Hypoglycaemia and hyperglycaemia are associated with unfavourable outcome in infants with hypoxic ischaemic encephalopathy: a post hoc analysis of the CoolCap Study

Glucose instability and outcomes of neonates with hypoxic ischemic encephalopathy undergoing therapeutic hypothermia

BACKGROUND

To investigate the prevalence and associated outcomes of glucose abnormalities in infants with hypoxic ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH).

METHODS

Glucose values were reviewed in all HIE infants. Pearson's correlation was used to assess the association of hypo- and hyperglycemic episodes with neonatal brain MRI and neurodevelopmental outcomes (NDO) at 12 & 24 months.

RESULTS

Of 153 infants included, 31, 56 and 43 had episodes of hypo-, hyperglycemia and combined, respectively. Hyperglycemia and combined hypo/hyper had higher mortality (p = 0.035), seizures (p = 0.009), and longer hospitalization (p = 0.023). Hypo- and hyperglycemia were associated with parenchymal hemorrhages (p = 0.028 & p = 0.027, respectively). Hypoglycemia was associated with restricted diffusion (p = 0.014), while hyperglycemia was associated with cortical injuries (p = 0.045). Each hour of hyper- or hypoglycemia was associated with 5.2-5.8 times unfavorable outcomes (p < 0.001).

CONCLUSION

Blood glucose aberrations were detrimental in HIE infants treated with TH. Optimizing glucose management is crucial in this setting.

Blood glucose and β-hydroxybutyrate predict significant brain injury after hypoxia-ischemia in neonatal mice

BACKGROUND

The Vannucci procedure is widely used to model cerebral hypoxic-ischemic (HI) injury in neonatal rodents. Identifying minimally invasive biomarkers linked to brain injury would improve stratification of pups to experimental treatments. We hypothesized that extreme blood glucose (BG) and β-hydroxybutyrate (bHB) levels immediately after HI will correlate with severity of brain injury in this model.

METHODS

C57BL6 mice of both sexes underwent the Vannucci procedure with BG and bHB measured immediately after hypoxia. GFAP and α-fodrin were measured to assess injury severity at 4h, P11, P18 and P40. Open field (OF), Y-maze (YM), and Object-location task (OLT) were tested at P40.

RESULTS

Clinical seizures-like stereotypies during hypoxia were associated with lower post-hypoxia BG in HI-injured mice. Low BG after HI was related to higher GFAP expression, higher α-fodrin breakdown, lower residual regional volume, and worse working memory. BG was superior to bHB in ROC analysis with BG threshold of <111 mg/dL providing 100% specificity with 72% sensitivity for hippocampal HI-injury.

CONCLUSIONS

Post-hypoxic BG is a minimally invasive screening tool to identify pups with significant HI brain injury in the Vannucci model modified for mice improving our ability to stratify pups to experimental treatments to assess effectiveness.

IMPACT

End hypoxic-ischemic blood glucose levels are a reliable and inexpensive biomarker to detect hypoxic-ischemic brain injury in mice. Screening with blood glucose levels post-hypoxia allows appropriate stratification of those mouse pups most likely to be injured to experimental treatments improving validity and translatability of the results. These findings provide biological plausibility to the clinical observation that extreme blood glucose levels relate to worse outcomes after hypoxia-ischemia.

Effect of gestational age on cerebral lesions in neonatal encephalopathy

OBJECTIVE

To determine the risk on brain lesions according to gestational age (GA) in neonates with neonatal encephalopathy.

DESIGN

Secondary analysis of the prospective national French population-based cohort, Long-Term Outcome of NeonataL EncePhALopathy.

SETTING

French neonatal intensive care units.

PATIENTS

Neonates with moderate or severe neonatal encephalopathy (NE) born at ≥34 weeks' GA (wGA) between September 2015 and March 2017.

MAIN OUTCOME MEASURES

The results of MRI performed within the first 12 days were classified in seven injured brain regions: basal ganglia and thalami, white matter (WM), cortex, posterior limb internal capsule, corpus callosum, brainstem and cerebellum. A given infant could have several brain structures affected. Risk of brain lesion according to GA was estimated by crude and adjusted ORs (aOR).

RESULTS

MRI was available for 626 (78.8%) of the 794 included infants with NE. WM lesions predominated in preterm compared with term infants. Compared with 39-40 wGA neonates, those born at 34-35 wGA and 37-38 wGA had greater risk of WM lesions after adjusting for perinatal factors (aOR 4.0, 95% CI (1.5 to 10.7) and ORa 2.0, 95% CI (1.1 to 3.5), respectively).

CONCLUSION

WM is the main brain structure affected in late-preterm and early-term infants with NE, with fewer WM lesions as GA increases. This finding could help clinicians to estimate prognosis and improve the understanding of the pathophysiology of NE.

TRIAL REGISTRATION NUMBER

NCT02676063, ClinicalTrials.gov.

Neonatal dysglycemia: a review of dysglycemia in relation to brain health and neurodevelopmental outcomes

Neonatal dysglycemia has been a longstanding interest of research in neonatology. Adverse outcomes from hypoglycemia were recognized early but are still being characterized. Premature infants additionally introduced and led the reflection on the importance of neonatal hyperglycemia. Cohorts of infants following neonatal encephalopathy provided further information about the impacts of hypoglycemia and, more recently, highlighted hyperglycemia as a central concern for this population. Innovative studies exposed the challenges of management of neonatal glycemic levels with a "u-shape" relationship between dysglycemia and adverse neurological outcomes. Lately, glycemic lability has been recognized as a key factor in adverse neurodevelopmental outcomes. Research and new technologies, such as MRI and continuous glucose monitoring, offered novel insight into neonatal dysglycemia. Combining clinical, physiological, and epidemiological data allowed the foundation of safe operational definitions, including initiation of treatment, to delineate neonatal hypoglycemia as ≤47 mg/dL, and >150-180 mg/dL for neonatal hyperglycemia. However, questions remain about the appropriate management of neonatal dysglycemia to optimize neurodevelopmental outcomes. Research collaborations and clinical trials with long-term follow-up and advanced use of evolving technologies will be necessary to continue to progress the fascinating world of neonatal dysglycemia and neurodevelopment outcomes. IMPACT STATEMENT: Safe operational definitions guide the initiation of treatment of neonatal hypoglycemia and hyperglycemia. Innovative studies exposed the challenges of neonatal glycemia management with a "u-shaped" relationship between dysglycemia and adverse neurological outcomes. The importance of glycemic lability is also being recognized. However, questions remain about the optimal management of neonatal dysglycemia to optimize neurodevelopmental outcomes. Research collaborations and clinical trials with long-term follow-up and advanced use of evolving technologies will be necessary to progress the fascinating world of neonatal dysglycemia and neurodevelopment outcomes.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

SIGNIFICANCE

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

Exposure to Maternal Diabetes during Pregnancy Is Associated with Aggravated Short-Term Neonatal and Neurological Outcomes following Perinatal Hypoxic-Ischemic Encephalopathy

OBJECTIVE

Infants of diabetic mothers (IDM) are at higher risk of perinatal morbidities and glycemic instability, but the impact of maternal diabetes on neonatal and neurological short-term outcomes of neonates with hypoxic-ischemic encephalopathy (HIE) remains poorly described. Our objective was to determine the impact of maternal diabetes on neonatal and neurological short-term outcomes following neonatal HIE.

STUDY DESIGN

This was a retrospective single-center study including 102 term neonates with HIE who received therapeutic hypothermia (TH) treatment between 2013 and 2020. Multiple regression analysis was used to assess the relationship between the presence of maternal diabetes and short-term outcomes.

RESULTS

Neonates with HIE and maternal diabetes exposure had a significantly lower gestational age at birth (38.6 vs. 39.7 weeks of gestation, p = 0.005) and a significantly higher mean birth weight (3,588 ± 752 vs. 3,214 ± 514 g, p = 0.012). IDM with HIE were ventilated for longer duration (8 vs. 4 days, p = 0.0047) and had a longer neonatal intensive care unit (NICU) stay (18 vs. 11 days, p = 0.0483) as well as took longer time to reach full oral feed (15 vs. 7 days, p = 0.0432) compared with neonates of nondiabetic mother. Maternal diabetes was also associated with an increased risk of death or abnormal neurological examination at discharge in neonates with HIE (odds ratio: 6.41 [1.54-26.32]).

CONCLUSION

In neonates with HIE, maternal diabetes is associated with an increased risk of death or short-term neonatal morbidities, such as longer duration of ventilation, prolonged neonatal stay, greater need for tube feeding, and being discharged with an abnormal neurological examination. Strategies to prevent, reduce, or better control maternal diabetes during pregnancy should be prioritized to minimize complications after perinatal asphyxia.

KEY POINTS

· Maternal DB is associated with unfavorable outcomes.. · IDM have longer ventilatory support and tube feeding.. · IDM have higher risk of abnormal neurological examination..

Quality improvement and outcomes for neonates with hypoxic-ischemic encephalopathy: obstetrics and neonatal perspectives

Despite significant improvement in perinatal care and research, hypoxic ischemic encephalopathy (HIE) remains a global healthcare challenge. From both published research and reports of QI initiatives, we have identified a number of distinct opportunities that can serve as targets of quality improvement (QI) initiatives focused on reducing HIE. Specifically, (i) implementation of perinatal interventions to anticipate and timely manage high-risk deliveries; (ii) enhancement of team training and communication; (iii) optimization of early HIE diagnosis and management in referring centers and during transport; (iv) standardization of the approach when managing neonates with HIE during therapeutic hypothermia; (v) and establishment of protocols for family integration and follow-up, have been identified as important in successful QI initiatives. We also provide a framework and examples of tools that can be used to support QI work and discuss some of the perceived challenges and future opportunities for QI targeting HIE.

Incidence of encephalopathy and comorbidity in infants with perinatal asphyxia: a comparative prospective cohort study

Background

Programs that aim to improve the detection hypoxic-ischemic encephalopathy (HIE) should establish which neonates suffering from perinatal asphyxia need to be monitored within the first 6 h of life.

Method

An observational prospective cohort study of infants with gestational age ≥35 weeks, and above 1,800g, were included according to their arterial cord pH value (ApH): ≤7.00 vs. 7.01-7.10. Data was collected including obstetrical history, as well as neonatal comorbidities, including the presence of HIE, that happened within 6 h of life. A standardized neurological exam was performed at discharge.

Results

There were 9,537 births; 176 infants with ApH 7.01-7.10 and 117 infants with ApH ≤7.00. All 9 cases with moderate-to-severe HIE occurred among infants with ApH ≤7.00. The incidence of global and moderate-severe HIE was 3/1,000 and 1/1,000 births, respectively. Outcome at discharge (abnormal exam or death) showed an OR 12.03 (95% CI 1.53, 94.96) in infants with ApH ≤7.00 compared to ApH 7.01-7.10 cohort. Ventilation support was 5.1 times (95% CI 2.87, 9.03) more likely to be needed by those with cord ApH ≤7.00 compared to those with ApH 7.01-7.10, as well as hypoglycemia (37% vs. 25%; p = 0.026). In 55%, hypoglycemia occurred despite oral and/or intravenous glucose administration had been already initiated.

Conclusions

Cord pH 7.00 might be a safe pH cut-off point when developing protocols to monitor infants born with acidemia in order to identify infants with moderate or severe HIE early on. There is non-negligible comorbidity in the ApH ≤7.00 cohort, but also in the 7.01-7.10 cohort.

Metabolite Biomarkers for Early Ischemic-Hypoxic Encephalopathy: An Experimental Study Using the NeoBase 2 MSMS Kit in a Rat Model

Hypoxic-ischemic encephalopathy (HIE) is one of the most common causes of childhood disability. Hypothermic therapy is currently the only approved neuroprotective approach. However, early diagnosis of HIE can be challenging, especially in the first hours after birth when the decision to use hypothermic therapy is critical. Distinguishing HIE from other neonatal conditions, such as sepsis, becomes a significant problem in diagnosis. This study explored the utility of a metabolomic-based approach employing the NeoBase 2 MSMS kit to diagnose HIE using dry blood stains in a Rice-Vannucci model of HIE in rats. We evaluated the diagnostic fidelity of this approach in a range between 3 and 6 h after the onset of HIE, including in the context of systemic inflammation and concomitant hypothermic therapy. Discriminant analysis revealed several metabolite patterns associated with HIE. A logistic regression model using glycine levels achieved high diagnostic fidelity with areas under the receiver operating characteristic curve of 0.94 at 3 h and 0.96 at 6 h after the onset of HIE. In addition, orthogonal partial least squares discriminant analysis, which included five metabolites, achieved 100% sensitivity and 80% specificity within 3 h of HIE. These results highlight the significant potential of the NeoBase 2 MSMS kit for the early diagnosis of HIE and could improve patient management and outcomes in this serious illness.

Motor, cognitive and behavioural outcomes after neonatal hypoxic-ischaemic encephalopathy

INTRODUCTION

The current neurodevelopmental status of patients with neonatal hypoxic-ischaemic encephalopathy (HIE) in Spain is unknown. Recent European studies highlight a shift of severe pathology towards mild motor disorders and emotional problems. The aim of this study was to analyse neurodevelopmental outcomes in a cohort of neonates with HIE at age 3 years.

PATIENTS AND METHOD

Multicentre observational study of neonates born at 35 or more weeks of gestation with moderate to severe HIE in 2011-2013 in 12 hospitals in a large Spanish region (91 217 m2), with the recruitment extended through 2017 in the coordinating hospital. We analysed the findings of neonatal neuroimaging and neurodevelopmental test scores at 3 years (Bayley-III, Peabody Picture Vocabulary Test and Child Behavior Checklist). The sample included 79 controls with no history of perinatal asphyxia.

RESULTS

Sixty-three patients were recruited, of whom 5 (7.9%) were excluded due to other pathology and 14 (24%) died. Of the 44 survivors, 42 (95.5%) were evaluated. Of these 42, 10 (24%) had adverse outcomes (visual or hearing impairment, epilepsy, cerebral palsy or developmental delay). Other detected problems were minor neurological signs in 6 of the 42 (14%) and a higher incidence of emotional problems compared to controls: introversion (10.5% vs. 1.3%), anxiety (34.2% vs. 11.7%) and depression (28.9% vs. 7.8%) (P < .05). The severity of the lesions on neuroimaging was significantly higher in patients with motor impairment (P = .004) or who died or had an adverse outcome (P = .027).

CONCLUSION

In addition to classical sequelae, the followup of patients with neonatal HIE should include the diagnosis and treatment of minor motor disorders and social and emotional problems.

Neonatal Hypoxic-Ischemic Encephalopathy and Hypothermia Treatment

Neonatal hypoxic-ischemic encephalopathy (HIE) is an important clinical entity because it is associated with death and long-term disability, including cognitive impairment, cerebral palsy, seizures, and neurosensory deficits. Over the past 40 years, there has been an intensive search to identify therapies to improve the prognosis of neonates with HIE. Hypothermia treatment represents the culmination of laboratory investigations including small and large animal studies, followed by pilot human studies, and, finally, randomized controlled trials to establish efficacy and safety. Clinical trials have demonstrated that hypothermia treatment reduces mortality and improves early childhood outcome among survivors. Hypoxic-ischemic encephalopathy is a multi-system disease process that requires intensive medical support for brain monitoring and monitoring of non-central nervous system organ dysfunction. Treatment must be conducted in a level III or IV neonatal intensive care unit with infrastructure for an integrated approach to care for critically ill neonates. Hypothermia treatment is the first and currently the only therapy to improve outcomes for neonates with HIE and indicates that HIE is modifiable. However, outcomes likely can be improved further. Hypothermia treatment has accelerated investigation of other therapies to combine with hypothermia. It has also stimulated a more intensive approach to brain monitoring, which allows earlier intervention for complications. Finally, HIE and hypothermia treatment negatively influences the psychological state of affected families, and there is growing recognition of the importance of trauma-informed principles to guide medical professionals.

Hypoglycaemia and hyperglycaemia in neonatal encephalopathy: a systematic review and meta-analysis

IMPORTANCE

Although hypoglycaemia and hyperglycaemia represent the most common metabolic problem in neonates, there is still uncertainty regarding the effects of glucose homoeostasis on the neurological outcomes of infants with neonatal encephalopathy (NE).

OBJECTIVE

To systematically investigate the association between neonatal hypoglycaemia and hyperglycaemia with adverse outcome in children who suffered from NE.

STUDY SELECTION

We searched Pubmed, Embase and Web of Science databases to identify studies which reported prespecified outcomes and compared infants with NE who had been exposed to neonatal hypoglycaemia or hyperglycaemia with infants not exposed.

DATA ANALYSIS

We assessed the risk of bias (ROBINS-I), quality of evidence (Grading of Recommendations, Assessment, Development and Evaluation (GRADE)) for each of the studies. RevMan was used for meta-analysis (inverse variance, fixed effects).

MAIN OUTCOME

Death or neurodevelopmental outcomes at 18 months of age or later.

RESULTS

82 studies were screened, 28 reviewed in full and 12 included. Children who were exposed to neonatal hypoglycaemia had higher odds of neurodevelopmental impairment or death (6 studies, 685 infants; 40.6% vs 25.4%; OR=2.17, 95% CI 1.46 to 3.25; p=0.0001). Neonatal exposure to hyperglycaemia was associated with death or neurodisability at 18 months or later (7 studies, 807 infants; 46.1% vs 28.0%; OR=3.07, 95% CI 2.17 to 4.35; p<0.00001). These findings were confirmed in the subgroup analysis, which included only the infants who underwent therapeutic hypothermia.

CONCLUSIONS

These data suggest that neonatal hypoglycaemia and hyperglycaemia may be associated with the neurodevelopmental outcome later on in infants with NE. Further studies with long-term follow-up are needed to optimise the metabolic management of these high-risk infants.

PROSPERO REGISTRATION NUMBER

CRD42022368870.

Association between continuous glucose profile during therapeutic hypothermia and unfavorable outcome in neonates with hypoxic-ischemic encephalopathy209 23-32

BACKGROUND

The detection and management of blood glucose abnormalities in high-risk neonates are crucial for clinical care. The objective of the study was to investigate the continuous glucose profile of hypoxic-ischemic encephalopathy (HIE) patients in the whole-process of therapeutic hypothermia (TH) and its association with clinical and neurological outcomes.

METHOD

In this single-center retrospective study, HIE patients who received both TH and continuous glucose monitoring (CGM) were recruited from March 2016 to September 2021.

RESULTS

Of 47 neonates recruited, 24 had unfavorable outcome. Dysglycemia was most prevalent in the first 24 h of TH, among which hyperglycemia occurred more frequently. CGM showed that the duration, episodes and area under curve (AUC) of hypoglycemia were statistically different in neonates with different outcomes. The occurrence, longer duration, greater AUC of hypoglycemia and an early high coefficient of variation (CV%, CV = SD/mean) were associated with unfavorable outcomes (aOR 26.55 [2.02-348.5], aOR 2.11 [1.08-4.14], aOR 1.80 [1.11-2.91] and aOR respectively), while hyperglycemia was not.

CONCLUSION

During the whole process of TH, hypoglycemia and early unstable glycemic variability were strongly associated with unfavorable outcomes. CGM can instantly detect dysglycemia and facilitate precise glucose management in HIE neonates.

Perinatal asphyxia and hypothermic treatment from the endocrine perspective

Introduction

Perinatal asphyxia is one of the three most important causes of neonatal mortality and morbidity. Therapeutic hypothermia represents the standard treatment for infants with moderate-severe perinatal asphyxia, resulting in reduction in the mortality and major neurodevelopmental disability. So far, data in the literature focusing on the endocrine aspects of both asphyxia and hypothermia treatment at birth are scanty, and many aspects are still debated. Aim of this narrative review is to summarize the current knowledge regarding the short- and long-term effects of perinatal asphyxia and of hypothermia treatment on the endocrine system, thus providing suggestions for improving the management of asphyxiated children.

Results

Involvement of the endocrine system (especially glucose and electrolyte disturbances, adrenal hemorrhage, non-thyroidal illness syndrome) can occur in a variable percentage of subjects with perinatal asphyxia, potentially affecting mortality as well as neurological outcome. Hypothermia may also affect endocrine homeostasis, leading to a decreased incidence of hypocalcemia and an increased risk of dilutional hyponatremia and hypercalcemia.

Conclusions

Metabolic abnormalities in the context of perinatal asphyxia are important modifiable factors that may be associated with a worse outcome. Therefore, clinicians should be aware of the possible occurrence of endocrine complication, in order to establish appropriate screening protocols and allow timely treatment.

Cerebral Glucose Concentration in Neonatal Hypoxic-Ischemic Encephalopathy during Therapeutic Hypothermia

OBJECTIVE

To determine cerebral glucose concentration and its relationship with glucose infusion rate (GIR) and blood glucose concentration in neonatal encephalopathy during therapeutic hypothermia (TH).

METHODS

This was an observational study in which cerebral glucose during TH was quantified by magnetic resonance (MR) spectroscopy and compared with mean blood glucose at the time of scan. Clinical data (gestational age, birth weight, GIR, sedative use) that could affect glucose use were collected. The severity and pattern of brain injury on MR imaging were scored by a neuroradiologist. Student t test, Pearson correlation, repeated measures ANOVA, and multiple regression analysis were performed.

RESULTS

Three-hundred-sixty blood glucose values and 402 MR spectra from 54 infants (30 female infants; mean gestational age 38.6 ± 1.9 weeks) were analyzed. In total, 41 infants had normal-mild and 13 had moderate-severe injury. Median GIR and blood glucose during TH were 6.0 mg/kg/min (IQR 5-7) and 90 mg/dL (IQR 80-102), respectively. GIR did not correlate with blood or cerebral glucose. Cerebral glucose was significantly greater during than after TH (65.9 ± 22.9 vs 60.0 ± 25.2 mg/dL, P < .01), and there was a significant correlation between blood glucose and cerebral glucose during TH (basal ganglia: r = 0.42, thalamus: r = 0.42, cortical gray matter: r = 0.39, white matter: r = 0.39, all P < .01). There was no significant difference in cerebral glucose concentration in relation to injury severity or pattern.

CONCLUSIONS

During TH, cerebral glucose concentration is partly dependent on blood glucose concentration. Further studies to understand brain glucose use and optimal glucose concentrations during hypothermic neuroprotection are needed.

Early Glycemic State and Outcomes of Neonates With Hypoxic-Ischemic Encephalopathy

OBJECTIVES

In infants with hypoxic-ischemic encephalopathy (HIE), conflicting information on the association between early glucose homeostasis and outcome exists. We characterized glycemic profiles in the first 12 hours after birth and their association with death and neurodevelopmental impairment (NDI) in neonates with moderate or severe HIE undergoing therapeutic hypothermia.

METHODS

This post hoc analysis of the High-dose Erythropoietin for Asphyxia and Encephalopathy trial included n = 491 neonates who had blood glucose (BG) values recorded within 12 hours of birth. Newborns were categorized based on their most extreme BG value. BG >200 mg/dL was defined as hyperglycemia, BG <50 mg/dL as hypoglycemia, and 50 to 200 mg/dL as euglycemia. Primary outcome was defined as death or any NDI at 22 to 36 months. We calculated odds ratios for death or NDI adjusted for factors influencing glycemic state (aOR).

RESULTS

Euglycemia was more common in neonates with moderate compared with severe HIE (63.6% vs 36.6%; P < .001). Although hypoglycemia occurred at similar rates in severe and moderate HIE (21.4% vs 19.5%; P = .67), hyperglycemia was more common in severe HIE (42.3% vs 16.9%; P < .001). Compared with euglycemic neonates, both, hypo- and hyperglycemic neonates had an increased aOR (95% confidence interval) for death or NDI (2.62; 1.47-4.67 and 1.77; 1.03-3.03) compared to those with euglycemia. Hypoglycemic neonates had an increased aOR for both death (2.85; 1.09-7.43) and NDI (2.50; 1.09-7.43), whereas hyperglycemic neonates had increased aOR of 2.52 (1.10-5.77) for death, but not NDI.

CONCLUSIONS

Glycemic profile differs between neonates with moderate and severe HIE, and initial glycemic state is associated death or NDI at 22 to 36 months.

Effect of birth asphyxia on neonatal blood glucose during the early postnatal life: A multi-center study in Hubei Province, China

BACKGROUND

Birth asphyxia causes hypoxia or inadequate perfusion to the organs of newborns, leading to metabolism dysfunctions including blood glucose disorders.

METHODS

Neonates with and without birth asphyxia were retrospectively recruited from 53 hospitals in Hubei Province from January 1 to December 31, 2018. In summary, 875, 1139, and 180 cases in the control group, the mild asphyxia group, and the severe asphyxia group were recruited, respectively. Neonatal blood glucose values at postnatal 1, 2, 6, and 12 h (time error within 0.5 h was allowed) were gathered from the medical records.

RESULTS

The incidence rates of hyperglycemia in the control group, the mild asphyxia group and the severe asphyxia group were 2.97%, 7.90%, and 23.33%, respectively (p < 0.001). Additionally, the incidence rates of hypoglycemia in the three groups above were 3.66%, 4.13%, and 7.78%, respectively (p = 0.042). The blood glucose values of neonates with hypoglycemia in the asphyxia group were lower than in the control group (p = 0.003). Furthermore, the blood glucose values of neonates with hyperglycemia were highest in the severe asphyxia group (p < 0.001). There were 778 and 117 cases with blood glucose records at four predefined time points in the mild and severe asphyxia group, respectively. The incidence of blood glucose disorders in the mild asphyxia group significantly decreased from postnatal 6 h (p＜0.05). However, we found no obvious changes of the incidence of glucose disorders within postnatal 12 h in the severe asphyxia group (p = 0.589).

CONCLUSION

Birth asphyxia is likely to cause neonatal blood glucose disorders, both hypoglycemia and hyperglycemia, during the early postnatal life. The neonates with severe asphyxia have higher incidence, worse severity and longer duration of blood glucose disorders than neonates with mild asphyxia.

Severity and duration of dysglycemia and brain injury among patients with neonatal encephalopathy

Background

Evidence is needed to inform thresholds for glycemic management in neonatal encephalopathy (NE). We investigated how severity and duration of dysglycemia relate to brain injury after NE.

Methods

A prospective cohort of 108 neonates ≥36 weeks gestational age with NE were enrolled between August 2014 and November 2019 at the Hospital for Sick Children, in Toronto, Canada. Participants underwent continuous glucose monitoring for 72 h, MRI at day 4 of life, and follow-up at 18 months. Receiver operating characteristic curves were used to assess the predictive value of glucose measures (minimum and maximum glucose, sequential 1 mmol/L glucose thresholds) during the first 72 h of life (HOL) for each brain injury pattern (basal ganglia, watershed, focal infarct, posterior-predominant). Linear and logistic regression analyses were used to assess the relationship between abnormal glycemia and 18-month outcomes (Bayley-III composite scores, Child Behavior Checklist [CBCL] T-scores, neuromotor score, cerebral palsy [CP], death), adjusting for brain injury severity.

Findings

Of 108 neonates enrolled, 102 (94%) had an MRI. Maximum glucose during the first 48 HOL best predicted basal ganglia (AUC = 0.811) and watershed (AUC = 0.858) injury. Minimum glucose was not predictive of brain injury (AUC <0.509). Ninety-one (89%) infants underwent follow-up assessments at 19.0 ± 1.7 months. A glucose threshold of >10.1 mmol/L during the first 48 HOL was associated with 5.8-point higher CBCL Internalizing Composite T-score (P = 0.029), 0.3-point worse neuromotor score (P = 0.035), 8.6-fold higher odds for CP diagnosis (P = 0.014). While the glucose threshold of >10.1 mmol/L during the first 48 HOL was associated with higher odds of the composite outcome of severe disability or death (OR 3.0, 95% CI 1.0-8.4, P = 0.042), it was not associated with the composite outcome of moderate-to-severe disability or death (OR 0.9, 95% CI 0.4-2.2, P = 0.801). All associations with outcome lost significance after adjusting for brain injury severity.

Interpretation

Maximum glucose concentration in the first 48 HOL is predictive of brain injury after NE. Further trials are needed to assess if protocols to control maximum glucose concentrations improve outcomes after NE.

Funding

Canadian Institutes for Health Research, National Institutes of Health, and SickKids Foundation.

Brain-Oriented Strategies for Neuroprotection of Asphyxiated Newborns in the First Hours of Life

Perinatal asphyxia represents the first cause of severe neurological disabilities and the second cause of neonatal death in term-born babies. Currently, no treatment can prevent immediate cell death from necrosis, but some therapeutic interventions, such as therapeutic hypothermia (TH), can reduce delayed cell death from apoptosis. TH significantly improves the combined outcome of mortality or major neurodevelopmental disability, but the number of patients to be treated is 7 to get 1 child with no adverse neurological outcome. The aim of this educational review is to analyze the other care strategies to be implemented to improve the neurological outcome of children with hypoxic ischemic encephalopathy (HIE). Hypocapnia, hypoglycemia, pain control, and functional brain monitoring are recognized as appropriate approaches to improve outcome in critically ill infants with HIE. Pharmacologic neuroprotective adjuncts are currently under investigation. New drugs such as allopurinol and melatonin seem to provide positive effects although more randomized controlled trials are required to establish the effective therapeutic scheme. In the meantime, sustaining the respiratory, metabolic, and cardiovascular system during TH can be a valuable aid in managing and treating the patient with HIE in an optimal way.

Glycemia and Neonatal Encephalopathy: Outcomes in the LyTONEPAL (Long-Term Outcome of Neonatal Hypoxic EncePhALopathy in the Era of Neuroprotective Treatment With Hypothermia) Cohort

OBJECTIVES

To assess in newborns with neonatal encephalopathy (NE), presumptively related to a peripartum hypoxic-ischemic event, the frequency of dysglycemia and its association with neonatal adverse outcomes.

STUDY DESIGN

We conducted a secondary analysis of LyTONEPAL (Long-Term Outcome of Neonatal hypoxic EncePhALopathy in the era of neuroprotective treatment with hypothermia), a population-based cohort study including 545 patients with moderate-to-severe NE. Newborns were categorized by the glycemia values assessed by routine clinical care during the first 3 days of life: normoglycemic (all glycemia measurements ranged from 2.2 to 8.3 mmol/L), hyperglycemic (at least 1 measurement >8.3 mmol/L), hypoglycemic (at least 1 measurement <2.2 mmol/L), or with glycemic lability (measurements included at least 1 episode of hypoglycemia and 1 episode of hyperglycemia). The primary adverse outcome was a composite outcome defined by death and/or brain lesions on magnetic resonance imaging, regardless of severity or location.

RESULTS

In total, 199 newborns were categorized as normoglycemic (36.5%), 74 hypoglycemic (13.6%), 213 hyperglycemic (39.1%), and 59 (10.8%) with glycemic lability, based on the 2593 glycemia measurements collected. The primary adverse outcome was observed in 77 (45.8%) normoglycemic newborns, 37 (59.7%) with hypoglycemia, 137 (67.5%) with hyperglycemia, and 40 (70.2%) with glycemic lability (P < .01). With the normoglycemic group as the reference, the aORs and 95% 95% CIs for the adverse outcome were significantly greater for the group with hyperglycemia (aOR 1.81; 95% CI 1.06-3.11).

CONCLUSIONS

Dysglycemia affects nearly two-thirds of newborns with NE and is independently associated with a greater risk of mortality and/or brain lesions on magnetic resonance imaging.

TRIAL REGISTRATION

NCT02676063.

Plasma Biomarkers of Evolving Encephalopathy and Brain Injury in Neonates with Hypoxic-Ischemic Encephalopathy

OBJECTIVE

The objective of the study was to evaluate the relationship between a panel of candidate plasma biomarkers and (1) death or severe brain injury on magnetic resonance imaging (MRI) and (2) dysfunctional cerebral pressure autoregulation as a measure of evolving encephalopathy.

STUDY DESIGN

Neonates with moderate-to-severe hypoxic-ischemic encephalopathy (HIE) at 2 level IV neonatal intensive care units were enrolled into this observational study. Patients were treated with therapeutic hypothermia (TH) and monitored with continuous blood pressure monitoring and near-infrared spectroscopy. Cerebral pressure autoregulation was measured by the hemoglobin volume phase (HVP) index; a higher HVP index indicates poorer autoregulation. Serial blood samples were collected during TH and assayed for Tau, glial fibrillary acidic protein, and neurogranin. MRIs were assessed using National Institutes of Child Health and Human Development scores. The relationships between the candidate biomarkers and (1) death or severe brain injury on MRI (defined as a National Institutes of Child Health and Human Development score of ≥ 2B) and (2) autoregulation were evaluated using bivariate and adjusted logistic regression models.

RESULTS

Sixty-two patients were included. Elevated Tau levels on days 2-3 of TH were associated with death or severe injury on MRI (aOR: 1.06, 95% CI: 1.03-1.09; aOR: 1.04, 95% CI: 1.01-1.06, respectively). Higher Tau was also associated with poorer autoregulation (higher HVP index) on the same day (P = .022).

CONCLUSIONS

Elevated plasma levels of Tau are associated with death or severe brain injury by MRI and dysfunctional cerebral autoregulation in neonates with HIE. Larger-scale validation of Tau as a biomarker of brain injury in neonates with HIE is warranted.

Continuous glucose monitoring during therapeutic hypothermia for hypoxic ischaemic encephalopathy: a feasibility study

OBJECTIVES

Glucose dysregulation is common in infants with hypoxic ischaemic encephalopathy (HIE) and is likely to exacerbate cerebral injury. Infrequent measurement of glucose concentrations makes both identification and prevention of this risk challenging. Continuous glucose monitoring (CGM) has the potential to address both these challenges, but has not been explored in these infants. We aimed to evaluate the feasibility and potential impact of real-time CGM in term infants with HIE being treated with therapeutic hypothermia (TH).

DESIGN

Feasibility study.

SETTING

Tertiary-level neonatal unit, UK.

PATIENTS

Term infants with HIE undergoing TH.

INTERVENTION

A CGM sensor was inserted within 48 hours of birth and kept in situ for the first week of life. Clinical staff were blinded to the CGM recordings and clinical decisions were based on blood glucose assays.

MAIN OUTCOME MEASURES

(1) Accuracy of CGM values during and post TH, (2) Per cent of time spent outside the clinical range (2.6-10 mmol/L), (3) Episodes of hypoglycaemia and hyperglycaemia, (4) Adverse effects.

RESULTS

The accuracy of CGM values during TH were comparable to those when infants were normothermic. There was wide variation in per cent time outside the target range (2.6-10 mmol/L) between infants (median 5%, range 0%-34%). CGM identified 44% of infants with ≥1 episode of hypoglycaemia (<2.6 mmol/L) and 50% with ≥1 episode of hyperglycaemia (>10 mmol/L). No adverse events were observed.

CONCLUSIONS

This study demonstrates that CGM could be a useful adjunct for glucose monitoring in babies undergoing TH who are at risk of both hypoglycaemia and hyperglycaemia.

Neurologic Disorders of the Foal

Neurologic disease of foals is a diagnostic and therapeutic challenge for veterinarians. Disease conditions such as neonatal encephalopathy are seen as well as developmental and congenital defects, bacterial infections, and trauma. Neonatal encephalopathy can be considered a "syndrome" with a variety of causes resulting in a similar clinical presentation. These causes can be categorized as maladaptation, hypoxic/ischemic encephalopathy, and metabolic abnormalities, all leading to signs of cerebral and brainstem disease. Spinal cord signs may occasionally be seen, but these signs are usually overshadowed by cerebral disease. Treatment in most cases involves supportive care and outcome is favorable in most cases.

Recent advances in diagnostics of neonatal hypoxic ischemic encephalopathy

The prognosis in neonatal hypoxic ischemic encephalopathy (HIE) depends on early differential diagnosis for justified administration of emergency therapeutic hypothermia. The moment of therapy initiation directly affects the long-term neurological outcome: the earlier the commencement, the better the prognosis. This review analyzes recent advances in systems biology that facilitate early differential diagnosis of HIE as a pivotal complement to clinical indicators. We discuss the possibilities of clinical translation for proteomic, metabolomic and extracellular vesicle patterns characteristic of HIE and correlations with severity and prognosis. Identification and use of selective biomarkers of brain damage in neonates during the first hours of life is hindered by systemic effects of hypoxia. Chromatography– mass spectrometry blood tests allow analyzing hundreds and thousands of metabolites in a small biological sample to identify characteristic signatures of brain damage. Clinical use of advanced analytical techniques will facilitate the accurate and timely diagnosis of HIE for enhanced management.

Hypoglycemia in Infants with Hypoxic-Ischemic Encephalopathy Is Associated with Additional Brain Injury and Worse Neurodevelopmental Outcome

OBJECTIVE

To determine the incidence of hypoglycemia among infants with hypoxic-ischemic encephalopathy (HIE) who received therapeutic hypothermia, and to assess whether infants with hypoglycemia had more brain injury on magnetic resonance imaging (MRI) or differences in neurodevelopmental outcome.

STUDY DESIGN

Single-center, retrospective cohort study including infants cooled for HIE. Hypoglycemia (blood glucose <36.0 mg/dL <2 hours and <46.8 mg/dL ≥2 hours after birth) was analyzed in the period before brain MRI. Brain injury was graded using a validated score. Motor and neurocognitive outcomes were assessed at 2 years for all survivors, and 5.5 years for a subset who had reached this age.

RESULTS

Of 223 infants analyzed, 79 (35.4%) had hypoglycemia. MRI was performed in 187 infants. Infants with hypoglycemia (n = 65) had higher brain injury scores (P = .018). After adjustment for HIE severity, hypoglycemia remained associated with higher injury scores (3.6 points higher; 95% CI, 0.8-6.4). Hyperglycemia did not affect MRI scores. In survivors at 2 years (n = 154) and 5.5 years (n = 102), a univariable analysis showed lower 2-year motor scores and lower motor and cognitive scores at preschool age in infants with hypoglycemia. After adjustment for HIE severity, infants with hypoglycemia had 9 points lower IQs (P = .023) and higher odds of adverse outcomes at preschool age (3.6; 95% CI, 1.4-9.0).

CONCLUSIONS

More than one-third of infants cooled for HIE had hypoglycemia. These infants had a higher degree of brain injury on MRI and lower cognitive function at preschool age. Strategies to avoid hypoglycemia should be optimized in this setting.

Hypothermia is not therapeutic in a neonatal piglet model of inflammation-sensitized hypoxia-ischemia

BACKGROUND

Perinatal inflammation combined with hypoxia-ischemia (HI) exacerbates injury in the developing brain. Therapeutic hypothermia (HT) is standard care for neonatal encephalopathy; however, its benefit in inflammation-sensitized HI (IS-HI) is unknown.

METHODS

Twelve newborn piglets received a 2 µg/kg bolus and 1 µg/kg/h infusion over 52 h of Escherichia coli lipopolysaccharide (LPS). HI was induced 4 h after LPS bolus. After HI, piglets were randomized to HT (33.5 °C 1-25 h after HI, n = 6) or normothermia (NT, n = 6). Amplitude-integrated electroencephalogram (aEEG) was recorded and magnetic resonance spectroscopy (MRS) was acquired at 24 and 48 h. At 48 h, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)-positive brain cell death, microglial activation/proliferation, astrogliosis, and cleaved caspase-3 (CC3) were quantified. Hematology and plasma cytokines were serially measured.

RESULTS

Two HT piglets died. aEEG recovery, thalamic and white matter MRS lactate/N-acetylaspartate, and TUNEL-positive cell death were similar between groups. HT increased microglial activation in the caudate, but had no other effect on glial activation/proliferation. HT reduced CC3 overall. HT suppressed platelet count and attenuated leukocytosis. Cytokine profile was unchanged by HT.

CONCLUSIONS

We did not observe protection with HT in this piglet IS-HI model based on aEEG, MRS, and immunohistochemistry. Immunosuppressive effects of HT and countering neuroinflammation by LPS may contribute to the observed lack of HT efficacy. Other immunomodulatory strategies may be more effective in IS-HI.

IMPACT

Acute infection/inflammation is known to exacerbate perinatal brain injury and can worsen the outcomes in neonatal encephalopathy. Therapeutic HT is the current standard of care for all infants with NE, but the benefit in infants with coinfection/inflammation is unknown. In a piglet model of inflammation (LPS)-sensitized HI, we observed no evidence of neuroprotection with cooling for 24 h, based on our primary outcome measures: aEEG, MRS Lac/NAA, and histological brain cell death. Additional neuroprotective agents, with beneficial immunomodulatory effects, require exploration in IS-HI models.

The new European resuscitation council guidelines on newborn resuscitation and support of the transition of infants at birth: An educational article

In this educational article, we summarize the changes in the new European Resuscitation Council guidelines on Newborn Resuscitation and Support of the Transition of Infants at Birth, emphasizing important aspects for the pediatric anesthesiologist including umbilical cord management, airway management, inflation pressure, and oxygen in relation with gestational age and situation. Using a fictitious case to illustrate the main points, we give a summary of the changes and the evidence behind them.

Body temperature, heart rate and long-term outcome of cooled infants: an observational study

BACKGROUND

Therapeutic hypothermia is a standard of care for neonatal encephalopathy; however, approximately one in two newborn infants fails to respond to this treatment. Recent studies have suggested potential relationships between body temperature, heart rate and the outcome of cooled infants.

METHODS

The clinical data of 756 infants registered to the Baby Cooling Registry of Japan between January 2012 and December 2016 were analysed to assess the relationship between body temperature, heart rate and adverse outcomes (death or severe impairment at 18 months corrected age).

RESULTS

A lower body temperature at admission was associated with adverse outcomes in the univariate analysis (P < 0.001), the significance of which was lost when adjusted for the severity of encephalopathy and other covariates. A higher body temperature during cooling and higher heart rate before and during cooling were associated with adverse outcomes in both univariate (all P < 0.001) and multivariate (P = 0.012, P < 0.001 and P < 0.001, respectively) analyses.

CONCLUSIONS

Severe hypoxia-ischaemia might be a common causative of faster heart rates before and during cooling and low body temperature before cooling, whereas causal relationships between slightly higher temperatures during cooling and adverse outcomes need to be elucidated in future studies.

IMPACT

In a large cohort of encephalopathic newborn infants, dual roles of body temperature to the outcome were shown; adverse outcomes were associated with a lower body temperature at admission and higher body temperature during cooling. A higher heart rate before and during cooling were associated with adverse outcomes. Severe hypoxia-ischaemia might be a common causative of faster heart rates before and during cooling and low body temperature before cooling. The exact mechanism underlying the relationship between slightly higher body temperature during cooling and adverse outcomes remains unknown, which needs to be elucidated in future studies.

The Utility of Cerebral Autoregulation Indices in Detecting Severe Brain Injury Varies by Cooling Treatment Phase in Neonates with Hypoxic-Ischemic Encephalopathy

Identifying the hemodynamic range that best supports cerebral perfusion using near infrared spectroscopy (NIRS) autoregulation monitoring is a potential physiologic marker for neonatal hypoxic-ischemic encephalopathy (HIE) during therapeutic hypothermia. However, an optimal autoregulation monitoring algorithm has not been identified for neonatal clinical medicine. We tested whether the hemoglobin volume phase (HVP), hemoglobin volume (HVx), and pressure passivity index (PPI) identify changes in autoregulation that are associated with brain injury on MRI or death. The HVP measures the phase difference between a NIRS metric of cerebral blood volume, the total hemoglobin (THb), and mean arterial blood pressure (MAP) at the frequency of maximum coherence. The HVx is the correlation coefficient between MAP and THb. The PPI is the percentage of coherent MAP-DHb (difference between oxygenated and deoxygenated hemoglobin, a marker of cerebral blood flow) epochs in a chosen time period. Neonates cooled for HIE were prospectively enrolled in an observational study in two neonatal intensive care units. In analyses adjusted for study site and encephalopathy level, all indices detected relationships between poor autoregulation in the first 6 h after rewarming with a higher injury score on MRI. Only HVx and PPI during hypothermia and the PPI during rewarming identified autoregulatory dysfunction associated with a poor outcome independent of study site and encephalopathy level. Our findings suggest that the accuracy of mathematical autoregulation algorithms in detecting the risk of brain injury or death may depend on temperature and postnatal age. Extending autoregulation monitoring beyond the standard 72 h of therapeutic hypothermia may serve as a method to provide personalized care by assessing the need for and efficacy of future therapies after the hypothermia treatment phase.

Early Blood Glucose Level Post-Admission Correlates with the Outcomes and Oxidative Stress in Neonatal Hypoxic-Ischemic Encephalopathy

The antioxidant defense system is involved in the pathogenesis of neonatal hypoxic-ischemic encephalopathy (HIE). To analyze the relationship between first serum blood glucose levels and outcomes in neonatal HIE, seventy-four patients were divided, based on the first glucose level, into group 1 (>0 mg/dL and <60 mg/dL, n =11), group 2 (≥60 mg/dL and <150 mg/dL, n = 49), and group 3 (≥150 mg/dL, n = 14). Abnormal glucose levels had poor outcomes among three groups in terms of the clinical stage (p = 0.001), brain parenchymal lesion (p = 0.004), and neurodevelopmental outcomes (p = 0.029). Hearing impairment was more common in group 3 than in group 1 (p = 0.062) and group 2 (p = 0.010). The MRI findings of group 3 exhibited more thalamus and basal ganglion lesions than those of group 1 (p = 0.012). The glucose level was significantly correlated with clinical staging (p< 0.001), parenchymal brain lesions (p = 0.044), hearing impairment (p = 0.003), and neurodevelopmental outcomes (p = 0.005) by Pearson’s test. The first blood glucose level in neonatal HIE is an important biomarker for clinical staging, MRI findings, as well as hearing and neurodevelopment outcomes. Hyperglycemic patients had a higher odds ratio for thalamus, basal ganglia, and brain stem lesions than hypoglycemic patients with white matter and focal ischemic injury. Hyperglycemia can be due to prolonged or intermittent hypoxia and can be associated with poor outcomes.

Effect of glucose metabolism disorders on the short-term prognosis in neonates with asphyxia: a multicenter study in Hubei Province, China

OBJECTIVES

To study the effect of glucose metabolism disorders on the short-term prognosis in neonates with asphyxia.

METHODS

A retrospective analysis was performed on the medical data of the neonates with asphyxia who were admitted to 52 hospitals in Hubei Province of China from January to December, 2018 and had blood glucose data within 12 hours after birth. Their blood glucose data at 1, 2, 6, and 12 hours after birth (with an allowable time error of 0.5 hour) were recorded. According to the presence or absence of brain injury and/or death during hospitalization, the neonates were divided into a poor prognosis group with 693 neonates and a good prognosis group with 779 neonates. The two groups were compared in the incidence of glucose metabolism disorders within 12 hours after birth and short-term prognosis.

RESULTS

Compared with the good prognosis group, the poor prognosis group had a significantly higher proportion of neonates from secondary hospitals (48.5% vs 42.6%, P<0.05) or with severe asphyxia (19.8% vs 8.1%, P<0.05) or hypothermia therapy (4.8% vs 1.5%, P<0.05), as well as a significantly higher incidence rate of disorder of glucose metabolism (18.8% vs 12.5%, P<0.05). Compared with the good prognosis group, the poor prognosis group had a significantly higher incidence rate of disorder of glucose metabolism at 1, 2, and 6 hours after birth (P<0.05). The multivariate logistic regression analysis showed that recurrent hyperglycemia (adjusted odds ratio=2.380, 95% confidence interval: 1.275-4.442, P<0.05) was an independent risk factor for poor prognosis in neonates with asphyxia.

CONCLUSIONS

Recurrent hyperglycemia in neonates with asphyxia may suggest poor short-term prognosis, and it is necessary to strengthen the early monitoring and management of the nervous system in such neonates.

Early Magnetic Resonance Imaging Predicts 30-Month Outcomes after Therapeutic Hypothermia for Neonatal Encephalopathy

OBJECTIVE

To evaluate the association of therapeutic hypothermia with magnetic resonance imaging (MRI) findings and 30-month neurodevelopment in term neonatal encephalopathy.

STUDY DESIGN

Cross-sectional analysis of 30-month neurodevelopment (IQR 19.0-31.4) in a prospective cohort of mild-to-severe neonatal encephalopathy imaged on day 4 (1993-2017 with institutional implementation of therapeutic hypothermia in 2007). MRI injury was classified as normal, watershed, or basal ganglia/thalamus. Abnormal motor outcome was defined as Bayley-II psychomotor developmental index <70, Bayley-III motor score <85 or functional motor deficit. Abnormal cognitive outcome was defined as Bayley-II mental developmental index <70 or Bayley-III cognitive score <85. Abnormal composite outcome was defined as abnormal motor and/or cognitive outcome, or death. The association of therapeutic hypothermia with MRI and outcomes was evaluated with multivariable logistic regression adjusted for propensity to receive therapeutic hypothermia.

RESULTS

Follow-up was available in 317 (78%) surviving children, of whom 155 (49%) received therapeutic hypothermia. Adjusting for propensity, therapeutic hypothermia was independently associated with decreased odds of abnormal motor (OR 0.15, 95% CI 0.06-0.40, P < .001) and cognitive (OR 0.11, 95% CI 0.04-0.33, P < .001) outcomes. This association remained statistically significant after adjustment for injury pattern. The predictive accuracy of MRI pattern for abnormal composite outcome was unchanged between therapeutic hypothermia-treated (area under the receiver operating curve 0.76; 95% CI 0.61-0.91) and untreated (area under the receiver operating curve 0.74; 95% CI 0.67-0.81) infants. The negative predictive value of normal MRI was high in therapeutic hypothermia-treated and untreated infants (motor 96% vs 90%; cognitive 99% vs 95%).

CONCLUSIONS

Therapeutic hypothermia is associated with lower rates of brain injury and adverse 30-month outcomes after neonatal encephalopathy. The predictive accuracy of MRI in the first week of life is unchanged by therapeutic hypothermia. Normal MRI remains reassuring for normal 30-month outcome after therapeutic hypothermia.

Proposing a care practice bundle for neonatal encephalopathy during therapeutic hypothermia

Neonates with neonatal encephalopathy (NE) often present with multi-organ dysfunction that requires multidisciplinary specialized management. Care of the neonate with NE is thus complex with interaction between the brain and various organ systems. Illness severity during the first days of birth, and not only during the initial hypoxia-ischemia event, is a significant predictor of adverse outcomes in neonates with NE treated with therapeutic hypothermia (TH). We thus propose a care practice bundle dedicated to support the injured neonatal brain that is based on the current best evidence for each organ system. The impact of using such bundle on outcomes in NE remains to be demonstrated.

Hyperglycemia associated with acute brain injury in neonatal encephalopathy

OBJECTIVE

To identify how alterations in glucose levels are associated with regional brain injury in neonatal encephalopathy.

METHODS

This was a prospective cohort study of 102 newborns with neonatal encephalopathy, with continuous glucose monitoring for 72 h. 97 (95%) completed 72 h of therapeutic hypothermia. Brain imaging around day 5 of life included diffusion tensor imaging and MR spectroscopy. Regions of interest were placed for both DTI and MR spectroscopy, and tractography of the optic radiation and corticospinal tract were evaluated. Linear regression models related each MR metric with minimum and maximum glucose values during each day of life, adjusting for 5-minute Apgar scores and umbilical artery pH.

RESULTS

Higher maximum glucose levels on the first day of life were associated with widespread changes in mean diffusivity in the anterior and posterior white matter, splenium of the corpus callosum, lentiform nucleus, pulvinar nucleus of the thalamus, posterior limb of the internal capsule, and optic radiations, thus including regions traditionally associated with hypoxia-ischemia or hypoglycemia. No associations were found between lower minimum glucose levels and DTI changes in any regions tested, or between glucose levels and MR spectroscopy.

CONCLUSIONS

In this cohort of neonatal encephalopathy with therapeutic hypothermia, higher maximal glucose on the first day of life was associated with widespread microstructural changes, but lower minimum glucose levels were not associated with changes in any of the regions tested. Long-term follow-up will determine if imaging findings translate to long-term outcomes.

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

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

Positive fluid balance is associated with death and severity of brain injury in neonates with hypoxic-ischemic encephalopathy

OBJECTIVE

To investigate the association between fluid balance during therapeutic hypothermia (TH) and severity of brain injury on magnetic resonance imaging (MRI) in neonates with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

This is a secondary analysis of data from a prospective observational study in neonates with HIE. Daily net positive fluid balance during TH was investigated for association with the adverse primary outcome of death or moderate-to-severe brain injury on MRI using multivariable logistic regression.

RESULTS

Of the 150 neonates included, 50 suffered adverse outcome and had significantly higher net positive fluid balance (53 vs. 19 ml/kg/day, p < 0.01) during first 24 hours of TH. Neonates with a net positive fluid balance (>25 ml/kg/day) at 24 hours of TH had 3.4 (95% CI 1.3-9) times higher odds of adverse outcome.

CONCLUSIONS

Positive fluid balance during TH in neonates with HIE is independently associated with death or moderate-to-severe brain injury on MRI.

European Resuscitation Council Guidelines 2021: Newborn resuscitation and support of transition of infants at birth

The European Resuscitation Council has produced these newborn life support guidelines, which are based on the International Liaison Committee on Resuscitation (ILCOR) 2020 Consensus on Science and Treatment Recommendations (CoSTR) for Neonatal Life Support. The guidelines cover the management of the term and preterm infant. The topics covered include an algorithm to aid a logical approach to resuscitation of the newborn, factors before delivery, training and education, thermal control, management of the umbilical cord after birth, initial assessment and categorisation of the newborn infant, airway and breathing and circulation support, communication with parents, considerations when withholding and discontinuing support.

Neonatal Hypoglycemia and Brain Vulnerability

Neonatal hypoglycemia is a common condition. A transient reduction in blood glucose values is part of a transitional metabolic adaptation following birth, which resolves within the first 48 to 72 h of life. In addition, several factors may interfere with glucose homeostasis, especially in case of limited metabolic stores or increased energy expenditure. Although the effect of mild transient asymptomatic hypoglycemia on brain development remains unclear, a correlation between severe and prolonged hypoglycemia and cerebral damage has been proven. A selective vulnerability of some brain regions to hypoglycemia including the second and the third superficial layers of the cerebral cortex, the dentate gyrus, the subiculum, the CA1 regions in the hippocampus, and the caudate-putamen nuclei has been observed. Several mechanisms contribute to neuronal damage during hypoglycemia. Neuronal depolarization induced by hypoglycemia leads to an elevated release of glutamate and aspartate, thus promoting excitotoxicity, and to an increased release of zinc to the extracellular space, causing the extensive activation of poly ADP-ribose polymerase-1 which promotes neuronal death. In this review we discuss the cerebral glucose homeostasis, the mechanisms of brain injury following neonatal hypoglycemia and the possible treatment strategies to reduce its occurrence.

Hyperglycaemia in the Newborn Infant. Physiology Verses Pathology

Hyperglycemia is common in newborns requiring intensive care, particularly in preterm infants, in sepsis and following perinatal hypoxia. The clinical significance, and optimal intervention strategy varies with context, but hyperglycaemia is associated with increased mortality and morbidity. The limited evidence for optimal clinical targets mean controversy remains regarding thresholds for intervention, and management strategies. The first consideration in the management of hyperglycaemia must be to ascertain potentially treatable causes. Calculation of the glucose infusion rate (GIR) to insure this is not excessive, is critical but the use of insulin is often helpful in the extremely preterm infant, but is associated with an increased risk of hypoglycaemia. The use of continuous glucose monitoring (CGM) has recently been demonstrated to be helpful in targeting glucose control, and reducing the risk from hypoglycaemia in the preterm infant. Its use in other at risk infants remains to be explored, and further studies are needed to provide a better understanding of the optimal glucose targets for different clinical conditions. In the future the combination of CGM and advances in computer algorithms, to provide intelligent closed loop systems, could allow a safer and more personalized approached to management.

[Newborn resuscitation and support of transition of infants at birth]

The European Resuscitation Council has produced these newborn life support guidelines, which are based on the International Liaison Committee on Resuscitation (ILCOR) 2020 Consensus on Science and Treatment Recommendations (CoSTR) for Neonatal Life Support. The guidelines cover the management of the term and preterm infant. The topics covered include an algorithm to aid a logical approach to resuscitation of the newborn, factors before delivery, training and education, thermal control, management of the umbilical cord after birth, initial assessment and categorisation of the newborn infant, airway and breathing and circulation support, communication with parents, considerations when withholding and discontinuing support.

Association of Routinely Measured Proinflammatory Biomarkers With Abnormal MRI Findings in Asphyxiated Neonates Undergoing Therapeutic Hypothermia

Background: The neuroprotective treatment effect of therapeutic hypothermia (TH) following perinatal asphyxia may be negatively influenced by neonatal sepsis and concomitant inflammation. We aimed to correlate routinely used blood biomarkers for perinatal sepsis in cooled asphyxiated newborns with MRI findings. Methods: Perinatal data was retrospectively collected from 67 cooled asphyxiated newborns. Levels of C-reactive protein (CRP), white blood cells and platelets were analyzed before, during and after TH. Interleukin-6 blood levels were analyzed before initiation of TH. Magnetic resonance imaging (MRI) on postnatal day 5-7 was used defining short-term outcome. Adverse outcome was defined as death or adverse MRI findings. Amplitude-integrated electroencephalography (aEEG) was additionally analyzed and correlated with short-term MRI outcome. Results: Forty-nine newborns had favorable short-term MRI outcome. Perinatal data referring to perinatal sepsis did not differ significantly between groups. IL-6 levels before initiation of TH and CRP levels on day three and after TH were significantly higher in newborns with adverse short-term MRI outcome. Males with adverse short-term MRI outcome had significantly increased CRP values at the end of the cooling phase. aEEG strongly correlated with short-term MRI outcome. Conclusion: Routinely used blood biomarkers may be helpful early identifying newborns at high risk of unfavorable outcome and in need of close neurodevelopmental follow-up.

Abnormalities in evoked potentials associated with abnormal glycemia and brain injury in neonatal hypoxic-ischemic encephalopathy

OBJECTIVE

To investigate how functional integrity of ascending sensory pathways measured by visual and somatosensory evoked potentials (VEP & SEP) is associated with abnormal glycemia and brain injury in newborns treated with hypothermia for hypoxic-ischemic encephalopathy (HIE).

METHODS

Fifty-four neonates ≥ 36 weeks gestational age with HIE underwent glucose testing, VEPs, SEPs, and magnetic resonance imaging (MRI) the first week of life. Minimum and maximum glucose values recorded prior to evoked potential (EP) testing were compared with VEP and SEP measures using generalized estimating equations. Relationships between VEP and SEP measures and brain injury on MRI were assessed.

RESULTS

Maximum glucose is associated with decreased P200 amplitude, and increased odds that N300 peak will be delayed/absent. Minimum glucose is associated with decreased P22 amplitude. Presence of P200 and N300 peaks is associated with decreased odds of brain injury in the visual processing pathway, with delayed/absent N300 peak associated with increased odds of brain injury in posterior white matter.

CONCLUSIONS

Deviations from normoglycemia are associated with abnormal EPs, and abnormal VEPs are associated with brain injury on MRI in cooled neonates with HIE.

SIGNIFICANCE

Glucose is a modifiable risk factor associated with atypical brain function in neonates with HIE despite hypothermia treatment.

[Effect of blood glucose on quantitative electroencephalography parameters in preterm infants]

OBJECTIVE

To study the value of quantitative electroencephalography (qEEG) in evaluating the effect of blood glucose on the brain function of preterm infants.

METHODS

The preterm infants who were admitted to the Department of Neonatology, The Third Xiangya Hospital of Central South University, from January to December 2019 were enrolled. According to the level of blood glucose, they were divided into group 1 (blood glucose <4.95 mmol/L), group 2 (blood glucose 4.95 to <6.60 mmol/L), group 3 (blood glucose 6.60 to <8.55 mmol/L), and group 4 (blood glucose ≥8.55 mmol/L). The changes in qEEG parameters were compared between groups, and a correlation analysis was performed for blood glucose and qEEG parameters.

RESULTS

A total of 39 preterm infants were enrolled (84 blood glucose measurements). Compared with group 4, the other three groups had significant increases in the total spectral power of each brain region and the absolute power of each frequency band in the frontal and occipital regions (P<0.05). The total spectral power, δ/θ ratio, and (δ+θ)/(α+β) ratio of each brain region were negatively correlated with blood glucose level, while the relative power of θ frequency band was positively correlated with blood glucose level (P<0.05).

CONCLUSIONS

With the change in blood glucose, there are significant changes in the total spectral power of each brain region, the power of each frequency band, and the frequency spectrum composition on qEEG in preterm infants. qEEG may therefore become an important tool to monitor the effect of abnormal blood glucose on brain function in preterm infants.

Effects of antenatal dexamethasone and hyperglycemia on cardiovascular adaptation to asphyxia in preterm fetal sheep

Antenatal glucocorticoids improve outcomes among premature infants but are associated with hyperglycemia, which can exacerbate hypoxic-ischemic injury. It is still unclear how antenatal glucocorticoids or hyperglycemia modulate fetal cardiovascular adaptations to severe asphyxia. In this study, preterm fetal sheep received either saline or 12 mg im maternal dexamethasone, followed 4 h later by complete umbilical cord occlusion (UCO) for 25 min. An additional cohort of fetuses received titrated glucose infusions followed 4 h later by UCO to control for the possibility that hyperglycemia contributed to the cardiovascular effects of dexamethasone. Fetuses were studied for 7 days after UCO. Maternal dexamethasone was associated with fetal hyperglycemia (P < 0.001), increased arterial pressure (P < 0.001), and reduced femoral (P < 0.005) and carotid (P < 0.05) vascular conductance before UCO. UCO was associated with bradycardia, femoral vasoconstriction, and transient hypertension. For the first 5 min of UCO, fetal blood pressure in the dexamethasone-asphyxia group was greater than saline-asphyxia (P < 0.001). However, the relative increase in arterial pressure was not different from saline-asphyxia. Fetal heart rate and femoral vascular conductance fell to similar nadirs in both saline and dexamethasone-asphyxia groups. Dexamethasone did not affect the progressive decline in femoral vascular tone or arterial pressure during continuing UCO. By contrast, there were no effects of glucose infusions on the response to UCO. In summary, maternal dexamethasone but not fetal hyperglycemia increased fetal arterial pressure before and for the first 5 min of prolonged UCO but did not augment the cardiovascular adaptations to acute asphyxia.

Continuous glucose monitoring profile during therapeutic hypothermia in encephalopathic infants with unfavorable outcome

BACKGROUND

The relation between glucose homeostasis and outcome in hypoxic-ischemic encephalopathy (HIE) is unclear. To investigate whether glucose abnormalities assessed by using continuous interstitial glucose monitoring (CGM) correlate with later neurological outcomes in HIE.

METHODS

Prospective cohort study recruiting full-term neonates who received therapeutic hypothermia for HIE. CGM devices were placed soon after birth and recorded glucose profile for 3 days. The association between hypoglycemia (≤50 mg/dL), hyperglycemia (>144 mg/dL) and primary outcome defined as death or moderate or severe disability was examined with generalized estimating equations adjusted for Apgar scores, umbilical artery pH and base deficit. Neurodevelopmental outcome was assessed between 18 and 24 months.

RESULTS

Fifty-four neonates had outcome data available for the analysis; 19 of them (35%) had adverse outcome. Longer duration of hypoglycemia (OR 7.1, 95% CI 1.8-20.3, P < 0.001) and hyperglycemia (OR 5.4, 95% CI 1.6-15.7, P < 0.001), a greater area under the hypoglycemic (OR 2.6, 95% CI 1.4-4.6, P = 0.04) and hyperglycemic (OR 6.4, 95% CI 1.9-16.3, P < 0.001) curve were significantly associated with adverse outcomes.

CONCLUSION

Both hyper and hypoglycemia may be associated with adverse outcome in neonates with HIE. Future studies are needed to assess their prognostic association with neurological outcome.

IMPACT

Glucose abnormalities during therapeutic hypothermia are associated with later neurological outcomes.Increased glucose variability correlates to the neurological outcome between 18 and 24 months.This study provides the first data on the continuous glucose profile in a group of HIE infants followed up to 2 years of age.Glucose homeostasis represents a key point in the management of HIE patients.Further research is needed to find the appropriate glycemic target in this population.

Real time continuous glucose monitoring in neonatal intensive care

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

Differences in patient characteristics and care practices between two trials of therapeutic hypothermia

BACKGROUND

The Induced Hypothermia (IH) and Optimizing Cooling (OC) trials for hypoxic-ischemic encephalopathy (HIE) had similar inclusion criteria. The rate of death/moderate-severe disability differed for the subgroups treated with therapeutic hypothermia (TH) at 33.5 °C for 72 h (44% vs. 29%, unadjusted p = 0.03). We aimed to evaluate differences in patient characteristics and care practices between the trials.

METHODS

We compared pre/post-randomization characteristics and care practices between IH and OC.

RESULTS

There were 208 patients in the IH trial, 102 cooled, and 364 in the OC trial, 95 cooled to 33.5 °C for 72 h. In OC, neonates were less ill, fewer had severe HIE, and the majority were cooled prior to randomization. Differences between IH and OC were observed in the adjusted difference in the lowest PCO₂ (+3.08 mmHg, p = 0.005) and highest PO₂ (-82.7 mmHg, p < 0.001). In OC, compared to IH, the adjusted relative risk (RR) of exposure to anticonvulsant prior to randomization was decreased (RR 0.58, (0.40-0.85), p = 0.005) and there was increased risk of exposure during cooling to sedatives/analgesia (RR 1.86 (1.21-2.86), p = 0.005).

CONCLUSION

Despite similar inclusion criteria, there were differences in patient characteristics and care practices between trials. Change in care practices over time should be considered when planning future neuroprotective trials.

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.

The neurointensive nursery: concept, development, and insights gained

PURPOSE OF REVIEW

With the advent of therapeutic hypothermia for treatment of hypoxic ischemic encephalopathy, and improvements in neuroimaging and bedside neuromonitoring, a new era of neonatal brain-focused care has emerged in recent years. We describe the development of the first neurointensive care nursery (NICN) as a model for comanagement of neonates with identified neurologic risk factors by a multidisciplinary team constituted of neurologists, neonatologists, specialized nurses, and others with the goal of optimizing management, preventing secondary injury and maximizing long-term outcomes.

RECENT FINDINGS

Optimizing brain metabolic environment and perfusion and preventing secondary brain injury are key to neurocritical care. This includes close management of temperature, blood pressure, oxygenation, carbon dioxide, and glucose levels. Early developmental interventions and involvement of physical and occupational therapy provide additional assessment information. Finally, long-term follow-up is essential for any neurocritical care program.

SUMMARY

The NICN model aims to optimize evidence-based care of infants at risk for neurologic injury. Results from ongoing hypothermia and neuroprotective trials are likely to yield additional treatments. New technologies, such as functional MRI, continuous neurophysiological assessment, and whole genomic approaches to rapid diagnosis may further enhance clinical protocols and neonatal precision medicine. Importantly, advances in neurocritical care improve our ability to provide comprehensive information when counseling families. Long-term follow-up data will determine if the NICN/Neuro-NICU provides enduring benefit to infants at risk for neurologic injury.