Continuous glucose monitoring in infants of very low birth weight

Glucose disturbances in very low-birthweight infants-Results from the prospective LIGHT study

AIM

To describe glucose homeostasis disturbances (dysglycaemia) in very low-birthweight infants (<1500 g) during the admission period and explore associated risk factors.

METHODS

The LIGHT (very low-birthweight infants - glucose and hormonal profile over time) study was a prospective observational cohort study that included 49 very low-birthweight infants admitted to the tertiary neonatal intensive care unit in Umeå, Sweden, during 2016-2019. All glucose concentrations (n = 3515) sampled during the admission period were registered.

RESULTS

Hyperglycaemia >10 mmol/L and hypoglycaemia <2.6 mmol/L were registered in 63% and 55% of the infants, respectively. Onset of dysglycaemia occurred almost exclusively in the first postnatal week. Hyperglycaemia followed 15% of corticosteroid doses given; all were preceded by pre-existing hyperglycaemia. Pre-existing hyperglycaemia was found in 66.7% of hyperglycaemic infants who received inotrope treatment. Upon commencement, 72.5% of antimicrobial treatments given were neither preceded nor followed by hyperglycaemia.

CONCLUSION

Dysglycaemia was common in very low-birthweight infants. Daily means of glucose concentrations seemed to follow a postmenstrual age-dependent pattern, decreasing towards term age suggesting a postmenstrual age-dependent developmental mechanism. The primary mechanism causing hyperglycaemia was independent of sepsis, and corticosteroid and inotrope treatments. No hypoglycaemia was registered during ongoing insulin treatment.

The Utility and Safety of a Continuous Glucose Monitoring System (CGMS) in Asphyxiated Neonates during Therapeutic Hypothermia

BACKGROUND

The present study was designed to assess the feasibility and reliability of a Continuous Glucose Monitoring System (CGMS) in a population of asphyxiated neonates during therapeutic hypothermia.

METHODS

This non-randomized feasibility study was conducted in the Neonatal Intensive Care Unit (NICU) facilities of Fondazione Policlinico A. Gemelli IRCSS. Infants matching the criteria for hypothermic treatment were included in this study and were connected to the CGMS (Medtronic, Northridge, CA, USA) within the first 12 h of life. Hypoglycemia was defined as a glucose value ≤ 47 mg/dL, and hyperglycemia was defined as a glucose value ≥ 180 mg/dL. Data obtained via the CGMS were compared with those obtained via a point-of-care blood glucometer (GTX).

RESULTS

The two measuring techniques were compared using the Modified Clarke Error Grid (MCEG). Sixteen infants were enrolled. The sensor had an average (standard deviation) duration of 93 (38) h. We collected 119 pairs of glycemia values (CGMVs) from the CGMS vs. GTX measurements. The CGMS detected twenty-five episodes of hypoglycemia and three episodes of hyperglycemia. All the CGMVs indicating hyperglycemia matched with the blood sample taken via the point-of-care glucometer.

CONCLUSIONS

The use of a CGMS would be useful as it could detect more episodes of disglycemia than standard care. Our data show poor results in terms of the accuracy of the CGMS in this particular setting.

Prevention of Chronic Morbidities in Extremely Premature Newborns with LISA-nCPAP Respiratory Therapy and Adjuvant Perinatal Strategies

Less invasive surfactant administration techniques, together with nasal continuous airway pressure (LISA-nCPAP) ventilation, an emerging noninvasive ventilation (NIV) technique in neonatology, are gaining more significance, even in extremely premature newborns (ELBW), under 27 weeks of gestational age. In this review, studies on LISA-nCPAP are compiled with an emphasis on short- and long-term morbidities associated with prematurity. Several perinatal preventative and therapeutic investigations are also discussed in order to start integrated therapies as numerous organ-saving techniques in addition to lung-protective ventilations. Two thirds of immature newborns can start their lives on NIV, and one third of them never need mechanical ventilation. With adjuvant intervention, these ratios are expected to be increased, resulting in better outcomes. Optimized cardiopulmonary transition, especially physiologic cord clamping, could have an additively beneficial effect on patient outcomes gained from NIV. Organ development and angiogenesis are strictly linked not only in the immature lung and retina, but also possibly in the kidney, and optimized interventions using angiogenic growth factors could lead to better morbidity-free survival. Corticosteroids, caffeine, insulin, thyroid hormones, antioxidants, N-acetylcysteine, and, moreover, the immunomodulatory components of mother's milk are also discussed as adjuvant treatments, since immature newborns deserve more complex neonatal interventions.

Accuracy to detect neonatal hyperglycaemia using real-time continuous glucose monitoring during postoperative period

Identifying hyperglycaemia during postoperative period is essential for neonates. The objective of the study was to analyse the accuracy and reliability of continuous glucose monitoring (CGM) device for detecting hyperglycaemia during postoperative period in neonates. In this prospective study, hourly glucose recordings by CGM device and six hourly by glucometer glucose (GG-reference test for patient management) were collected in ten surgical neonates during first three postoperative days. Mean absolute relative difference (MARD) and proportion of CGM values within ± 15%/15 mg/dL, ± 20%/20 mg/dL, and ± 30%/30 mg/dL of GG, were analysed from matched pair CGM and GG recordings. The diagnostic performance of CGM for neonatal hyperglycaemia (> 150 mg/dL) was expressed as sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV); and the clinical reliability was assessed in Clarke Error Grid Analysis. A total of 720 CGM glucose readings, 120 matched -paired glucose readings by CGM --GG, and 37 episodes were hyperglycaemia by GG. The MARD was 10.76 %; the percentages of glucose readings within 15%/15 mg/dL, 20%/20 mg/dL, and 30%/30 mg/dL were 94.6%, 97.3% and 100% during the hyperglycaemia period. The sensitivity, specificity, PPV and NPV to detect hyperglycaaemia by CGM device were 100%, 93.9%, 88% and 100 % respectively. In Clarke Error Grid Analysis, 97.3 % points were in zone A and B during the hyperglycaemia period.

CONCLUSION

CGM device can be a clinically reliable tool for hyperglycaemia management during postoperative period in neonates.

WHAT IS KNOWN

• Neonates are vulnerable for hyperglycaemia during post-operative period and bed side glucometers are used for frequent glucose monitoring in them. • Continuous glucose monitor(CGM) devices are used for the glucose monitoring in adult and paediatric diabetes care.

WHAT IS NEW

• For the first time, this study analysed the accuracy and clinical reliability of FreeStyle Libre (CGM device) for identifying hyperglycaemia during post-operative period in neonates. • CGM device has very good accuracy for detecting hyperglycaemia in neonates, it may help the clinician for better glucose stability during post-operative period.

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.

Safety and feasibility of a factory-calibrated continuous glucose monitoring system in term and near-term infants at risk of hypoglycemia

Objective

Hypoglycemia increases the risk of adverse neurological outcomes in neonates. Adequate glucose monitoring requires repetitive and painful blood sampling. We aimed to evaluate the feasibility and accuracy of a continuous glucose monitoring system (CGMS) using factory-calibrated sensors to improve glucose monitoring and decrease the frequency of blood samples in neonates.

Material and Methods

A methodological study was conducted to investigate a correlation of CGMS values with blood glucose measurements.

Results

Factory-calibrated CGMS sensors were placed on 21 infants at risk of hypoglycemia after delivery. CGMS values were compared with blood glucose concentrations. Thirty-seven pairs of CGMS and blood glucose values were obtained. There was a good correlation between CGMS and blood glucose values (R=0.67, p<0.01) with a mean difference (2 standard deviations) of 9.78 (-24.68 to 44.25) mg/dL. The mean differences at <3 hours and ≥3 hours after sensor placement were 17.35 (-4.54 to 39.21) mg/dL and 0.88 (-37.62 to 39.38) mg/dL, respectively. CGMS values were significantly higher than blood glucose concentration at <3 hours after sensor placement (p<0.01), whereas no significant differences in glucose values were observed between the CGMS and blood glucose values at ≥3 hours after sensor placement (p=0.852).

Conclusion

The factory-calibrated CGMS was a safe and feasible modality for glucose monitoring. However, it has a tendency to overestimate the blood glucose concentrations. Therefore, this system should be used cautiously for neonates at risk of hypoglycemia, especially within 3 hours after sensor placement.

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.

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.

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.

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.

Recent Advances in Neonatal Diabetes

Neonatal diabetes mellitus (DM) is defined by the onset of persistent hyperglycemia within the first six months of life but may present up to 12 months of life. A gene mutation affecting pancreatic beta cells or synthesis/secretion of insulin is present in more than 80% of the children with neonatal diabetes. Neonatal DM can be transient, permanent, or be a component of a syndrome. Genetic testing is important as a specific genetic mutation can significantly alter the treatment and outcome. Patients with mutations of either KCNJ11 or ABCC8 that encode subunits of the K_ATP channel gene mutation can be managed with sulfonylurea oral therapy while patients with other genetic mutations require insulin treatment.

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.

Neonatal Hyperglycemia, which threshold value, diagnostic approach and treatment?: Turkish Neonatal and Pediatric Endocrinology and Diabetes Societies consensus report

Hyperglycemia has become an important risk factor for mortality and morbidity in the neonatal period, especially with increased survival rates of very low birth weight neonates. Hyperglycemia in the neonatal period develops as a result of various mechanisms including iatrogenic causes, inability to supress hepatic glucose production, insulin resistance or glucose intolerance, specifically in preterm neonates. Initiation of parenteral or enteral feeding in the early period in preterm babies increases insulin production and sensitivity. The plasma glucose is targeted to be kept between 70 and 150 mg/dL in the newborn baby. While a blood glucose value above 150 mg/dL is defined as hyperglycemia, blood glucose values measured with an interval of 4 hours of >180-200 mg/dL and +2 glucosuria require treatment. Although glucose infusion rate is reduced in treatment, use of insulin is recommended, if two blood glucose values measured with an interval of 4 hours are >250 mg/dL and glucosuria is present in two separate urine samples.

Hyperglycemia in Extremely Preterm Infants-Insulin Treatment, Mortality and Nutrient Intakes

OBJECTIVE

To explore the prevalence of hyperglycemia and the associations between nutritional intakes, hyperglycemia, insulin treatment, and mortality in extremely preterm infants.

STUDY DESIGN

Prospectively collected data from the Extremely Preterm Infants in Sweden Study (EXPRESS) was used in this study and included 580 infants born <27 gestational weeks during 2004-2007. Available glucose measurements (n = 9850) as well as insulin treatment and nutritional data were obtained retrospectively from hospital records for the first 28 postnatal days as well as 28- and 70-day mortality data.

RESULTS

Daily prevalence of hyperglycemia >180 mg/dL (10 mmol/L) of up to 30% was observed during the first 2 postnatal weeks, followed by a slow decrease in its occurrence thereafter. Generalized additive model analysis showed that increasing parenteral carbohydrate supply with 1 g/kg/day was associated with a 1.6% increase in glucose concentration (P < .001). Hyperglycemia was associated with more than double the 28-day mortality risk (P < .01). In a logistic regression model, insulin treatment was associated with lower 28- and 70-day mortality when given to infants with hyperglycemia irrespective of the duration of the hyperglycemic episode (P < .05).

CONCLUSIONS

Hyperglycemia is common in extremely preterm infants throughout the first postnatal month. Glucose infusions seem to have only a minimal impact on glucose concentrations. In the EXPRESS cohort, insulin treatment was associated with lower mortality in infants with hyperglycemia. Current practices of hyperglycemia treatment in extremely preterm infants should be reevaluated and assessed in randomized controlled clinical trials.

Continuous glucose monitoring (CGM) in very low birth weight newborns needing parenteral nutrition: validation and glycemic percentiles

Background

Continuous glucose monitoring using subcutaneous sensors is useful in the management of glucose control in neonatal intensive care. We evaluated feasibility and reliability of a continuous glucose monitoring system in a population of very low birth weight neonates needing parenteral nutrition. Moreover, we presented percentiles of glycemia of the studied population.

Methods

Very low birth weight neonates were enrolled within 24 h from birth. An ENLITE sensor connected to a continuous glucose monitoring system was inserted and maintained for at least 72 h. Data obtained with the continuous glucose monitoring system and with a glucometer were compared. Calibration was performed every 12 h.

Results

Twenty-three patients (9 males) were included. Median gestational age was 28 weeks (range 23–30) and median birth weight was 860 g (range 500–1092). A total of 299 paired glucose values were obtained. Modified Clarke Error Grid criteria for clinical significance were met. 74 and 33 episodes of hypoglycemia and hyperglycemia were detected, respectively. 31,329 values of glycemia were analyzed and the percentiles calculated.

Conclusions

This continuous glucose monitoring system is safe and accurate. It allows increasing the detection of hypo- and hyper-glycaemia episodes and it could be routinely used in the management of glucose infusion in very low birth weight neonates under total parenteral nutrition.

Neonatal Diabetes Mellitus: An Update on Diagnosis and Management

Neonatal diabetes mellitus is likely to be due to an underlying monogenic defect when it occurs at less than 6 months of age. Early recognition and urgent genetic testing are important for predicting the clinical course and raising awareness of possible additional features. Early treatment of sulfonylurea-responsive types of neonatal diabetes may improve neurologic outcomes. It is important to distinguish neonatal diabetes mellitus from other causes of hyperglycemia in newborns. Other causes include infection, stress, inadequate pancreatic insulin production in preterm infants, among others. This review explores the diagnostic approach, mutation types, management, and clinical course of neonatal diabetes.

Fluctuation of blood glucose levels in an infant with an ileostomy on continuous glucose monitoring: A case report

Infants with an ileostomy can be at high risk of hypoglycemia because of inadequate nutritional intake; however, there are no reports investigating blood glucose (BG) in infants with ileostomy. We experienced a case of an extremely low birth weight infant who was born at 24 wk of gestation and weighted 623 g. He received an ileostomy because of an intestinal perforation. After the ileostomy, he had recurrent hypoglycemia. Continuous glucose monitoring showed fluctuation of BG levels (postprandial BG elevations and subsequent declines) and non-fasting hypoglycemia, which were undetectable with intermittent fasting BG measurement. The fluctuation of BG levels and non-fasting hypoglycemia improved after closure of the ileostomy. Patients with ileostomy may present with hypoglycemia that is undetectable with intermittent fasting BG measurement. In this case, continuous glucose monitoring was very useful for detecting fluctuation of BG levels and hypoglycemic episodes. Therefore, we recommend that continuous glucose monitoring be performed in infants with an ileostomy to confirm whether they have hypoglycemia or a fluctuation in BG levels. Further studies on the postprandial dynamics of various hormones in infants with ileostomy are required.

Preterm Glycosuria - New Data from a Continuous Glucose Monitoring System

BACKGROUND

Careful control of glucose homeostasis is essential for infants with very low birth weight (VLBW). In clinical practice, blood and urine glucose levels are monitored; however, their correlation has not been fully investigated in VLBW infants.

OBJECTIVES

To evaluate the correlation between interstitial fluid glucose concentration (ISFG), glycosuria, and urine output among VLBW infants through continuous glucose monitoring (CGM).

METHODS

A prospective, single-center, open cohort study enrolled 74 VLBW infants with a mean birth weight of 1,066 g. CGM (Guardian Real-Time CGM®; Medtronic, Northridge, CA, USA) was used to measure glucose. The urine output was calculated using 4-hour intervals. Reagent strips were used for semiquantitative measurement of glycosuria.

RESULTS

The CGM delivered 102,334 glucose measurements. 2,684 urine samples were checked for glycosuria, of which 92.06% remained negative. Corresponding glycemia in samples without glycosuria remained normoglycemic (median 103 mg/dL; 10-90th percentile 80-144 mg/dL). The median glucose concentrations for samples in ascending glycosuria categories 1+, 2+, 3+, and 4+ were 152, 181, 214, and 222 mg/dL, respectively. A moderate correlation between ISFG and urine output was found for categories ≥1+ (rs = 0.56; 95% confidence interval 0.42-0.68; p < 0.001). The urine output was significantly lower when glycosuria was absent (p < 0.05). Polyuria was observed only in glycosuria 4+ (median urine output 9.9; interquartile range 7.4-12.2 mL/kg/h).

CONCLUSIONS

The renal glucose threshold in VLBW infants is between 150 and 180 mg/dL. A negative result for glycosuria is a reliable screening test to exclude hyperglycemia. Occurrence of glycosuria ≥1+ is an indication to test blood glucose.

Continuous glucose monitoring in neonates: a review

Continuous glucose monitoring (CGM) is well established in the management of diabetes mellitus, but its role in neonatal glycaemic control is less clear. CGM has provided important insights about neonatal glucose metabolism, and there is increasing interest in its clinical use, particularly in preterm neonates and in those in whom glucose control is difficult. Neonatal glucose instability, including hypoglycaemia and hyperglycaemia, has been associated with poorer neurodevelopment, and CGM offers the possibility of adjusting treatment in real time to account for individual metabolic requirements while reducing the number of blood tests required, potentially improving long-term outcomes. However, current devices are optimised for use at relatively high glucose concentrations, and several technical issues need to be resolved before real-time CGM can be recommended for routine neonatal care. These include: 1) limited point accuracy, especially at low or rapidly changing glucose concentrations; 2) calibration methods that are designed for higher glucose concentrations of children and adults, and not for neonates; 3) sensor drift, which is under-recognised; and 4) the need for dynamic and integrated metrics that can be related to long-term neurodevelopmental outcomes. CGM remains an important tool for retrospective investigation of neonatal glycaemia and the effect of different treatments on glucose metabolism. However, at present CGM should be limited to research studies, and should only be introduced into routine clinical care once benefit is demonstrated in randomised trials.

Host-microbiota interaction induces bi-phasic inflammation and glucose intolerance in mice

Objective

Gut microbiota modulates adiposity and glucose metabolism in humans and mice. Here we investigated how colonization of germ-free (GF) mice affects kinetics of adiposity and glucose metabolism.

Methods

Adiposity and glucose metabolism were evaluated at different time points in ex-GF and antibiotic treated mice after colonization with gut microbiota from a conventionally raised (CONV-R) mouse. Mouse physiology, microbiome configuration, serum cytokine levels, and gene expression for inflammatory markers were performed in different tissues.

Results

Colonization resulted in a bi-phasic glucose impairment: the first phase occurring within 3 days of colonization (early phase) and the second 14–28 days after colonization (delayed phase). The early phase co-occurred with an inflammatory response and was independent of adiposity, while the delayed phase was mostly ascribed to adipose tissue expansion and inflammation. Importantly, re-colonization of antibiotic treated mice displays only the delayed phase of glucose impairment and adiposity, suggesting that the early phase may be unique to colonization of the immature GF mice gut.

Conclusions

Our results provide new insights on host–microbiota interaction during colonization of GF mice and the resulting effects on adiposity and glucose metabolism in a time resolved fashion.

•

Inflammation affects glucose tolerance in early phase of colonization of GF mice.

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Adiposity affects glucose tolerance in delayed phase of colonization of GF mice.

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Colonization of antibiotics treated mice show only the delayed phase of glucose impairment.

Early postnatal hyperglycaemia is a risk factor for treatment-demanding retinopathy of prematurity

BACKGROUND

To investigate whether neonatal hyperglycaemia in the first postnatal week is associated with treatment-demanding retinopathy of prematurity (ROP).

METHODS

This is a Danish national, retrospective, case-control study of premature infants (birth period 2003-2006). Three national registers were searched, and data were linked through a unique civil registration number. The study sample consisted of 106 cases each matched with two comparison infants. Matching criteria were gestational age (GA) at birth, ROP not registered and born at the same neonatal intensive care unit. Potential 'new' risk factors were analysed in a multivariate logistic regression model, while adjusted for previously recognised risk factors (ie, GA at birth, small for gestational age, multiple birth and male sex).

RESULTS

Hospital records of 310 preterm infants (106 treated; 204 comparison infants) were available. Nutrition in terms of energy (kcal/kg/week) and protein (g/kg/week) given to the preterm infants during the first postnatal week were statistically insignificant between the study groups (Mann-Whitney U test; p=0.165/p=0.163). Early postnatal weight gain between the two study groups was borderline significant (t-test; p=0.047). Hyperglycaemic events (indexed value) were statistically significantly different between the two study groups (Mann-Whitney U test; p<0.001). Hyperglycaemia was a statistically independent risk factor (OR: 1.022; 95% CI 1.002 to 1.042; p=0.031).

CONCLUSION

An independent association was found between the occurrence of hyperglycaemic events during the first postnatal week and later development of treatment-demanding ROP, when adjusted for known risk factors.

Continuous subcutaneous glucose monitoring is accurate in term and near-term infants at risk of hypoglycaemia

AIM

Postnatal hypoglycaemia increases the risk of adverse neurological outcomes in newborn infants, and adequate glucose control requires repetitive and painful blood sampling. This study evaluated a continuous glucose monitoring system (CGMS) that aims to improve glucose control and decrease the frequency of blood samples taken from neonates.

METHODS

CGMS sensors, which measure glucose values every five minutes and require calibration twice a day, were placed on 20 infants at risk of hypoglycaemia. The infants also underwent blood glucose sampling, and the blood glucose values were compared with CGMS values six times during the first 30 minutes after sampling.

RESULTS

We used 97/264 (37%) of the blood glucose values taken for the CGMS calibration. The highest accuracy, a mean of 0.22 (95% confidence interval 0.13-0.30 mmol/L), was found 15-19 minutes after sampling, due to the calibration process. No significant subcutaneous glucose time lag was detectable.

CONCLUSION

The CGMS system was an accurate and feasible method for glucose control, provided earlier detection of hypoglycaemia in newborn infants and reduced their exposure to procedural pain. The delay in calibration in infants was a new finding and needs to be taken into account when comparing CGMS readings to blood glucose values.

Continuous glucose monitoring in preterm infants: evaluation by a modified Clarke error grid

Background

Continuous glucose monitoring using subcutaneous sensors has been validated in adults and children with diabetes, and was found to be useful in the management of glucose control. We aimed to assess feasibility and reliability of a new continuous glucose monitoring system (CGMS) in a population of preterm neonates using a Clarke error grid (CEG) specifically modified for preterm infants.

Methods

Preterm infants were recruited within 24 h from delivery. A subcutaneous sensor connected to a CGMS was inserted and maintained for 6 days. Data collected from CGMS were compared with data obtained using a glucometer. Management of the infants followed standard protocols and was not influenced by CGMS readings.

Results

Twenty patients (9 males) were included. Median (range) gestational age was 32 weeks (27–36) and median (range) birth weight was 1350 g (860–3360). Average CGMS recording time was 137 h, for a total of 449 paired glucose levels. CEG and modified CEG criteria for clinical significance were met.

Conclusion

CGMS is a safe and clinically adequate method to estimate glucose levels in preterm infants. As the glucose level can be evaluated in real time, this CGMS could be useful to reduce the number of heel sticks, to observe glycaemic trends and to promptly detect episodes of both hypo- and hyper-glycaemia.

Real-time continuous glucose monitoring reduces the duration of hypoglycemia episodes: a randomized trial in very low birth weight neonates

OBJECTIVES

Hypoglycemia is frequent in very low birth weight (VLBW) neonates and compromises their neurological outcome. The aim of this study was to compare real-time continuous glucose monitoring system (RT-CGMS) to standard methods by intermittent capillary blood glucose testing in detecting and managing hypoglycemia.

STUDY DESIGN

Forty-eight VLBW neonates were enrolled in this prospective study. During their 3 first days of life, their glucose level was monitored either by RT-CGMS (CGM-group), or by intermittent capillary glucose testing (IGM-group) associated with a blind-CGMS to detect retrospectively missed hypoglycemia. Outcomes were the number and duration of hypoglycemic (≤ 50 mg/dl) episodes per patient detected by CGMS.

RESULTS

Forty-three monitorings were analyzed (IGM n = 21, CGM n = 22), with a median recording time of 72 hours. In the IGM group, blind-CGMS revealed a significantly higher number of hypoglycemia episodes than capillary blood glucose testing (1.2 ± 0.4 vs 0.4 ± 0.2 episode/patient, p<0.01). In the CGM-group, the use of RT-CGMS made it possible (i) to detect the same number of hypoglycemia episodes as blind-CGMS (1.2 ± 0.4 episode/patient), (ii) to adapt the glucose supply in neonates with hypoglycemia (increased supply during days 1 and 2), and (iii) to significantly reduce the duration of hypoglycemia episodes per patient (CGM 44[10-140] min versus IGM 95[15-520] min, p<0.05). Furthermore, it reduced the number of blood samples (CGM 16.9 ± 1.0 vs IGM 21.9 ± 1.0 blood sample/patient, p<0.001).

CONCLUSION

RT-CGMS played a beneficial role in managing hypoglycemia in VLBW neonates by adjusting the carbohydrate supply to the individual needs and by reducing the duration of hypoglycemia episodes. The clinical significance of the biological differences observed in our study need to be explored.

Instability of glucose values in very preterm babies at term postmenstrual age

OBJECTIVE

To determine if very preterm (VPT) babies are capable of maintaining glucose levels within normal ranges at or near term postmenstrual age.

STUDY DESIGN

Glucose levels were intermittently or continuously monitored during 48 hours in a cohort of 60 VPT infants near hospital discharge. Hypoglycemic (≤45 mg/dL, 2.5 mmol/L) and hyperglycemic (≥140 mg/dL or 7.8 mmol/L, severe if ≥180 mg/dL or 10 mmol/L) episodes were considered relevant if they lasted longer than 30 minutes. Feeding regimes followed current practice.

RESULTS

With intermittent capillary, 2 hypoglycemic values and another 3 that were abnormally high were detected. With continuous monitoring, 6 babies (10.0%) had isolated hypoglycemia ≤45 mg/dL (2.5 mmol/L) (3 of them reaching 40 mg/dL, 2.2 mmol/L), 14 (23.3%) had isolated hyperglycemia, and 8 (13.3%) had episodes of both. The mean duration of hypoglycemia per patient was 2.8 ± 2.9 hours and 4.68 ± 4.35 hours in the case of hyperglycemia, with 12 infants becoming severely hyperglycemic. Of the 12 severely hyperglycemic patients, 5 also developed severe hypoglycemia. No specific characteristics identified the hypoglycemic babies. A history of intrauterine growth restriction (P = .037) and female sex (P = .063) seemed to increase the risk of severe hyperglycemia.

CONCLUSIONS

VPT infants continue to have abnormal glucose values, especially hyperglycemia, by the time of hospital discharge. No specific factors identify babies at higher risk for hypoglycemia, and intrauterine growth restriction and female sex seemed to predispose to hyperglycemia.

A prospective study on hyperglycemia and retinopathy of prematurity

OBJECTIVE

Retinopathy of prematurity (ROP) constitutes a significant morbidity in premature infants that can lead to blindness. Multiple retrospective studies have identified neonatal hyperglycemia as a risk for developing ROP. However, in the absence of any reported prospective study, it is not clear whether hyperglycemia is associated with ROP independent of the commonly associated comorbidities. The objective of this study was to investigate whether hyperglycemia in premature infants is independently associated with ROP.

STUDY DESIGN

Premature infants (<1500 g or⩽32 weeks gestational age) were enrolled in a prospective longitudinal cohort study. All demographic, clinical and laboratory data were collected. Bedside whole-blood glucose concentration was measured every 8 h daily for 7 days. For any glucose reading<50 or>150 mg dl(-1), serum sample was sent to the laboratory for confirmation. Hyperglycemia was defined as any blood glucose level⩾150 mg dl(-1). ROP patients were compared with non-ROP patients in a bivariate analysis. Variables significantly associated with ROP were studied in a logistic regression model.

RESULT

A total of 65 patients were enrolled with gestational age 31.1±1.2 weeks and birth weight 1385±226 g. Thirty-one patients (48%) were identified with hyperglycemia. On eye examination, 19 cases (29.2%) had ROP (13 with stage 1, 4 with stage 2 and 2 with stage 3). There were more cases of ROP in the hyperglycemia group compared with the euglycemia group (45% vs 15%, P=0.007). Patients who developed ROP had significantly higher maximum and average glucose concentrations when compared with non-ROP patients. Multiple factors have been associated with ROP on bivariate analysis, including gestational age, exposure to oxygen, respiratory support and poor weight gain. However, in a logistic regression model including all significant variables, average blood glucose in the first week of life was the factor independently associated with ROP with an odds ratio of: 1.77 (95% confidence interval: 1.08 to 2.86), P=0.024.

CONCLUSION

In a cohort of premature infants, elevated average blood glucose concentrations in the first week of life is independently associated with the development of ROP.

Experience with real time continuous glucose monitoring in stabilising fluctuating glycaemia during intensive care of the preterm infant of a diabetic mother

OBJECTIVE

The newborns of diabetic mothers suffer from perinatal complications more frequently than the newborns of healthy women.

METHODS

We used for 7 days a real time continuous glucose monitoring system (RT-CGMS) to monitor glucose homeostasis and manage glucose administration in a premature newborn of a diabetic mother.

RESULTS

The boy was born at 35 + 5 gestational weeks with typical signs of diabetic fetopathy. RT-CGMS revealed 2 late hypoglycaemia episodes on the 2nd and 4th days. The sensor readings correlated well with glycaemia measured in the laboratory (r = 0.908, p = 0.005). To support conclusions of this case report, we attached the data of five other preterm newborns of diabetic mothers who were later successfully treated according to the RT-CGMS data as well.

CONCLUSIONS

This approach allows timely response to glycaemia instability and is applicable even in preterm infants.

Nocturnal hypoglycaemia in ACTH and GH deficient children: role of continuous glucose monitoring

OBJECTIVES

To evaluate the usefulness of continuous glucose monitoring (CGM) to identify nocturnal hypoglycaemia in children affected by combined ACTH and GH deficiency and to optimize the hydrocortisone replacement therapy in these patients.

STUDY DESIGN

Eleven patients with ACTH and GH deficiency (five boys and six girls, age 1·6-16·8 years) underwent CGM for 36 h, including two nights. At least two consecutive glucose levels <2·78 mm were considered hypoglycaemic episodes. The differences in age and doses of hydrocortisone and recombinant human growth hormone (rhGH) between children with and without hypoglycaemia were analysed. The percentage of the glucose values <3·33 mm and the mean glucose levels were also evaluated.

RESULTS

Continuous glucose monitoring demonstrated nocturnal hypoglycaemia lasting from 30 to 155 min (1·5% of the total monitoring time) in three cases (27%). No statistically significant differences in age and rhGH dose were observed between children with or without hypoglycaemia. Conversely, the difference in the hydrocortisone doses between the patients with and without hypoglycaemia resulted statistically significant (5·9 vs 8·5 mg/m²/day; P = 0·04). Eight patients presented glucose values less than 3·33 mm during 5% of the total monitoring time. Hydrocortisone dose showed significant positive linear relation with mean glucose level (r = 0·79, P = 0·0035) and inverse relation with time lags of glucose levels under 3·33 mm (r = -0·65, P = 0·03).

CONCLUSIONS

Our study shows that CGM may represent a valuable tool to detect nocturnal asymptomatic hypoglycaemic episodes and optimize the hydrocortisone therapeutic regimen in children with ACTH and GH deficiency.

The use of continuous glucose monitoring combined with computer-based eMPC algorithm for tight glucose control in cardiosurgical ICU

AIM

In postcardiac surgery patients, we assessed the performance of a system for intensive intravenous insulin therapy using continuous glucose monitoring (CGM) and enhanced model predictive control (eMPC) algorithm.

METHODS

Glucose control in eMPC-CGM group (n = 12) was compared with a control (C) group (n = 12) treated by intravenous insulin infusion adjusted according to eMPC protocol with a variable sampling interval alone. In the eMPC-CGM group glucose measured with a REAL-Time CGM system (Guardian RT) served as input for the eMPC adjusting insulin infusion every 15 minutes. The accuracy of CGM was evaluated hourly using reference arterial glucose and Clarke error-grid analysis (C-EGA). Target glucose range was 4.4-6.1 mmol/L.

RESULTS

Of the 277 paired CGM-reference glycemic values, 270 (97.5%) were in clinically acceptable zones of C-EGA and only 7 (2.5%) were in unacceptable D zone. Glucose control in eMPC-CGM group was comparable to C group in all measured values (average glycemia, percentage of time above, within, and below target range,). No episode of hypoglycemia (<2.9 mmol) occurred in eMPC-CGM group compared to 2 in C group.

CONCLUSION

Our data show that the combination of eMPC algorithm with CGM is reliable and accurate enough to test this approach in a larger study population.

Incidence of neonatal hypoglycemia in babies identified as at risk

OBJECTIVES

Routine blood glucose screening is recommended for babies at risk of neonatal hypoglycemia. However, the incidence of hypoglycemia in those screened is not well described. We sought to determine the incidence of hypoglycemia in babies identified as being at risk, and also to determine differences in incidence between at risk groups.

STUDY DESIGN

Infants (n = 514) were recruited who were born in a tertiary hospital, ≥35 weeks gestation and identified as at risk of hypoglycemia (small, large, infant of a diabetic, late-preterm, and other). Blood glucose screening used a standard protocol and a glucose oxidase method of glucose measurement in the first 48 hours after birth.

RESULTS

One-half of the babies (260/514, 51%) became hypoglycemic (<2.6 mM), 97 (19%) had severe hypoglycemia (≤2.0 mM), and 98 (19%) had more than 1 episode. The mean duration of an episode was 1.4 hours. Most episodes (315/390, 81%) occurred in the first 24 hours. The median number of blood glucose measurements for each baby was 9 (range 1-22). The incidence and timing of hypoglycemia was similar in all at risk groups, but babies with a total of 3 risk factors were more likely to have severe hypoglycemia.

CONCLUSIONS

Hypoglycemia is common amongst babies recommended for routine blood glucose screening. We found no evidence that screening protocols should differ in different at risk groups, but multiple risk factors may increase severity. The significance of these hypoglycemic episodes for long-term outcome remains undetermined.

Impact of retrospective calibration algorithms on hypoglycemia detection in newborn infants using continuous glucose monitoring

BACKGROUND

Neonatal hypoglycemia is common and may cause serious brain injury. Diagnosis is by blood glucose (BG) measurements, often taken several hours apart. Continuous glucose monitoring (CGM) could improve hypoglycemia detection, while reducing the number of BG measurements. Calibration algorithms convert sensor signals into CGM output. Thus, these algorithms directly affect measures used to quantify hypoglycemia. This study was designed to quantify the effects of recalibration and filtering of CGM data on measures of hypoglycemia (BG <2.6 mmol/L) in neonates.

SUBJECTS AND METHODS

CGM data from 50 infants were recalibrated using an algorithm that explicitly recognized the high-accuracy BG measurements available in this study. CGM data were analyzed as (1) original CGM output, (2) recalibrated CGM output, (3) recalibrated CGM output with postcalibration median filtering, and (4) recalibrated CGM output with precalibration median filtering. Hypoglycemia was classified by number of episodes, duration, severity, and hypoglycemic index.

RESULTS

Recalibration increased the number of hypoglycemic events (from 161 to 193), hypoglycemia duration (from 2.2% to 2.6%), and hypoglycemic index (from 4.9 to 7.1 μmol/L). Median filtering postrecalibration reduced hypoglycemic events from 193 to 131, with little change in duration (from 2.6% to 2.5%) and hypoglycemic index (from 7.1 to 6.9 μmol/L). Median filtering prerecalibration resulted in 146 hypoglycemic events, a total duration of hypoglycemia of 2.6%, and a hypoglycemic index of 6.8 μmol/L.

CONCLUSIONS

Hypoglycemia metrics, especially counting events, are heavily dependent on CGM calibration BG error, and the calibration algorithm. CGM devices tended to read high at lower levels, so when high accuracy calibration measurements are available it may be more appropriate to recalibrate the data.

Care of the infant of the diabetic mother

Gestational diabetes mellitus (GDM) from all causes of diabetes is the most common medical complication of pregnancy and is increasing in incidence, particularly as type 2 diabetes continues to increase worldwide. Despite advances in perinatal care, infants of diabetic mothers (IDMs) remain at risk for a multitude of physiologic, metabolic, and congenital complications such as preterm birth, macrosomia, asphyxia, respiratory distress, hypoglycemia, hypocalcemia, hyperbilirubinemia, polycythemia and hyperviscosity, hypertrophic cardiomyopathy, and congenital anomalies, particularly of the central nervous system. Overt type 1 diabetes around conception produces marked risk of embryopathy (neural tube defects, cardiac defects, caudal regression syndrome), whereas later in gestation, severe and unstable type 1 maternal diabetes carries a higher risk of intrauterine growth restriction, asphyxia, and fetal death. IDMs born to mothers with type 2 diabetes are more commonly obese (macrosomic) with milder conditions of the common problems found in IDMs. IDMs from all causes of GDM also are predisposed to later-life risk of obesity, diabetes, and cardiovascular disease. Care of the IDM neonate needs to focus on ensuring adequate cardiorespiratory adaptation at birth, possible birth injuries, maintenance of normal glucose metabolism, and close observation for polycythemia, hyperbilirubinemia, and feeding intolerance.

Contribution of early glycemic status in the development of severe retinopathy of prematurity in a cohort of ELBW infants

OBJECTIVE

The objective of this study is to investigate the relationship between glycemic status and severe retinopathy of prematurity (ROP).

STUDY DESIGN

This is a retrospective cohort study of 114 infants <1000 g admitted to a level IV neonatal intensive care unit within 48 h of life. A cumulative, time-weighted glucose level (TWGL) derived from plotting glucose values over time was included in logistic regression analysis to identify predictors for severe ROP.

RESULT

Infants had 26.6 ± 2 weeks gestational age and had a birth weight of 782 ± 136 g. TWGL during first 10 and 30 days of life were greater in the severe ROP group (P<0.01). Unlike single events of glucose levels ≥ 150 mg dl(-1), 10 days TWGL ≥ 100 mg dl(-1) (odds ratio (OR) 5.2, P<0.02) and 30 days TWGL ≥ 118 mg dl(-1) (OR 5.7, P<0.02) were predictors for severe ROP (univariate). Multivariate regression confirmed 30 days TWGL ≥ 118 mg dl(-1) (OR 9.4 to 10) and gram-positive sepsis (OR 4.1 to 5) as predictors for severe ROP (P<0.05).

CONCLUSION

High overall glycemic status is associated with the development of severe ROP.

Cot-side electroencephalography monitoring is not clinically useful in the detection of mild neonatal hypoglycemia

OBJECTIVES

To determine whether there is a relationship between electroencephalography patterns and hypoglycemia, by using simultaneous cot-side amplitude integrated electroencephalography (aEEG) and continuous interstitial glucose monitoring, and whether non-glucose cerebral fuels modified these patterns.

STUDY DESIGN

Eligible babies were ≥ 32 weeks gestation, at risk for hypoglycemia, and admitted to the neonatal intensive care unit. Electrodes were placed in C3-P3, C4-P4 O1-O2 montages. A continuous interstitial glucose sensor was placed subcutaneously, and blood glucose was measured by using the glucose oxidase method. Non-glucose cerebral fuels were measured at study entry, exit, and during recognized hypoglycemia.

RESULTS

A total of 101 babies were enrolled, with a median weight of 2179 g and gestation of 35 weeks. Twenty-four of the babies had aEEG recordings, and glucose concentrations were low (< 2.6 mM). There were 103 episodes of low glucose concentrations lasting 5 to 475 minutes, but no observable changes in aEEG variables. Plasma concentrations of lactate, beta-hydroxybutyrate, and glycerol were low and did not alter during hypoglycemia.

CONCLUSIONS

Cot-side aEEG was not useful for the detection of neurological changes during mild hypoglycemia. Plasma concentrations of non-glucose cerebral fuels were low and unlikely to provide substantial neuroprotection.

Higher glycemic variability in very low birth weight newborns is associated with greater early neonatal mortality

OBJECTIVE

To determine the association between mean glycemia and its variability with perinatal mortality in preterm newborns hospitalized in an intensive care unit (ICU).

METHODS

Patients admitted to the ICU within the first 12 hours of life, with birth weight <1500 g, at least three blood glucose measurements/day and lack of insulin treatment were evaluated. Association of mean glycemia and its standard deviation (SD) with death during initial 7 days of life was evaluated. Multivariate logistic regression analysis was performed twice, using continuous glucose concentrations and by means of a quintile-based approach correcting for nonnormal distribution and nonlinear effects.

RESULTS

A total of 95 newborns were enrolled. Eleven patients (11.5%) died during the initial 7 days of life, overall mortality equaled 22%. Multivariate analysis showed that 5 minute Apgar score and SD of glucose concentrations were significantly associated with increased mortality in both models. Odds ratios (ORs) equaled 0.44; 95% confidence interval (95% CI) 0.27-0.74 and OR 1.34; 95% CI 1.03-2.03 for the continuous model and 0.50 95% CI 0.34-0.75 and OR 1.82 95% CI 1.07-3.11 for the quintile-based model. In both cases, mean glycemia was removed during the stepwise model-building procedure.

CONCLUSIONS

Higher glycemic variability may be associated with greater odds of perinatal mortality.

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.

Continuous glucose monitoring in newborn babies at risk of hypoglycemia

OBJECTIVE

To determine the usefulness of continuous glucose monitoring in babies at risk of neonatal hypoglycemia.

STUDY DESIGN

Babies >/=32 weeks old who were at risk of hypoglycemia and admitted to newborn intensive care received routine treatment, including intermittent blood glucose measurement using the glucose oxidase method, and blinded continuous interstitial glucose monitoring.

RESULTS

Continuous glucose monitoring was well tolerated in 102 infants. There was good agreement between blood and interstitial glucose concentrations (mean difference, 0.0 mmol/L; 95% CI, -1.1-1.1). Low glucose concentrations (<2.6 mmol/L) were detected in 32 babies (32%) with blood sampling and in 45 babies (44%) with continuous monitoring. There were 265 episodes of low interstitial glucose concentrations, 215 (81%) of which were not detected with blood glucose measurement. One hundred seven episodes in 34 babies lasted >30 minutes, 78 (73%) of which were not detected with blood glucose measurement.

CONCLUSION

Continuous interstitial glucose monitoring detects many more episodes of low glucose concentrations than blood glucose measurement. The physiological significance of these previously undetected episodes is unknown.

Short and long term outcome of neonatal hyperglycemia in very preterm infants: a retrospective follow-up study

Background

Hyperglycemia in premature infants is associated with increased morbidity and mortality, but data on long-term outcome are limited. We investigated the effects of neonatal hyperglycemia (blood glucose ≥ 10 mmol/l, treated with insulin for ≥ 12 hours) on growth and neurobehavioral outcome at 2 years of age.

Methods

Retrospective follow-up study at 2 years of age among 859 infants ≤32 weeks of gestation admitted to a tertiary neonatal center between January 2002 and December 2006. Thirty-three survivors treated with insulin for hyperglycemia and 63 matched controls without hyperglycemia were evaluated at a corrected age of 2 years. Outcome measures consisted of growth (weight, length, and head circumference) and neurological and behavioural development.

Results

66/859 (8%) infants ≤ 32 weeks of gestation developed hyperglycemia. Mortality during admission was 27/66 (41%) in the hyperglycemia group versus 62/793 (8%) in those without hyperglycemia (p < 0.001). Mortality was higher in infants with hyperglycemia with a birth weight ≤1,000 gram (p = 0.005) and/or gestational age of 24-28 weeks (p = 0.009) than in control infants without hyperglycemia. Sepsis was more prominent in infants with hyperglycemia and a birth weight of >1,000 gram (p = 0.002) and/or gestational age of 29-32 weeks (p = 0.009) than in control infants without hyperglycemia. Growth at 2 years of age was similar, but neurological and behavioural development was more frequently abnormal among those with neonatal hyperglycemia (p = 0.036 and 0.021 respectively).

Conclusions

Mortality was higher in very preterm infants with hyperglycemia treated with insulin during the neonatal period. At 2 years of age survivors showed normal growth, but a higher incidence of neurological and behavioural problems. Better strategies to manage hyperglycemia may improve outcome of very preterm infants.