Does hyperglycemia in hypernatremic preterm infants increase the risk of intraventricular hemorrhage?

Management of Neonatal Hyperglycaemia in Sweden-A Survey Study

AIM

Neonatal hyperglycaemia is associated with a multitude of adverse outcomes, including mortality and impaired neurological development. The aim of this study was to characterise the current management of neonatal hyperglycaemia in Swedish neonatal units.

METHODS

A digital survey was sent to 27 Swedish neonatal units providing care to preterm infants born before 32 completed gestational weeks.

RESULTS

Sixty-eight responses were collected from 21 different units. Thirty-two percent (22/68) of clinicians reported having a local treatment guideline for neonatal hyperglycaemia. Hyperglycaemia was defined as a glucose concentration above a value in the range of 8.0-10.0 mmol/L by 62.5% of clinicians, while 16.7% and 21.8% used a definition between 10.1 and 12.0 mmol/L and > 12 mmol/L, respectively. Intravenous glucose reduction was initiated at higher glucose concentrations by clinicians working at university hospital units (p = 0.006). Glucose concentration threshold for initiation of insulin treatment varied between 8 and 30 mmol/L. Three clinicians (3/35 (8.5%)) reported having experienced problems with frequent hypoglycaemia during ongoing insulin treatment.

CONCLUSIONS

This study demonstrates extensive differences in clinical practice regarding neonatal hyperglycaemia both within and between neonatal units in Sweden. Randomised controlled trials are needed to provide evidence for clinical guidelines and to improve and standardise the care of these infants.

Thermoregulation, incubator humidity, and skincare practices in appropriate for gestational age ultra-low birth weight infants: need for more evidence

BACKGROUND

Although not universal, active care is being offered to infants weighing < 500 g at birth, referred to as ultra-low birth weight (ULBW) infants appropriate for gestational age. These infants have the greatest risk of dying or developing major morbidities. ULBW infants face challenges related to fluid and heat loss as well as skin injury in the initial days of life from extreme anatomical and physiological immaturity of the skin. Although there is an emerging literature on the outcomes of ULBW infants, there is a paucity of evidence to inform practice guidelines for delivering optimal care to this cohort of infants.

DATA SOURCES

A comprehensive review of the literature was performed using the PubMed and Embase databases. Searched keywords included "thermoregulation or body temperature regulation", "incubator humidity", "skin care", "infant, extremely low birth weight" and "ultra-low birth weight infants".

RESULTS

Evidences for thermoregulation, incubator humidity, and skincare practices are available for preterm infants weighing < 1500 g at birth but not specifically for ULBW infants. Studies on thermoregulation, incubator humidity, or skincare practices had a small sample size and did not include a sub-group analysis for ULBW infants. Current practice recommendations in ULBW infants are adopted from research in very and/or extremely low birth weight infants.

CONCLUSIONS

This narrative review focuses on challenges in thermoregulation, incubator humidity, and skincare practices in ULBW infants, highlights current research gaps and suggests potential developments for informing practices for improving health outcomes in ULBW infants. Video abstract (MP4 1,49,115 kb).

Effects of Total Parenteral Nutrition on Serum Osmolality and Patent Ductus Arteriosus

BACKGROUND

The persistence of high serum osmolality in the early postnatal period is a risk for developing patent ductus arteriosus (PDA). Early aggressive nutrition (EAN), involving total parenteral nutrition (TPN), by which enough concentrations of glucose and amino acids are administered intravenously, is recommended postnatally to improve the neurological prognosis in preterm infants. However, the effects of EAN involving TPN on serum osmolality and the development of a PDA have not been adequately studied.

OBJECTIVES

Thus, in this study, we aimed to investigate the impact of TPN on serum osmolality and determine whether increased serum osmolality could be associated with a higher incidence of PDA in preterm infants.

METHODS

In this single-center retrospective observational study, preterm infants born at <28 weeks of gestation who had been admitted to our neonatal intensive care unit (NICU) before (pre-TPN period) and after the introduction of TPN (post-TPN) were included. We reviewed the medical records of these patients, compared the changes in serum osmolality from birth to five days after birth, the clinical background, and the incidence of PDA between these two periods, and analyzed the risk factors. Additionally, the factors affecting the serum osmolality in very preterm infants were examined. The patients who met the intervention criteria of our NICU and received a cyclooxygenase (COX) inhibitor, Indacin® (Nobelpharma, Tokyo, Japan), within seven days after birth were classified as PDA+; those who could not be identified to have PDA flow by echo and did not receive a COX inhibitor were classified as PDA-.

RESULTS

The postnatal day and serum sodium (Na+) were statistically significantly correlated with a higher serum osmolality. Serum osmolality remained statistically significantly higher in the PDA+ cohort compared with the PDA- cohort after the first day of life. However, no statistically significant differences were observed in serum osmolality after 24 hours of age, weeks of gestational age, birth weight, or incidence of PDA between the pre- and post-TPN periods. The results of the multiple logistic regression analyses revealed that the increased serum osmolality correlated with PDA development.

CONCLUSIONS

In this study, the serum Na+ statistically significantly correlated with a higher serum osmolality. Moreover, the increased serum osmolality correlated with PDA development. Thus, the prevention of hypernatremia might reduce the incidence of PDA. Nonetheless, the findings in this study revealed that no statistically significant differences in serum osmolality were observed between the pre-and post-TPN periods, indicating that TPN had little effect on serum osmolality.

Hypernatremia in Hyperglycemia: Clinical Features and Relationship to Fractional Changes in Body Water and Monovalent Cations during Its Development

In hyperglycemia, the serum sodium concentration ([Na]S) receives influences from (a) the fluid exit from the intracellular compartment and thirst, which cause [Na]S decreases; (b) osmotic diuresis with sums of the urinary sodium plus potassium concentration lower than the baseline euglycemic [Na]S, which results in a [Na]S increase; and (c), in some cases, gains or losses of fluid, sodium, and potassium through the gastrointestinal tract, the respiratory tract, and the skin. Hyperglycemic patients with hypernatremia have large deficits of body water and usually hypovolemia and develop severe clinical manifestations and significant mortality. To assist with the correction of both the severe dehydration and the hypovolemia, we developed formulas computing the fractional losses of the body water and monovalent cations in hyperglycemia. The formulas estimate varying losses between patients with the same serum glucose concentration ([Glu]S) and [Na]S but with different sums of monovalent cation concentrations in the lost fluids. Among subjects with the same [Glu]S and [Na]S, those with higher monovalent cation concentrations in the fluids lost have higher fractional losses of body water. The sum of the monovalent cation concentrations in the lost fluids should be considered when computing the volume and composition of the fluid replacement for hyperglycemic syndromes.

A Higher Amount of Nutritional Intake as a Possible Cause of Hyperglycemia in Extremely Premature Infants in Parenteral and Enteral Nutrition at the Tertiary Neonatal Intensive Care Unit

BACKGROUND

This study aimed to find an association between infants who had hyperglycemia and those who did not, those treated with insulin or not and several prenatal and postnatal variables or the suboptimal prescription of parenteral nutrition.

METHODS

We conducted a retrospective study, which included extremely premature infants (<28 weeks of gestation) admitted to the tertiary NICU, University Medical Centre Ljubljana, between 1 January 2021 and 31 December 2021. Blood glucose measurements, insulin treatment, general characteristics, nutritional data and complications of prematurity were obtained retrospectively from hospital data.

RESULTS

There were 21 infants included in the study who did not receive insulin and 17 who were treated with insulin. Infants receiving insulin were younger and lighter compared to the non-insulin treatment group (mean gestational age 178 vs. 188 days; median birth weight 680 g vs. 990 g). The younger insulin group of infants received the same daily number of total macronutrients per kg per day compared to the older non-insulin group, i.e., glucose, lipids and amino acids, as recommended for the gestational age and birth weight. After adjusting for gestational age, no significant association with complications of prematurity was found.

CONCLUSIONS

The postulated explanation (with the prescription of a higher amount of macronutrients during the first seven days) for hyperglycemia and treatment with insulin in the less mature and lighter infants cannot be supported by the data given.

Risk factors for periventricular-intraventricular haemorrhage severity in preterm infants: a propensity score-matched analysis

BACKGROUND

Most previous studies comparing etiological studies in infants with and without periventricular-intraventricular haemorrhage (PV-IVH) concluded that younger gestational age (GA) was associated with a higher prevalence rate of PV-IVH. However, only a few studies have examined the risk factors associated with the severity of PV-IVH after removing the influence of GA. Therefore, we investigated the risk factors apart from GA for PV-IVH severity in preterm infants less than 28 weeks.

METHODS

This was a retrospective case-control study of preterm infants born in West China Second Hospital with PV-IVH between 2009 and 2020. PV-IVH was defined using cranial ultrasound screening. Preterm infants were divided into no PV-IVH and PV-IVH groups, and preterm infants with PV-IVH were divided into mild and severe PV-IVH groups. Groups were matched in a 1:1 ratio using propensity score calculated from GA. Variables were collected from infant-mother pairs. A stepwise forward multivariate logistic regression model was adopted to select factors that affected PV-IVH in preterm infants.

RESULTS

A total of 429 preterm infants were included. The total incidence of PV-IVH in preterm infants was 55.6%, and the incidence of mild and severe PV-IVH was 28.7% and 26.9%, respectively. We matched 162 infants with no PV-IVH with 162 infants with PV-IVH. The results suggested that electrolyte disorder (OR 2.79, 95% CI: 1.34-5.77), early-onset sepsis (OR 1.76, 95% CI: 1.01-3.08), thrombocytopenia (OR 2.87, 95% CI: 1.10-7.48), invasive mechanical ventilation (OR 4.21, 95% CI: 1.86-9.55), and male sex (OR 2.16, 95% CI: 1.29-3.60) were independently associated with PV-IVH. Then, we matched 87 infants with mild PV-IVH with 87 infants with severe PV-IVH. The results suggested that electrolyte disorder (OR 2.88, 95% CI: 1.29-6.45), thrombocytopenia (OR 5.73, 95% CI: 1.91-17.14), and invasive mechanical ventilation (OR 10.54, 95% CI: 1.16-95.85) were independently associated with severity of PV-IVH.

CONCLUSIONS

Regardless of GA, electrolyte disorder, early-onset sepsis, thrombocytopenia, invasive mechanical ventilation, and male sex contributed to PV-IVH in preterm infants, and electrolyte disorder, thrombocytopenia, and invasive mechanical ventilation contributed to severe PV-IVH. These risk factors may combine to predict the incidence of PV-IVH in preterm infants.

Outcomes of very preterm infants with hyperglycaemia treated with insulin: A systematic review and meta-analysis

AIM

To study the outcomes of very preterm infants with hyperglycaemia treated with Insulin.

METHODS

This is a systematic review of randomised controlled trials (RCTs) and observational studies. PubMed, Medline, EMBASE, Cochrane Library, EMCARE and MedNar databases were searched in May 2022. Data were pooled separately for adjusted and unadjusted odds ratios (ORs) using random-effects model.

MAIN OUTCOME MEASURES

Mortality and morbidities (e.g. Necrotising enterocolitis [NEC], retinopathy of prematurity [ROP]) in very preterm (<32 weeks) or very low birth weight infants (<1500 g) after treatment of hyperglycaemia with insulin.

RESULTS

Sixteen studies with data from 5482 infants were included. Meta-analysis of unadjusted ORs from cohort studies showed that insulin treatment was significantly associated with increased mortality [OR 2.98 CI (1.03 to 8.58)], severe ROP [OR 2.23 CI (1.34 to 3.72)] and NEC [OR 2.19 CI (1.11 to 4)]. However, pooling of adjusted ORs did not show significant associations for any outcomes. The only included RCT found better weight gain in the insulin group, but no effect on mortality or morbidities. Certainty of evidence was 'Low' or 'Very low'.

CONCLUSION

Very low certainty evidence suggests that Insulin therapy may not improve outcomes of very preterm infants with hyperglycaemia.

Cerebral Effects of Neonatal Dysglycemia

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

Outcomes of very preterm infants with neonatal hyperglycaemia: a systematic review and meta-analysis

OBJECTIVE

To explore the association between hyperglycaemia and adverse outcomes in very preterm infants.

DESIGN

Systematic review and meta-analysis. Data were pooled separately for adjusted and unadjusted odds ratios (ORs) using random-effects model. Subgroup analysis was conducted based on study design (cohort and case control).

MAIN OUTCOME MEASURES

Association between hyperglycaemia in preterm neonates (<32 weeks or <1500 g) and mortality and morbidities.

FINDINGS

Forty-six studies (30 cohort and 16 case control) with data from 34 527 infants were included. Meta-analysis of unadjusted ORs from cohort studies found hyperglycaemia to be significantly associated with mortality, any-grade intraventricular haemorrhage (IVH), severe IVH, any-stage retinopathy of prematurity (ROP), severe ROP, sepsis, chronic lung disease and disability. However, pooling of adjusted ORs found significant associations only for mortality (adjusted OR (CI): 2.37 (1.40 to 4.01); I²: 36%; 6 studies), 'Any grade IVH' (adjusted OR (CI): 2.60 (1.09 to 6.20); I²: 0%; 2 studies) and 'Any stage ROP' (adjusted OR (CI): 3.70 (1.55 to 8.84); I²: 0%; 2 studies). Meta-regression analysis found glucose levels >10 mmol/L to be associated with increased odds of mortality compared with <10 mmol/L. Pooled analysis from case-control studies were similar to cohort studies for most outcomes but limited by small sample size. Longer duration of hyperglycaemia was associated with adverse outcomes. GRADE of evidence was 'Low' or 'Very low'.

CONCLUSION

Hyperglycaemia in very preterm infants is associated with higher odds of mortality, any-grade IVH and any-stage ROP. A limitation was lack of availability of adjusted ORs from many of the included studies.

PROSPERO REGISTRATION NUMBER

CRD42020193016.

Impact of glucose metabolism on the developing brain

Glucose is the most important substrate for proper brain functioning and development, with an increased glucose consumption in relation to the need of creating new brain structures and connections. Therefore, alterations in glucose homeostasis will inevitably be associated with changes in the development of the Nervous System. Several studies demonstrated how the alteration of glucose homeostasis - both hyper and hypoglycemia- may interfere with the development of brain structures and cognitivity, including deficits in intelligence quotient, anomalies in learning and memory, as well as differences in the executive functions. Importantly, differences in brain structure and functionality were found after a single episode of diabetic ketoacidosis suggesting the importance of glycemic control and stressing the need of screening programs for type 1 diabetes to protect children from this dramatic condition. The exciting progresses of the neuroimaging techniques such as diffusion tensor imaging, has helped to improve the understanding of the effects, outcomes and mechanisms underlying brain changes following dysglycemia, and will lead to more insights on the physio-pathological mechanisms and related neurological consequences about hyper and hypoglycemia.

Development and validation of a novel scoring system to predict severe intraventricular hemorrhage in very low birth weight infants

OBJECTIVE

We sought to develop and validate a novel scoring system for the prediction of severe intraventricular hemorrhage (SIVH) in very low birth weight infants (VLBWI).

METHODS

This retrospective cohort multicenter study included 615 VLBWI born between 24 and 32 weeks gestational age (GA). Multivariable logistic regression analyses were used to determine which factors evaluated within the first 5 days of life were associated with SIVH and the weights of these variables. The accuracy of the predictive scoring system was prospectively tested in the same units.

RESULTS

The final SIVH scoring system included the following variables: antenatal steroid therapy, GA, birth weight (BW), 1-min Apgar score, mechanical ventilation and hypotension. The SIVH scores used to divide the subjects into three tiers (low-risk (<5), moderate-risk (5-8) and high-risk (>8)) were developed based on these variables. Of infants with a score below 5, 1.2% (4/339) developed SIVH. Of those with a score above 8, 42.5% (17/40) developed SIVH. The scores were successfully verified in 99 VLBWI.

CONCLUSIONS

These findings suggest that among infants with a score >8, the incidence of SIVH is significantly higher. This scoring system can be used to predict the incidence of SIVH during the first 5 days after birth and may contribute to the early intervention in and prevention of SIVH.

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

OBJECTIVES

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

STUDY DESIGN

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

RESULTS

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

CONCLUSIONS

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

Preterm brain injury: Germinal matrix-intraventricular hemorrhage and post-hemorrhagic ventricular dilatation

Germinal matrix hemorrhage and intraventricular hemorrhages (GMH-IVH) remain a common and clinically significant problem in preterm infants, particularly extremely preterm infants. A large GMH-IVH is often complicated by posthemorrhagic ventricular dilation (PHVD) or parenchymal hemorrhagic infarction and is associated with an increased risk of adverse neurologic sequelae. The widespread use of cranial ultrasonography since the early 1980s has shown a gradual decrease in the incidence of GMH-IVH and has helped with the identification of antenatal and perinatal risk factors and timing of the lesion. The increased use of magnetic resonance imaging (MRI) has contributed to more detailed visualization of the site and extent of the GMH-IVH. In addition, MRI has contributed to the awareness of associated white matter changes as well as associated cerebellar hemorrhages. Although GMH-IVH and PHVD still cannot be prevented, cerebrospinal fluid drainage initiated in the early stage of PHVD development seems to be associated with a better neurodevelopmental outcome. Further studies are underway to improve treatment strategies for PHVD and to potentially prevent and repair GMH-IVH and PHVD and associated brain injury. This chapter discusses the pathogenesis, incidence, risk factors, and management, including preventive measures, of GHM-IVH and PHVD.

Chorioamnionitis Is a Risk Factor for Intraventricular Hemorrhage in Preterm Infants: A Systematic Review and Meta-Analysis

Although chorioamnionitis (CA) is a well-known risk factor for white matter disease of prematurity, the association with intraventricular hemorrhage (IVH) is controversial and has not been yet systematically reviewed. We performed a systematic review and meta-analysis of studies exploring the association between CA and IVH. A comprehensive literature search was conducted using PubMed/MEDLINE and EMBASE, from their inception to 1 July 2017. Studies were included if they examined preterm infants and reported primary data that could be used to measure the association between exposure to CA and the presence of IVH. A random-effects model was used to calculate odds ratios (OR) and 95% confidence intervals (CI). We found 1,284 potentially relevant studies, of which 85 met the inclusion criteria (46,244 infants, 13,432 CA cases). Meta-analysis showed that CA exposure was significantly associated with all grades IVH (OR 1.88, 95% CI 1.61-2.19), with grades 1-2 IVH (OR 1.69, 95% CI 1.22-2.34), and with grades 3-4 IVH (OR 1.62, 95% CI 1.42-1.85). Both clinical and histological CA were associated with an increased risk for developing IVH in very preterm infants. In contrast, the presence of funisitis did not increase IVH risk when compared to CA in the absence of funisitis (OR 1.22, 95% CI 0.89-1.67). Further meta-analyses confirmed earlier findings that CA-exposed infants have significantly lower gestational age (GA; mean difference [MD] -1.20 weeks) and lower birth weight (BW; MD -55 g) than the infants not exposed to CA. However, meta-regression and subgroup analysis could not demonstrate an association between the lower GA and BW and the risk of IVH in the CA-exposed infants. In conclusion, our data show that CA is a risk factor for IVH, but also a risk factor for greater prematurity and more clinical instability. In contrast to other complications of prematurity, such as patent ductus arteriosus, retinopathy of prematurity, or bronchopulmonary dysplasia, the effect of CA on IVH appears to be independent of CA as causative factor for very preterm birth.

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.