Acute neonatal morbidity and long-term central nervous system sequelae of perinatal asphyxia in term infants

Prediction of outcome of hypoxic-ischemic encephalopathy in newborns undergoing therapeutic hypothermia using heart rate variability

OBJECTIVE

To assess the use of continuous heart rate variability (HRV) as a predictor of brain injury severity in newborns with moderate to severe HIE that undergo therapeutic hypothermia.

STUDY DESIGN

Two cohorts of newborns (n1 = 55, n2 = 41) with moderate to severe hypoxic-ischemic encephalopathy previously treated with therapeutic hypothermia. HRV was characterized by root mean square in the short time scales (RMSS) during therapeutic hypothermia and through completion of rewarming. A logistic regression and Naïve Bayes models were developed to predict the MRI outcome of the infants using RMSS. The encephalopathy grade and gender were used as control variables.

RESULTS

For both cohorts, the predicted outcomes were compared with the observed outcomes. Our algorithms were able to predict the outcomes with an area under the receiver operating characteristic curve of about 0.8.

CONCLUSIONS

HRV assessed by RMSS can predict severity of brain injury in newborns with HIE.

Respiratory Distress Syndrome (RDS) in Newborns with Hypoxic-Ischemic Encephalopathy (HIE)

Respiratory distress syndrome (RDS) and hypoxic-ischemic encephalopathy (HIE) are frequent causes of death and disability in neonates. This study included newborns between January 2021 and July 2022 at the University Clinic for Gynecology and Obstetrics, Skopje. Up to date criteria for HIE/RDS for term and for preterm infants as well for the severity of HIE/RDS were used in a comprehensive analysis of cranial ultrasonography, neurological status, neonatal infections, Apgar score, bradycardia and hypotension, X-ray of the lungs, FiO2, acid-base status, assisted ventilation and use of surfactant. Three groups were created: HIE with RDS (42 babies), HIE without RDS (30 babies) and RDS without HIE in 38 neonates. All newborns with severe (third) degree of HIE died. Intracranial bleeding was found in 35.7% in the first group and 30% in the second group, and in the third group in 53.3%. The need for surfactant in the HIE group with RDS is 59.5%, and in the RDS group without HIE 84.2%. DIC associated with sepsis was found in 13.1-50% in those groups. In newborns with HIE and bradycardia, the probability of having RDS was on average 3.2 times higher than in those without bradycardia. The application of the surfactant significantly improved the pH, pO2, pCO2, BE and chest X-ray in children with RDS. An Apgar score less than 6 at the fifth minute increases the risk of RDS by 3 times. The metabolic acidosis in the first 24 hours increases the risk of death by 23.6 times. The combination of HIE/ RDS significantly worsens the disease outcome. The use of scoring systems improved the early detection of high risk babies and initiation of early treatment increased the chances for survival without disabilities.

Myocardial Work for Dynamic Monitoring of Myocardial Injury in Neonatal Asphyxia

To assess the value of parameters of myocardial work for dynamic monitoring of myocardial injury after neonatal asphyxia. Fifty-three neonates with asphyxia admitted within 24 h after delivery were divided into a mild asphyxia group (n = 40) and severe asphyxia group (n = 13). Echocardiography was performed within 24 h post-birth, within 72 h post-birth (48 h after first echo), and during recovery. The left ventricular ejection fraction on M-mode echocardiography and by Simpson's biplane method (LVEF and Bi-EF, respectively), stroke volume (SV), cardiac output (CO), cardiac index (CI), global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), and other parameters were measured. Echocardiographic indicators were compared between groups and over time. GWI was significantly increased at 72 h in the mild asphyxia group (P < 0.05) but showed no significant change over time in the severe asphyxia group (P > 0.05). While GCW increased significantly over time in both groups (P < 0.05), it increased earlier in the mild asphyxia group. Time and grouping factors had independent effects on GWI and GCW (P > 0.05). The characteristics of differences in GWI and GCW between the two groups were different from those for LVEF, Bi-EF, SV, CO, CI, and GLS and their change characteristics with improvement from treatment. GWI and GCW changed significantly during recovery from neonatal asphyxia, and their change characteristics differed between mild and severe asphyxia cases. Myocardial work parameters can be used as valuable supplements to traditional indicators of left ventricular function to dynamically monitor the recovery from myocardial injury after neonatal asphyxia.

Remote Monitoring for Seizures During Therapeutic Hypothermia in Neonates With Hypoxic-Ischemic Encephalopathy

Importance

Neonates with hypoxic-ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH) frequently experience seizures, which are associated with adverse outcomes. Efforts to rapidly identify seizures and reduce seizure burden may positively change neurologic and neurodevelopmental outcomes.

Objective

To describe the onset, treatment, and evolution of seizures in a large cohort of newborns with HIE during TH assisted by a telehealth model and remote neuromonitoring approach.

Design, Setting, and Participants

This was a prospective, observational, multicenter cohort study performed between July 2017 and December 2021 in 32 hospitals in Brazil. Participants were newborns with HIE meeting eligibility criteria and receiving TH. Data were analyzed from November 2022 to April 2023.

Exposure

Infants with HIE receiving TH were remotely monitored with 3-channel amplitude-integrated electroencephalography (aEEG) including raw tracing and video imaging, and bedside clinicians received assistance from trained neonatologists and neurologists.

Main Outcomes and Measures

Data on modified Sarnat examination, presence, timing and seizure type, aEEG background activity, sleep-wake cycling, and antiepileptic drugs used were collected. Descriptive statistical analysis was used with independent t test, χ2, Mann-Whitney test, and post hoc analyses applied for associations.

Results

A total of 872 cooled newborns were enrolled; the median (IQR) gestational age was 39 (38-40) weeks, 518 (59.4%) were male, and 59 (6.8%) were classified as having mild encephalopathy by modified Sarnat examination, 504 (57.8%) as moderate, and 180 (20.6%) as severe. Electrographic seizures were identified in 296 newborns (33.9%), being only electrographic in 213 (71.9%) and clinical followed by electroclinical uncoupling in 50 (16.9%). Early abnormal background activity had a significant association with seizures. Infants with flat trace had the highest rate of seizures (58 infants [68.2%]) and the greatest association with the incidence of seizures (odds ratio [OR], 12.90; 95% CI, 7.57-22.22) compared with continuous normal voltage. The absence of sleep-wake cycling was also associated with a higher occurrence of seizures (OR, 2.22; 95% CI, 1.67-2.96). Seizure onset was most frequent between 6 and 24 hours of life (181 infants [61.1%]); however, seizure occurred in 34 infants (11.5%) during rewarming. A single antiepileptic drug controlled seizures in 192 infants (64.9%). The first line antiepileptic drug was phenobarbital in 294 (99.3%).

Conclusions and Relevance

In this cohort study of newborns with HIE treated with TH, electrographic seizure activity occurred in 296 infants (33.9%) and was predominantly electrographic. Seizure control was obtained with a single antiepileptic drug in 192 infants (64.9%). These findings suggest neonatal neurocritical care can be delivered at remote limited resource hospitals due to innovations in technology and telehealth.

FAM3A Ameliorates Brain Impairment Induced by Hypoxia-Ischemia in Neonatal Rat

Hypoxia-ischemia (HI) during crucial periods of brain formation can lead to changes in brain morphology, propagation of neuronal stimuli, and permanent neurodevelopmental impairment, which can have profound effects on cognitive function later in life. FAM3A, a subgroup of family with sequence similarity 3 (FAM3) gene family, is ubiquitously expressed in almost all cells. Overexpression of FAM3A has been evidenced to reduce hyperglycemia via the PI3K/Akt signaling pathway and protect mitochondrial function in neuronal HT22 cells. This study aims to evaluate the protective role of FAM3A in HI-induced brain impairment. Experimentally, maternal rats underwent uterine artery bilateral ligation to induce neonatal HI on day 14 of gestation. At 6 weeks of age, cognitive development assessments including NSS, wire grip, and water maze were carried out. The animals were then sacrificed to assess cerebral mitochondrial function as well as levels of FAM3A, TNF-α and IFN-γ. Results suggest that HI significantly reduced FAM3A expression in rat brain tissues, and that overexpression of FAM3A through lentiviral transduction effectively improved cognitive and motor functions in HI rats as reflected by improved NSS evaluation, cerebral water content, limb strength, as well as spatial learning and memory. At the molecular level, overexpression of FAM3A was able to promote ATP production, balance mitochondrial membrane potential, and reduce levels of pro-inflammatory cytokines TNF-α and IFN-γ. We conclude that FAM3A overexpression may have a protective effect on neuron morphology, cerebral mitochondrial as well as cognitive function. Created with Biorender.com.

Multi-layer perceptron classification & quantification of neuronal survival in hypoxic-ischemic brain image slices using a novel gradient direction, grey level co-occurrence matrix image training

Hypoxic ischemic encephalopathy (HIE) is a major global cause of neonatal death and lifelong disability. Large animal translational studies of hypoxic ischemic brain injury, such as those conducted in fetal sheep, have and continue to play a key role in furthering our understanding of the cellular and molecular mechanisms of injury and developing new treatment strategies for clinical translation. At present, the quantification of neurons in histological images consists of slow, manually intensive morphological assessment, requiring many repeats by an expert, which can prove to be time-consuming and prone to human error. Hence, there is an urgent need to automate the neuron classification and quantification process. In this article, we present a 'Gradient Direction, Grey level Co-occurrence Matrix' (GD-GLCM) image training method which outperforms and simplifies the standard training methodology using texture analysis to cell-classification. This is achieved by determining the Grey level Co-occurrence Matrix of the gradient direction of a cell image followed by direct passing to a classifier in the form of a Multilayer Perceptron (MLP). Hence, avoiding all texture feature computation steps. The proposed MLP is trained on both healthy and dying neurons that are manually identified by an expert and validated on unseen hypoxic-ischemic brain slice images from the fetal sheep in utero model. We compared the performance of our classifier using the gradient magnitude dataset as well as the gradient direction dataset. We also compare the performance of a perceptron, a 1-layer MLP, and a 2-layer MLP to each other. We demonstrate here a way of accurately identifying both healthy and dying cortical neurons obtained from brain slice images of the fetal sheep model under global hypoxia to high precision by identifying the most minimised MLP architecture, minimised input space (GLCM size) and minimised training data (GLCM representations) to achieve the highest performance over the standard methodology.

Variations in practices and outcomes of neonates with hypoxic ischemic encephalopathy treated with therapeutic hypothermia across tertiary NICUs in Canada

OBJECTIVE

To characterize variations in practices and outcomes for neonates with hypoxic-ischemic encephalopathy (HIE) treated with therapeutic hypothermia (TH) across Canadian tertiary Neonatal Intensive Care Units (NICUs).

STUDY DESIGN

Retrospective study of neonates admitted for HIE and treated with TH in 24 tertiary NICUs from the Canadian Neonatal Network, 2010-2020. The two primary outcomes of mortality before discharge and MRI-detected brain injury were compared across NICUs using adjusted standardized ratios (SR) with 95% CI.

RESULTS

Of the 3261 neonates that received TH, 367 (11%) died and 1033 (37%) of the 2822 with MRI results had brain injury. Overall, rates varied significantly across NICUs for mortality (range 5-17%) and brain injury (range 28-51%). Significant variations in use of inotropes, inhaled nitric oxide, blood products, and feeding during TH were identified (p values < 0.01).

CONCLUSION

Significant variations exist in practices and outcomes of HIE neonates treated with hypothermia across Canada.

Pathophysiology of Perinatal Asphyxia in Humans and Animal Models

Perinatal asphyxia is caused by lack of oxygen delivery (hypoxia) to end organs due to an hypoxemic or ischemic insult occurring in temporal proximity to labor (peripartum) or delivery (intrapartum). Hypoxic–ischemic encephalopathy is the clinical manifestation of hypoxic injury to the brain and is usually graded as mild, moderate, or severe. The search for useful biomarkers to precisely predict the severity of lesions in perinatal asphyxia and hypoxic–ischemic encephalopathy (HIE) is a field of increasing interest. As pathophysiology is not fully comprehended, the gold standard for treatment remains an active area of research. Hypothermia has proven to be an effective neuroprotective strategy and has been implemented in clinical routine. Current studies are exploring various add-on therapies, including erythropoietin, xenon, topiramate, melatonin, and stem cells. This review aims to perform an updated integration of the pathophysiological processes after perinatal asphyxia in humans and animal models to allow us to answer some questions and provide an interim update on progress in this field.

The Effects of In Utero Fetal Hypoxia and Creatine Treatment on Mitochondrial Function in the Late Gestation Fetal Sheep Brain

Near-term acute hypoxia in utero can result in significant fetal brain injury, with some brain regions more vulnerable than others. As mitochondrial dysfunction is an underlying feature of the injury cascade following hypoxia, this study is aimed at characterizing mitochondrial function at a region-specific level in the near-term fetal brain after a period of acute hypoxia. We hypothesized that regional differences in mitochondrial function would be evident, and that prophylactic creatine treatment would mitigate mitochondrial dysfunction following hypoxia; thereby reducing fetal brain injury. Pregnant Border-Leicester/Merino ewes with singleton fetuses were surgically instrumented at 118 days of gestation (dGa; term is ~145 dGA). A continuous infusion of either creatine (n = 15; 6 mg/kg/h) or isovolumetric saline (n = 16; 1.5 ml/kg/h) was administered to the fetuses from 121 dGa. After 10 days of infusion, a subset of fetuses (8 saline-, 7 creatine-treated) were subjected to 10 minutes of umbilical cord occlusion (UCO) to induce a mild global fetal hypoxia. At 72 hours after UCO, the fetal brain was collected for high-resolution mitochondrial respirometry and molecular and histological analyses. The results show that the transient UCO-induced acute hypoxia impaired mitochondrial function in the hippocampus and the periventricular white matter and increased the incidence of cell death in the hippocampus. Creatine treatment did not rectify the changes in mitochondrial respiration associated with hypoxia, but there was a negative relationship between cell death and creatine content following treatment. Irrespective of UCO, creatine increased the proportion of cytochrome c bound to the inner mitochondrial membrane, upregulated the mRNA expression of the antiapoptotic gene Bcl2, and of PCG1-α, a driver of mitogenesis, in the hippocampus. We conclude that creatine treatment prior to brief, acute hypoxia does not fundamentally modify mitochondrial respiratory function, but may improve mitochondrial structural integrity and potentially increase mitogenesis and activity of antiapoptotic pathways.

Protecting brains and saving futures guidelines: A prospective, multicenter, and observational study on the use of telemedicine for neonatal neurocritical care in Brazil

Background

Management of high-risk newborns should involve the use of standardized protocols and training, continuous and specialized brain monitoring with electroencephalography (EEG), amplitude integrated EEG, Near Infrared Spectroscopy, and neuroimaging. Brazil is a large country with disparities in health care assessment and some neonatal intensive care units (NICUs) are not well structured with trained personnel able to provide adequate neurocritical care. To reduce this existing gap, an advanced telemedicine model of neurocritical care called Protecting Brains and Saving Futures (PBSF) Guidelines was developed and implemented in a group of Brazilian NICUs.

Methods

A prospective, multicenter, and observational study will be conducted in all 20 Brazilian NICUs using the PBSF Guidelines as standard-of-care. All infants treated accordingly to the guidelines during Dec 2021 to Nov 2024 will be eligible. Ethical approval was obtained from participating centers. The primary objective is to describe adherence to the PBSF Guidelines and clinical outcomes, by center and over a 3-year period. Adherence will be measured by quantification of neuromonitoring, neuroimaging exams, sub-specialties consultation, and clinical case discussions and videoconference meetings. Clinical outcomes of interest are detection of seizures during hospitalization, use of anticonvulsants, inotropes, and fluid resuscitation, death before hospital discharge, length of hospital stay, and referral of patients to specialized follow-up.

Discussion

The study will provide evaluation of PBSF Guidelines adherence and its impact on clinical outcomes. Thus, data from this large prospective, multicenter, and observational study will help determine whether neonatal neurocritical care via telemedicine can be effective. Ultimately, it may offer the necessary framework for larger scale implementation and development of research projects using remote neuromonitoring.

Trial registration

NCT03786497, Registered 26 December 2018, https://www.clinicaltrials.gov/ct2/show/NCT03786497?term=protecting+brains+and+saving+futures&draw=2&rank=1.

Serial plasma biomarkers of brain injury in infants with neonatal encephalopathy treated with therapeutic hypothermia

BACKGROUND

Neonatal encephalopathy (NE) is a major cause of long-term neurodevelopmental disability in neonates. We evaluated the ability of serially measured biomarkers of brain injury to predict adverse neurological outcomes in this population.

METHODS

Circulating brain injury biomarkers including BDNF, IL-6, IL-8, IL-10, VEGF, Tau, GFAP, and NRGN were measured at 0, 12, 24, 48, 72, and 96 h of cooling from 103 infants with NE undergoing TH. The biomarkers' individual and combinative ability to predict death or severe brain injury and adverse neurodevelopmental outcomes beyond 1 year of age was assessed.

RESULTS

Early measurements of inflammatory cytokines IL-6, 8, and 10 within 24 HOL (AUC = 0.826) and late measurements of Tau from 72 to 96 HOL (AUC = 0.883, OR 4.37) were accurate in predicting severe brain injury seen on MRI. Late measurements of Tau were predictive of adverse neurodevelopmental outcomes (AUC = 0.81, OR 2.59).

CONCLUSIONS

Tau was consistently a predictive marker for brain injury in neonates with NE. However, in the first 24 HOL, IL-6, 8, and 10 in combination were most predictive of death or severe brain injury. The results of this study support the use of a serial biomarker panel to assess brain injury over the time course of disease in NE.

IMPACT

While recent studies have evaluated candidate brain injury biomarkers, no biomarker is in current clinical use. This study supports the use of a serial biomarker panel for ongoing assessment of brain injury neonates with NE. In combination, IL6, IL8, and IL10 in the first 24 h of cooling were more predictive of brain injury by MRI than each cytokine alone. Individually, Tau was overall most consistently predictive of adverse neurological outcomes, particularly when measured at or after rewarming.

Treatment device for neonatal birth asphyxia related Hypoxic Ischemic Encephalopathy

Background

Birth asphyxia is a leading cause of neonatal brain injury, morbidity, and mortality globally. It leads to a multi-organ dysfunction in the neonate and to a neurological dysfunction called Hypoxic Ischemic Encephalopathy (HIE). Cooling therapy is commonly used to slow or stop the damaging effects of birth asphyxia. However, most of the cooling devices used in the healthcare facility do not have a rewarming functionality after cooling therapy. A separate rewarming device, usually a radiant warmer or incubator is used to rewarm the infant after therapy, causing additional burden to the healthcare system and infant families. The objective of this project was, therefore, to design and develop a cost-effective and efficient total body cooling and rewarming device.

Methods

Our design includes two water reservoirs that operate by pumping cold and warm sterile water to a mattress. After decreasing the infant’s core body temperature to 33.5 °C, the system is designed to maintain it for 72 h. Feedback for temperature regulation is provided by the rectal and mattress temperature sensors. Once the cooling therapy is completed, the system again rewarms the water inside the mattress and gradually increases the neonate temperature to 36.5–37 °C. The water temperature sensors’ effectiveness was evaluated by adding 1000 ml of water to the reservoir and cooling and warming to the required level of temperature using Peltier. Then a digital thermometer was used as a gold standard to compare with the sensor’s readings. This was performed for five iterations.

Results

The prototype was built and gone through different tests and iterations. The proposed device was tested for accuracy, cost-effectiveness and easy to use. Ninety-three point two percent accuracy has been achieved for temperature sensor measurement, and the prototype was built only with a component cost of less than 200 USD. This is excluding design, manufacturing, and other costs.

Conclusion

A device that can monitor and regulate the neonate core body temperature at the neuroprotective range is designed and developed. This is achieved by continuous monitoring and regulation of the water reservoirs, mattress, and rectal temperatures. The device also allows continuous monitoring of the infant’s body temperature, mattress temperature, reservoir temperature, and pulse rate. The proposed device has the potential to play a significant role in reducing neonatal brain injury and death due to HIE, especially in low resource settings, where the expertise and the means are scarce.

Long-Term Outcome after Asphyxia and Therapeutic Hypothermia in Late Preterm Infants: A Pilot Study

Therapeutic hypothermia (THT) is the recommended treatment for neuroprotection in (near) term newborns that experience perinatal asphyxia with hypoxic-ischemic encephalopathy. The benefit of THT in preterm newborns is unknown. This pilot study aims to investigate long-term outcomes of late preterm asphyctic infants with and without THT compared to term infants. The single-center, retrospective analysis examined medical charts of infants with perinatal asphyxia born between 2008 and 2015. Long-term outcome was assessed using the Bayley Scales of Infant Development 2 at the age of (corrected) 24 months. Term (n = 31) and preterm (n = 8) infants with THT showed no differences regarding their long-term outcomes of psychomotor development (Psychomotor Developmental Index 101 ± 16 vs. 105 ± 11, p = 0.570), whereas preterm infants had a better mental outcome (Mental Developmental Index 105 ± 13 vs. 93 ± 18, p = 0.048). Preterm infants with and without (n = 69) THT showed a similar mental and psychomotor development (Mental Developmental Index 105 ± 13 vs. 96 ± 20, p = 0.527; Psychomotor Developmental Index 105 ± 11 vs. 105 ± 15, p = 0.927). The study highlights the importance of studying THT in asphyctic preterm infants. However, this study shows limitations and should not be used as a basis for decision-making in the clinical context. Results of a multicenter trial of THT for preterm infants (ID No.: CN-01540535) have to be awaited.

The Term Newborn: Evaluation for Hypoxic-Ischemic Encephalopathy

Neonatal encephalopathy due to perinatal hypoxia-ischemia (hypoxic-ischemic encephalopathy [HIE]) occurs at a rate of 1 to 3 per 1000 live births. Therapeutic hypothermia is the standard of care and the only currently available therapy to reduce the risk of death or disability in newborns with moderate to severe HIE. Hypothermia therapy needs to be initiated within 6 hours after birth in order to provide the best chance for neuroprotection. All pediatricians and delivery room attendants should be trained to recognize encephalopathy and understand the eligibility criteria for treatment. The modified Sarnat examination is the most frequently used tool to assess the degree of encephalopathy and has six categories, each of which can have mild, moderate, severe abnormalities. Apart from historical and biochemical criteria, a neonate must have 3 of 6 categories scored in the moderate or severe range in order to qualify for hypothermia as was done in the randomized trials. Whether an infant qualifies or there is concern that an infant might have HIE, transfer to a center that can perform treatment should be initiated immediately. Hypothermia significantly reduces the risk of death or moderate to severe impairments at 2 years and at school age. On average, only 7 neonates need to be treated for one neonate to benefit. Although easy in concept, implementation of hypothermia does require expertise and should be carried out under the guidance of a neonatologist. If infants are passively cooled prior to transport, core temperature needs to be closely monitored with a target of 33.5°C ± 0.5°C. Maintenance of homeostasis is important in order to prevent conditions that may result in additional brain injury. Seizures are common in neonates with HIE, but electrographic seizures are rare in the first few hours after birth if the insult occurred during labor and delivery. Prophylactic antiepileptic drugs should not be administered. Brain monitoring in the form of electroencephalogram (EEG) and or amplitude-integrated EEG should be implemented as soon as possible to help with prognosis and to accurately diagnose seizures.

Altered distributions and functions of natural killer T cells and γδ T cells in neonates with neonatal encephalopathy, in school-age children at follow-up, and in children with cerebral palsy

We enumerated conventional and innate lymphocyte populations in neonates with neonatal encephalopathy (NE), school-age children post-NE, children with cerebral palsy and age-matched controls. Using flow cytometry, we demonstrate alterations in circulating T, B and natural killer cell numbers. Invariant natural killer T cell and Vδ2⁺ γδ T cell numbers and frequencies were strikingly higher in neonates with NE, children post-NE and children with cerebral palsy compared to age-matched controls, whereas mucosal-associated invariant T cells and Vδ1 T cells were depleted from children with cerebral palsy. Upon stimulation ex vivo, T cells, natural killer cells and Vδ2 T cells from neonates with NE more readily produced inflammatory cytokines than their counterparts from healthy neonates, suggesting that they were previously primed or activated. Thus, innate and conventional lymphocytes are numerically and functionally altered in neonates with NE and these changes may persist into school-age.

Effect of Therapeutic Hypothermia on the Outcome in Term Neonates with Hypoxic Ischemic Encephalopathy-A Randomized Controlled Trial

OBJECTIVE

To assess the effect of therapeutic hypothermia on the outcome in term neonates with hypoxic ischemic encephalopathy (HIE).

METHODS

A randomized controlled trial was conducted in a tertiary care teaching hospital in south India. Term infants with moderate to severe HIE were randomized to be treated with normothermia or hypothermia. Mortality, neurological abnormality or normal outcome was recorded at hospital discharge or 28 days of age, whichever was earlier, and at 18 months of age.

RESULTS

The baseline maternal and neonatal characteristics in the two groups were similar. The 78 infants in the hypothermia group had more normal survivors at discharge (38%) than the 84 infants in the normothermia group (30%), ratio 1.29 (95% confidence interval 0.84-1.99), and at 18 months of age (65% vs. 42%), ratio 1.54 (1.13-2.10). When these results were combined with those of a previous randomized trial in the same neonatal unit, there were significantly more normal survivors with hypothermia compared to normothermia at discharge, ratio 1.49 (1.18-1.88) and at 6-18 months of age, ratio 1.37 (1.17-1.60).

CONCLUSION

In term infants with HIE, therapeutic hypothermia reduced mortality and neurological abnormalities, and resulted in more normal survivors.

LAY SUMMARY

Babies who do not breathe immediately after they are born are likely to die or have brain damage. Previous studies have suggested that cooling these babies after birth might reduce the number who die or have brain damage. In this resource-limited setting, babies who were cooled were less likely to die or survive with brain damage.

Multi-Organ Dysfunction in Cerebral Palsy

Cerebral Palsy (CP) describes a heterogenous group of non-progressive disorders of posture or movement, causing activity limitation, due to a lesion in the developing brain. CP is an umbrella term for a heterogenous condition and is, therefore, descriptive rather than a diagnosis. Each case requires detailed consideration of etiology. Our understanding of the underlying cause of CP has developed significantly, with areas such as inflammation, epigenetics and genetic susceptibility to subsequent insults providing new insights. Alongside this, there has been increasing recognition of the multi-organ dysfunction (MOD) associated with CP, in particular in children with higher levels of motor impairment. Therefore, CP should not be seen as an unchanging disorder caused by a solitary insult but rather, as a condition which evolves over time. Assessment of multi-organ function may help to prevent complications in later childhood or adulthood. It may also contribute to an improved understanding of the etiology and thus may have an implication in prevention, interventional methods and therapies. MOD in CP has not yet been quantified and a scoring system may prove useful in allowing advanced clinical planning and follow-up of children with CP. Additionally, several biomarkers hold promise in assisting with long-term monitoring. Clinicians should be aware of the multi-system complications that are associated with CP and which may present significant diagnostic challenges given that many children with CP communicate non-verbally. A step-wise, logical, multi-system approach is required to ensure that the best care is provided to these children. This review summarizes multi-organ dysfunction in children with CP whilst highlighting emerging research and gaps in our knowledge. We identify some potential organ-specific biomarkers which may prove useful in developing guidelines for follow-up and management of these children throughout their lifespan.

Exploratory Assessment of the Relationship Between Hemoglobin Volume Phase Index, Magnetic Resonance Imaging, and Functional Outcome in Neonates with Hypoxic-Ischemic Encephalopathy

BACKGROUND/OBJECTIVE

Near-infrared spectroscopy (NIRS)-based measures of cerebral autoregulation (CAR) can potentially identify neonates with hypoxic-ischemic encephalopathy (HIE) who are at greatest risk of irreversible brain injury. However, modest predictive abilities have precluded previously described metrics from entering clinical care. We previously validated a novel autoregulation metric in a piglet model of induced hypotension called the hemoglobin volume phase index (HVP). The objective of this study was to evaluate the clinical ability of the HVP to predict adverse outcomes neonates with HIE.

METHODS

This is a prospective study of neonates with HIE who underwent therapeutic hypothermia (TH) at a level 4 neonatal intensive care unit (NICU). Continuous cerebral NIRS and mean arterial blood pressure (MAP) from indwelling arterial catheters were measured during TH and through rewarming. Multivariate autoregressive process was used to calculate the coherence between MAP and the sum total of the oxy- and deoxygenated Hb densities (HbT), a surrogate measure of cerebral blood volume (CBV). The HVP was calculated as the cosine-transformed phase shift at the frequency of maximal MAP-HbT coherence. Brain injury was assessed by neonatal magnetic resonance imaging (MRI), and developmental outcomes were assessed by the Bayley Scales of Infant Development (BSID-III) at 15-30 months. The ability of the HVP to predict (a) death or severe brain injury by MRI and (b) death or significant developmental delay was assessed using logistic regression analyses.

RESULTS

In total, 50 neonates with moderate or severe HIE were monitored. Median HVP was higher, representing more dysfunctional autoregulation, in infants who had adverse outcomes. After adjusting for sex and encephalopathy grade at presentation, HVP at 21-24 and 24-27 h of life predicted death or brain injury by MRI (21-24 h: OR 8.8, p = 0.037; 24-27 h: OR 31, p = 0.011) and death or developmental delay at 15-30 months (21-24 h: OR 11.8, p = 0.05; 24-27 h: OR 15, p = 0.035).

CONCLUSIONS

Based on this pilot study of neonates with HIE, HVP merits further study as an indicator of death or severe brain injury on neonatal MRI and neurodevelopmental delay in early childhood. Larger studies are warranted for further clinical validation of the HVP to evaluate cerebral autoregulation following HIE.

Deep hypothermia prevents striatal alterations produced by perinatal asphyxia: Implications for the prevention of dyskinesia and psychosis

GABAergic medium spiny neurons are the main neuronal population in the striatum. Calbindin is preferentially expressed in medium spiny neurons involved in the indirect pathway. The aim of the present work is to analyze the effect of perinatal asphyxia on different subpopulations of GABAergic neurons in the striatum and to assess the outcome of deep therapeutic hypothermia. The uterus of pregnant rats was removed by cesarean section and the fetuses were exposed to hypoxia by immersion in water (19 min) at 37°C (perinatal asphyxia). The hypothermic group was exposed to 10°C during 30 min after perinatal asphyxia. The rats were euthanized at the age of one month (adolescent/adult rats), their brains were dissected out and coronal sections were immunolabeled for calbindin, calretinin, NeuN, and reelin. Reelin+ cells showed no staining in the striatum besides subventricular zone. The perinatal asphyxia (PA) group showed a significant decrease in calbindin neurons and a paradoxical increase in neurons estimated by NeuN staining. Moreover, calretinin+ cells, a specific subpopulation of GABAergic neurons, showed an increase caused by PA. Deep hypothermia reversed most of these alterations probably by protecting calbindin neurons. Similarly, there was a reduction of the diameter of the anterior commissure produced by the asphyxia that was prevented by hypothermic treatment.

Maternal alcoholism and neonatal hypoxia-ischemia: Neuroprotection by stilbenoid polyphenols

The impact of maternal nutrition on neurodevelopment and neonatal neuroprotection is a research topic with increasing interest. Maternal diet can also have deleterious effects on fetal brain development. Fetal exposure to alcohol is responsible for poor neonatal global development, and may increase brain vulnerability to hypoxic-ischemic encephalopathy, one of the major causes of acute mortality and chronic neurological disability in newborns. Despite frequent prevention campaigns, about 10% of women in the general population drinks alcohol during pregnancy and breastfeeding. This study was inspired by this alarming fact. Its aim was to evaluate the beneficial effects of maternal supplementation with two polyphenols during pregnancy and breastfeeding, on hypoxic-ischemic neonate rat brain damages, sensorimotor and cognitive impairments, in a context of moderate maternal alcoholism. Both stilbenoid polyphenols, trans-resveratrol (RSV - 0.15 mg/kg/day), and its hydroxylated analog, trans-piceatannol (PIC - 0.15 mg/kg/day), were administered in the drinking water, containing or not alcohol (0.5 g/kg/day). In a 7-day post-natal rat model of hypoxia-ischemia (HI), our data showed that moderate maternal alcoholism does not increase brain lesion volumes measured by MRI but leads to higher motor impairments. RSV supplementation could not reverse the deleterious effects of HI coupled with maternal alcoholism. However, PIC supplementation led to a recovery of all sensorimotor and cognitive functions. This neuroprotection was obtained with a dose of PIC corresponding to the consumption of a single passion fruit per day for a pregnant woman.

Monitoring the effectiveness of hypothermia in perinatal asphyxia infants by urinary S100B levels

Background Perinatal asphyxia is a major cause of mortality and morbidity in neonates: The aim of the present study was to investigate, by means of longitudinal assessment of urinary S100B, the effectiveness of hypothermia, in infants complicated by perinatal asphyxia and hypoxic-ischemic encephalopathy. Methods We performed a retrospective case-control study in 108 asphyxiated infants, admitted to nine tertiary departments for neonatal intensive care from January 2004 to July 2017, of whom 54 underwent hypothermia treatment and 54 did not. The concentrations of S100B protein in urine were measured using an immunoluminometric assay at first urination and 4, 8, 12, 16, 20, 24, 48, 72, 96, 108 and 120 h after birth. The results were correlated with the achievement of S100B levels within normal ranges at 72 h from hypothermia treatment. Routine laboratory parameters, longitudinal cerebral function monitoring, cerebral ultrasound and neurologic patterns were assessed according to standard protocols. Results Higher S100B concentrations were found in hypothermia-treated infants in both moderate (up to 12 h) and severe (up to 24 h) hypoxic-ischemic encephalopathy. S100B levels returned to normal ranges starting from 20 h of hypothermia treatment in moderate and from 36 h in severe hypoxic-ischemic encephalopathy. Conclusions The present results offer additional support to the usefulness of longitudinal neuro-biomarkers monitoring in asphyxiated infants treated by hypothermia. The pattern of S100B concentrations during hypothermia supports the need for further investigations aimed at reconsidering the time-window for patient recruitment and treatment, and the optimal duration of the cooling and rewarming phases of the hypothermia procedure.

Proteasome Biology Is Compromised in White Matter After Asphyxic Cardiac Arrest in Neonatal Piglets

Background

Neurological deficits in hypoxic‐ischemic encephalopathy, even with therapeutic hypothermia, are partially attributed to white matter injury. We theorized that proteasome insufficiency contributes to white matter injury.

Methods and Results

Neonatal piglets received hypoxia‐ischemia (HI) or sham procedure with normothermia, hypothermia, or hypothermia+rewarming. Some received a proteasome activator drug (oleuropein) or white matter–targeted, virus‐mediated proteasome knockdown. We measured myelin oligodendrocyte glycoprotein, proteasome subunit 20S (P20S), proteasome activity, and carbonylated and ubiquitinated protein levels in white matter and cerebral cortex. HI reduced myelin oligodendrocyte glycoprotein levels regardless of temperature, and myelin oligodendrocyte glycoprotein loss was associated with increased ubiquitinated and carbonylated protein levels. Ubiquitinated and carbonyl‐damaged proteins increased in white matter 29 hours after HI during hypothermia to exceed levels at 6 to 20 hours. In cortex, ubiquitinated proteins decreased. Ubiquitinated and carbonylated protein accumulation coincided with lower P20S levels in white matter; P20S levels also decreased in cerebral cortex. However, proteasome activity in white matter lagged behind that in cortex 29 hours after HI during hypothermia. Systemic oleuropein enhanced white matter P20S and protected the myelin, whereas proteasome knockdown exacerbated myelin oligodendrocyte glycoprotein loss and ubiquitinated protein accumulation after HI. At the cellular level, temperature and HI interactively affected macroglial P20S enrichment in subcortical white matter. Rewarming alone increased macroglial P20S immunoreactivity, but this increase was blocked by HI.

Conclusions

Oxidized and ubiquitinated proteins accumulate with HI‐induced white matter injury. Proteasome insufficiency may drive this injury. Hypothermia did not prevent myelin damage, protect the proteasome, or preserve oxidized and ubiquitinated protein clearance after HI.

Myocardial dysfunction as a predictor of the severity and mortality of hypoxic ischaemic encephalopathy in severe perinatal asphyxia: a case-control study

Background: In perinatal asphyxia, hypoxia often leads to myocardial ischaemia. Few studies have assessed the degree of myocardial dysfunction in severely asphyxiated term neonates. Aim: To assess the extent of myocardial damage in newborns with severe perinatal asphyxia. Methods: A case-control study was conducted in asphyxiated newborns with hypoxic ischaemic encephalopathy (HIE) and in controls who were term non-asphyxiated newborns. Total (T) creatinine kinase (CK), CK-MB, troponin-T and 12-lead electrocardiography (ECG) and echocardiography were performed in both groups within 24-48 h after birth. The proportions of asphyxiated neonates with myocardial dysfunction and its relationship between severity of HIE and immediate outcome was compared. Results: Five of 23 asphyxiated neonates developed stage I, 10 stage II and eight stage III HIE. Serum levels of CK-T and CK-MB were raised in all 23 cases and troponin-T was raised in 13 (56.5%) HIE cases. ECG was abnormal in all cases and echocardiography in three (13%). Left ventricular ejection fraction (LVEF) and right ventricular ejection fraction (RVEF) were significantly decreased in all asphyxiated neonates. Eight (35%) patients died. Enzyme levels were higher and ECG and echocardiography abnormalities were common in infants with more severe HIE (p <0.05). Mean serum levels of CK-T and MB (p <0.001) and troponin-T (p =0.002) were higher in non-survivors. Mean LVEF and RVEF values were higher in survivors (p <0.001). All the controls had normal enzyme levels and echocardiography. ECG was abnormal in one control. Conclusion: Cardiac enzymes, ECG and echocardiography changes were associated with increasing severity of HIE and mortality.

Placental clearance/synthesis of neurobiomarkers GFAP and UCH-L1 in healthy term neonates and those with moderate-severe neonatal encephalopathy

BACKGROUND

Fetal concentrations of GFAP and UCH-L1 are elevated in umbilical arterial (UmA) blood of neonates with birth asphyxia plus neonatal encephalopathy (NE), but their source and role of placental clearance/synthesis is unknown.

METHODS

Prospective cohort study of term neonates to (a) determine UmA and venous (UmV) blood concentrations of GFAP and UCH-L1 in term uncomplicated pregnancies and their placental synthesis and/or clearance and (b) compare UmA concentrations in uncomplicated pregnancies with those complicated by fetal hypoxia-asphyxia+NE. Three term groups were studied: uncomplicated cesarean delivery without labor (Group 1, n = 15), uncomplicated vaginal delivery with labor (Group 2, n = 15), and perinatal hypoxia-asphyxia+NE (Group 3, n = 8).

RESULTS

UmA GFAP concentrations were lower in Group 1 vs. 2 (P = 0.02) and both demonstrated 100% placental clearance. In contrast, UmA and UmV UCH-L1 concentrations were not unaffected by labor. Group 3 UmA GFAP concentrations were 30- and 8-fold higher than Groups 1 and 2, respectively, P = 0.02, whereas UmA UCH-L1 concentrations were similar in all groups.

CONCLUSIONS

UmA GFAP is derived from the fetus, and circulating levels, which are modulated by placental clearance, increase during uncomplicated labor and more so in the presence of fetal hypoxia-asphyxia+NE, providing a better biomarker than UCH-L1 for hypoxia-asphyxia+NE.

No. 197b-Fetal Health Surveillance: Intrapartum Consensus Guideline

OBJECTIVE

This guideline provides new recommendations pertaining to the application and documentation of fetal surveillance in the intrapartum period that will decrease the incidence of birth asphyxia while maintaining the lowest possible rate of obstetrical intervention. Pregnancies with and without risk factors for adverse perinatal outcomes are considered. This guideline presents an alternative classification system for antenatal fetal non-stress testing and intrapartum electronic fetal surveillance to what has been used previously. This guideline is intended for use by all health professionals who provide intrapartum care in Canada.

OPTIONS

Consideration has been given to all methods of fetal surveillance currently available in Canada.

OUTCOMES

Short- and long-term outcomes that may indicate the presence of birth asphyxia were considered. The associated rates of operative and other labour interventions were also considered.

EVIDENCE

A comprehensive review of randomized controlled trials published between January 1996 and March 2007 was undertaken, and MEDLINE and the Cochrane Database were used to search the literature for all new studies on fetal surveillance antepartum. The level of evidence has been determined using the criteria and classifications of the Canadian Task Force on Preventive Health Care (Table 1).

SPONSOR

This consensus guideline was jointly developed by the Society of Obstetricians and Gynaecologists of Canada and the British Columbia Perinatal Health Program (formerly the British Columbia Reproductive Care Program or BCRCP) and was partly supported by an unrestricted educational grant from the British Columbia Perinatal Health Program. RECOMMENDATION 1: LABOUR SUPPORT DURING ACTIVE LABOUR: RECOMMENDATION 2: PROFESSIONAL ONE-TO ONE CARE AND INTRAPARTUM FETAL SURVEILLANCE: RECOMMENDATION 3: INTERMITTENT AUSCULTATION IN LABOUR: RECOMMENDATION 4: ADMISSION FETAL HEART TEST: RECOMMENDATION 5: INTRAPARTUM FETAL SURVEILLANCE FOR WOMEN WITH RISK FACTORS FOR ADVERSE PERINATAL OUTCOME: When a normal tracing is identified, it may be appropriate to interrupt the electronic fetal monitoring tracing for up to 30 minutes to facilitate periods of ambulation, bathing, or position change, providing that (1) the maternal-fetal condition is stable and (2) if oxytocin is being administered, the infusion rate is not increased (III-B). RECOMMENDATION 6: DIGITAL FETAL SCALP STIMULATION: RECOMMENDATION 7: FETAL SCALP BLOOD SAMPLING: RECOMMENDATION 8: UMBILICAL CORD BLOOD GASES: RECOMMENDATION 9: FETAL PULSE OXIMETRY: RECOMMENDATION 10: ST WAVEFORM ANALYSIS: RECOMMENDATION 11: INTRAPARTUM FETAL SCALP LACTATE TESTING.

Threshold of metabolic acidosis associated with newborn cerebral palsy: medical legal implications

Obstetricians and gynecologists belong to 1 of the medical specialties with the highest rate of litigation claims. Among birth injury cases, those cases with cerebral palsy outcomes account for litigation settlements or judgments often in the millions of dollars. In cases of potential perinatal asphyxia, a threshold level of metabolic acidosis (base deficit ≥12 mmol/L) is necessary to attribute neonatal encephalopathy to an intrapartum hypoxic event. With increasing duration or severity of a hypoxic stress resulting in metabolic acidosis, newborn infant umbilical artery base deficit increases. It may be alleged that, as base deficit levels increase beyond 12 mmol/L, there is an increased likelihood and severity of cerebral palsy. As a corollary, it may be claimed that an earlier delivery (by minutes) would reduce the base deficit and prevent or reduce the severity of cerebral palsy. This issue is of relevance to obstetricians as defendants, because retrospective "expert" analysis of cases may suggest that optimal management decisions would have resulted in an earlier delivery. In addressing the association of metabolic acidosis and cerebral palsy, base deficit should be measured as the extracellular component (base deficit_{extracellular fluid}) rather than the commonly used base deficit_blood. Studies suggest that, beyond the base deficit threshold of 12 mmol/L, the incidence and severity of cerebral palsy does not significantly increase (until ≥20 mmol/L), although the risk of neonatal death rises markedly. Thus, among most infants with hypoxia-associated neonatal encephalopathy, the occurrence of cerebral palsy is unlikely to be impacted by delivery time variation of few minutes, and this argument should not serve as the basis for medical legal claims.

Administration of Bone Marrow-Derived Mononuclear Cells Contributed to the Reduction of Hypoxic-Ischemic Brain Injury in Neonatal Rats

Background/Objective: Perinatal hypoxic-ischemia (HI) causes neonatal death and permanent neurological deficits. Cell therapy using various cell sources has been recently identified as a novel therapy for perinatal HI. Among the available types of cell sources, bone marrow-derived mononuclear cells (BMMNCs) have unique features for clinical application. For example, stem cells can be collected after admission, thus enabling us to perform autologous transplantation. This study aimed to investigate whether the administration of BMMNCs ameliorated HI brain injury in a neonatal rat model. Methods: Seven-day-old rats underwent left carotid artery ligation and were exposed to 8% oxygen for 60 min. BMMNCs were collected from the femurs and tibias of juvenile rats using the Ficoll-Hypaque technique and injected intravenously 24 h after the insult (1 × 10⁵ cells). Active caspase-3, as an apoptosis marker, and ED1, as an activated microglia/macrophage marker, were evaluated immunohistochemically 48 h after the insult (vehicle, n = 9; BMMNC, n = 10). Behavioral assessments using the rotarod treadmill, gait analysis, and active avoidance tests were initiated 3 weeks after the insult (sham, n = 9, vehicle, n = 8; BMMNC, n = 8). After these behavioral tests (6 weeks after the insult), we evaluated the volumes of their hippocampi, cortices, thalami, striata, and globus pallidus. Results: The mean cell densities of the sum of four parts that were positive for active caspase-3 significantly decreased in the BMMNC group (p < 0.05), whereas in the hippocampi, cortices, thalami, and striata cell densities decreased by 42, 60, 56, and 47%, respectively, although statistical significance was not attained. The number of ED1 positive cells for the sum of the four parts also significantly decreased in the BMMNC group compared to the vehicle group (p < 0.05), whereas in each of the four parts the decrease was 35, 39, 47, and 36%, respectively, although statistical significance was not attained. In gait analysis, the BMMNC normalized the contact area of the affected hind paw widened by HI. The volumes of the affected striata and globus pallidus were significantly larger in the BMMNC group than in the control group. Conclusion: These results indicated that the injection of BMMNCs ameliorated HI brain injury in a neonatal rat model.

Deep hypothermia reverses behavioral and histological alterations in a rat model of perinatal asphyxia

The consequences of perinatal asphyxia (PA) include alterations which may manifest as schizophrenia. Characteristic features of this disease include a decrease in specific subpopulations of GABAergic cells and deterioration of social interaction. The purpose of this study is to assess if a deep and short-hypothermic treatment can ameliorate this damage in a model of PA. Rats offsprings were exposed to 19 min of asphyxia by immersing the uterus horns in water at 37 °C followed by 30 min in air at 10 °C that resulted in 15 °C body temperature. At postnatal day 36-38, the rats were tested in the open field and social interaction paradigms and processed for immunostaining of calbindin and reelin. A brief exposure to deep hypothermia reversed the deterioration produced by PA in play soliciting. PA decreased the density of calbindin neurons in layer II of the Anterior Insular Cortex, while deep hypothermia reversed this effect. Paradoxically, in AIC, there was a significant increase in the number of reelin-secreting neurons in layers II and III generated by PA and this increase was reversed by hypothermia. This suggests a compensatory mechanism, where reelin neurons trend to compensate for the loss of calbindin neurons, at least within Anterior Insular Cortex. Finally, the deep hypothermic shock might represent a valuable therapeutic alternative to treat PA.

Umbilical cord milking for neonates who are depressed at birth: a randomized trial of feasibility

OBJECTIVE

To evaluate the feasibility and safety of umbilical cord milking (UCM) in neonates who are depressed at birth.

STUDY DESIGN

This is a quasi-randomized, non-blinded, controlled trial on infants (≥35 weeks) who were depressed at birth. UCM (cord milked three times) was performed during the even months and the neonates born during the odd months were in the control group. Primary outcome was feasibility and safety.

RESULTS

A total of 101 infants were enrolled (50 UCM group and 51 control group) between January 2015 and October 2016. UCM was performed in 95% of infants (59/62) who qualified to receive UCM. There were no significant differences in resuscitation delay, resuscitation efforts, and short-term outcomes between the two groups.

CONCLUSIONS

UCM is feasible for term and late preterm infants who are depressed at birth. A larger clinical trial is needed to evaluate long-term benefits of UCM in neonates with HIE.

Pretreatment with Human Chorionic Gonadotropin Protects the Neonatal Brain against the Effects of Hypoxic-Ischemic Injury

INTRODUCTION

Though the human fetus is exposed to placentally derived human chorionic gonadotropin (hCG) throughout gestation, the role of hCG on the fetal brain is unknown. Review of the available literature appears to indicate that groups of women with higher mean levels of hCG during pregnancy tend to have offspring with lower cerebral palsy (CP) risk. Given that newborn cerebral injury often precedes the development of CP, we aimed to determine whether hCG may protect against the neurodegenerative effects of neonatal brain injury.

METHODS

We utilized the Rice-Vannucci model of neonatal cerebral hypoxia-ischemia (HI) in postnatal day 7 mice to examine whether intraperitoneal administration of hCG 15-18 h prior, 1 h after or immediately following HI decrease brain tissue loss 7 days after injury. We next studied whether hCG has pro-survival and trophic properties in neurons by exposing immature cortical and hippocampal neurons to hCG in vitro and examining neurite sprouting and neuronal survival prior and after glutamate receptor-mediated excitotoxic injury.

RESULTS

We found that intraperitoneal injection of hCG 15 h prior to HI, but not at or 1 h after HI induction, resulted in a significant decrease in hippocampal and striatal tissue loss 7 days following brain injury. Furthermore, hCG reduced N-methyl-d-aspartate (NMDA)-mediated neuronal excitotoxicity in vitro when neurons were continuously exposed to this hormone for 10 days or when given at the time and following neuronal injury. In addition, continuous in vitro administration of hCG for 6-9 days increased neurite sprouting and basal neuronal survival as assessed by at least a 1-fold increase in MAP2 immunoreactivity and a 2.5-fold increase in NeuN + immunoreactivity.

CONCLUSION

Our findings suggest that hCG can decrease HI-associated immature neural degeneration. The mechanism of action for this neuroprotective effect may partly involve inhibition of NMDA-dependent excitotoxic injury. This study supports the hypothesis that hCG during pregnancy has the potential for protecting the developing brain against HI, an important CP risk factor.

Inflammatory cytokine response and reduced heart rate variability in newborns with hypoxic-ischemic encephalopathy

OBJECTIVE

To determine whether systemic inflammation-modulating cytokine expression is related to heart rate variability (HRV) in newborns with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

The data from 30 newborns with HIE were analyzed. Cytokine levels (IL-2, IL-4, IL-6, IL-8, IL-10, IL-13, IL-1β, TNF-α, IFN-λ) were measured either at 24 h of cooling (n=5), 72 h of cooling (n=4) or at both timepoints (n=21). The following HRV metrics were quantified in the time domain: alpha_S, alpha_L, root mean square (RMS) at short time scales (RMS_S), RMS at long time scales (RMS_L), while low-frequency power (LF) and high-frequency power (HF) were quantified in the frequency domain. The relationships between HRV metrics and cytokines were evaluated using mixed-models.

RESULT

IL-6, IL-8, IL-10, and IL-13 levels were inversely related to selected HRV metrics.

CONCLUSION

Inflammation-modulating cytokines may be important mediators in the autonomic dysfunction observed in newborns with HIE.

Neonatal Hypoxia Ischaemia: Mechanisms, Models, and Therapeutic Challenges

Neonatal hypoxia-ischaemia (HI) is the most common cause of death and disability in human neonates, and is often associated with persistent motor, sensory, and cognitive impairment. Improved intensive care technology has increased survival without preventing neurological disorder, increasing morbidity throughout the adult population. Early preventative or neuroprotective interventions have the potential to rescue brain development in neonates, yet only one therapeutic intervention is currently licensed for use in developed countries. Recent investigations of the transient cortical layer known as subplate, especially regarding subplate's secretory role, opens up a novel set of potential molecular modulators of neonatal HI injury. This review examines the biological mechanisms of human neonatal HI, discusses evidence for the relevance of subplate-secreted molecules to this condition, and evaluates available animal models. Neuroserpin, a neuronally released neuroprotective factor, is discussed as a case study for developing new potential pharmacological interventions for use post-ischaemic injury.

Optimal Duration of Continuous Video-Electroencephalography in Term Infants With Hypoxic-Ischemic Encephalopathy and Therapeutic Hypothermia

Continuous video-electroencephalography (EEG) is an important diagnostic and prognostic tool in newborns with hypoxic-ischemic encephalopathy undergoing therapeutic hypothermia. The optimal duration of continuous video-EEG during whole-body hypothermia is not known. We conducted a retrospective study of 35 neonates with hypoxic-ischemic encephalopathy undergoing whole-body hypothermia with continuous video-EEG. EEG ictal changes were detected in 9/35 infants (26%). Of these 9 infants, the seizures were initially observed within 30 minutes of EEG monitoring in 6 (67%), within 24 hours in 2 (22%), and during rewarming in 1 infant (11%). No new seizures were detected between 24-72 hours of therapeutic hypothermia. Background suppression was detected in 14 infants (40%) by 24 hours. In neonates with hypoxic-ischemic encephalopathy undergoing therapeutic hypothermia, continuous video-EEG has the highest diagnostic yield within the first 24 hours and during the rewarming phase. In the absence of prior seizures or antiepileptic therapy, limiting continuous video-EEG to these periods in resource-limited settings may reduce cost during therapeutic hypothermia.

Erythropoietin monotherapy in perinatal asphyxia with moderate to severe encephalopathy: a randomized placebo-controlled trial

OBJECTIVE

Erythropoietin (EPO) is neuroprotective after asphyxia in animal studies. The efficacy and safety of EPO monotherapy in term neonates with hypoxic ischemic encephalopathy (HIE) is uncertain.

STUDY DESIGN

Hundred term neonates with moderate or severe HIE were randomized by random permuted block algorithm to receive either EPO 500 U kg^-1 per dose in 2 ml saline intravenously (50 neonates) on alternate days for a total of five doses with the first dose given by 6 h of age (treatment group) or 2 ml of normal saline (50 neonates) similarly for a total of five doses (placebo group) in a double-blind study. No hypothermia was given. The primary outcome was combined end point of death or moderate or severe disability at mean age of 19 months (s.d., 0.61).

RESULTS

Death or moderate or severe disability occurred in 40% of neonates in the treatment group vs 70% in the placebo group (risk ratio, 0.57; 95% confidence interval (CI) 0.38 to 0.85; P=0.003). Death occurred in 16% of patients in both the groups (risk ratio, 1.0; 95% CI 0.33 to 2.9; P=0.61). The risk of cerebral palsy was lower among survivors in the treatment group (risk ratio, 0.52; 95% CI 0.25 to 1.03; P=0.04) and lesser number of babies were on anticonvulsants at assessment (risk ratio, 0.47; 95% CI 0.20 to 1.01; P=0.03). Neonatal brain magnetic resonance imaging showed more abnormalities in the placebo group (relative risk, 0.66; 95% CI 0.42 to 1.03; P=0.04)). Improvement in other neurological outcomes was not significant.

CONCLUSION

EPO monotherapy reduces the risk of death or disability in term neonates with moderate or severe encephalopathy.

Effect of Temperature on Heart Rate Variability in Neonatal ICU Patients With Hypoxic-Ischemic Encephalopathy

OBJECTIVE

To determine whether measures of heart rate variability are related to changes in temperature during rewarming after therapeutic hypothermia for hypoxic-ischemic encephalopathy.

DESIGN

Prospective observational study.

SETTING

Level 4 neonatal ICU in a free-standing academic children's hospital.

PATIENTS

Forty-four infants with moderate to severe hypoxic-ischemic encephalopathy treated with therapeutic hypothermia.

INTERVENTIONS

Continuous electrocardiogram data from 2 hours prior to rewarming through 2 hours after completion of rewarming (up to 10 hr) were analyzed.

MEASUREMENTS AND MAIN RESULTS

Median beat-to-beat interval and measures of heart rate variability were quantified including beat-to-beat interval SD, low and high frequency relative spectral power, detrended fluctuation analysis short and long α exponents (αS and αL), and root mean square short and long time scales. The relationships between heart rate variability measures and esophageal/axillary temperatures were evaluated. Heart rate variability measures low frequency, αS, and root mean square short and long time scales were negatively associated, whereas αL was positively associated, with temperature (p < 0.01). These findings signify an overall decrease in heart rate variability as temperature increased toward normothermia.

CONCLUSIONS

Measures of heart rate variability are temperature dependent in the range of therapeutic hypothermia to normothermia. Core body temperature needs to be considered when evaluating heart rate variability metrics as potential physiologic biomarkers of illness severity in hypoxic-ischemic encephalopathy infants undergoing therapeutic hypothermia.

Passive hypothermia (≥35 - <36°C) during transport of newborns with hypoxic-ischaemic encephalopathy

BACKGROUND

Hypothermia initiated in the first six hours of life in term infants with hypoxic ischemic encephalopathy reduces the risk of death and severe neurological sequelae. Our study's principal objective was to evaluate transport predictors potentially influencing arrival in NICU (Neonatal Intensive Care Unit) at a temperature ≥35-<36°C.

METHODOLOGY/PRINCIPAL FINDINGS

A multi-centric, prospective cohort study was conducted during 18 months by the three Neonatal Transport Teams and 13 NICUs. Newborns were selected for inclusion according to biological and clinical criteria before transport using passive hypothermia using a target temperature of ≥35-<36°C. Data on 120 of 126 inclusions were available for analysis. Thirty-three percent of the children arrived in NICU with the target temperature of ≥35-<36°C. The mean temperature for the whole group of infants on arrival in NICU was 35.4°C (34.3-36.5). The median age of all infants on arrival in NICU was 3h03min [2h25min-3h56min]. Three infants arrived in NICU with a temperature of <33°C and eleven with a temperature ≥37°C. Adrenaline during resuscitation was associated with a lower mean temperature on arrival in NICU.

CONCLUSIONS/SIGNIFICANCE

Our strategy using ≥35-<36°C passive hypothermia combined with short transport times had little effect on temperature after the arrival of Neonatal Transport Team although did reduce numbers of infants arriving in NICU in deep hypothermia. For those infants where hypothermia was discontinued in NICU our strategy facilitated re-warming. Re-adjustment to a lower target temperature to ≥34.5-<35.5°C may reduce the proportion of infants with high/normothermic temperatures.

Eligibility criteria for therapeutic hypothermia: From trials to clinical practice

AIM

Whole body therapeutic hypothermia (TH) for hypoxic ischaemic encephalopathy was introduced into clinical practice in New South Wales (NSW) and Australian Capital Territory in 2007. State-wide policy adopting the eligibility criteria and practice based on trial-designs was published in 2009.

METHODS

The study was conducted by retrospectively reviewing medical records of all TH infants born between 2007 and 2011 in NSW and Australian Capital Territory to examine if eligibility criteria (assessed against evidence-based policy directives) were met.

RESULTS

A total of 207 infants received TH, 104 (50%) did not meet the eligibility criteria defined in NSW policy directive. Over the 5-year period, the proportion of infants meeting the eligibility criteria did not change. Seventy percent of infants (73 out of 104) not meeting eligibility criteria did not fulfil the criteria for 'evidence of asphyxia', although half of them met 'moderate or severe encephalopathy criterion'. Adverse events (hypotension, coagulopathy and arrhythmia), were more common in the 'criteria met' group than the 'criteria not met' group (89 vs. 71%, P = 0.001). Similar proportions of infants had TH discontinued before 72 h (criteria met: 32 (31%) vs. criteria not met: 27(26%)). Most frequent reason for early cessation was 'palliation' (19/32, 59%) in criteria met and 'clinical improvement' (16/27, 59%) in criteria not met group.

CONCLUSIONS

Many TH infants were treated based on clinician judgement, though not meeting the trial-design policy criteria. Early TH cessation (<72 h) was common. Future studies are warranted on long-term neurodevelopmental outcomes for all infants receiving TH particularly those with early cessation of therapy.

The potentials and limitations of neuro-biomarkers as predictors of outcome in neonates with birth asphyxia

Perinatal asphyxia and its complication, hypoxic-ischemic encephalopathy, are still among the major causes of perinatal mortality and morbidity. Despite accurate standard postnatal monitoring procedures, the post-insult period is crucial because at a time when radiologic pictures are still silent, brain damage may already be at a subclinical stage. Against this background, the measurement of quantitative parameters, such as constituents of nervous tissue, that are able to detect subclinical lesions at a stage when routine brain monitoring procedures are still silent, could be particularly useful. Therefore, in the present review we report the potentials and limitations of biomarkers in predicting outcome in neonates complicated by perinatal asphyxia.

Understanding the Full Spectrum of Organ Injury Following Intrapartum Asphyxia

Birth asphyxia is a significant global health problem, responsible for ~1.2 million neonatal deaths each year worldwide. Those who survive often suffer from a range of health issues including brain damage-manifesting as cerebral palsy (CP)-respiratory insufficiency, cardiovascular collapse, and renal dysfunction, to name a few. Although the majority of research is directed toward reducing the brain injury that results from intrapartum birth asphyxia, the multi-organ injury observed in surviving neonates is of equal importance. Despite the advent of hypothermia therapy for the treatment of hypoxic-ischemic encephalopathy (HIE), treatment options following asphyxia at birth remain limited, particularly in low-resource settings where the incidence of birth asphyxia is highest. Furthermore, although cooling of the neonate results in improved neurological outcomes for a small proportion of treated infants, it does not provide any benefit to the other organ systems affected by asphyxia at birth. The aim of this review is to summarize the current knowledge of the multi-organ effects of intrapartum asphyxia, with particular reference to the findings from our laboratory using the precocial spiny mouse to model birth asphyxia. Furthermore, we reviewed the current treatments available for neonates who have undergone intrapartum asphyxia, and highlight the emergence of maternal dietary creatine supplementation as a preventative therapy, which has been shown to provide multi-organ protection from birth asphyxia-induced injury in our preclinical studies. This cheap and effective nutritional supplement may be the key to reducing birth asphyxia-induced death and disability, particularly in low-resource settings where current treatments are unavailable.

Outcomes in childhood following therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy (HIE)

In this article, we review the childhood outcomes of neonates with birth depression and/or hypoxic-ischemic encephalopathy. The outcomes of these children prior to the era of hypothermia for neuroprotection will first be summarized, followed by discussion of results from randomized controlled trials of therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy. The predictors of outcome in childhood following neonatal HIE using clinical and imaging biomarkers following hypothermia therapy will be described.

Hypothermia-treated neonates with hypoxic-ischemic encephalopathy: Optimal timing of quantitative ADC measurement to predict disease severity

To determine the optimal time window for MR imaging with quantitative ADC measurement in neonatal HIE after hypothermia treatment, a retrospective review was performed on consecutive hypothermia-treated term neonates with HIE, with an initial and follow-up MR imaging within the first two weeks of life. Three neuroradiologists categorized each set of MR imaging as normal, mild, moderate or severe HIE based on a consensus review of the serial imaging. The lowest ADC values from the white matter, corpus callosum, and basal ganglia/thalamus were measured. The ADC values between mild-moderate and severe HIE were compared using a Student's t-test over a range of different time windows. A total of 33 MR imaging examinations were performed on 16 neonates that included three normal, four mild, five moderate, and four severe HIE. The time window of 3-10 days showed a statistically significant decrease in ADC value in severe HIE compared to mild-moderate HIE in all three locations, respectively: white matter 0.5 ± 0.22 versus 0.83 ± 0.27 ( p value 0.01), corpus callosum 0.69 ± 0.19 versus 0.91 ± 0.17 ( p value 0.01), and basal ganglia/thalamus 0.63 ± 0.16 versus 0.98 ± 0.06 ( p value <0.01). The range of 3-10 days is the optimal time window for MR imaging with quantitative ADC after hypothermia treatment.

Perinatal Asphyxia Reduces the Number of Reelin Neurons in the Prelimbic Cortex and Deteriorates Social Interaction in Rats

Obstetrical complications of perinatal asphyxia (PA) can often induce lesions that, in the long-term, manifest as schizophrenia. A deterioration of the medial prefrontal cortex (mPFC) and a reduction in the number of GABAergic neurons are commonly observed in the pathophysiology of schizophrenia. In this study, we investigated the link between PA, reelin and calbindin diminution and psychiatric diseases that involve social interaction deficits. This was achieved by observing the effect of 19 min of asphyxia on both subpopulations of GABAergic neurons. PA was produced by water immersion of fetus-containing uterus horns removed by cesarean section from ready-to-deliver rats. PA generated a significant and specific decrease in the number of reelin-secreting neurons in mPFC layer VI [F(2, 6) = 8.716, p = 0.016; PA vs. vaginal controls (VC), p = 0.03, and PA vs. cesarean controls (CC), p = 0.022]. This reduction reached approximately 60% on average. Changes in the percentage of reelin neurons including all the cortex layers did not achieve a significant outcome but a trend: CC % 10.61 ± 1.34; PA % 8.64 ± 1.71 [F(2, 6) = 1.299, p = 0.33]. In the case of calbindin, there was a significant decrease in cell density in the PA group [2-way repeated-measures ANOVA, F(1, 4) = 13.03, p = 0.0226]. The multiple-comparisons test showed significant differences in the superficial aspect of layer II (Sidak test for multiple comparisons CC vs. PA at 200 µm: p = 0.003). A small, but significant difference could be seen when the distance from the pia mater to the start of layer VI was analyzed (CC mean ± SEM = 768.9 ± 8.382; PA mean ± SEM = 669.3 ± 17.75; p = 0.036). Rats exposed to PA showed deterioration in social interactions, which manifested as a decrease in play soliciting. In this model, which involved severe/moderate asphyxia, we did not find significant changes in locomotive activity or anxiety indicators in the open field task. The loss of reelin neurons could be conducive to the shrinkage of the prelimbic cortex through the reduction in neuropil and the deterioration of the function of this structure.

Long-Term Cognitive Outcomes of Birth Asphyxia and the Contribution of Identified Perinatal Asphyxia to Cerebral Palsy

Neonatal encephalopathy among survivors of presumed perinatal asphyxia is recognized as an important cause of cerebral palsy (CP) and neuromotor impairment. Recent studies suggest that moderate to severe neonatal encephalopathy contributes to a wide range of neurodevelopmental and cognitive impairments among survivors with and without CP. Nearly 1 of every 4 to 5 neonates treated with hypothermia has or develops CP. Neonatal encephalopathy is diagnosed in only approximately 10% of all cases. This article reviews the long-term cognitive outcomes of children with presumed birth asphyxia and describes what is known about its contribution to CP.

Hyperglycemia is associated with poor outcome in newborn infants undergoing therapeutic hypothermia for hypoxic ischemic encephalopathy

BACKGROUND

Therapeutic hypothermia (TH) improves survival and neurodevelopmental outcome in neonatal hypoxic ischemic encephalopathy (HIE). Both, hypoglycemia and hyperglycemia are common in infants with HIE. The relationship between hypoglycemia and hyperglycemia, and immediate outcome has not been well described.

METHODS

A retrospective analysis of newborn infants with HIE (N = 56) was conducted. Blood glucose concentrations recorded during the first 96 hours were noted. Glucose levels of infants who underwent TH (TH group, N = 20) were compared with those that did not undergo TH (No-TH group, N = 36). The relationship between blood glucose and mortality and/or moderate/severe disability was determined.

RESULTS

Mean ± SD blood glucose concentration during the first 24 hours of age was significantly higher in the TH group (148 ± 65 mg/dl), compared with the No-TH group (113 ± 50 mg/dl; p = 0.02), despite a lower glucose infusion rate in the former (4.05 ± 1.77 mg/kg/hr vs. 5.36 ± 2.51 mg/kg/hr; p = 0.04). One hundred percent of infants (n = 9) in the TH group with blood glucose levels >200 mg/dl during the first 24 hours of age died or had moderate/severe disability, compared with 54.5% of those with blood glucose <200 mg/dl in this group (p = 0.03). A similar effect was not present in the No-TH group.

CONCLUSION

Hyperglycemia on the first day portends poor outcome in newborn infants undergoing TH for HIE.