Neonatal blood glucose concentrations: metabolic effects of intravenous glucagon and intragastric medium chain triglyceride

Oral dextrose gel for the treatment of hypoglycaemia in newborn infants

BACKGROUND

Neonatal hypoglycaemia, a common condition, can be associated with brain injury. It is frequently managed by providing infants with an alternative source of glucose, often given enterally with milk-feeding or intravenously with dextrose solution, which may decrease breastfeeding success. Intravenous dextrose also often requires that mother and baby are cared for in separate environments. Oral dextrose gel is simple and inexpensive, and can be administered directly to the buccal mucosa for rapid correction of hypoglycaemia, in association with continued breastfeeding and maternal care. This is an update of a previous review published in 2016.

OBJECTIVES

To assess the effectiveness of oral dextrose gel in correcting hypoglycaemia in newborn infants from birth to discharge home and reducing long-term neurodevelopmental impairment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase from database inception to October 2021.  We also searched international clinical trials networks, the reference lists of included trials, and relevant systematic reviews identified in the search.  SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing oral dextrose gel versus placebo, no treatment, or other therapies for the treatment of neonatal hypoglycaemia in newborn infants from birth to discharge home.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data; they did not assess publications for which they were study authors. We contacted investigators to obtain additional information. We used fixed-effect models and the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included two studies conducted in high-income countries, involving 312 late preterm and at-risk term infants and comparing oral dextrose gel (40% concentration) to placebo gel. One study was at low risk of bias, and the other (an abstract) was at unclear to high risk of bias. Oral dextrose gel compared with placebo gel probably increases correction of hypoglycaemic events (rate ratio 1.08, 95% confidence interval (CI) 0.98 to 1.20; rate difference 66 more per 1000, 95% CI 17 fewer to 166 more; 1 study; 237 infants; moderate-certainty evidence), and may result in a slight reduction in the risk of major neurological disability at age two years or older, but the evidence is uncertain (risk ratio (RR) 0.46, 95% CI 0.09 to 2.47; risk difference (RD) 24 fewer per 1000, 95% CI 41 fewer to 66 more; 1 study, 185 children; low-certainty evidence). The evidence is very uncertain about the effect of oral dextrose gel compared with placebo gel or no gel on the need for intravenous treatment for hypoglycaemia (RR 0.78, 95% CI 0.46 to 1.32; RD 37 fewer per 1000, 95% CI 91 fewer to 54 more; 2 studies, 312 infants; very low-certainty evidence). Investigators in one study of 237 infants reported no adverse events (e.g. choking or vomiting at the time of administration) in the oral dextrose gel or placebo gel group (low-certainty evidence).  Oral dextrose gel compared with placebo gel probably reduces the incidence of separation from the mother for treatment of hypoglycaemia (RR 0.54, 95% CI 0.31 to 0.93; RD 116 fewer per 1000, 95% CI 174 fewer to 18 fewer; 1 study, 237 infants; moderate-certainty evidence), and increases the likelihood of exclusive breastfeeding after discharge (RR 1.10, 95% CI 1.01 to 1.18; RD 87 more per 1000, 95% CI 9 more to 157 more; 1 study, 237 infants; moderate-certainty evidence).   AUTHORS' CONCLUSIONS: Oral dextrose gel (specifically 40% dextrose concentration) used to treat hypoglycaemia in newborn infants (specifically at-risk late preterm and term infants) probably increases correction of hypoglycaemic events, and may result in a slight reduction in the risk of major neurological disability at age two years or older. Oral dextrose gel treatment probably reduces the incidence of separation from the mother for treatment and increases the likelihood of exclusive breastfeeding after discharge. No adverse events have been reported. Oral dextrose gel is probably an effective and safe first-line treatment for infants with neonatal hypoglycaemia in high-income settings.  More evidence is needed about the effects of oral dextrose gel treatment on later neurological disability and the need for other treatments for hypoglycaemia. Future studies should be conducted in low-and middle-income settings, in extremely and moderately preterm infants, and compare oral dextrose gel with other therapies such as intravenous dextrose. There are two ongoing studies that may alter the conclusions of this review when published.

Glucagon for Neonatal Hypoglycaemia: Systematic Review and Meta-Analysis

INTRODUCTION

Glucagon is often used in neonatal hypoglycaemia, but its effects have not been systematically assessed. We undertook a systematic review to determine the efficacy and safety of glucagon treatment for neonatal hypoglycaemia.

METHODS

We searched MEDLINE, CINAHL, EMBASE, and CENTRAL from inception until May 2021. We included studies that reported one or more prespecified outcomes and compared glucagon with placebo or no glucagon. Studies were excluded if the majority (>70%) of participants were >1 month of age. Two authors independently extracted data. We used ROB-2/modified ROBINS-I to assess risk of bias, GRADE for certainty of evidence, and RevMan for meta-analysis.

RESULTS

100 studies were screened, 37 reviewed in full, and seven single-arm non-randomised intervention studies, involving 348 infants, were included (no trials). Data were insufficient to undertake meta-analysis of the critical outcomes (time to blood glucose normalization, recurrent hypoglycaemia, neurocognitive impairment). In 3 studies, ≥80% of neonates achieved normoglycaemia within 4 h of glucagon administration. However, recurrent hypoglycaemia was common (up to 55%). Glucagon increased blood glucose concentration at 1-2 h by 2.3 mmol/L (95% CI 2.1, 2.5) (low certainty evidence, 6 studies, N = 323). There were few data for other important clinical outcomes.

CONCLUSION

There is a paucity of evidence about the efficacy and safety of glucagon for treatment of neonatal hypoglycaemia. Low certainty evidence suggests that glucagon may increase blood glucose by ∼2.3 mmol/L but recurrent hypoglycaemia appears common. High-quality, randomized controlled trials are required to determine the role of glucagon in managing neonatal hypoglycaemia.

The use of intramuscular glucagon to prevent IV glucose infusion in early neonatal hypoglycemia

OBJECTIVE

To investigate the success rate of intramuscular (IM) glucagon in preventing need for IV glucose and describe its glycemic effect.

METHODS

Retrospective study of 158 consecutive term neonates with feeding-resistant hypoglycemia treated with glucagon.

RESULTS

After glucagon, blood glucose (BG) increased in all but 1 infant by 25.9 ± 17.1, 42.1 ± 21.1, and 39.2 ± 28.3 mg/dL (1.4 ± 0.9, 2.3 ± 1.2, 2.2 ± 1.6 mmol/L) at 30, 60 and 120 mins respectively. In multivariable logistic regression, glucagon success was dependent upon gender (increased male risk) (P = 0.021), meeting American Academy of Pediatrics (AAP) criteria for immediate IV glucose (P = 0.004), birth weight, (P = 0.018) and delta glucose concentration at 60 min (P = 0.013). After IM glucagon, 24 out of 49 infants that met AAP criteria for immediate IV glucose (49%) ended up not requiring any additional intervention.

CONCLUSIONS

Glucagon increases BG nearly universally in hypoglycemic infants and allowed reducing the number of infants that needed immediate IV glucose infusion therapy by ≈half.

A comparison of the glycemic effects of glucagon using two dose ranges in neonates and infants with hypoglycemia

INTRODUCTION

Consensus regarding optimal glucagon dosing for management or diagnosis of neonatal/infant hypoglycemia has not been established.

OBJECTIVE

To investigate glycemic effects of glucagon dosed ≤0.2 mg/kg (Gn_low) vs. >0.2 mg/kg (Gn_high) in neonatal/infant hypoglycemia.

STUDY DESIGN

Retrospective, observational, cohort study.

RESULTS

Glucagon administration at any dose resulted in 75/77 (97.4%) samples meeting criteria for normoglycemia (plasma glucose >60 mg/dL), and plasma glucose increases of >30 mg/dL occurred in 74.2% vs. 63% (NS) of samples in the Gn_low and Gn_high groups, respectively. Despite equivalent glucagon dosing, there was a trend toward smaller (<2500 g) patients achieving post-glucagon plasma glucose increases of >30 mg/dL less often than their bigger (≥2500 g) counterparts (60% vs. 74.1%, NS).

CONCLUSIONS

Glucagon is highly effective in raising plasma glucose levels in neonatal/infant hypoglycemia. No differences in glycemic effects were noted between either dosing regimen. However, glycemic effects may be diminished in lower weight patients.

Glucagon therapy in canines with an insulinoma: A retrospective descriptive study of 11 dogs

Canine insulinomas are uncommon neoplasms, which often result in refractory hypoglycemia. Glucagon is one readily available treatment for insulin-induced hypoglycemia. The primary objective of this study was to evaluate blood glucose trends and outcome (survival to discharge versus death or euthanasia) for dogs with insulinoma that were treated with glucagon. Secondary objectives included the description and influence of other variables such as abnormalities on diagnostic tests, physical examination abnormalities, concurrent administration of dextrose and/or glucocorticoids, and seizures. The median glucagon constant rate infusion dose was significantly higher for the non-survivors than for survivors. No other correlation was found between any of the independent variables evaluated when comparing blood glucose trends, length of hospitalization, and outcome. The main conclusion of the study is that glucagon therapy in insulinomas is an effective treatment to manage hypoglycemia.

The screening and management of newborns at risk for low blood glucose

Hypoglycemia in the first hours to days after birth remains one of the most common conditions facing practitioners across Canada who care for newborns. Many cases represent normal physiologic transition to extrauterine life, but another group experiences hypoglycemia of longer duration. This statement addresses key issues for providers of neonatal care, including the definition of hypoglycemia, risk factors, screening protocols, blood glucose levels requiring intervention, and managing care for this condition. Screening, monitoring, and intervention protocols have been revised to better identify, manage, and treat infants who are at risk for persistent, recurrent, or severe hypoglycemia. The role of dextrose gels in raising glucose levels or preventing more persistent hypoglycemia, and precautions to reduce risk for recurrence after leaving hospital, are also addressed. This statement differentiates between approaches to care for hypoglycemia during the 'transitional' phase-the first 72 hours post-birth-and persistent hypoglycemia, which occurs or presents for the first time past that point.

Le dépistage et la prise en charge des nouveau-nés à risque d’hypoglycémie

L’hypoglycémie entre les premières heures et les premiers jours suivant la naissance demeure l’une des principales affections qu’observent les praticiens du Canada qui s’occupent de nouveau-nés. Bien des cas vivent une transition physiologique normale à la vie extra-utérine, mais un groupe présente une hypoglycémie pendant une plus longue période. Le présent document de principes expose les principaux enjeux auxquels sont exposés les dispensateurs de soins néonatals, y compris la définition d’hypoglycémie, les facteurs de risque, les protocoles de dépistage, les valeurs de glycémie nécessitant une intervention et la gestion des soins pour cette affection. Les auteurs passent en revue le dépistage, la surveillance et les protocoles d’intervention pour mieux distinguer, prendre en charge et traiter les nouveau-nés à risque d’hypoglycémie persistante, récurrente ou marquée. Ils abordent également le rôle des gels de dextrose pour accroître la glycémie ou prévenir une hypoglycémie plus persistante, de même que les précautions à prendre pour réduire les risques de récurrence après le congé de l’hôpital. Le présent document de principes distingue les approches des soins de l’hypoglycémie pendant la « phase de transition » (les 72 premières heures de vie) de celles de l’hypoglycémie persistante, qui se manifeste ou est constatée pour la première fois après cette période.

Oral dextrose gel for the treatment of hypoglycaemia in newborn infants

BACKGROUND

Neonatal hypoglycaemia, a common condition, can be associated with brain injury. It is frequently managed by providing infants with an alternative source of glucose, given enterally with formula or intravenously with dextrose solution. This often requires that mother and baby are cared for in separate environments and may inhibit breast feeding. Dextrose gel is simple and inexpensive and can be administered directly to the buccal mucosa for rapid correction of hypoglycaemia, in association with continued breast feeding and maternal care.

OBJECTIVES

To assess the effectiveness of dextrose gel in correcting hypoglycaemia and in reducing long-term neurodevelopmental impairment.

SEARCH METHODS

We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Web of Science from inception of the database to February 2016. We also searched international clinical trials networks and handsearched proceedings of specific scientific meetings.

SELECTION CRITERIA

Randomised and quasi-randomised studies comparing dextrose gel versus placebo, no treatment or other therapies for treatment of neonatal hypoglycaemia.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data and did not assess publications for which they themselves were study authors.

MAIN RESULTS

We included two trials involving 312 infants. No data were available for correction of hypoglycaemia for each hypoglycaemic event. We found no evidence of a difference between dextrose gel and placebo gel for major neurosensory disability at two-year follow-up (risk ratio (RR) 6.27, 95% confidence interval (CI) 0.77 to 51.03; one trial, n = 184; quality of evidence very low). Dextrose gel compared with placebo gel or no gel did not alter the need for intravenous treatment for hypoglycaemia (typical RR 0.78, 95% CI 0.46 to 1.32; two trials, 312 infants; quality of evidence very low). Infants treated with dextrose gel were less likely to be separated from their mothers for treatment of hypoglycaemia (RR 0.54, 95% CI 0.31 to 0.93; one trial, 237 infants; quality of evidence moderate) and were more likely to be exclusively breast fed after discharge (RR 1.10, 95% CI 1.01 to 1.18; one trial, 237 infants; quality of evidence moderate). Estimated rise in blood glucose concentration following dextrose gel was 0.4 mmol/L (95% CI -0.14 to 0.94; one trial, 75 infants). Investigators in one trial reported no adverse outcomes (n = 237 infants).

AUTHORS' CONCLUSIONS

Treatment of infants with neonatal hypoglycaemia with 40% dextrose gel reduces the incidence of mother-infant separation for treatment and increases the likelihood of full breast feeding after discharge compared with placebo gel. No evidence suggests occurrence of adverse effects during the neonatal period or at two years' corrected age. Oral dextrose gel should be considered first-line treatment for infants with neonatal hypoglycaemia.

Glucose metabolism in children: influence of age, fasting, and infectious diseases

This review describes the occurrence of hypoglycemia in young children as a common and serious complication that needs to be avoided because of the high risk of brain damage and mortality. Young age, fasting, and severe infectious disease are considered important risk factors. The limited data on the effect of these risk factors on glucose metabolism in children are discussed and compared with data on glucose metabolism in adults. The observations discussed may have implications for further research on glucose kinetics in young children with infectious disease.

Lipolysis and insulin sensitivity at birth in infants who are large for gestational age

OBJECTIVE

In addition to neonatal hypoglycemia, infants who are born large for gestational age are at risk for developing obesity, cardiovascular disease, and diabetes later in life. The aim of this study was to investigate glucose production, lipolysis, and insulin sensitivity in infants who were born large for gestational age to mothers without diabetes. The effect of glucagon administration on production of energy substrates was also investigated.

METHODS

Ten healthy term infants who were born large for gestational age to mothers without diabetes were studied 16 +/- 8 hours postnatally after a 3-hour fast. Rates of glucose production and lipolysis were analyzed by gas chromatography-mass spectrometry following constant rate infusion of [6,6-(2)H2]glucose and [2-(13)C]glycerol. Insulin sensitivity was assessed by the Homeostasis Assessment Model. In 8 of the infants, the effect of an intravenous injection of 0.2 mg/kg glucagon was also analyzed.

RESULTS

Plasma glucose and glycerol averaged 3.8 +/- 0.5 mmol/L and 384 +/- 183 micromol/L, respectively. The glycerol production rate, reflecting lipolysis, was 12.7 +/- 2.9 micromol/kg per min. Mean rate of glucose production was 30.2 +/- 4.6 micromol/kg per min. Homeostasis Assessment Model insulin sensitivity corresponded to 82% +/- 19%, beta-cell function to 221% +/- 73%, and insulin resistance to 1.3 +/- 0.3. After glucagon administration, rate of glucose production increased by 13.3 +/- 8.3 micromol/kg per min and blood glucose by 1.4 +/- 0.5 mmol/L. Glycerol production decreased from 12.8 +/- 3.0 to 10.7 +/- 2.9 micromol/kg per min. Mean insulin concentration increased from 10.9 +/- 3.0 to 30.9 +/- 10.3 mU/L. There was a strong inverse correlation between the decrease in lipolysis and increase in insulin after glucagon administration.

CONCLUSIONS

Infants who are born large for gestational age show increased lipolysis and a propensity for decreased insulin sensitivity already at birth. The simultaneous increase in plasma insulin correlated strongly with the noted decrease in lipolysis, indicating an antilipolytic effect of insulin in these infants.

Stimulation of gluconeogenesis by intravenous lipids in preterm infants: response depends on fatty acid profile

In preterm infants, both hypo- and hyperglycemia are a frequent problem. Intravenous lipids can affect glucose metabolism by stimulation of gluconeogenesis by providing glycerol, which is a gluconeogenic precursor, and/or free fatty acids (FFA), which are stimulants of the rate of gluconeogenesis. In 25 preterm infants, glucose production and gluconeogenesis were measured using stable isotope techniques during a 6-h infusion of glucose only, glucose plus glycerol, or glucose plus an intravenous lipid emulsion. Two lipid emulsions differing in FFA composition were used: Intralipid ( approximately 60% polyunsaturated FFA) and Clinoleic (approximately 60% monounsaturated FFA). The rate of glucose infusion was 22 micromol x kg(-1) x min(-1) in all groups. During the study infusion, the FFA concentrations were higher in both lipid groups vs. the glycerol group (P < 0.001). Compared with baseline, the glucose production rate increased in the Intralipid group, whereas it decreased in the other groups (P = 0.002) due to a significant increase in gluconeogenesis in the Intralipid group (P = 0.016). The plasma glucose concentration was significantly higher during Intralipid infusion vs. the other groups (P = 0.046). Our conclusion was that Intralipid enhanced glucose production by increasing gluconeogenesis in preterm infants. This can be ascribed to the stimulatory effect of FFA in addition to any effect of glycerol alone. The lack of stimulation of gluconeogenesis in the Clinoleic vs. the Intralipid group suggests that different classes of fatty acids exert different effects on glucose kinetics in preterm infants.

Glucose production in response to glucagon is comparable in preterm AGA and SGA infants

BACKGROUND AND AIMS

Low plasma glucose concentrations are more often detected in small-for-gestational-age (SGA) than in appropriate-for-gestational-age (AGA) infants. This is ascribed to impaired glucose production due to presumed lower liver glycogen stores in SGA infants. The change in glucose production induced by glucagon is considered to be an indicator of liver glycogen content. We compared the effect of glucagon on glucose kinetics in preterm AGA and SGA infants.

METHODS

In 5 AGA and 5 SGA preterm infants (postnatal age: 3-6 days) glucose production and gluconeogenesis were measured using stable isotopes immediately before and for 1 h after a bolus of glucagon.

RESULTS

After glucagon the plasma glucose concentration and glucose production increased significantly over time (P<0.05 and P<0.0001, respectively). The changes were comparable between AGA and SGA infants. Glycogenolysis contributed 75-80% to the increase in glucose production.

CONCLUSION

The increase in glucose production after glucagon was similar in preterm AGA and SGA infants, and mainly due to an increase in glycogenolysis. Based on the assumption that glycogenolysis is an indicator of liver glycogen content, our data do not support the hypothesis that liver glycogen content is lower in preterm SGA compared to AGA infants after the first postnatal day.

The investigation and management of neonatal hypoglycaemia

Assessment of neonatal glycaemic status requires accurate and reliable measurement of blood glucose concentrations. Most point-of-care technologies are, however, unsuitable for use in neonates. Although the definition of hypoglycaemia remains elusive, current knowledge allows adoption of pragmatic threshold blood glucose concentrations when clinical intervention should be considered. The vast majority of instances of neonatal hypoglycaemia are due to problems with the normal processes of metabolic adaptation after birth, and strategies to enhance the normal adaptive processes should help prevent such episodes. Further investigations and specific interventions should be considered when hypoglycaemia is of unusual severity or occurs in an otherwise low-risk infant.

An inadequate glycaemic response to glucagon is linked to insulin resistance in preterm infants?

AIMS

To define clinical, metabolic, and hormonal characteristics of preterm infants relative to glucagon responsiveness.

METHODS

Two phase study of 78 preterm infants (25-36 weeks gestation) on regular four hourly feeds anticipating discharge home at 36 weeks mean corrected gestation. In phase 1 infants were fasted until hypoglycaemic, or maximally for eight hours. Endocrine and metabolic profiles were obtained at completion. Phase 2 was performed the following day. A feed was omitted and replaced by a bolus dose of intravenous glucagon (100 micro g/kg). Main outcome measures were measurements of blood glucose and lactate concentrations, taken immediately pre-glucagon, and thereafter every 15 minutes for 60 minutes. A rise in glucose concentration of >1 mmol/l (55 infants) was defined as an adequate response to glucagon. An inadequate glycaemic response was <1 mmol/l (23 infants).

RESULTS

Several differences in fasting blood glucose and hormone concentrations were identified in infants with an inadequate glycaemic response to glucagon compared to those with an adequate response: relative fasting hyperglycaemia (mean 3.7 v 3.3 mmol/l, p = 0.008); fasting hyperinsulinaemia (mean 4.3 v 2.6 mU/l, p = 0.014); an increased insulin:glucagon ratio (0.19 v 0.11, p = 0.014), and a lower insulin sensitivity QUICKI index (0.19 v 0.22, p = 0.04). There was no distinctive phenotype to reliably predict response to glucagon.

CONCLUSION

Some preterm infants show an inadequate glycaemic response to glucagon and have features suggestive of insulin resistance. The potential long term implications of such insulin resistance may have appreciable public health consequences.

Continuous infusion of glucagon induces severe hyponatremia and thrombocytopenia in a premature neonate

We report on a 35-week gestation infant who developed severe hyponatremia and thrombocytopenia after continuous infusion of glucagon for the treatment of intractable hypoglycemia. Given these serious side effects,glucagon infusion should be avoided in the treatment of premature infants.hypoglycemia, glucose, small for gestational age. Hypoglycemia is commonly seen in premature infants, and the provision of a standard glucose intake is often not sufficient to maintain euglycemia. For these infants, an increase in glucose infusion to provide 4 to 8 mg/kg/min is initially recommended.1 Should this approach fail, pharmacologic agents such as corticosteroids or diazoxide are indicated.1 When the serum glucose in premature or small for gestational age infants cannot be adequately maintained, a glucagon infusion is now suggested as the best treatment approach.2,3 We report the use of glucagon infusion for the treatment of severe hypoglycemia in a premature infant. A severe hyponatremia associated with transient convulsions and thrombocytopenia was observed in the neonate after treatment. Discontinuation of the glucagon infusion resulted in prompt resolution of these abnormalities.

Hypoglycaemia of the newborn: a review

It is almost a century since hypoglycaemia (a reduction in the glucose concentration of circulating blood) was first described in children, and over 50 years since the condition was first recognized in infants. Nevertheless, controversy still surrounds the definition, significance, and management of neonatal hypoglycaemia. Technological developments such as bedside glucose monitoring have, paradoxically, exacerbated rather than eased the situation. This article reviews the literature on hypoglycaemia of the newborn, and covers the following: historical aspects; glucose homeostasis and metabolic adaptation at birth; the effect of low blood glucose levels on the central nervous system; the definition of hypoglycaemia; screening; prevention; treatment; research needs; and concludes with recommendations for prevention and management.

The role of pancreatic insulin secretion in neonatal glucoregulation. II. Infants with disordered blood glucose homoeostasis

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.