Prevention and management of neonatal hypoglycaemia

Defective Cortisol Secretion in Response to Spontaneous Hypoglycemia but Normal Cortisol Response to ACTH stimulation in neonates with Hyperinsulinemic Hypoglycemia (HH)

Introduction:

Hyperinsulinemic Hypoglycaemia (HH) is the most common cause of recurrent and persistent hypoglycemia in the neonatal period. Cortisol and GH play an important role as a counterregulatory hormone during hypoglycemia. Both antagonize the peripheral effects of insulin and directly influence glucose metabolism

Patients and Methods:

We studied cortisol and GH secretion in newborn infants with HH during spontaneous hypoglycemia. In addition, their basal ACTH level was measured and cortisol response to a standard dose ACTH test was performed.

Results:

Nine newborns with HH were studied during the first 2 weeks of life. During HH, their mean glucose concentration was 1.42 ± 0.7 mmol/L, mean beta hydroxybutyrate level was 0.08 ± 0.04 mmol/L, and mean serum insulin level was 17.78 ± 9.7 μU/mL. Their cortisol and GH levels at the time of spontaneous hypoglycemia were 94.7 ± 83.1 nmol/L and 82.4 ± 29 m IU/L respectively. They had relatively low level of ACTH (range: 14 :72 pg/ml, mean: 39.4 ± 20 pg/mL) during hypoglycemia. All infants had GH concentration > 20 mIU/L at the time of hypoglycemia. All infants underwent ACTH test. Their basal serum cortisol levels did not differ compared to cortisol levels during hypoglycemia, and all had a normal peak cortisol response (> 500 nmol/L) in response to i.v. ACTH stimulation test.

Conclusion:

Infants with HH have low cortisol response to spontaneous hypoglycemia with normal response to exogenous standard-dose ACTH. Checking hypothalamic-pituitary axis (HPA) axis later in infancy using low dose ACTH may be useful to diagnose persistent HPA abnormalities in these infants. All HH infants had appropriate elevation of GH during hypoglycemia. (www.actabiomedica.it)

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.

Neonatal Hypoglycemia: Risk Factors and Outcomes

BACKGROUND AND AIMS

Severe neonatal hypoglycemia (HG) leads to neurologic damage, mental retardation, epilepsy, personality disorders, impaired cardiac performance and muscle weakness. We aimed to assess the clinical characteristics of children with hypoglycemia in a random population of newborns.

PATIENTS, METHODS AND RESULTS

We investigated 84 patients (M:F=35:48) born at the University Clinic for Gynecology and Obstetrics in Skopje (hospitalized in the NICU) who were found to have hypoglycemia. In total 89.25% of the babies were premature. The mean birth weight was 1795.95 +/596.08 grams, the mean birth length was 41.92+/- 4.62 cm, while the mean gestational age was 33.05±3.19 weeks. 32 children (38.08%) were very low birth weight (<1500g), 38 (45.22%) were low birth weight (1500-2500g), while there were 8 children (9.52%) appropriate for age BW and no high BW for age patients (>4000 g). HG duration was 2.42+/-2.41 hours. In the group as a whole, hypoxic-ischemic encephalopathy (HIE) was found in 3 children (3.57%), infections in 22 (26.18%), respiratory distress syndrome (RDS) in 9 patients (10.62%), intracranial haemorrhage in 2 patients (2.38%). There were no inborn errors of metabolism. There were two deaths (2.38%).

CONCLUSION

Neonatal HG is a significant factor in the overall neonatal mortality. HG can also cause severe invalidity. We found that infections, LBW and low gestational age were most commonly associated with neonatal HG. However the Spearman test showed weak direct correlation, without statistical significance. Neonatal HG requires complex and team interaction of prenatal and postnatal approaches to reduce the incidence of seizures, their consequences and the overall mortality. Special consideration is to be taken in measures that avoid neonatal infections, HIE, LBW and low gestational age. Further studies on a larger population are needed to fully understand and prevent the phenomenon of HG in newborns.

Continued Enteral Feeding Is Beneficial in Hypoglycemic Infants Admitted to Intensive Care for Parenteral Dextrose Therapy

There is variability in practice among care providers on feeding infants admitted with neonatal hypoglycemia (NH) for parenteral dextrose. We compared clinical outcomes in infants who were fed (NH-Fed) and hypoglycemic infants who were kept nothing per os (NPO) (NH-NPO) at the time of initiation of intravenous (IV) dextrose. We performed a retrospective review of all newborn infants admitted to the neonatal intensive care unit with NH for IV dextrose. Infants were grouped as per the feeding approach at initiation of IV dextrose: NH-Fed or NH-NPO infants. We found that infants in the NH-Fed group had lower maximum glucose infusion rate, less duration of glucose infusion therapy compared with the NH-NPO group, and significantly less number of days of hospital stay compared with the NH-NPO group (5.87 ± 1.4 days vs 4.9 ± 1.4 days, P < .006). In conclusion, feeding infants with hypoglycemia who require IV dextrose offers tangible benefits of shorter duration of parenteral dextrose and shorter length of hospitalization.

Neonatal Hypoglycemia: Is There a Sweet Spot?

Hypoglycemia is one of the most common neonatal problems. Despite increasing evidence that hypoglycemia is linked to neurologic impairment, knowledge regarding the specific value or duration of hypoglycemia that results in injury to the brain remains unclear. Current published statements/guidelines focused on preventing clinically significant hypoglycemia are conflicting and continue to be based on low evidence. This article reviews transitional events leading to extrauterine euglycemia, risk factors contributing to transient or persistent hypoglycemia, and common treatment approaches. Current information related to neurodevelopmental outcomes and screening strategies to prevent significant hypoglycemia with early treatment is described.

Hypoglycaemia in the Newborn

AIM

Severe neonatal hypoglycaemia (HG) leads to neurologic damage, mental retardation, epilepsy, impaired cardiac performance and muscle weakness. The aim was to assess the frequency and severity of HG in a population of newborns.

PATIENTS AND METHODS

We investigated 739 patients with neonatal hypoglycaemia (HG) (M:F=370:369) born at the University Clinic for Gynaecology and Obstetritics in Skopje in the period 2014-2016 and treated at the neonatal intensive care unit (NICU). 1416 babies were treated in the same period in NICU, and HG was observed in 52.18%. The birth weight was dominated by children with low birth weight: very low birth weight (VLBW)(<1500g) 253 children, (34,23%), low birth weight (1500-2500g) 402 (54.39%), appropriate for gestational age (AGA) 78(10.55%), and high birth weight (>4000g) 6 babies (0.81%). The gestational age was also dominated by children with low gestational age: gestational week (GW) 20-25 four children (0.54%), 26-30 GW 133 babies (17.99%), 31-35 GW472 (63.87%), and 36-40 GW130 neonates (17.59 %). 241 mothers (32.61%) have had an infection during pregnancy, 82 preeclampsia or eclampsia (11.09%), 20 diabetes mellitus (2.70%), 78 placental situations (placenta previa, abruption) (10.55%). In this study 47 babies (6.35%) with HG and co-morbidities died. There was a significant positive correlation between HG birth weight (p<0.01), gestational age (p<0.05), and the lowest Apgar score (p<0.01). Neonatal deaths were significantly correlated with GA (р>0,01), co-morbidities of the mothers (р>0,05) but not with the birth weight (р>0,05). In contrast, a significant positive correlation was found between convulsions and body weight (р<0.05). The lowest Apgar score was positively correlated with the gestational age (0.01), but not with the birth weight (0.05).

CONCLUSION

Low birth weight, low gestational age, maternal risk factors, hypoxic-ischemic encephalopathy and neonatal infections are associated with HG and are a significant factor in overall neonatal mortality. Those results indicate that diminishing the frequency of the neonatal HG and the rates of neonatal mortality requires complex interaction of prenatal and postnatal interventions.

Management strategies for neonatal hypoglycemia

While hypoglycemia occurs commonly among neonates, treatment can be challenging if hypoglycemia persists beyond the first few days of life. This review discusses the available treatment options for both transient and persistent neonatal hypoglycemia. These treatment options include dextrose infusions, glucagon, glucocorticoids, diazoxide, octreotide, and nifedipine. A stepwise, practical approach to the management of these patients is offered.

Glucose monitoring in neonates: need for accurate and non-invasive methods

Neonatal hypoglycaemia can lead to devastating consequences. Thus, constant, accurate and safe glucose monitoring is imperative in neonatal care. However, point-of-care (POC) devices for glucose testing currently used for neonates were originally designed for adults and do not address issues specific to neonates. This review will address currently available monitoring options and describe new methodologies for non-invasive glucose monitoring in newborns.

Early transient hypoglycemia is associated with increased albumin nitration in the preterm infant

BACKGROUND

The clinical significance of early transient hypoglycemia (ETH), a frequent event in preterm newborns, is a highly controversial issue. In experimental models, hypoglycemia has been reported to cause oxidative stress. Among the reactive species, early generated peroxynitrite is responsible for protein nitration and lipid peroxidation, a process referred to as nitrative stress.

OBJECTIVES

The aim of the present study is to investigate whether ETH is associated with protein nitration in the preterm newborn.

METHODS

Using a novel highly sensitive ELISA, we quantified plasma nitroalbumin (PNA) as a marker of peroxynitrite generation in 72 preterm newborns (28-36 weeks), among which 25 had a glycemia level of <2.5 mmol/l during the first hour of life (H1).

RESULTS

PNA was significantly higher in ETH than in normoglycemic infants at H1 [median = 6.3 (3.8-8.8) vs. 3.4 ng/ml (2.1-5.1), p = 0.027] and at day 1 [median = 6.6 (5.6-15.3) vs. 3.9 ng/ml (2.3-4.6), p = 0.014]. PNA was inversely correlated with glycemia at H1 (r = -0.30, p = 0.01) and at day 1 (r = -0.63, p = 0.001). In ETH infants, lactatemia was inversely correlated with PNA. At day 1, PNA was higher in ETH infants treated by gavage than in those treated with intravenous dextrose [median = 8.9 ng/ml (7.1-10.4) vs. 4.4 ng/ml (2.6-5.7), p = 0.008].

CONCLUSIONS

These results indicate that ETH is associated with increased peroxynitrite generation resulting in systemic protein nitration in premature newborns. Treatment of ETH with intravenous dextrose is associated with lower PNA levels than gavage.

Clinical parameters predicting failure of empirical antibacterial therapy in early onset neonatal sepsis, identified by classification and regression tree analysis

BACKGROUND

About 10-20% of neonates with suspected or proven early onset sepsis (EOS) fail on the empiric antibiotic regimen of ampicillin or penicillin and gentamicin. We aimed to identify clinical and laboratory markers associated with empiric antibiotic treatment failure in neonates with suspected EOS.

METHODS

Maternal and early neonatal characteristics predicting failure of empiric antibiotic treatment were identified by univariate logistic regression analysis from a prospective database of 283 neonates admitted to neonatal intensive care unit within 72 hours of life and requiring antibiotic therapy with penicillin or ampicillin and gentamicin. Variables, identified as significant by univariate analysis, were entered into stepwise multiple logistic regression (MLR) analysis and classification and regression tree (CRT) analysis to develop a decision algorithm for clinical application. In order to ensure the earliest possible timing separate analysis for 24 and 72 hours of age was performed.

RESULTS

At 24 hours of age neonates with hypoglycaemia < or = 2.55 mmol/L together with CRP values > 1.35 mg/L or those with BW < or = 678 g had more than 30% likelihood of treatment failure. In normoglycaemic neonates with higher BW the best predictors of treatment failure at 24 hours were GA < or = 27 weeks and among those, with higher GA, WBC < or = 8.25 x 10(9) L(-1) together with platelet count < or = 143 x 10(9) L(-1). The algorithm allowed capture of 75% of treatment failure cases with a specificity of 89%. By 72 hours of age minimum platelet count < or = 94.5 x 10(9) L(-1) with need for vasoactive treatment or leukopaenia < or = 3.5 x 10(9) L(-1) or leukocytosis > 39.8 x 10(9) L(-1) or blood glucose < or = 1.65 mmol/L allowed capture of 81% of treatment failure cases with the specificity of 88%. The performance of MLR and CRT models was similar, except for higher specificity of the CRT at 72 h, compared to MLR analysis.

CONCLUSION

There is an identifiable group of neonates with high risk of EOS, likely to fail on conventional antibiotic therapy.

Evaluation of the Glucometer Elite XL device for screening for neonatal hypoglycaemia

To prevent persistent neurodevelopment and physical growth deficits in neonatal care, it is mandatory to determine blood glucose levels as quickly and precisely as possible, preferably using micro-methods. However, most commercially available instruments have not been validated and approved for this purpose. The aim of this study was to validate the Glucometer Elite XL, a newly developed device for point-of-care testing (POCT). In samples from 869 newborn infants, glucose levels were simultaneously measured by the Glucometer Elite XL in whole blood and by an accepted clinical laboratory method in haemolysed blood using the ECA 2000 device. An acceptable method agreement was found between the POCT and the ECA 2000 method (mean difference 0.013 mmol/l, SD 0.69). As determined by regression analysis (Passing-Bablok), the slope was 1.086 with a y-intercept of -0.4 mmol/l ( r =0.959, P <0.05). The differences between measurement pairs of both assays versus the haematocrit were negligible. With a cut-off for hypoglycaemia at 2.6 mmol/l glucose in haemolysed blood, the sensitivity of the POCT device was 0.63 and specificity was 0.98. Raising the cut-off of the Glucometer Elite XL to 3.2 mmol/l, the sensitivity and specificity incremented to 1.0 and 0.89, respectively.

CONCLUSION

The Glucometer Elite XL instrument can be recommended for point-of-care blood glucose measurement in newborn infants if its character as a screening method is taken into account. To compensate deviating results, we advise to shift its cut-off for hypoglycaemia recognition to a safe threshold of 3.2 mmol/l. However, hypoglycaemia has to be confirmed by a valid glucose measurement in the clinical laboratory.

Glucose homeostasis in the micropremie

This article evaluates the current knowledge of the kinetics of glucose homeostasis in the micropremie. Glucose production, glucose use, and glucose oxidation are reviewed in detail. This article also evaluates the developmental regulation of glucose homeostasis relative to some of the fundamental differences known to exist in the neonate compared to the adult.

The effect of early feeding on the neonatal blood glucose level at 1-hour of age

Early infant feeding after birth is being promoted, although it is unclear whether this has any effect on carbohydrate metabolism. We planned to measure the capillary glucose at one hour (1 h) of age in a group of infants from non-diabetic pregnancies using the HemoCue B-Glucose system to see if the timing and method of early feeding would influence this result. Seventy-five term infants were studied, 22 of which were breast-fed, 24 bottle fed and 29 not fed during the first hour after birth. The mean whole blood glucose results were 2.34 mmol/l, 2.52 mmol/l and 2.58 mmol/l respectively (P = NS). The first two groups were fed at a median of 22 minutes before sampling. We conclude that the timing and method of early feeding in the newborn have no significant effect on the blood glucose level measured at 1 h of age, and this remains a reliable outcome measure in studies of glucose metabolism in pregnancy.

Neonatal hypoglycemia, Part I: Background and definition

Hypoglycemia in the neonate remains a common problem. The association of low blood glucose concentrations and abnormal development has prompted extensive research into the anticipation, evaluation, and treatment of neonatal hypoglycemia. Glucose homeostasis in the fetus and neonate is a developmentally regulated dynamic process involving a number of intricate physiologic mechanisms. In addition, the determination of glucose concentrations is dependent upon both the type of tissue analyzed and the limitations of the specific method employed. The complexity of glucose metabolism makes it difficult to precisely define "normal" and "abnormal" glucose levels in preterm and term neonates.

Survey of the definition and screening of neonatal hypoglycaemia in Australia

OBJECTIVE

To determine the approach to identifying neonatal hypoglycaemia and the definition of neonatal hypoglycaemia used by neonatal paediatricians in Australian Level 3 neonatal intensive care units (NICU).

METHODOLOGY

A questionnaire was sent to the 101 neonatal paediatricians in the 22 Level 3 NICU in Australia asking their method of screening for, and definition of, neonatal hypoglycaemia.

RESULTS

Responses were received from 70 neonatal paediatricians, including all 22 directors. A bedside glucose meter is used in 19 of 22 NICU to screen for hypoglycaemia, whilst one NICU uses a glucose analyzer and another NICU uses a visual colour comparison method. One NICU does not screen, but has blood glucose measured in a satellite laboratory. If the screening method suggests hypoglycaemia, 62 of 63 neonatal paediatricians proceed to blood glucose determination in a laboratory, mostly using plasma samples. Based on the laboratory measurement, the definition of neonatal hypoglycaemia ranged from < 1.1 to 3.0 mmol/L.

CONCLUSIONS

The majority of neonatal paediatricians in Australian NICU screen for neonatal hypoglycaemia using a bedside glucose meter. There is a wide range in the definition of neonatal hypoglycaemia from < 1.1 to 3.0 mmol/L.

Low birthweight infants and total parenteral nutrition immediately after birth. II. Randomised study of biochemical tolerance of intravenous glucose, amino acids, and lipid

This randomised study aimed to compare the biochemical tolerance of three parenteral regimens administered during the first 48 hours of life. Twenty nine infants were randomised to either: (a) glucose 10%; (b) glucose 10%/amino acids; (c) glucose 10%/amino acids/lipid. Blood samples for plasma amino acid profiles, cholesterol, and triglyceride concentrations were taken on arrival in the neonatal unit and again between 36 and 48 hours of life. Arterial or capillary blood gas analysis and blood glucose estimates were performed routinely during the first 48 hours of life. There was a sharp decline in plasma amino acid concentrations in the group following (a) compared with the two groups following (b) and (c) regimens. In all groups plasma triglyceride and cholesterol were not significantly different before and after 48 hours of lipid infusion. Peak mean (SE) bilirubin concentrations (203 (12) v 181 (19) v 220 (20) mumol/l) and the need for phototherapy (nine v eight v five infants) were similar for each of the groups. Hypoglycaemia occurred most frequently during the (b) regimen and least commonly in the (c) group. There are potential health gains from giving parenteral nutrition to low birthweight infants immediately after birth, and this study indicates that restriction of nutritional intake immediately after birth in preterm infants may cause significant metabolic disturbance. This can be prevented by starting a regimen of intravenous amino acids and lipid immediately after birth.

Metabolic adaptation in IUGR neonates determined with microdialysis--a pilot study

Subcutaneous microdialysis was used to monitor the immediate metabolic changes with respect to glucose, glycerol and lactate in the extracellular space of adipose tissue among five small-for-gestational-age (SGA) and two appropriate-for-gestational-age (AGA) newborns. There was a good correlation between glucose levels in blood and dialysate (r = 0.97, n = 14). The infants showed rapid rises and falls in dialysate glucose levels that are not seen among older children and adults. The levels of lactate were higher than those reported in blood. Lactate may serve as an alternative source of energy for the neonate. Microdialysis is of potential value in increasing our understanding of metabolic events. It provides a safe on-line means of making continuous measurements in these fragile patients in order to detect periods of hypoglycaemia, at least in infants with a birth weight > 1000 g.