Small animal PET with spontaneous inhalation of 15O-labelled oxygen gases: Longitudinal assessment of cerebral oxygen metabolism in a rat model of neonatal hypoxic-ischaemic encephalopathy

Perinatal hypoxic-ischaemic encephalopathy (HIE) is the leading cause of irreversible brain damage resulting in serious neurological dysfunction among neonates. We evaluated the feasibility of positron emission tomography (PET) methodology with 15O-labelled gases without intravenous or tracheal cannulation for assessing temporal changes in cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRO2) in a neonatal HIE rat model. Sequential PET scans with spontaneous inhalation of 15O-gases mixed with isoflurane were performed over 14 days after the hypoxic-ischaemic insult in HIE pups and age-matched controls. CBF and CMRO2 in the injured hemispheres of HIE pups remarkably decreased 2 days after the insult, gradually recovering over 14 days in line with their increase found in healthy controls according to their natural maturation process. The magnitude of hemispheric tissue loss histologically measured after the last PET scan was significantly correlated with the decreases in CBF and CMRO2.This fully non-invasive imaging strategy may be useful for monitoring damage progression in neonatal HIE and for evaluating potential therapeutic outcomes.

Resting-state functional connectivity in children cooled for neonatal encephalopathy

Therapeutic hypothermia improves outcomes following neonatal hypoxic-ischaemic encephalopathy, reducing cases of death and severe disability such as cerebral palsy compared with normothermia management. However, when cooled children reach early school-age, they have cognitive and motor impairments which are associated with underlying alterations to brain structure and white matter connectivity. It is unknown whether these differences in structural connectivity are associated with differences in functional connectivity between cooled children and healthy controls. Resting-state functional MRI has been used to characterize static and dynamic functional connectivity in children, both with typical development and those with neurodevelopmental disorders. Previous studies of resting-state brain networks in children with hypoxic-ischaemic encephalopathy have focussed on the neonatal period. In this study, we used resting-state fMRI to investigate static and dynamic functional connectivity in children aged 6-8 years who were cooled for neonatal hypoxic-ischaemic without cerebral palsy [n = 22, median age (interquartile range) 7.08 (6.85-7.52) years] and healthy controls matched for age, sex and socioeconomic status [n = 20, median age (interquartile range) 6.75 (6.48-7.25) years]. Using group independent component analysis, we identified 31 intrinsic functional connectivity networks consistent with those previously reported in children and adults. We found no case-control differences in the spatial maps of these intrinsic connectivity networks. We constructed subject-specific static functional connectivity networks by measuring pairwise Pearson correlations between component time courses and found no case-control differences in functional connectivity after false discovery rate correction. To study the time-varying organization of resting-state networks, we used sliding window correlations and deep clustering to investigate dynamic functional connectivity characteristics. We found k = 4 repetitively occurring functional connectivity states, which exhibited no case-control differences in dwell time, fractional occupancy or state functional connectivity matrices. In this small cohort, the spatiotemporal characteristics of resting-state brain networks in cooled children without severe disability were too subtle to be differentiated from healthy controls at early school-age, despite underlying differences in brain structure and white matter connectivity, possibly reflecting a level of recovery of healthy resting-state brain function. To our knowledge, this is the first study to investigate resting-state functional connectivity in children with hypoxic-ischaemic encephalopathy beyond the neonatal period and the first to investigate dynamic functional connectivity in any children with hypoxic-ischaemic encephalopathy.

Enhancing 7-dehydrocholesterol suppresses brain ferroptosis and tissue injury after neonatal hypoxia-ischemia

Neonatal hypoxic-ischemic brain injury (HIBI) results in part from excess reactive oxygen species and iron-dependent lipid peroxidation (i.e. ferroptosis). The vitamin D precursor 7-dehydrocholesterol (7-DHC) may inhibit iron-dependent lipid peroxidation. Primary neurons underwent oxygen and glucose deprivation (OGD) injury and treatment with 7-DHC-elevating medications such as cariprazine (CAR) or vehicle. Postnatal day 9 mice underwent sham surgery or carotid artery ligation and hypoxia and received intraperitoneal CAR. In neurons, CAR administration resulted in significantly increased cell survival compared to vehicle controls, whether administered 48 h prior to or 30 min after OGD, and was associated with increased 7-DHC. In the mouse model, malondialdehyde and infarct area significantly increased after HIBI in the vehicle group, which were attenuated by post-treatment with CAR and were negatively correlated with tissue 7-DHC concentrations. Elevating 7-DHC concentrations with CAR was associated with improved cellular and tissue viability after hypoxic-ischemic injury, suggesting a novel therapeutic avenue.

Human Placenta-Derived Mesenchymal Stem Cells Improve Neurological Function in Rats with Intrauterine Hypoxic-Ischaemic Encephalopathy by Reducing Apoptosis and Inflammatory Reactions

BACKGROUND

Hypoxic-ischaemic encephalopathy (HIE) is a major cause of neonatal disability and mortality. Although hypothermia therapy offers some neuroprotection, the recovery of neurological function is limited. Therefore, new synergistic therapies are necessary to improve the prognosis. Mesenchymal stem cell-based therapy is emerging as a promising treatment option for HIE. In this study, we studied the therapeutic efficacy of human placenta-derived mesenchymal stem cells (PD-MSCs) in the HIE rat model and analyzed the underlying therapeutic mechanisms.

METHODS

Rats were divided into 6 groups (n = 9 for each) as follows: control, HIE model, HIE + normal saline, and HIE + PD-MSC transplantation at days 7, 14 and 28 postpartum. Following PD-MSC transplantation, neurological behavior was evaluated using rotarod tests, traction tests, and the Morris water maze test. The degree of brain tissue damage was assessed by histological examination and Nissl staining. Expression levels of apoptosis-related proteins and inflammatory factors were quantified by Western blotting and enzyme-linked immunosorbent assays. Immunofluorescence was used to investigate the ability of PD-MSCs to repair the morphology and function of hippocampal neurons with hypoxic-ischaemic (HI) injury.

RESULTS

PD-MSC transplantation enhanced motor coordination and muscle strength in HIE rats. This treatment also improved spatial memory ability by repairing pathological damage and preventing the loss of neurons in the cerebral cortex. The most effective treatment was observed in the HIE + PD-MSC transplantation at day 7 group. Expression levels of microtubule-associated protein-2 (MAP-2), B-cell lymphoma-2 (BCL-2), interleukin (IL)-10, and transforming growth factor (TGF -β1) were significantly higher in the HIE + PD-MSC treatment groups compared to the HIE group, whereas the levels of BCL-2-associated X protein (BAX), BCL-2-associated agonist of cell death (BAD), IL-1β and tumour necrosis factor α (TNF-α) were significantly lower.

CONCLUSIONS

We demonstrated that intravenous injection of PD-MSC at 7, 14 and 28 days after intrauterine HI damage in a rat model could improve learning, memory, and motor function, possibly by inhibiting apoptosis and inflammatory damage. These findings indicate that autologous PD-MSC therapy could have potential application for the treatment of HIE.

Higher parental education was associated with good cognitive outcomes in infants with hypoxic-ischaemic encephalopathy

AIM

Predicting neurodevelopmental outcomes in hypoxic-ischaemic encephalopathy (HIE) remains imprecise, despite advanced imaging and neurophysiological tests. We explored the predictive value of socio-economic status (SES).

METHODS

The cohort comprised 93 infants (59% male) with HIE, who had received therapeutic hypothermia. Patients underwent magnetic resonance imaging, and brain injuries were quantified using the Barkovich scoring system. Family SES was self-reported using a questionnaire. Adverse outcomes were defined as mild to severely delayed development with a score of ≤85 in any domain at 2 years of age, based on the Bayley Scales of Infant Development, Second Edition. Data are presented as odds ratios (OR) with 95% confidence intervals (95% CI).

RESULTS

Multiple regression modelling revealed that higher parental education was strongly associated with good cognitive development, when adjusted for gestational age, serum lactate and brain injuries (OR 2.20, 95% CI 1.16-4.36). The effect size of parental education (β = 0.786) was higher than one score for any brain injury using the Barkovich scoring system (β = -0.356). The literacy environment had a significant effect on cognitive development in the 21 infants who had brain injuries (OR 40, 95% CI 3.70-1352).

CONCLUSION

Parental education and the literacy environment influenced cognitive outcomes in patients with HIE.

Altered resting-state functional connectivity in newborns with hypoxic ischemic encephalopathy assessed using high-density functional near-infrared spectroscopy

Hypoxic-ischemic encephalopathy (HIE) results from a lack of oxygen to the brain during the perinatal period. HIE can lead to mortality and various acute and long-term morbidities. Improved bedside monitoring methods are needed to identify biomarkers of brain health. Functional near-infrared spectroscopy (fNIRS) can assess resting-state functional connectivity (RSFC) at the bedside. We acquired resting-state fNIRS data from 21 neonates with HIE (postmenstrual age [PMA] = 39.96), in 19 neonates the scans were acquired post-therapeutic hypothermia (TH), and from 20 term-born healthy newborns (PMA = 39.93). Twelve HIE neonates also underwent resting-state functional magnetic resonance imaging (fMRI) post-TH. RSFC was calculated as correlation coefficients amongst the time courses for fNIRS and fMRI data, respectively. The fNIRS and fMRI RSFC maps were comparable. RSFC patterns were then measured with graph theory metrics and compared between HIE infants and healthy controls. HIE newborns showed significantly increased clustering coefficients, network efficiency and modularity compared to controls. Using a support vector machine algorithm, RSFC features demonstrated good performance in classifying the HIE and healthy newborns in separate groups. Our results indicate the utility of fNIRS-connectivity patterns as potential biomarkers for HIE and fNIRS as a new bedside tool for newborns with HIE.

Deep brain stimulation of the central thalamus restores arousal and motivation in a zolpidem-responsive patient with akinetic mutism after severe brain injury

After severe brain injury, zolpidem is known to cause spectacular, often short-lived, restorations of brain functions in a small subgroup of patients. Previously, we showed that these zolpidem-induced neurological recoveries can be paralleled by significant changes in functional connectivity throughout the brain. Deep brain stimulation (DBS) is a neurosurgical intervention known to modulate functional connectivity in a wide variety of neurological disorders. In this study, we used DBS to restore arousal and motivation in a zolpidem-responsive patient with severe brain injury and a concomitant disorder of diminished motivation, more than 10 years after surviving hypoxic ischemia. We found that DBS of the central thalamus, targeted at the centromedian-parafascicular complex, immediately restored arousal and was able to transition the patient from a state of deep sleep to full wakefulness. Moreover, DBS was associated with temporary restoration of communication and ability to walk and eat in an otherwise wheelchair-bound and mute patient. With the use of magnetoencephalography (MEG), we revealed that DBS was generally associated with a marked decrease in aberrantly high levels of functional connectivity throughout the brain, mimicking the effects of zolpidem. These results imply that 'pathological hyperconnectivity' after severe brain injury can be associated with reduced arousal and behavioral performance and that DBS is able to modulate connectivity towards a 'healthier baseline' with lower synchronization, and, can restore functional brain networks long after severe brain injury. The presence of hyperconnectivity after brain injury may be a possible future marker for a patient's responsiveness for restorative interventions, such as DBS, and suggests that lower degrees of overall brain synchronization may be conducive to cognition and behavioral responsiveness.

Nutrition of Newborns with Hypoxic-Ischaemic Encephalopathy during Therapeutic Hypothermia - A Survey of Practice in Polish Neonatal Care Units

BACKGROUND

The nutritional practice for newborns with hypoxic-ischaemic encephalopathy during therapeutic hypothermia differs among Polish neonatal care units, as no guidelines are provided. We assessed the prevailing procedures.

MATERIAL AND METHODS

Data was collected through an anonymous, web-based questionnaire. We surveyed aspects of the current nutritional practices and the reasoning behind the choice of the feeding strategy.

RESULTS

Thirty-one responses were obtained (31/33, 94%). Based on participants' estimations, 342 newborns are diagnosed with hypoxic-ischaemic encephalopathy and qualified for therapeutic hypothermia annually. Among them, almost ⅓ is fed exclusively parenterally, while 71% both ways-parenterally and enterally. In the vast majority of units, the introduction of enteral nutrition takes place during the first 48 hours of therapeutic hypothermia, and breast milk is primarily provided, although with substantial first feeding volume differentiation (an average of 2,9 ml/kg (0,3 - 10ml/kg)). Adverse events, such as necrotising enterocolitis, sepsis, and glycemia level disturbances that derive from the initiation of enteral nutrition, are difficult to estimate as no official statistics are provided.

CONCLUSIONS

The majority of newborns after hypoxic-ischaemic encephalopathy treated with therapeutic hypothermia are fed both parenterally and enterally during the procedure, predominantly with expressed or donor breast milk. However, due to the lack of nutritional guidelines, significant variability of nutritional strategies concerning initiation time, type and volume of enteral feeds given is noted. Therefore, further studies are required to clarify feeding recommendations.

Apparent diffusion coefficient values can predict neuromotor outcome in term neonates with hypoxic-ischaemic encephalopathy

AIM

To determine the apparent diffusion coefficient (ADC) in brain structures during the first 2 weeks of life and its relation with neurological outcome for hypoxic-ischaemic encephalopathy (HIE) in term neonates.

METHODS

We retrospectively evaluated 56 term-born neonates. The ADC values were measured for 11 brain regions. The clinical outcomes at least 2 years of age were defined as normal outcome, mild disability and severe disability. The area under curves (AUCs) by ROC analysis were performed to predict the neurodevelopmental outcomes. The clinical outcomes were compared between favourable outcome and adverse outcome and also between normal outcome and unfavourable outcome.

RESULTS

Thirty-four patients were judged as normal outcome, 10 as mild disability and 12 as severe disability. When the clinical outcomes were compared between favourable outcome and adverse outcome, the AUC on the 1st week was highest value at the thalamus. When the clinical outcomes were compared between normal outcome and unfavourable outcome, the AUC on the 1st week was highest at the thalamus.

CONCLUSION

The ADC values in the thalamus in the 1st week can predict the neurological outcome. The ADC values in centrum semiovale on the 2nd week can be used to predict neurodevelopmental outcomes.

Hypoxic-ischaemic encephalopathy based on clinical signs and symptoms and associated factors among neonates, Southern Ethiopian public hospitals: a case-control study

Background

Hypoxic-ischaemic encephalopathy (HIE) is a severe condition that results from reduced oxygen supply and blood flow to the brain, leading to brain injury and potential long-term neurodevelopmental impairments. This study aimed to identify the maternal and neonatal factors associated with hypoxic-ischaemic encephalopathy among Neonates.

Methods

The authors conducted a case-control study in 15 public hospitals with 515 neonates and mothers (175 cases and 340 controls). The authors used a questionnaire and clinical records created and managed by Kobo software to collect data. The authors diagnosed hypoxic-ischaemic encephalopathy (HIE) by clinical signs and symptoms. The authors used logistic regression to identify HIE factors.

Results

Hypoxic-ischaemic encephalopathy (HIE) was associated with maternal education, ultrasound checkup, gestational age, delivery mode, and labour duration. Illiterate mothers [adjusted odds ratio (AOR)= 1.913, 95% CI: 1.177, 3.109], no ultrasound checkup (AOR= 1.859, 95% CI: 1.073, 3.221), preterm (AOR= 4.467, 95% CI: 1.993, 10.012) or post-term birth (AOR= 2.903, 95% CI: 1.325, 2.903), caesarean section (AOR= 7.569, 95% CI: 4.169, 13.741), and prolonged labour (AOR= 3.591, 95% CI: 2.067, 6.238) increased the incidence of HIE.

Conclusion

This study reveals the factors for hypoxic-ischaemic encephalopathy among neonates in Ethiopia. The authors found that neonates born to illiterate women, those who experienced prolonged labour, those whose mothers did not have ultrasound checkups during pregnancy, those delivered by caesarean section, and those born preterm, or post-term were more likely to develop hypoxic-ischaemic encephalopathy. These findings indicate that enhancing maternal education and healthcare services during pregnancy and delivery may positively reduce hypoxic-ischaemic encephalopathy among neonates.

Deep brain stimulation in disorders of consciousness: 10 years of a single center experience

Disorders of consciousness (DoC), namely unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), represent severe conditions with significant consequences for patients and their families. Several studies have reported the regaining of consciousness in such patients using deep brain stimulation (DBS) of subcortical structures or brainstem nuclei. Our study aims to present the 10 years' experience of a single center using DBS as a therapy on a cohort of patients with DoC. Eighty Three consecutive patients were evaluated between 2011 and 2022; entry criteria consisted of neurophysiological and neurological evaluations and neuroimaging examinations. Out of 83, 36 patients were considered candidates for DBS implantation, and 32 patients were implanted: 27 patients had UWS, and five had MCS. The stimulation target was the centromedian-parafascicular complex in the left hemisphere in hypoxic brain lesion or the one better preserved in patients with traumatic brain injury. The level of consciousness was improved in seven patients. Three out of five MCS patients emerged to full awareness, with the ability to interact and communicate. Two of them can live largely independently. Four out of 27 UWS patients showed consciousness improvement with two patients emerging to full awareness, and the other two reaching MCS. In patients with DoC lasting longer than 12 months following traumatic brain injury or 6 months following anoxic-ischemic brain lesion, spontaneous recovery is rare. Thus, DBS of certain thalamic nuclei could be recommended as a treatment option for patients who meet neurological, neurophysiological and neuroimaging criteria, especially in earlier phases, before occurrence of irreversible musculoskeletal changes. Furthermore, we emphasize the importance of cooperation between centers worldwide in studies on the potentials of DBS in treating patients with DoC.

Newborns with Favourable Outcomes after Perinatal Asphyxia Have Upregulated Glucose Metabolism-Related Proteins in Plasma

Hypoxic-ischaemic encephalopathy (HIE) is an important cause of morbidity and mortality globally. Although mild therapeutic hypothermia (TH) may improve outcomes in selected babies, the mechanism of action is not fully understood. A proteomics discovery study was carried out to analyse proteins in the plasma of newborns with HIE. Proteomic analysis of plasma from 22 newborns with moderate-severe HIE that had initially undergone TH, and relative controls including 10 newborns with mild HIE who did not warrant TH and also cord blood from 10 normal births (non-HIE) were carried out using the isobaric Tandem Mass Tag (TMT®) 10plexTM labelling with tandem mass spectrometry. A total of 7818 unique peptides were identified in all TMT10plexTM samples, translating to 3457 peptides representing 405 proteins, after applying stringent filter criteria. Apart from the unique protein signature from normal cord blood, unsupervised analysis revealed several significantly regulated proteins in the TH-treated moderate-severe HIE group. GO annotation and functional clustering revealed various proteins associated with glucose metabolism: the enzymes fructose-bisphosphate aldolase A, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate mutase 1, phosphoglycerate kinase 1, and pyruvate kinase PKM were upregulated in newborns with favourable (sHIE+) outcomes compared to newborns with unfavourable (sHIE-) outcomes. Those with favourable outcomes had normal MR imaging or mild abnormalities not predictive of adverse outcomes. However, in comparison to mild HIE and the sHIE- groups, the sHIE+ group had the additional glucose metabolism-related enzymes upregulated, including triosephosphate isomerase, α-enolase, 6-phosphogluconate dehydrogenase, transaldolase, and mitochondrial glutathione reductase. In conclusion, our plasma proteomic study demonstrates that TH-treated newborns with favourable outcomes have an upregulation in glucose metabolism. These findings may open new avenues for more effective neuroprotective therapy.

Volumetric apparent diffusion coefficient (ADC) histogram analysis of the brain in paediatric patients with hypoxic ischaemic encephalopathy

Purpose

To evaluate the whole brain, hippocampus, thalamus, and lentiform nucleus by volumetric apparent diffusion coefficient (ADC) histogram analysis in paediatric patients with hypoxic-ischaemic encephalopathy (HIE).

Material and methods

This retrospective study included 25 patients with HIE and 50 patients as the control group. Diffusion-weighted imaging was obtained at b-values of 1000 mm2/s. The histogram parameters of ADC values, including the mean, minimum, maximum, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles, as well as skewness, kurtosis, and variance were determined. The interclass correlation coefficient (ICC) was used to assess the inter-observer agreement.

Results

ADCmin, ADCmean, and ADCmax, as well as the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of ADC values for the HIE group were all lower than those of the control group (p < 0.001) in the volumetric histogram analysis of the hippocampus, thalamus, and lentiform nucleus. In the whole-brain histogram analysis, ADC min, and the 50th and 75th percentiles of ADC values did not differ significantly, while other parameters were lower in the HIE group. The ROC curve revealed that the ADC histogram parameters of the hippocampus provided the most accurate results for the diagnosis of HIE. The area under the curve (AUC) of the 95th percentile of ADC values was the highest (AUC = 0.915; cut-off 1.262 × 10-3 mm2/s; sensitivity 88% and specificity 84%).

Conclusions

Volumetric ADC histogram analysis of the whole brain, hippocampus, thalamus, and lentiform nucleus with b-values of 1000 mm2/s can serve as an imaging marker for determining HIE.

Altered biventricular function in neonatal hypoxic-ischaemic encephalopathy: a case-control echocardiographic study

BACKGROUND

In newborns with hypoxic-ischaemic encephalopathy, more profound altered right and left ventricular function has been associated with mortality or brain injury. Mechanisms underlying cardiac dysfunction in this population are thought to be related to the persistence of increased pulmonary vascular resistance and myocardial ischaemia. We sought to compare cardiac function in newborns with hypoxic-ischaemic encephalopathy to controls using echocardiography.

METHODS

We did a retrospective case-control study with moderate or severe hypoxic-ischaemic encephalopathy between 2008 and 2017. Conventional and speckle-tracking echocardiography measures were extracted to quantify right and left ventricular systolic and diastolic function. Fifty-five newborns with hypoxic-ischaemic encephalopathy were compared to 28 controls.

RESULTS

Hypoxic-ischaemic encephalopathy newborns had higher estimated systolic pulmonary pressure (62.5 ± 15.0 versus 43.8 ± 17.3 mmHg, p < 0.0001) and higher systolic pulmonary artery pressure/systolic blood pressure ratio [101 ± 16 (iso-systemic) versus 71 ± 27 (2/3 systemic range) %, p < 0.0001]. Tricuspid annular plane systolic excursion was decreased (7.5 ± 2.2 versus 9.0 ± 1.4 mm, p = 0.002), E/e' increased (7.9 ± 3.3 versus 5.8 ± 2.0, p = 0.01), and right ventricle-myocardial performance index increased (68.1 ± 21.5 versus 47.8 ± 9.5, p = 0.0001) in hypoxic-ischaemic encephalopathy. Conventional markers of left ventricle systolic function were similar, but e' velocity (0.059 ± 0.019 versus 0.070 ± 0.01, p = 0.03) and left ventricle-myocardial performance index were statistically different (77.9 ± 26.2 versus 57.9 ± 11.2, p = 0.001). The hypoxic-ischaemic encephalopathy group had significantly altered right and left ventricular deformation parameters by speckle-tracking echocardiography. Those with decreased right ventricle-peak longitudinal strain were more likely to have depressed left ventricle-peak longitudinal strain.

CONCLUSION

Newborns with hypoxic-ischaemic encephalopathy have signs of increased pulmonary pressures and altered biventricular systolic and diastolic function.

Engineered inhaled nanocatalytic therapy for ischemic cerebrovascular disease by inducing autophagy of abnormal mitochondria

Mitochondrial dysfunction and subsequent accumulation of reactive oxygen species (ROS) are key contributors to the pathology of ischemic cerebrovascular disease. Therefore, elimination of ROS and damaged mitochondria is crucial for the effective treatment of this disease. For this purpose, we designed an inhalation nanotherapeutic agent, P/D@Mn/Co3O4, to treat ischemic cerebrovascular disease. Mn/Co3O4 effectively removed excess ROS from cells, reduced acute cellular oxidative stress, and protected neural cells from apoptosis. Furthermore, it depleted the H+ surrounding mitochondria and depolarized the mitochondrial membrane potential, inducing mitophagy and eliminating abnormal mitochondria, thereby avoiding the continuous overproduction of ROS by eliminating the source of ROS regeneration. On intranasal administration, Mn/Co3O4 encapsulated by platelet membranes and 2,3-(dioxy propyl)-trimethylammonium chloride can bypass the blood-brain barrier, enter the brain through the trigeminal and olfactory pathways, and target inflammatory regions to remove ROS and damaged mitochondria from the lesion area. In rat models of stroke and vascular dementia, P/D@Mn/Co3O4 effectively inhibited the symptoms of acute and chronic cerebral ischemia by scavenging ROS and damaged mitochondria in the affected area. Our findings indicate that the nanotherapeutic agent developed in this study can be used for the effective treatment of ischemic cerebrovascular disease.

Mechanisms underlying pathological cortical bursts during metabolic depletion

Cortical activity depends upon a continuous supply of oxygen and other metabolic resources. Perinatal disruption of oxygen availability is a common clinical scenario in neonatal intensive care units, and a leading cause of lifelong disability. Pathological patterns of brain activity including burst suppression and seizures are a hallmark of the recovery period, yet the mechanisms by which these patterns arise remain poorly understood. Here, we use computational modeling of coupled metabolic-neuronal activity to explore the mechanisms by which oxygen depletion generates pathological brain activity. We find that restricting oxygen supply drives transitions from normal activity to several pathological activity patterns (isoelectric, burst suppression, and seizures), depending on the potassium supply. Trajectories through parameter space track key features of clinical electrophysiology recordings and reveal how infants with good recovery outcomes track toward normal parameter values, whereas the parameter values for infants with poor outcomes dwell around the pathological values. These findings open avenues for studying and monitoring the metabolically challenged infant brain, and deepen our understanding of the link between neuronal and metabolic activity.

Prolonged requirements for mechanical ventilation and tube feeding support predicted 18-month outcomes for neonatal encephalopathy

AIM

We evaluated the predictive ability of prolonged requirements for mechanical ventilation or tube feeding support for 18-month composite outcomes in infants with hypoxic-ischaemic encephalopathy treated with hypothermia.

METHODS

This retrospective, nationwide, observational study focused on newborn infants registered in Japan's Baby Cooling Registry between 1 January 2012 and 31 December 2016. The adverse outcomes were defined as death or survival with cerebral palsy, visual or auditory impairment or the requirement for mechanical ventilation or tube feeding at 18 months of age.

RESULTS

Adverse outcomes occurred in 165 (28%) of the 591 children in the final cohort. These were predicted by prolonged dependence on mechanical ventilation or tube feeding for more than seven and more than 14 days. The respective values were positive predictive value 0.34 (95% CI 0.33-0.34) and 0.60 (95% CI 0.56-0.62), negative predictive value 0.97 (95% CI 0.91-0.99) and 0.93 (95% CI 0.90-0.95) and area under the curve 0.59 (95% CI 0.54-0.64) and 0.81 (95% CI 0.77-0.85).

CONCLUSION

Prolonged dependence on mechanical ventilation or tube feeding for more than 14 days may be useful in predicting 18-month outcomes in newborn infants who have received therapeutic hypothermia.

Cooling strategies during neonatal transport for hypoxic-ischaemic encephalopathy

AIM

We reviewed the literature on cooling methods during transport of newborn infants with hypoxic-ischaemic encephalopathy (HIE) born in a non-tertiary centre and transferred to a neonatal intensive care unit for therapeutic hypothermia.

METHODS

The electronic databases CENTRAL, MEDLINE, Embase, CINAHL, and Scopus were searched from inception up to 8 March 2022 for studies comparing cooling versus no cooling, active versus passive cooling, and servo-controlled versus non-servo-controlled cooling. Odds ratio and confidence of interval were calculated for dichotomous outcomes and mean difference and confidence interval for continuous outcomes.

RESULTS

The final analysis included 14 studies, 1 randomised and 13 non-randomised, involving 1098 newborn infants. Compared with the other cooling methods, servo-controlled active cooling was more likely to maintain body temperature within the target range of 33°C-34°C on arrival at a neonatal intensive care unit: odds ratio 13.58, 95% confidence interval 4.32-42.66, risk difference 0.33, 95% confidence interval 0.19-0.46; 224 participants; three studies; I² 0%. The certainty of evidence was low. Only five studies reported mortality rates.

CONCLUSION

Servo-controlled active cooling may be the preferred method during transport of newborn infants with HIE. A future area of focus should be long-term neurodevelopmental outcomes after servo-controlled active cooling.

Neonatal EEG graded for severity of background abnormalities in hypoxic-ischaemic encephalopathy

This report describes a set of neonatal electroencephalogram (EEG) recordings graded according to the severity of abnormalities in the background pattern. The dataset consists of 169 hours of multichannel EEG from 53 neonates recorded in a neonatal intensive care unit. All neonates received a diagnosis of hypoxic-ischaemic encephalopathy (HIE), the most common cause of brain injury in full term infants. For each neonate, multiple 1-hour epochs of good quality EEG were selected and then graded for background abnormalities. The grading system assesses EEG attributes such as amplitude, continuity, sleep-wake cycling, symmetry and synchrony, and abnormal waveforms. Background severity was then categorised into 4 grades: normal or mildly abnormal EEG, moderately abnormal EEG, majorly abnormal EEG, and inactive EEG. The data can be used as a reference set of multi-channel EEG for neonates with HIE, for EEG training purposes, or for developing and evaluating automated grading algorithms.

Clinical Characteristics and Risk Factors of Neonatal Hypoxic-Ischaemic Encephalopathy and Its Associated Neurodevelopmental Outcomes During the First Two Years of Life: A Retrospective Study in Saudi Arabia

Objective

This study aimed to determine the clinical characteristics and factors associated with neonatal hypoxic-ischaemic encephalopathy (HIE) and its neurodevelopmental outcomes.

Methods

We conducted retrospective case-control research to investigate the clinical and labour-related risk factors for HIE. In addition, a single-centre cohort study was conducted on infants with HIE to describe their neurodevelopment from birth to 24 months. For this investigation, cases with a diagnosis of HIE who were born at King Abdullah Children's Specialist Hospital (KASCH), Riyadh, Saudi Arabia, between 2015 and 2019 were identified and matched with controls from the same facility (1:4). Each case's clinical information was extracted using electronic medical records. In addition, 24-month follow-up HIE cases were included in a cohort study to describe their neurodevelopmental outcomes.

Results

The sample includes 60 infants diagnosed with HIE and 234 infants serving as controls, with a mean gestational age of 38.8 weeks (SD 1.6) and a predominance of males (56.4%). Around one-third of the HIE cases (36.6%) had moderate HIE (stage 2), whereas 35.1% of infants had severe HIE (stage 3), according to Sarnat staging. Compared to the control group, children with HIE were twice as likely to be born to mothers with maternal comorbidities and more likely to have prepartum and intrapartum complications. A 24-month follow-up of neurodevelopmental outcomes for HIE babies revealed that approximately 24% exhibited delays in gross motor skill development, 22% in fine motor skill development, 33% in language skill development, and 22% in social skill development.

Conclusion

In the HIE group, maternal comorbidities and prepartum or intrapartum complications were more common. The severity grade of HIE can be used to predict neurodevelopmental consequences. Enhancing patient care and rehabilitation requires a minimum of 24 months of neurodevelopmental follow-up.

Cerebral visual impairment in children: Multicentric study determining the causes, associated neurological and ocular findings, and risk factors for severe vision impairment

Purpose

To evaluate the causes, associated neurological and ocular findings in children with cerebral visual impairment (CVI), and to identify risk factors for severe vision impairment.

Methods

A multicenter, retrospective, cross-sectional analysis was carried out from January 2017 to December 2019 on patients less than 16 years of age with a diagnosis of CVI.

Results

A total of 405 patients were included of which 61.2% were male and 38.8% were female. The median age at presentation was 4 years (range 3 months to 16 years). Antenatal risk factors were present in 14% of the cases. The most common cause of CVI was hypoxic-ischemic encephalopathy (35.1%), followed by seizure associated with brain damage (31.3%). The most common neurological finding was seizure (50.4%), followed by cerebral palsy (13.6%). Associated ophthalmological findings were significant refractive error (63.2%), esotropia (22.2%), exotropia, (38%), nystagmus (33.3%), and optic nerve atrophy (25.9%). Severe visual impairment (<20/200) was associated with optic atrophy (odds ratio: 2.9, 95% confidence interval: 1.4-6.0; P = 0.003) and seizure disorder (odds ratio: 1.9, 95% confidence interval: 1.2-3.3; P = 0.012).

Conclusion

The various ophthalmic, neurological manifestations and etiologies could guide the multidisciplinary team treating the child with CVI in understanding the visual impairment that affects the neuro development of the child and in planning rehabilitation strategies.

Vascular endothelium deploys caveolin-1 to regulate oligodendrogenesis after chronic cerebral ischemia in mice

Oligovascular coupling contributes to white matter vascular homeostasis. However, little is known about the effects of oligovascular interaction on oligodendrocyte precursor cell (OPC) changes in chronic cerebral ischemia. Here, using a mouse of bilateral carotid artery stenosis, we show a gradual accumulation of OPCs on vasculature with impaired oligodendrogenesis. Mechanistically, chronic ischemia induces a substantial loss of endothelial caveolin-1 (Cav-1), leading to vascular secretion of heat shock protein 90α (HSP90α). Endothelial-specific over-expression of Cav-1 or genetic knockdown of vascular HSP90α restores normal vascular-OPC interaction, promotes oligodendrogenesis and attenuates ischemic myelin damage. miR-3074(-1)-3p is identified as a direct inducer of Cav-1 reduction in mice and humans. Endothelial uptake of nanoparticle-antagomir improves myelin damage and cognitive deficits dependent on Cav-1. In summary, our findings demonstrate that vascular abnormality may compromise oligodendrogenesis and myelin regeneration through endothelial Cav-1, which may provide an intercellular mechanism in ischemic demyelination.

Communication skills in children aged 6-8 years, without cerebral palsy cooled for neonatal hypoxic-ischemic encephalopathy

We assessed communication skills of 48 children without cerebral palsy (CP) treated with therapeutic hypothermia (TH) for neonatal hypoxic-ischemic encephalopathy (HIE) (cases) compared to 42 controls at early school-age and examined their association with white matter diffusion properties in both groups and 18-month Bayley-III developmental assessments in cases. Parents completed a Children's Communication Checklist (CCC-2) yielding a General Communication Composite (GCC), structural and pragmatic language scores and autistic-type behavior score. GCC ≤ 54 and thresholds of structural and pragmatic language score differences defined language impairment. Using tract-based spatial statistics (TBSS), fractional anisotropy (FA) was compared between 31 cases and 35 controls. Compared to controls, cases had lower GCC (p = 0.02), structural (p = 0.03) and pragmatic language score (p = 0.04) and higher language impairments (p = 0.03). GCC correlated with FA in the mid-body of the corpus callosum, the cingulum and the superior longitudinal fasciculus (p < 0.05) in cases. Bayley-III Language Composite correlated with GCC (r = 0.34, p = 0.017), structural (r = 0.34, p = 0.02) and pragmatic (r = 0.32, p = 0.03) language scores and autistic-type behaviors (r = 0.36, p = 0.01).

Short-term outcome of perinatal hypoxic-ischaemic encephalopathy at Chiang Mai University Hospital, Thailand: a 15-year retrospective study

BACKGROUND

The outcome of perinatal hypoxic-ischaemic encephalopathy (HIE) in middle-to-low-income countries varies between regions.

OBJECTIVES

To determine the mortality and morbidity, and factors influencing the deaths of infants with perinatal HIE.

METHODS

A retrospective study was conducted at Chiang Mai University Hospital, Thailand. Perinatal HIE infants of >35 weeks gestation, birthweight ≥2000 g and admitted during 2005-2019 were reviewed. Baseline Characteristics, clinical course and outcome at discharge were compared between the period before and after initiation of therapeutic hypothermia (TH). Risk of death in HIE infants who underwent TH was identified.

RESULTS

A total of 162 HIE infants were included. Compared to the period before TH initiation, the mortality rate was significantly decreased in the TH period. (27% vs. 12.8%, p=0.04) Among 100 HIE infants who underwent TH, the mortality rates was 14%(14/100), of whom 2.5% (2/76) and 50% (12/24) were in the moderate and severe HIE groups. Apgar score at 5 mins ≤1, severe HIE, seizures, hypoglycaemia, organ involvement ≥ five sites, ammonia ≥100 umol/L, lactate ≥14 mmol/L, and requirement for two or more inotropic drugs were risks of death. Multivariate analysis demonstrated that severe HIE (aOR 732.8, 95% CI 4.7-114643, p=0.01) and a need for two or more inotropic drugs (aOR 45.7, 95% CI 1.5-1040, p=0.029) were significant factors for mortality.

CONCLUSION

In the period of TH, perinatal HIE infants had decreased mortality. Severe HIE and a need for two or more inotropic drugs were associated with death in the infant with HIE who underwent TH.Abbreviations: AED: anti-epileptic drug; BW, birthweight; CI: confidence interval; CMU: Chiang Mai University; EEG: electro-encephalogram; GA: gestational age; HIE: hypoxic-ischaemic encephalopathy; IQR: interquartile range; NICU: neonatal intensive care unit; SD: standard deviation; TH: therapeutic hypothermia.

Proteomic profiles in cerebrospinal fluid predicted death and disability in term infants with perinatal asphyxia: A pilot study

Aim

Perinatal asphyxia, resulting in hypoxic‐ischaemic encephalopathy (HIE), has been associated with high mortality rates and severe lifelong neurodevelopmental disabilities. Our aim was to study the association between the proteomic profile in cerebrospinal fluid (CSF) and the degree of HIE and long‐term outcomes.

Methods

We prospectively enrolled 18‐term born infants with HIE and 10‐term born controls between 2000 and 2004 from the Karolinska University Hospital. An antibody suspension bead array and FlexMap3D analysis was used to characterise 178 unique brain‐derived and inflammation associated proteins in their CSF.

Results

Increased CSF concentrations of several brain‐specific proteins were observed in the proteome of HIE patients compared with the controls. An upregulation of neuroinflammatory pathways was also noted and this was confirmed by pathway analysis. Principal component analysis revealed a gradient from favourable to unfavourable HIE grades and outcomes. The proteins that provided strong predictors were structural proteins, including myelin basic protein and alpha‐II spectrin. The functional proteins included energy‐related proteins like neuron‐specific enolase and synaptic regulatory proteins. Increased CSF levels of 51 proteins correlated with adverse outcomes in infants with HIE.

Conclusion

Brain‐specific proteins and neuroinflammatory mediators in CSF may predict HIE degrees and outcomes after perinatal asphyxia.

Profile of minor neurological findings after perinatal asphyxia

Aim

To characterise the spectrum of findings in sequential neurological examinations, general movements (GM) assessment and magnetic resonance imaging (MRI) of infants with perinatal asphyxia.

Methods

The prospective cohort study of term infants with perinatal asphyxia treated at Helsinki University Hospital's neonatal units in 2016–2020 used Hammersmith Neonatal Neurological Examination (HNNE) and brain MRI at 2 weeks and Hammersmith Infant Neurological Examination (HINE) and GM assessment at 3 months of age.

Results

Analysis included 50 infants: 33 displaying perinatal asphyxia without hypoxic‐ischaemic encephalopathy (HIE), seven with HIE1 and 10 with HIE2. Of the infants with atypical HNNE findings, 24/25 perinatal asphyxia without HIE cases, 5/6 HIE1 cases and all 10 HIE2 cases showed atypical findings in the HINE. The HINE identified atypical spontaneous movements significantly more often in infants with white matter T2 hyperintensity.

Conclusion

In this cohort, most infants with perinatal asphyxia, with or without HIE, presented atypical neurological findings in sequential examinations. The profile of neurological findings for children with perinatal asphyxia without HIE resembled that of children with HIE. White matter T2 hyperintensity was associated with atypical spontaneous movements in the HINE and was a frequent MRI finding also in perinatal asphyxia without HIE.

Acute kidney injury in infants with hypothermia-treated hypoxic-ischaemic encephalopathy: An observational population-based study

AIM

To describe incidence and outcome of acute kidney injury (AKI) in infants with hypothermia-treated hypoxic-ischaemic encephalopathy (HIE).

METHODS

This observational population-based study included all term and near-term infants with hypothermia-treated HIE born between 2007 and 2009 in greater Stockholm. The KDIGO definition modified for neonatal patients was used to identify infants with AKI. We analysed association between AKI and neonatal morbidity/mortality. Furthermore, we calculated estimated glomerular filtration rate (eGFR) at the age of 10-12 years.

RESULTS

Out of 83,939 live births in the Stockholm region, 66 infants underwent hypothermia treatment due to HIE. Out of 65 included infants, 45% suffered AKI. Degree of AKI correlated with HIE severity. One infant needed kidney replacement therapy; others were treated conservatively. AKI was associated with increased mortality and need for blood products (p < 0.05). eGFR at age 10-12 years was available for 72% of survivors. Nine children (21%) had subnormal eGFR, with no difference between those with and without a history of neonatal AKI.

CONCLUSION

Despite therapeutic hypothermia, AKI remains a common complication in infants with HIE and is associated with increased neonatal mortality. Twenty-one per cent of children had subnormal eGFR at 10-12 years, highlighting the need for long-term follow-up of renal function.

Cardiotocography and Clinical Risk Factors in Early Term Labor: A Retrospective Cohort Study Using Computerized Analysis With Oxford System

OBJECTIVE

The role of cardiotocography (CTG) in fetal risk assessment around the beginning of term labor is controversial. We used routinely collected clinical data in a large tertiary hospital to investigate whether infants with "severe compromise" at birth exhibited fetal heart rate abnormalities in their first-hour CTGs and/or other clinical risks, recorded as per routine care.

MATERIALS AND METHODS

Retrospective data from 27,927 parturitions (single UK tertiary site, 2001-2010) were analyzed. Cases were included if the pregnancy was singleton, ≥36 weeks' gestation, cephalic presentation, and if they had routine intrapartum CTG as per clinical care. Cases with congenital abnormalities, planned cesarean section (CS), or CS for reasons other than "presumed fetal compromise" were excluded. We analyzed first-hour intrapartum CTG recordings, using intrapartum Oxford System (OxSys) computer-based algorithms. To reflect the effect of routine clinical care, the data was stratified into three exclusive groups: infants delivered by CS for "presumed fetal compromise" within 2 h of starting the CTG (Emergency CS, n = 113); between 2 and 5 h of starting the CTG (Urgent CS, n = 203); and the rest of deliveries (Others, n = 27,611). First-hour CTG and clinical characteristics were compared between the groups, sub-divided to those with and without severe compromise: a composite outcome of stillbirth, neonatal death, neonatal seizures, encephalopathy, resuscitation followed by ≥48 h in neonatal intensive care unit. Two-sample t-test, X² test, and Fisher's exact test were used for analysis.

RESULTS

Compared to babies without severe compromise, those with compromise had significantly higher proportion of cases with baseline fetal heart rate ≥150 bpm; non-reactive trace; reduced long-term and short-term variability; decelerative capacity; and no accelerations in the first-hour CTG across all groups. Prolonged decelerations(≥3 min) were also more common. Thick meconium and small for gestational age were consistently more common in compromised infants across all groups. There was more often thick meconium, maternal fever ≥38 C, sentinel events, and other clinical risk factors in the Emergency CS and Urgent CS compared to the Others group.

CONCLUSION

A proportion of infants born with severe compromise had significantly different first-hour CTG features and clinical risk factors.

Preclinical assessment of thrombin-preconditioned human Wharton's jelly-derived mesenchymal stem cells for neonatal hypoxic-ischaemic brain injury

Hypoxic-ischaemic encephalopathy (HIE) is a type of brain injury affecting approximately 1 million newborn babies per year worldwide, the only treatment for which is therapeutic hypothermia. Thrombin-preconditioned mesenchymal stem cells (MSCs) exert neuroprotective effects by enriching cargo contents and boosting exosome biogenesis, thus showing promise as a new therapeutic strategy for HIE. This study was conducted to evaluate the tissue distribution and potential toxicity of thrombin-preconditioned human Wharton's jelly-derived mesenchymal stem cells (th-hWJMSCs) in animal models before the initiation of clinical trials. We investigated the biodistribution, tumorigenicity and general toxicity of th-hWJMSCs. MSCs were administered the maximum feasible dose (1 × 105 cells/10 µL/head) once, or at lower doses into the cerebral ventricle. To support the clinical use of th-hWJMSCs for treating brain injury, preclinical safety studies were conducted in newborn Sprague-Dawley rats and BALB/c nude mice. In addition, growth parameters were evaluated to assess the impact of th-hWJMSCs on the growth of newborn babies. Our results suggest that th-hWJMSCs are non-toxic and non-tumorigenic in rodent models, survive for up to 7 days in the brain and hold potential for HIE therapy.

EEG microstate in obstructive sleep apnea patients

Obstructive sleep apnea (OSA) is a common sleep respiratory disease. Previous studies have found that the wakefulness electroencephalogram (EEG) of OSA patients has changed, such as increased EEG power. However, whether the microstates reflecting the transient state of the brain is abnormal is unclear during obstructive hypopnea (OH). We investigated the microstates of sleep EEG in 100 OSA patients. Then correlation analysis was carried out between microstate parameters and EEG markers of sleep disturbance, such as power spectrum, sample entropy and detrended fluctuation analysis (DFA). OSA_OH patients showed that the microstate C increased presence and the microstate D decreased presence compared to OSA_withoutOH patients and controls. The fifth microstate E appeared during N1-OH, but the probability of other microstates transferring to microstate E was small. According to the correlation analysis, OSA_OH patients in N1-OH showed that the microstate D was positively correlated with delta power, and negatively correlated with beta and alpha power; the transition probability of the microstate B → C and E → C was positively correlated with alpha power. In other sleep stages, the microstate parameters were not correlated with power, sample entropy and FDA. We might interpret that the abnormal transition of brain active areas of OSA patients in N1-OH stage leads to abnormal microstates, which might be related to the change of alpha activity in the cortex.

Neurodevelopmental outcome in neonates with hypoxic-ischaemic encephalopathy managed with therapeutic hypothermia in a tertiary-level public hospital outside an intensive care unit setting

BACKGROUND

Management of hypoxic-ischaemic encephalopathy (HIE) by therapeutic hypothermia (TH) is a major challenge in low- and middle-income countries (LMIC) because of the limited resources. Clinicians in LMIC offer this intervention outside neonatal intensive care units (NICU). The effect of this practice on neurodevelopmental outcome is not well known.

AIM

To determine neurodevelopmental outcome in neonates with HIE managed with TH outside NICU settings.

METHODS

: This was a retrospective descriptive study of neonates with HIE managed with TH and followed up for neurodevelopmental assessment at 12 and 18-24 months postnatal age. Patients were reviewed over a 24-month period. Outcome at 12 and 18-24 months was compared.

RESULTS

Of 178 neonates with HIE attending the clinic, there was information on TH for 155 (87.1%), 113 of whom (72.9%) received TH. HIE was moderate in 88% and severe in 10%. Twenty-seven (23.9%) and 16 (14.1%) were assessed at one time-point at 12 or 18-24 months, respectively, 40 (35.3%) at both time-points, and 30 (26.6%) were not assessed. At 18-24 months, 32% had moderate-to-severe disability compared with 6% at 12 months, with the sensitivity and specificity of assessment at 12 months being 50% and 100%, respectively. The disability attrition rate at 18-24 months was 50%.

CONCLUSIONS

The relatively low prevalence of disability (32%) at 18-24 months suggests that use of TH in a Level 2 nursery is feasible and possibly beneficial. More studies are needed to confirm these findings.

ABBREVIATIONS

aEEG: amplitude electroencephalogram; CP: cerebral palsy; GMDS: Griffiths mental developmental scales; GQ: general quotient; HIC: high-income countries; HIE: hypoxic-ischaemic encephalopathy; LMIC: low- and middle-income countries; LTFU: loss to follow-up; NICU: neonatal intensive care unit; TH: therapeutic hypothermia; TOBY: total body hypothermia.

An observational study of sleep in childhood post-neonatal encephalopathy

AIM

Neonatal encephalopathy (NE) is associated with altered cognitive, motor, sensory abilities and behavioural outcomes. This case-control study aimed to assess whether Quality of Life (QoL) and sleep disorders are affected in older children following NE compared to age-matched controls.

METHODS

Children at school-age post-NE were recruited and compared to age-matched controls. Sleep and QoL were assessed with the Pediatric Quality of Life Inventory and the Child Sleep Habit Questionnaire.

RESULTS

One hundred children were recruited with an age range of 4-6 years, including children post-NE (n=45) and age-matched controls (n = 55). Significantly higher pathological sleep scores were evident in 58% of children post-NE compared to controls (43.8 vs 40.2; p = 0.001). Children post-NE had increased bedtime resistance (p = 0.028) and sleep anxiety (p = 0.01) compared to controls. Children in the post-NE group had lower total QoL scores versus controls (mean score 82.5 vs 95.8; p < 0.01). Children with mild NE also had lower total QoL scores than controls (90.0 vs 95.8, p = 0.003). There was a strong correlation between low QoL with high total sleep scores (Rho 0.339, p = 0.014).

CONCLUSION

There were high rates of sleep issues in school-aged children with mild and moderate-severe NE. Consideration and management of sleep problems may improve QoL in childhood post-NE.

Altered inflammasome activation in neonatal encephalopathy persists in childhood

Neonatal encephalopathy (NE) is characterized by altered neurological function in term infants and inflammation plays an important pathophysiological role. Inflammatory cytokines interleukin (IL)‐1β, IL‐1ra and IL‐18 are activated by the nucleotide‐binding and oligomerization domain (NOD)‐, leucine‐rich repeat domain (LRR)‐ and NOD‐like receptor protein 3 (NLRP3) inflammasome; furthermore, we aimed to examine the role of the inflammasome multiprotein complex involved in proinflammatory responses from the newborn period to childhood in NE. Cytokine concentrations were measured by multiplex enzyme‐linked immunosorbent assay (ELISA) in neonates and children with NE in the absence or presence of lipopolysaccharide (LPS) endotoxin. We then investigated expression of the NLRP3 inflammasome genes, NLRP3, IL‐1β and ASC by polymerase chain reaction (PCR). Serum samples from 40 NE patients at days 1 and 3 of the first week of life and in 37 patients at age 4–7 years were analysed. An increase in serum IL‐1ra and IL‐18 in neonates with NE on days 1 and 3 was observed compared to neonatal controls. IL‐1ra in NE was decreased to normal levels at school age, whereas serum IL‐18 in NE was even higher at school age compared to school age controls and NE in the first week of life. Percentage of LPS response was higher in newborns compared to school‐age NE. NLRP3 and IL‐1β gene expression were up‐regulated in the presence of LPS in NE neonates and NLRP3 gene expression remained up‐regulated at school age in NE patients compared to controls. Increased inflammasome activation in the first day of life in NE persists in childhood, and may increase the window for therapeutic intervention.

Mammillary body atrophy and other MRI correlates of school-age outcome following neonatal hypoxic-ischemic encephalopathy

The mammillary bodies (MB) and hippocampi are important for memory function and are often affected following neonatal hypoxic ischemic encephalopathy (HIE). The aim of this study was to assess neurodevelopmental outcome in 10-year-old children with HIE with and without therapeutic hypothermia. Additional aims were to assess the associations between MB atrophy, brain volumes (including the hippocampi), white matter microstructure and neurodevelopmental outcome at school-age. Ten-year-old children with HIE were included, who were treated with therapeutic hypothermia (n = 22) or would have qualified but were born before this became standard of care (n = 28). Children completed a neuropsychological and motor assessment and MRI. Mammillary bodies were scored as normal or atrophic at 10 years. Brain volumes were segmented on childhood MRI and DTI scans were analysed using tract-based spatial statistics. Children with HIE suffered from neurocognitive and memory problems at school-age, irrespective of hypothermia. Hippocampal volumes and MB atrophy were associated with total and performance IQ, processing speed and episodic memory in both groups. Normal MB and larger hippocampi were positively associated with global fractional anisotropy. In conclusion, injury to the MB and hippocampi was associated with neurocognition and memory at school-age in HIE and might be an early biomarker for neurocognitive and memory problems.

Severe neurological nicotine intoxication by e-cigarette liquids: Systematic literature review

Electronic cigarettes are a popular, easily purchased, alternative source of nicotine that is considered safer than conventional tobacco. However, Intentional or accidental exposure to e-liquid substances, mainly nicotine, can lead to serious, potentially fatal toxicity. Emergency and critical care physicians should keep in mind acute intoxication of this poison with a biphasic toxic syndrome. We highlight its potentially fatal outcome and suggest monitoring the adverse effects of nicotine according to a multimodal protocol integrating somatosensory evoked potentials, electroencephalography and neuroimaging data with anamnestic report and toxicological and laboratory data.

Altered Cytokine Endotoxin Responses in Neonatal Encephalopathy Predict MRI Outcomes

Background: Neonatal encephalopathy (NE) is associated with adverse neurodevelopmental outcome and is linked with systemic inflammation. Pro-inflammatory and anti-inflammatory cytokines are known to play a role in the pathology of NE by activating innate immune cells. Methods: Eighty-seven infants were enrolled including 53 infants with NE of whom 52 received therapeutic hypothermia (TH) and 34 term infant healthy controls (TC). Whole blood sampling was performed in the first 4 days of life, and a 14-spot ELISA Multiplex Cytokine Array was carried out on baseline samples or after stimulation with lipopolysaccharide (LPS) as an additional inflammatory stimulus. The cytokine medians were examined for differences between infants with NE and healthy TC; and then short-term outcomes of Sarnat stage, seizures, and MRI brain were examined within the NE group. The potential of LPS stimulation to predict abnormal MRI was explored using receiver operating characteristic (ROC) curves. Results: At baseline, infants with NE had significantly higher levels of erythropoietin (Epo), interleukin (IL)-6, and IL-1ra and significantly lower vascular endothelial growth factor (VEGF) than had controls. All cytokines were increased after LPS stimulation in infants with NE with an excessive Epo and IL-1ra response than in controls. Infants with NE had lower IL-8, IL-2, IL-6, tumor necrosis factor (TNF)-α, granulocyte-macrophage colony-stimulating factor (GM-CSF), VEGF, and interferon (IFN)-γ than controls had following LPS. GM-CSF and IFN-γ, IL-1β, IL-1ra, and VEGF were higher on days 1-2 in NE infants with abnormal neuroimaging. GM-CSF, IFN-γ, and TNF-α levels with LPS stimulation were different upon stimulation between normal and abnormal neuroimaging. TNF-α is the only strong cytokine predictor both pre- and post-LPS stimulation of abnormal brain imaging. Conclusions: Altered cytokine responses are found in infants with NE vs. controls, and more significant differences are unmasked by the additional stimulus of LPS, which potentially improves the predictive power of these cytokines for the detection of abnormal MRIs. Infants with NE undergoing TH demonstrate both trained immunity and tolerance, and understanding these responses will facilitate adjunctive immunomodulatory treatments.

Umbilical artery carbon dioxide decreases the risk for hypoxic-ischaemic encephalopathy

AIM

An accurate biomarker for metabolic acidosis at birth is needed. Our aims were to investigate the link between umbilical artery pCO₂ and the risk for hypoxic-ischaemic encephalopathy (HIE) and to compare false-negative screen results in newborn infants with HIE using three umbilical artery blood gas biomarkers.

METHODS

From a cohort of newborn infants ≥35 weeks born in Ottawa, Canada, between January 2007 and December 2016, we highlighted those with HIE or who died. We compared the umbilical artery pCO₂ for matched pH >mean versus matched pH ≤mean. We compared false-negative rates for three umbilical artery biomarkers-pH <7.0, base deficit ≥16 mmol/L and neonatal eucapnic pH ≤7.14.

RESULTS

This study included 51 286 newborn infants, 51% male and a mean gestational age of 38.9 ± 1.5 weeks. The rate for HIE or death with umbilical artery pCO₂ for matched pH >mean was 22%, compared to 78% for matched pH ≤mean. In 60 HIE or deaths, the false-negative rate for umbilical artery neonatal eucapnic pH ≤7.14 was 8%; compared to 31% for pH <7.00 and 36% for base deficit ≥16 mmol/L.

CONCLUSION

The rate of HIE or death is lower in newborn infants with higher pCO₂ . Using neonatal eucapnic pH decreases the risk of missing newborn infants with HIE.

Troponin T correlates with MRI results in neonatal encephalopathy

AIM

Troponin is a sensitive marker of asphyxia in term infants mirroring the myocardial injury sustained in global hypoxia-ischaemia. In addition, troponin is a sensitive marker of severity of stroke in adults and neonatal encephalopathy (NE). We aimed to examine the relationship between troponin T in infants with perinatal asphyxia and brain injury on MRI and correlate with neurodevelopmental outcome.

METHODS

Serum troponin was sampled in infants requiring resuscitation at birth and/or neonatal encephalopathy in a tertiary referral neonatal centre. Birth history, clinical parameters, neuroimaging and developmental outcome (Bayley Scores of Infant Development [BSID] III) were evaluated.

RESULTS

Infants with perinatal asphyxia (n = 54) had serum troponin T measured and 27 required therapeutic hypothermia. Troponin T levels on days 1 and 2 were predictive of need for TH, development of seizures and grade II/III NE (AUC = 0.7; P-values < .001), troponin T levels on days 1, 2 and 3 were highly significant predictors of mortality (AUC = 0.99, P-values .005). The cut-off values of troponin T for best prediction of mortality were 0.84, 0.63 and 0.58 ng/mL on days 1, 2 and 3, respectively. Troponin T on day 3 of life was predictive of injury in the combined area of basal ganglia/watershed on MRI (AUC 0.70; P-value = .045).

CONCLUSION

Infants with brain injury on neuroimaging following perinatal asphyxia had significantly elevated serum troponin, and troponin also correlated with developmental scores at 2 years. Further studies combining troponin and MRI may assist in the classification of neonatal brain injury to define aetiology, prognosis and response to treatment.

Movement disorders after hypoxic brain injury following cardiac arrest in adults

BACKGROUND AND PURPOSE

Post-hypoxic movement disorders and chronic post-hypoxic myoclonus are rare complications after cardiac arrest in adults. Our study investigates the clinical spectrum, neuroimaging results, therapy and prognosis of these debilitating post-hypoxic sequelae.

METHODS

This retrospective study included 72 patients from the neurological intensive care unit at a university hospital, who were diagnosed with hypoxic-ischaemic encephalopathy after cardiac arrest between January 2007 and September 2018. Clinical records were screened for occurrence of post-hypoxic movement disorders and chronic post-hypoxic myoclonus. Affected patients were further analysed for applied neuroprognostic tests, administered therapy and treatment response, and the outcome of these movement disorders and neurological function.

RESULTS

Nineteen out of 72 screened patients exhibited post-hypoxic motor symptoms. Basal ganglia injury was the most likely neuroanatomical correlate of movement disorders as indicated by T1 hyperintensities and hypometabolism of this region in magnetic resonance imaging and positron emission tomography computed tomography. Levomepromazine and intrathecal baclofen showed first promising and mostly prompt responses to control these post-hypoxic movement disorders and even hyperkinetic storms. In contrast, chronic post-hypoxic myoclonus best responded to co-application of clonazepam, levetiracetam and primidone. Remission rates of post-hypoxic movement disorders and chronic post-hypoxic myoclonus were 58% and 50%, respectively. Affected patients seemed to present a rather good recovery of cognitive functions in contrast to the often more severe physical deficits.

CONCLUSIONS

Post-hypoxic movement disorders associated with pronounced basal ganglia dysfunction might be efficiently controlled by levomepromazine or intrathecal baclofen. Their occurrence might be an indicator for a more unfavourable, but often not devastating, neurological outcome.

School-age outcomes of children without cerebral palsy cooled for neonatal hypoxic-ischaemic encephalopathy in 2008-2010

OBJECTIVE

Since therapeutic hypothermia became standard care for neonatal hypoxic-ischaemic encephalopathy (HIE), even fewer infants die or have disability at 18-month assessment than in the clinical trials. However, longer term follow-up of apparently unimpaired children is lacking. We investigated the cognitive, motor and behavioural performances of survivors without cerebral palsy (CP) cooled for HIE, in comparison with matched non-HIE control children at 6-8 years.

DESIGN

Case-control study.

PARTICIPANTS

29 case children without CP, cooled in 2008-2010 and 20 age-matched, sex-matched and social class-matched term-born controls.

MEASURES

Wechsler Intelligence Scales for Children, Fourth UK Edition, Movement Assessment Battery for Children, Second Edition (MABC-2) and Strengths and Difficulties Questionnaire.

RESULTS

Cases compared with controls had significantly lower mean (SD) full-scale IQ (91 [10.37]vs105[13.41]; mean difference (MD): -13.62, 95% CI -20.53 to -6.71) and total MABC-2 scores (7.9 [3.26]vs10.2[2.86]; MD: -2.12, 95% CI -3.93 to -0.3). Mean differences were significant between cases and controls for verbal comprehension (-8.8, 95% CI -14.25 to -3.34), perceptual reasoning (-13.9, 95% CI-20.78 to -7.09), working memory (-8.2, 95% CI-16.29 to -0.17), processing speed (-11.6, 95% CI-20.69 to -2.47), aiming and catching (-1.6, 95% CI-3.26 to -0.10) and manual dexterity (-2.8, 95% CI-4.64 to -0.85). The case group reported significantly higher median (IQR) total (12 [6.5-13.5] vs 6 [2.25-10], p=0.005) and emotional behavioural difficulties (2 [1-4.5] vs 0.5 [0-2.75], p=0.03) and more case children needed extra support in school (34%vs5%, p=0.02) than the control group.

CONCLUSIONS

School-age children without CP cooled for HIE still have reduced cognitive and motor performance and more emotional difficulties than their peers, strongly supporting the need for school-age assessments.

Maternal risk factors for birth asphyxia in low-resource communities. A systematic review of the literature

Birth asphyxia (BA) affects millions of newborns annually, especially in low-resource communities. Given that much of the attention to this point has focussed upon secondary prevention, we sought to inform the development of primary prevention strategies for BA in resource-limited settings by identifying maternal risk factors. To this end, we systematically reviewed the MEDLINE, PsychInfo, and EMBASE databases, and identified 38 relevant studies. Upon analysis, we found 12 maternal variables associated with BA, and thematically arranged them into 3 categories: sociodemographic factors (age, literacy, gravidity, parity), health care factors (antenatal care, delivery location), and health status (hypertension, pre-eclampsia, eclampsia, anaemia, antepartum haemorrhage, pyrexia). The factors with the greatest, and/or most consistent influence upon likelihood for BA were: young maternal age (<20 years), limited maternal literacy, insufficient antenatal care, non-hospital delivery, maternal hypertension, and anaemia. We hope our review will assist stakeholders guiding the development of BA-related policies and programmes.

Acute LPS sensitization and continuous infusion exacerbates hypoxic brain injury in a piglet model of neonatal encephalopathy

Co-existing infection/inflammation and birth asphyxia potentiate the risk of developing neonatal encephalopathy (NE) and adverse outcome. In a newborn piglet model we assessed the effect of E. coli lipopolysaccharide (LPS) infusion started 4 h prior to and continued for 48 h after hypoxia on brain cell death and systemic haematological changes compared to LPS and hypoxia alone. LPS sensitized hypoxia resulted in an increase in mortality and in brain cell death (TUNEL positive cells) throughout the whole brain, and in the internal capsule, periventricular white matter and sensorimotor cortex. LPS alone did not increase brain cell death at 48 h, despite evidence of neuroinflammation, including the greatest increases in microglial proliferation, reactive astrocytosis and cleavage of caspase-3. LPS exposure caused splenic hypertrophy and platelet count suppression. The combination of LPS and hypoxia resulted in the highest and most sustained systemic white cell count increase. These findings highlight the significant contribution of acute inflammation sensitization prior to an asphyxial insult on NE illness severity.

Levetiracetam optimal dose-finding as first-line treatment for neonatal seizures occurring in the context of hypoxic-ischaemic encephalopathy (LEVNEONAT-1): study protocol of a phase II trial

INTRODUCTION

Therapeutic schedules for treating neonatal seizures remain elusive. First-line treatment with phenobarbital is widely supported but without strong scientific evidence. Levetiracetam (LEV) is an emerging and promising antiepileptic drug (AED). The aim of this phase II trial is to determine the benefits of LEV by applying a strict methodology and to estimate the optimal dose of LEV as a first-line AED to treat seizures in newborns suffering from hypoxic-ischaemic encephalopathy.

METHODS AND ANALYSIS

LEVNEONAT-1 is an open and sequential LEV dose-finding study. The optimal dose is that which is estimated to be associated with a toxicity not exceeding 10% and an efficacy higher than 60%. Efficacy is defined by a seizure burden reduction of 80% after the loading dose. Four increasing dose regimens will be assessed including one loading dose of 30, 40, 50 or 60 mg/kg followed by eight maintenance doses (ie, a quarter of the loading dose) injected every 8 hours. A two-patient cohort will be necessary at each dose level to consider an upper dose level assignment. The maximal sample size expected is 50 participants with a minimum of 24 patients or fewer in the case of a high rate of toxicity. Patients will be recruited in five neonatal intensive care units beginning in October 2017 and continuing for 2 years. In parallel, the LEV pharmacokinetics will be measured five times (ie, 30 min; 4 and 7 hours after the loading dose; 1-3 hours and 12-18 hours after the last maintenance dose).

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the regional ethical committee (2016-R25) and the French Drug Safety Agency (160652A-31). The results will be published in a peer-reviewed journal. The results will also be presented at medical meetings.

TRIAL REGISTRATION NUMBER

NCT02229123; Pre-results.

Untargeted metabolomic analysis and pathway discovery in perinatal asphyxia and hypoxic-ischaemic encephalopathy

Elucidating metabolic effects of hypoxic-ischaemic encephalopathy (HIE) may reveal early biomarkers of injury and new treatment targets. This study uses untargeted metabolomics to examine early metabolic alterations in a carefully defined neonatal population. Infants with perinatal asphyxia who were resuscitated at birth and recovered (PA group), those who developed HIE (HIE group) and healthy controls were all recruited at birth. Metabolomic analysis of cord blood was performed using direct infusion FT-ICR mass spectrometry. For each reproducibly detected metabolic feature, mean fold differences were calculated HIE vs. controls (ΔHIE) and PA vs. controls (ΔPA). Putative metabolite annotations were assigned and pathway analysis was performed. Twenty-nine putatively annotated metabolic features were significantly different in ΔPA after false discovery correction ( q < 0.05), with eight of these also significantly altered in ΔHIE. Altered putative metabolites included; melatonin, leucine, kynurenine and 3-hydroxydodecanoic acid which differentiated between infant groups (ΔPA and ΔHIE); and D-erythrose-phosphate, acetone, 3-oxotetradecanoic acid and methylglutarylcarnitine which differentiated across severity grades of HIE. Pathway analysis revealed ΔHIE was associated with a 50% and 75% perturbation of tryptophan and pyrimidine metabolism, respectively. We have identified perturbed metabolic pathways and potential biomarkers specific to PA and HIE, which measured at birth, may help direct treatment.

Coagulation Profiles Are Associated With Early Clinical Outcomes in Neonatal Encephalopathy

Introduction: Neonatal encephalopathy (NE) is associated with coagulation abnormalities. We aimed to investigate the serial alterations in coagulation profiles in term infants with NE and correlate with their clinical outcomes. This was a prospective cohort study in a tertiary referral, university-affiliated maternity hospital. Neonates exposed to perinatal asphyxia were recruited (n = 82) and 39 received therapeutic hypothermia. Infants had serial coagulation tests including platelets, prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen in the first week of life. The main outcome measures included MRI brain and EEG seizures. Our results show that mortality was predicted on day 1 by decreased Fibrinogen (AUC = 0.95, p = 0.009) and by PT on day 2 with a cutoff of 22 s. An abnormal MRI was predicted by Fibrinogen on day 3 with a cut-off value of 2 g/L. For prediction of grade II/III NE, PT on day 2 of life was strongest with a cut-off value of 14 s. Only elevated APTT levels on day 1 of life were predictive of seizures (AUC = 0.65, p = 0.04). Conclusion: Coagulation parameters are strong predictors of outcomes such as abnormal NE grade, seizures, and mortality.

Neuroprotective exendin-4 enhances hypothermia therapy in a model of hypoxic-ischaemic encephalopathy

Hypoxic-ischaemic encephalopathy remains a global health burden. Despite medical advances and treatment with therapeutic hypothermia, over 50% of cooled infants are not protected and still develop lifelong neurodisabilities, including cerebral palsy. Furthermore, hypothermia is not used in preterm cases or low resource settings. Alternatives or adjunct therapies are urgently needed. Exendin-4 is a drug used to treat type 2 diabetes mellitus that has also demonstrated neuroprotective properties, and is currently being tested in clinical trials for Alzheimer's and Parkinson's diseases. Therefore, we hypothesized a neuroprotective effect for exendin-4 in neonatal neurodisorders, particularly in the treatment of neonatal hypoxic-ischaemic encephalopathy. Initially, we confirmed that the glucagon like peptide 1 receptor (GLP1R) was expressed in the human neonatal brain and in murine neurons at postnatal Day 7 (human equivalent late preterm) and postnatal Day 10 (term). Using a well characterized mouse model of neonatal hypoxic-ischaemic brain injury, we investigated the potential neuroprotective effect of exendin-4 in both postnatal Day 7 and 10 mice. An optimal exendin-4 treatment dosing regimen was identified, where four high doses (0.5 µg/g) starting at 0 h, then at 12 h, 24 h and 36 h after postnatal Day 7 hypoxic-ischaemic insult resulted in significant brain neuroprotection. Furthermore, neuroprotection was sustained even when treatment using exendin-4 was delayed by 2 h post hypoxic-ischaemic brain injury. This protective effect was observed in various histopathological markers: tissue infarction, cell death, astrogliosis, microglial and endothelial activation. Blood glucose levels were not altered by high dose exendin-4 administration when compared to controls. Exendin-4 administration did not result in adverse organ histopathology (haematoxylin and eosin) or inflammation (CD68). Despite initial reduced weight gain, animals restored weight gain following end of treatment. Overall high dose exendin-4 administration was well tolerated. To mimic the clinical scenario, postnatal Day 10 mice underwent exendin-4 and therapeutic hypothermia treatment, either alone or in combination, and brain tissue loss was assessed after 1 week. Exendin-4 treatment resulted in significant neuroprotection alone, and enhanced the cerebroprotective effect of therapeutic hypothermia. In summary, the safety and tolerance of high dose exendin-4 administrations, combined with its neuroprotective effect alone or in conjunction with clinically relevant hypothermia make the repurposing of exendin-4 for the treatment of neonatal hypoxic-ischaemic encephalopathy particularly promising.

The burden of hypoxic-ischaemic encephalopathy in Malaysian neonatal intensive care units

INTRODUCTION

This study aimed to determine the incidence of hypoxic-ischaemic encephalopathy (HIE) and predictors of HIE mortality in Malaysian neonatal intensive care units (NICUs).

METHODS

This was a retrospective study of data from 37 NICUs in the Malaysian National Neonatal Registry in 2012. All newborns with gestational age ≥ 36 weeks, without major congenital malformations and fulfilling the criteria of HIE were included.

RESULTS

There were 285,454 live births in these hospitals. HIE was reported in 919 newborns and 768 of them were inborn, with a HIE incidence of 2.59 per 1,000 live births/hospital (95% confidence interval [CI] 2.03, 3.14). A total of 144 (15.7%) affected newborns died. Logistic regression analysis showed that the significant predictors of death were: chest compression at birth (adjusted odds ratio [OR] 2.27, 95% CI 1.27, 4.05; p = 0.003), being outborn (adjusted OR 2.65, 95% CI 1.36, 5.13; p = 0.004), meconium aspiration syndrome (MAS) (adjusted OR 2.16, 95% CI 1.05, 4.47; p = 0.038), persistent pulmonary hypertension of the newborn (PPHN) (adjusted OR 4.39, 95% CI 1.85, 10.43; p = 0.001), sepsis (adjusted OR 4.46, 95% CI 1.38, 14.40; p = 0.013), pneumothorax (adjusted OR 4.77, 95% CI 1.76, 12.95; p = 0.002) and severe HIE (adjusted OR 42.41, 95% CI 18.55, 96.96; p < 0.0001).

CONCLUSION

The incidence of HIE in Malaysian NICUs was similar to that reported in developed countries. Affected newborns with severe grade of HIE, chest compression at birth, MAS, PPHN, sepsis or pneumothorax, and those who were outborn were more likely to die before discharge.

Parental perceptions of hypothermia treatment for neonatal hypoxic-ischaemic encephalopathy

AIMS

Hypothermia Treatment (HT) is now the standard care for neonatal hypoxic-ischaemic encephalopathy (HIE). We conducted a survey to explore parental perceptions of HT as there is little information about this in the current literature.

METHODS

Postal questionnaire survey included families (n = 51) whose babies received HT at Princess Anne Hospital, Southampton, UK, with 23 questions covering communication, clinical management, follow-up, and care in general. Statistical analysis of descriptive and analytical tests were done using Minitab 16.

RESULTS

The response rate was 60.8%. All parents had concerns amongst which perceptions of pain and distress were described by 41%. Temporary concerns about bonding were common (83.8%), more so in babies transferred from other hospitals (p = .04). Only 61.3% felt they had a good understanding of HT. The need for improvements in the quality (71%) and frequency of communication (48.3%) were also highlighted.

CONCLUSIONS

Parents were worried about pain and distress, bonding and about outcomes after HT. Consistency in communication, regular updates, involvement of parents in decision making, strong support mechanisms and balanced discussions about long term outcomes at an early stage are of high importance to families whose babies undergo HT.