h preceding delivery, mothers spent mean (SD) 72 (20)% time-in-target (70-140 mg/dL [3.9-7.8 mmol/L]), 19 (15)% time >140 mg/dL (7.8 mmol/L), and 9 (9)% time <70 mg/dL (3.9 mmol/L) with mean (SD) CGM glucose 113 (9) mg/dL (6.3 [0.7] mmol/L). Fifteen infants (93.8%) had ≥1 blood glucose concentration <47 mg/dL (2.6 mmol/L), and five had ≥1 blood glucose concentration <18 mg/dL (1.0 mmol/L). The mean infant CGM glucose on days 1, 2, and 3 of life was 63 (14), 67 (13), 76 (11) mg/dL (3.5 [0.8], 3.7 [0.7], and 4.2 [0.6] mmol/L). Four infants (25%) spent >50% time with CGM glucose levels <47 mg/dL (2.6 mmol/L) on day 1.

CONCLUSIONS

CGM detected widespread neonatal hypoglycemia, even among mothers with good intrapartum glucose control.