Outcomes of safety and effectiveness in a multicenter randomized, controlled trial of whole-body hypothermia for neonatal hypoxic-ischemic encephalopathy

Neonatal encephalopathy: a systematic review of reported treatment outcomes

BACKGROUND

Neonatal encephalopathy (NE) is a multi-organ condition potentially leading to death or long-term neurodisability. Therapeutic hypothermia is the standard treatment for NE; however, long-term impairments remain common. Studies of new treatments for NE often measure and report different outcomes. Core outcome sets (COSs), a minimum set of outcomes to be measured and reported in all studies for a condition, address this problem. This paper aimed to identify outcomes reported (primary, secondary, adverse events and other reported outcomes) in (1) randomised trials and (2) systematic reviews of randomised trials of interventions for the treatment of NE in the process of developing a COS for interventions for the treatment of NE.

METHODS

We completed a systematic search for outcomes used to evaluate treatments for NE using MEDLINE, Embase, Cochrane CENTRAL, the Cochrane Database of Systematic Reviews and the WHO International Clinical Trials Registry Platform. Two reviewers screened all included articles independently. Outcomes were extracted verbatim, similar outcomes were grouped and outcome domains were developed.

RESULTS

386 outcomes were reported in 116 papers, from 85 studies. Outcomes were categorised into 18 domains. No outcome was reported by all studies, a single study reported 11 outcomes and it was not explicitly stated that outcomes had input from parents.

DISCUSSION

Heterogeneity in reported outcomes means that synthesis of studies evaluating new treatments for NE remains difficult. A COS, that includes parental/family input, is needed to ensure consistency in measuring and reporting outcomes, and to enable comparison of randomised trials.

Pipeline to Neonatal Clinical Transformation: The Importance of Preclinical Data

Historically, neonatal neuroscience boasted a robust and successful preclinical pipeline for therapeutic interventions, in particular for the treatment of hypoxic-ischemic encephalopathy (HIE). However, since the successful translation of therapeutic hypothermia (TH), several high-profile failures of promising adjunctive therapies, in addition to the lack of benefit of TH in lower resource settings, have brought to light critical issues in that same pipeline. Using recent data from clinical trials of erythropoietin as an example, the authors highlight several key challenges facing preclinical neonatal neuroscience for HIE therapeutic development and propose key areas where model development and collaboration across the field in general can ensure ongoing success in treatment development for HIE worldwide.

Cooling during transportation of newborns with hypoxic ischemic encephalopathy using phase change material mattresses in low-resource settings: a randomized controlled trial in Hanoi, Vietnam

OBJECTIVE

To determine the effectiveness of phase-change-material mattress (PCM) during transportation of newborns with hypoxic ischemic encephalopathy (HIE).

STUDY DESIGN

Randomized controlled trial of newborns with HIE from June 2016 to December 2019. Patients were randomized to transport with PCM or without PCM (control) when transferred to a cooling center in northern Vietnam. Primary outcome measure was mortality rate, secondary outcomes including temperature control and adverse effects.

RESULT

Fifty-Two patients in PCM-group and 61 in control group. Median rectal temperature upon arrival was 34.5 °C (IQR 33.5-34.8) in PCM-group and 35.1 °C (IQR 34.5-35.9) in control group (p = 0.023). Median time from birth to reach target temperature was 5.0 ± 1.4 h and 5.5 ± 1.2 h in the respective groups (p = 0.065). 81% of those transported with PCM versus 62% of infants transported without (p = 0.049) had reached target temperature within the 6-h timeframe. There was no record of overcooling (< 32 °C) in any of the groups. The was no difference in mortality rate between the two groups (33% and 34% respectively (p > 0.05)).

CONCLUSION

Phase-change-material can be used as a safe and effective cooling method during transportation of newborns with HIE in low-resource settings.

TRIAL REGISTRATION

The study was retro-prospectively registered in Clinical Trials (04/05/2022, NCT05361473).

Effect of early clinical management on metabolic acidemia in neonates with hypoxic-ischemic encephalopathy

OBJECTIVE

To determine the safety and effectiveness of sodium bicarbonate administration in the management of metabolic acidemia and short-term outcomes in neonates with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

Retrospective cohort study of neonates born at ≥35 weeks of gestation and receiving therapeutic hypothermia. Demographics, pH, lactate, base deficit, treatment, MRI findings, seizure incidence, death prior to discharge were collected.

RESULTS

There was higher mortality (p = 0.010) and injury on MRI (p = 0.008)-primarily deep gray matter (p < 0.001) and cortical injury (p = 0.003)-in the bicarbonate group compared to controls in univariate analysis. The combined outcome of death or abnormal MRI was not significantly associated (OR 1.97, 95% CI 0.80-4.87, p = 0.141) with bicarbonate administration when adjusting for sex, 5-minute Apgar, and initial base deficit.

CONCLUSION

This study demonstrated association between bicarbonate use after HIE and negative short-term outcomes. Future prospective trials could overcome the treatment bias limitation demonstrated in this retrospective study.

Changes in the Treatment and Outcomes of Different Severities of Neonatal Hypoxic Ischemic Encephalopathy in California: A Retrospective Cohort Study

Objective

Evaluate the changes in management and outcomes of Californian infants with hypoxic ischemic encephalopathy (HIE).

Study Design

Infants with HIE were identified from a California administrative birth cohort using ICD codes and divided into two epochs, Epoch 1 (2010-2015) and Epoch 2 (2016-2019). Risk ratios (RR) for therapeutic hypothermia (TH) in each epoch and their outcomes were calculated using log-linear regression.

Results

In this cohort, 4779 infants with HIE were identified. Incidence of HIE in California increased yearly from 0.5/1,000 California births to a peak of 1.5/1,000 births in 2018. The use of TH in infants with mild HIE increased in Epoch 2 compared to Epoch 1. There was no significant difference in outcomes between epochs for infants with mild HIE that received TH.

Conclusion

Significantly more infants with mild HIE received TH since 2015 in California, but no difference in outcomes was found for these patients.

A Comparison of Automatically Extracted Quantitative EEG Features for Seizure Risk Stratification in Neonatal Encephalopathy

PURPOSE

Seizures occur in up to 40% of neonates with neonatal encephalopathy. Earlier identification of seizures leads to more successful seizure treatment, but is often delayed because of limited availability of continuous EEG monitoring. Clinical variables poorly stratify seizure risk, and EEG use to stratify seizure risk has previously been limited by need for manual review and artifact exclusion. The goal of this study is to compare the utility of automatically extracted quantitative EEG (qEEG) features for seizure risk stratification.

METHODS

We conducted a retrospective analysis of neonates with moderate-to-severe neonatal encephalopathy who underwent therapeutic hypothermia at a single center. The first 24 hours of EEG underwent automated artifact removal and qEEG analysis, comparing qEEG features for seizure risk stratification.

RESULTS

The study included 150 neonates and compared the 36 (23%) with seizures with those without. Absolute spectral power best stratified seizure risk with area under the curve ranging from 63% to 71%, followed by range EEG lower and upper margin, median and SD of the range EEG lower margin. No features were significantly more predictive in the hour before seizure onset. Clinical examination was not associated with seizure risk.

CONCLUSIONS

Automatically extracted qEEG features were more predictive than clinical examination in stratifying neonatal seizure risk during therapeutic hypothermia. qEEG represents a potential practical bedside tool to individualize intensity and duration of EEG monitoring and decrease time to seizure recognition. Future work is needed to refine and combine qEEG features to improve risk stratification.

Meconium Aspiration Syndrome, Hypoxic-Ischemic Encephalopathy and Therapeutic Hypothermia-A Recipe for Severe Pulmonary Hypertension?

Hypoxic-ischemic encephalopathy (HIE) is the leading cause of mortality among term newborns globally. Infants born through meconium-stained amniotic fluid are at risk of developing meconium aspiration syndrome (MAS) and HIE. Simultaneous occurrence of MAS and HIE is a perilous combination for newborns due to the risk of persistent pulmonary hypertension of the newborn (PPHN). Moreover, therapeutic hypothermia (TH), which is the current standard of care for the management of HIE, may increase pulmonary vascular resistance (PVR) and worsen PPHN. Infants with MAS and HIE require close cardiorespiratory and hemodynamic monitoring for PPHN. Therapeutic strategies, including oxygen supplementation, ventilation, use of surfactant, inhaled nitric oxide and other pulmonary vasodilators, and systemic vasopressors, play a critical role in the management of PPHN in MAS, HIE, and TH. While TH reduces death or disability in infants with HIE, infants with MAS and HIE undergoing TH need close hemodynamic monitoring for PPHN.

Macroperiodic Oscillations: A Potential Novel Biomarker of Outcome in Neonatal Encephalopathy

PURPOSE

Neonatal encephalopathy (NE) is a common cause of neurodevelopmental morbidity. Tools to accurately predict outcomes after therapeutic hypothermia remain limited. We evaluated a novel EEG biomarker, macroperiodic oscillations (MOs), to predict neurodevelopmental outcomes.

METHODS

We conducted a secondary analysis of a randomized controlled trial of neonates with moderate-to-severe NE who underwent standardized clinical examination, magnetic resonance (MR) scoring, video EEG, and neurodevelopmental assessment with Bayley III evaluation at 18 to 24 months. A non-NE cohort of neonates was also assessed for the presence of MOs. The relationship between clinical examination, MR score, MOs, and neurodevelopmental assessment was analyzed.

RESULTS

The study included 37 neonates with 24 of whom survived and underwent neurodevelopmental assessment (70%). The strength of MOs correlated with severity of clinical encephalopathy. MO strength and spread significantly correlated with Bayley III cognitive percentile ( P = 0.017 and 0.046). MO strength outperformed MR score in predicting a combined adverse outcome of death or disability ( P = 0.019, sensitivity 100%, specificity 77% vs. P = 0.079, sensitivity 100%, specificity 59%).

CONCLUSIONS

MOs are an EEG-derived, quantitative biomarker of neurodevelopmental outcome that outperformed a comprehensive validated MRI injury score and a detailed systematic discharge examination in this small cohort. Future work is needed to validate MOs in a larger cohort and elucidate the underlying pathophysiology of MOs.

Impact of persistent pulmonary hypertension and oxygenation on brain injury in neonates with neonatal encephalopathy treated with therapeutic hypothermia

OBJECTIVE

To investigate the effects of persistent pulmonary hypertension (PPHN) and oxygenation on outcome of neonates with neonatal encephalopathy (NE) treated with therapeutic hypothermia (TH).

STUDY DESIGN

We compared the outcome of neonates with NE treated with TH with or without PPHN.

RESULTS

384 neonates with NE were treated with TH; 24% had PPHN. The fraction of inspired oxygen was higher in the first 4 days of life (p < 0.001) in neonates with PPHN. They had a significantly lower arterial partial pressure of oxygen in the first 4 days of life (p = 0.005) and higher on days 3-4 of life (p < 0.001). They were more often intubated (p < 0.001) and more often had concomitant hypotension (p < 0.001). They had higher mortality (p = 0.009) and more often developed brain injury (p = 0.02).

CONCLUSION

PPHN occurred frequently in neonates with NE treated with TH and was associated with a higher incidence of adverse outcome.

Hypoxic-ischaemic encephalopathy code: A systematic review for resource-limited settings

It is estimated that 96% of infants with hypoxic-ischaemic encephalopathy (HIE) are born in resource-limited settings with no capacity to provide the standard of care that has been established for nearly 15 years in high-resource countries, which includes therapeutic hypothermia (TH), continuous electroencephalographic monitoring and magnetic resonance imaging (MRI) in addition to close vital signs and haemodynamic monitoring. This situation does not seem to be changing; however, even with these limitations, currently available knowledge can help improve the care of HIE patients in resource-limited settings. The purpose of this systematic review was to provide, under the term "HIE Code", evidence-based recommendations for feasible care practices to optimise the care of infants with HIE and potentially help reduce the risks associated with comorbidity and improve neurodevelopmental outcomes. The content of the HIE code was grouped under 9 headings: (1) prevention of HIE, (2) resuscitation, (3) first 6h post birth, (4) identification and grading of encephalopathy, (5) seizure management, (6) other therapeutic interventions, (7) multiple organ dysfunction, (8) diagnostic tests and (9) family care.

Asphyxia, Therapeutic Hypothermia, and Pulmonary Hypertension

Neonates with a perinatal hypoxic insult and subsequent neonatal encephalopathy are at risk of acute pulmonary hypertension (aPH) in the transitional period. The phenotypic contributors to aPH following perinatal asphyxia include a combination of hypoxic vasoconstriction of the pulmonary vascular bed, right heart dysfunction, and left heart dysfunction. Therapeutic hypothermia is the standard of care for neonates with moderate-to-severe hypoxic ischemic encephalopathy. This review summarizes the underlying risk factors, causes of aPH in neonates with perinatal asphyxia, discusses the unique phenotypical contributors to disease, and explores the impact of the initial insult and subsequent therapeutic hypothermia on aPH.

Neonatal Hypoxic-Ischemic Encephalopathy and Hypothermia Treatment

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

Persistent pulmonary hypertension and short-term neurological outcomes in infants with moderate to severe hypoxic ischemic encephalopathy

BACKGROUND

Our aim was to investigate the relationship between persistent pulmonary hypertension of the newborn (PPHN), short-term brain injury or death, and clinical parameters in infants with moderate to severe hypoxic ischemic encephalopathy (HIE).

METHODS

Retrospective single-center cohort study of 274 HIE infants, 230 underwent Therapeutic Hypothermia (TH). Primary outcome was severe HIE brain injury on MRI and/or death within the first month of life in relation to presence and severity of PPHN (clinical or echocardiographic). Secondary outcomes were HIE brain injury pattern, abnormal electroencephalogram (EEG), seizures, clinical, and laboratory differences. A logistic regression model was performed to evaluate PPHN presence and severity as risk factor for brain injury or death.

RESULTS

The combined outcome of severe brain injury or death was higher in the clinical PPHN group vs non-PPHN (32.6 vs 22.8%, p = 0.014). There was no difference in brain injury, seizure burden or EEG abnormalities associated with PPHN, despite those with PPHN being sicker with higher ventilation needs and worse laboratory values than those without. Mortality had a strong correlation with echocardiographic PPHN with the highest incidence in severe (36%) vs moderate (7.7%) vs mild PPHN (10%, p = 0.002). Highest mortality had those with 'early exit' who did not complete 72 hours of TH (71.4%).

CONCLUSIONS

In infants with HIE, PPHN was not associated with increased risk of brain injury as evident on MRI, nor seizure burden, despite being sicker with worse laboratory values. However, mortality rates were higher the worse the PPHN, especially with early exit from TH.

Growth and developmental outcomes of infants with hypoxic ischemic encephalopathy

Despite advances in obstetric care, hypoxic ischemic encephalopathy (HIE) remains a significant disease burden. We determined the national trends of HIE prevalence, therapeutic hypothermia (TH) use, mortality, and outcomes from 2012 to 2019. This study included term infants diagnosed with HIE between 2012 and 2019 from the National Health Insurance Service database. The prevalence of HIE was 2.4 per 1000 births without significant change during the period. TH was performed in approximately 6.7% of infants with HIE, and the annual variation ranged from 2.4 to 12.5%. The mortality among all term infants with HIE was 4.6%. The mortality rate among infants with HIE and TH significantly declined from 40 to 16.9% during the eight years. Infants with TH had higher mortality, increased use of inhaled nitric oxide, and more invasive ventilator use, indicating greater disease severity in the TH group. Infants with TH also showed significantly poorer outcomes, including delayed development, cerebral palsy, sensorineural hearing loss, and seizure, compared to infants without TH (p < 0.0001). With the increasing application of TH, mortality and developmental outcomes among infants with HIE have been improving in the past eight years in Korea. Further efforts to improve outcomes should be needed.

Predictive performance of multiple organ dysfunction in asphyxiated newborns treated with therapeutic hypothermia on 24-month outcome: a cohort study

BACKGROUND

Perinatal asphyxia may be followed by multiple organ dysfunction (MOD) and is often included in prognostication of the individual patient, but evidence of discriminating accuracy is lacking. The aim of this study was to assess whether MOD in asphyxiated neonates during therapeutic hypothermia (TH) predicts mortality or neurodevelopmental impairment (NDI) at 24 months of age and which peripartum variables are associated with the onset of MOD.

METHODS

A retrospective analysis of a prospective cohort study of asphyxiated newborns undergoing TH was performed. MOD was defined as dysfunction of the brain (encephalopathy) combined with two or more organ systems. Outcome was routinely assessed by standardised developmental testing at the age of 24 months. The predictive accuracy of MOD on the combined outcome and its components (death and NDI) was expressed as areas under the receiver operating characteristic curves (AUROCs). The associations of peripartum variables and development of MOD were expressed as ORs and their CIs.

RESULTS

189 infants (median gestation 40 (range 36-42 weeks) with moderate to severe hypoxic ischaemic encephalopathy were included. 47% developed MOD. The prediction of the combined 24-month outcome or its components showed AUROCs <0.70. Associated with MOD were pH at birth (OR 0.97, CI 0.95 to 0.99), lactate at birth (OR 1.09, CI 1.04 to 1.15), Base Excess (BE) at birth (OR 0.94, CI 0.90 to 0.99) and epinephrine administration during resuscitation (OR 2.09, CI 1.02 to 4.40).

CONCLUSION

MOD has a low discriminating accuracy in predicting mortality or NDI at 24 months age and might not be useful for prognostication. Signs of acid-base disturbance and adrenalin use at birth are associated with the development of MOD.

Troponin I, CK-MB, and inotropic score in hypoxic-ischemic encephalopathy and associated infant mortality

PURPOSE

Cardiovascular dysfunction is common in hypoxic-ischemic encephalopathy (HIE), which is one of the leading causes of multi-organ failure in neonates. We aimed to assess troponin I and creatine kinase myocardial band (CK-MB) levels, inotropic score (IS) in HIE patients, and their associations with HIE staging and mortality.

METHOD

The medical records of all HIE infants admitted to our unit between 2016 and 2018 were retrospectively analyzed. Demographic characteristics of the infants, seizures, anticonvulsive therapies, maximum inotrope doses, and the derived IS (dopamine dose [µg/kg/min] + dobutamine dose [µg/kg/min] + 100 × epinephrine dose [µg/kg/min]) and CK-MB and troponin-I levels obtained in the first six hours of life were compared according to HIE staging. Comparisons between survivors and non-survivors were made.

RESULTS

The study included data from 195 patients. Twenty-five patients were classified as stage 3, 116 as stage 2, and 54 as stage 1 HIE. Median Troponin-I, CK-MB level, and IS significantly differed by HIE staging (p < 0.01). The deceased infants had significantly higher median troponin I level [0.36 (0.02-3) vs. 0.16 (0.01-1.1) ng/ml; p = 0.006], median IS [20 (5-120) vs. 5 (5-10); p < 0.001], however, CK-MB values were comparable with survivors [129 (51-300) vs. 60.7 (31-300) ng/ml; p = 0.57]. The area under the curve was 0.93 for IS and 0.81 for Troponin I to predict mortality.

CONCLUSION

Troponin I, CK-MB, and IS could be successfully used as disease severity markers in HIE furthermore, troponin I and IS, are good predictors of mortality. These results need to be confirmed with larger prospective multi-center studies.

Brain organoids for hypoxic-ischemic studies: from bench to bedside

Our current knowledge regarding the development of the human brain mostly derives from experimental studies on non-human primates, sheep, and rodents. However, these studies may not completely simulate all the features of human brain development as a result of species differences and variations in pre- and postnatal brain maturation. Therefore, it is important to supplement the in vivo animal models to increase the possibility that preclinical studies have appropriate relevance for potential future human trials. Three-dimensional brain organoid culture technology could complement in vivo animal studies to enhance the translatability of the preclinical animal studies and the understanding of brain-related disorders. In this review, we focus on the development of a model of hypoxic-ischemic (HI) brain injury using human brain organoids to complement the translation from animal experiments to human pathophysiology. We also discuss how the development of these tools provides potential opportunities to study fundamental aspects of the pathophysiology of HI-related brain injury including differences in the responses between males and females.

Correlation of Different MRI Scoring Systems with Long-Term Cognitive Outcome in Cooled Asphyxiated Newborns

(1) Background: Cerebral MRI plays a significant role in assessing the extent of brain injury in neonates with neonatal encephalopathy after perinatal asphyxia. Over the last decades, several MRI scoring systems were developed to enhance the predictive accuracy of MRI. The aim of this study was to validate the correlation of four established MRI scoring systems with cognitive long-term outcomes in cooled asphyxiated newborns. (2) Methods: Forty neonates with neonatal encephalopathy treated with therapeutic hypothermia were included in this retrospective study. The MRI scans from the second week of life were scored using four existing MRI scoring systems (Barkovich, NICHD, Rutherford, and Weeke). The patients' outcome was assessed with the Bayley Scales of Infant Development (BSID-III) at the age of 2 years. To evaluate the correlation between the MRI scoring system with the cognitive scores of BSID-III, the correlation coefficient was calculated for each scoring system. (3) Results: All four MRI scoring systems showed a significant correlation with the cognitive scores of BSID-III. The strongest correlation was found between the Weeke Score (r2 = 0.43), followed by the Rutherford score (r2 = 0.39), the NICHD score (r2 = 0.22), and the Barkovich score (r2 = 0.17). (4) Conclusion: Our study confirms previously published results in an independent cohort and indicates that the Weeke and Rutherford scores have the strongest correlation with the cognitive score of BSID-III in cooled asphyxiated newborns.

Adequacy of sedation analgesia to support the comfort of neonates undergoing therapeutic hypothermia and its impact on short-term neonatal outcomes

Objectives

We aimed to evaluate (1) whether sedation analgesia (SA) used during therapeutic hypothermia (TH) was efficient to support the wellbeing of neonates with hypoxic-ischemic encephalopathy, (2) the SA level and its adjustment to clinical pain scores, and (3) the impact of inadequate SA on short-term neonatal outcomes evaluated at discharge.

Methods

This was an observational retrospective study performed between 2011 and 2018 in two level III centers in Alsace, France. We analyzed the wellbeing of infants by using the COMFORT-Behavior (COMFORT-B) clinical score and SA level during TH, according to which we classified infants into four groups: those with excess SA, adequate SA, lack of SA, and variability of SA. We analyzed the variations in doses of SA and their justification. We also determined the impact of inadequate SA on neonatal outcomes at discharge by multivariate analyses with multinomial regression, with adequate SA as the reference.

Results

A total of 110 patients were included, 89 from Strasbourg university hospital and 21 from Mulhouse hospital. The COMFORT-B score was assessed 95.5% of the time. Lack of SA was mainly found on the first day of TH (15/110, 14%). In all, 62 of 110 (57%) infants were in excess of SA over the entire duration of TH. Most dose variations were related to clinical pain scores. Inadequate SA was associated with negative short-term consequences. Infants with excess of SA had a longer duration of mechanical ventilation [mean ratio 1.46, 95% confidence interval (CI), 1.13-1.89, p = 0.005] and higher incidence of abnormal neurological examination at discharge (odds ratio 2.61, 95% CI, 1.10-6.18, p = 0.029) than infants with adequate SA.

Discussion

Adequate SA was not easy to achieve during TH. Close and regular monitoring of SA level may help achieve adequate SA. Excess of SA can be harmful for newborns with hypoxic-ischemic encephalopathy who are undergoing TH.

Changing populations being treated with ECMO in the neonatal period - who are the others?

Extracorporeal life support via extracorporeal membrane oxygenation (ECMO) has served the sickest of neonates for almost 50 years. Naturally, the characteristics of neonates receiving ECMO have changed. Advances in care have averted the need for ECMO for some, while complex cases with uncertain outcomes, previously not eligible for ECMO, are now considered. Characterizing the disease states and outcomes for neonates on ECMO is challenging as many infants do not fall into classic categories, i.e. meconium aspiration syndrome (MAS), respiratory distress syndrome (RDS), or congenital diaphragmatic hernia (CDH). Since 2017, over one third of neonatal respiratory ECMO runs reported to the Extracorporeal Life Support Organization Registry are grouped as Other, a catch-all that encompasses those with a diagnosis not included in the classic categories. This review summarizes the historical neonatal ECMO population, reviews advances in therapy and technology impacting neonatal care, and addresses the unknowns in the ever-growing category of Other.

Hemostasis in Neonates with Perinatal Hypoxia—Laboratory Approach: A Systematic Review

Birth asphyxia, with an estimated prevalence of 1 to 6 per 1,000 live births, may lead to multiorgan dysfunction due to impaired oxygen and/or blood supply to various organ systems, including the hemostatic system. Coagulopathy, a common complication of perinatal asphyxia, has been described since the 1960s. The aim of this study was to systematically review the literature for records on the use of hemostasis tests in the evaluation of coagulation disorders, in neonates who had suffered from perinatal hypoxia or asphyxia. We identified published studies by searching PubMed and Scopus, up until April 2022. The literature search retrieved 37 articles fulfilling the inclusion criteria of the review. According to the bibliography, thrombocytopenia is commonly associated with perinatal hypoxia/asphyxia. The thrombocytopenia is usually described as mild and platelets return to normal levels by the 10th day of life. Additionally, hypoxic neonates usually present with a hypocoagulable profile, as reflected by the prolongation of standard coagulation tests, including prothrombin time, activated partial thromboplastin time, and international normalized ratio, findings commonly associated with disseminated intravascular coagulation, and by the reduction of the levels of the physiologic inhibition of coagulation system. A few studies thus far using ROTEM/TEG in hypoxic neonates have come to the same conclusion as well; hypoxic newborns seem to be characterized by a hypocoagulable profile compared with healthy neonates. It should be emphasized, however, that standard coagulation tests provide only a rough estimation of the true bleeding or thrombotic risk of hypoxic neonates. On the contrary, viscoelastic methods seem to be more precise in the early detection of hemostasis disorders in the neonatal population. However, until now, there was uncertainty as to the most appropriate coagulation assays for diagnosis and management of coagulation derangement in neonates with perinatal hypoxia indicating the need for further research on this field.

Availability of active therapeutic hypothermia at birth for neonatal hypoxic ischaemic encephalopathy: a UK population study from 2011 to 2018

OBJECTIVE

Therapeutic hypothermia (TH) commenced soon after birth for neonatal hypoxic ischaemic encephalopathy (HIE) improves survival and reduces neurodisability. Availability of active TH at the place of birth (Immediate-TH) in the UK is unknown.

DESIGN

Population-based observational study.

SETTING

UK maternity centres.

PATIENTS

5 975 056 births from 2011 to 2018.

INTERVENTION METHODS

For each maternity centre, the year active Immediate-TH was available and the annual birth rates were established. Admission temperatures of infants with HIE transferred from non-tertiary centres with and without Immediate-TH were compared.

MAIN OUTCOME MEASURES

Quantify the annual number of births with access to Immediate-TH. Secondary outcomes included temporal changes in Immediate-TH and admission temperatures for infants requiring transfer to tertiary centres.

RESULTS

In UK maternity centres, 75 of 194 (38.7%) provided Immediate-TH in 2011 rising to 95 of 192 (49.5%, p=0.003) in 2018 with marked regional variations. In 2011, 394 842 (51.2%) of 771 176 births had no access to Immediate-TH compared with 276 258 (39.3%) of 702 794 births in 2018 (p<0.001). More infants with HIE arrived in the therapeutic temperature range (76.5% vs 67.3%; OR 1.58, 95% CI 1.25 to 2.0, p<0.001) with less overcooling (10.6% vs 14.3%; OR 0.71, 95% CI 0.51 to 0.98, p=0.036) from centres with Immediate-TH compared with those without.

CONCLUSIONS

Availability of active Immediate-TH has slowly increased although many newborns still have no access and rely on transport team arrival to commence active TH. This is associated with delayed optimal hypothermic management. Provision of Immediate-TH across all units, with appropriate training and support, could improve care of infants with HIE.

Therapeutic hypothermia in neonatal hypoxic encephalopathy: A systematic review and meta-analysis

Background

Therapeutic hypothermia (TH) is regarded as the most efficacious therapy for neonatal hypoxic encephalopathy. However, limitations in previous systematic reviews and the publication of new data necessitate updating the evidence. We conducted this up-to-date systematic review to evaluate the effects of TH in neonatal encephalopathy on clinical outcomes.

Methods

In this systematic review and meta-analysis, we searched Medline, Cochrane Library, Embase, LIVIVO, Web of Science, Scopus, CINAHL, major trial registries, and grey literature (from inception to October 31, 2021), for randomized controlled trials (RCT) comparing TH vs normothermia in neonatal encephalopathy. We included RCTs enrolling neonates (gestation ≥35 weeks) with perinatal asphyxia and encephalopathy, who received either TH (temperature ≤34°C) initiated within 6 hours of birth for ≥48 hours, vs no cooling. We excluded non-RCTs, those with delayed cooling, or cooling to >34°C. Two authors independently appraised risk-of-bias and extracted data on mortality and neurologic disability at four time points: neonatal (from randomization to discharge/death), infancy (18-24 months), childhood (5-10 years), and long-term (>10 years). Other outcomes included seizures, EEG abnormalities, and MRI findings. Summary data from published RCTs were pooled through fixed-effect meta-analysis.

Results

We identified 36 863 citations and included 39 publications representing 29 RCTs with 2926 participants. Thirteen studies each had low, moderate, and high risk-of-bias. The pooled risk ratios (95% confidence interval, CI) were as follows: neonatal mortality: 0.87 (95% CI = 0.75, 1.00), n = 2434, I² = 38%; mortality at 18-24 months: 0.88 (95% CI = 0.78, 1.01), n = 2042, I² = 51%; mortality at 5-10 years: 0.81 (95% CI = 0.62, 1.04), n = 515, I² = 59%; disability at 18-24 months: 0.62 (95% CI = 0.52, 0.75), n = 1440, I² = 26%; disability at 5-10 years: 0.68 (95% CI = 0.52, 0.90), n = 442, I² = 3%; mortality or disability at 18-24 months: 0.78 (95% CI = 0.72, 0.86), n = 1914, I² = 54%; cerebral palsy at 18-24 months: 0.63 (95% CI = 0.50, 0.78), n = 1136, I² = 39%; and childhood cerebral palsy: 0.63 (95% CI = 0.46, 0.85), n = 449, I² = 0%. Some outcomes showed significant differences by study-setting; the risk ratio (95% CI) for mortality at 18-24 months was 0.79 (95% CI = 0.66,0.93), n = 1212, I² = 7% in high-income countries, 0.67 (95% CI = 0.41, 1.09), n = 276, I² = 0% in upper-middle-income countries, and 1.18 (95% CI = 0.94, 1.47), n = 554, I² = 75% in lower-middle-income countries. The corresponding pooled risk ratios for ‘mortality or disability at 18-24 months’ were 0.77 (95% CI = 0.69, 0.86), n = 1089, I² = 0%; 0.56 (95% CI = 0.41, 0.78), n = 276, I² = 30%; and 0.92 (95% CI = 0.77, 1.09), n = 549, I² = 86% respectively. Trials with low risk of bias showed risk ratio of 0.97 (95% CI = 0.80, 1.16, n = 1475, I² = 62%) for neonatal mortality, whereas trials with higher risk of bias showed 0.71 (95% CI = 0.55, 0.91), n = 959, I² = 0%. Likewise, risk ratio for mortality at 18-24 months was 0.96 (95% CI = 0.83, 1.13), n = 1336, I² = 58% among low risk-of-bias trials, but 0.72 (95% CI = 0.56, 0.92), n = 706, I² = 0%, among higher risk of bias trials.

Conclusions

Therapeutic hypothermia for neonatal encephalopathy reduces neurologic disability and cerebral palsy, but its effect on neonatal, infantile and childhood mortality is uncertain. The setting where it is implemented affects the outcomes. Low(er) quality trials overestimated the potential benefit of TH.

Value of brain damage biomarkers in cerebrospinal fluid in neonates with hypoxic-ischemic brain injury

Hypoxic-ischemic encephalopathy is one of the leading causes of death and neurological disability worldwide. A key issue in neonates with hypoxic-ischemic encephalopathy is accurately establishing the occurrence and severity of brain lesions soon after a perinatal hypoxic-ischemic event. This is crucial to help with prognosis; guide clinical decision-making, including the use of other therapies; and improve family counseling. Neurobiochemical markers may offer a quantitative approximation for estimating the severity of brain damage and identifying infants who have a high risk of further neurological disability. In addition, they should help identify those neonates who would benefit most from the implementation of other neuroprotective and neuroreparative interventions. Despite considerable progress in this area, relatively few studies have been aimed at examining the clinical utility of brain-specific proteins in cerebrospinal fluid, an important opening to characterizing pathological phenomena associated with hypoxic-ischemic brain injury.

Neurodevelopmental outcome following hypoxic ischaemic encephalopathy and therapeutic hypothermia is related to right ventricular performance at 24-hour postnatal age

OBJECTIVE

Our aim was to determine whether right ventricular (RV) dysfunction at 24-hour postnatal age predicts adverse developmental outcome among patients with hypoxic ischaemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH).

DESIGN

Neonates≥35 weeks with HIE/TH were enrolled in a physiological study in the neonatal period (n=46) and either died or underwent neurodevelopmental follow-up at 18 months (n=43). The primary outcome was a composite of death, diagnosis of cerebral palsy or any component of the Bayley Scores of Infant Development III<70. We hypothesised that tricuspid annulus plane systolic excursion (TAPSE) <6 mm and/or RV fractional area change (RV-FAC) <0.29 would predict adverse outcome.

RESULTS

Nine patients died and 34 patients were followed up at a mean age of 18.9±1.4 months. Both indices of RV systolic performance were abnormal in 15 (35%) patients, TAPSE <6 mm only was abnormal in 4 (9%) patients and RV-FAC <0.29 only was abnormal in 5 (12%) patients (19 had with normal RV function). Although similar at admission, neonates with RV dysfunction had higher cardiovascular and neurological illness severity by 24 hours than those without and severe MRI abnormalities (70% vs 53%, p=0.01) were more common. On logistic regression, TAPSE <6 mm (OR 3.6, 95% CI 1.2 to 10.1; p=0.017) and abnormal brain MRI [OR 21.7, 95% CI 1.4 to 336; p=0.028) were independently associated with adverse outcome. TAPSE <6 mm predicted outcome with a 91% sensitivity and 81% specificity.

CONCLUSIONS

The role of postnatal cardiovascular function on neurological outcomes among patients with HIE who receive TH merits further study. Quantitative measurement of RV function at 24 hours may provide an additional neurological prognostic tool.

Outcomes of neonatal hypoxic-ischaemic encephalopathy in centres with and without active therapeutic hypothermia: a nationwide propensity score-matched analysis

OBJECTIVE

Therapeutic hypothermia (TH) for neonatal hypoxic-ischaemic encephalopathy (HIE), delivered mainly in tertiary cooling centres (CCs), reduces mortality and neurodisability. It is unknown if birth in a non-cooling centre (non-CC), without active TH, impacts short-term outcomes.

DESIGN

Retrospective cohort study using National Neonatal Research Database and propensity score-matching.

SETTING

UK neonatal units.

PATIENTS

Infants ≥36 weeks gestational age with moderate or severe HIE admitted 2011-2016.

INTERVENTIONS

Birth in non-CC compared with CC.

MAIN OUTCOME MEASURES

Primary outcome was survival to discharge without recorded seizures. Secondary outcomes were recorded seizures, mortality and temperature on arrival at CCs following transfer.

RESULTS

5059 infants were included with 2364 (46.7%) born in non-CCs. Birth in a CC was associated with improved survival without seizures (35.1% vs 31.8%; OR 1.15, 95% CI 1.02 to 1.31; p=0.02), fewer seizures (60.7% vs 64.6%; OR 0.84, 95% CI 0.75 to 0.95, p=0.007) and similar mortality (15.8% vs 14.4%; OR 1.11, 95% CI 0.93 to 1.31, p=0.20) compared with birth in a non-CC. Matched infants from level 2 centres only had similar results, and birth in CCs was associated with greater seizure-free survival compared with non-CCs. Following transfer from a non-CC to a CC (n=2027), 1362 (67.1%) infants arrived with a recorded optimal therapeutic temperature but only 259 (12.7%) of these arrived within 6 hours of birth.

CONCLUSIONS

Almost half of UK infants with HIE were born in a non-CC, which was associated with suboptimal hypothermic treatment and reduced seizure-free survival. Provision of active TH in non-CC hospitals prior to upward transfer warrants consideration.

Experience of cases with inhaled nitric oxide and therapeutic hypothermia

BACKGROUND

Neonates with hypoxic-ischemic encephalopathy (HIE) on therapeutic hypothermia (TH) therapy may show persistent pulmonary hypertension of the newborn (PPHN). In Japan, the reported mortality rate is lower than in the US, possibly due to treatment differences of newborns with moderate to severe HIE and PPHN. This study aimed to determine the feasibility and long-term outcomes of inhaled nitric oxide (iNO) and TH therapy in newborns with moderate to severe HIE and PPHN.

METHODS

This was a retrospective review of neonates with moderate to severe HIE that were treated with TH from 2008 to 2017 at a large medical center in Japan. We documented their long-term neurological prognosis, measuring their developmental and Gross Motor Function Classification System level at 18 months old.

RESULTS

A total of 37 neonates with moderate to severe HIE underwent TH therapy and six of them were started with iNO therapy for PPHN. iNO with TH was safely administered to all six newborns with moderate to severe HIE with PPHN. In two neonates TH was discontinued because of intraventricular hemorrhage (IVH) and severe hypotension. Neurological outcomes were similar in newborns who were treated with iNO and TH and those who were treated with TH alone.

CONCLUSION

These initial findings suggest that monitoring hematological and cardiovascular status is important with iNO for severe asphyxia in infants with PPHN. Safer and more feasible protocols are needed for when iNO and TH therapy are administered together.

Prognostic Value of Various Diagnostic Methods for Long-Term Outcome of Newborns After Hypoxic-Ischemic Encephalopathy Treated With Hypothermia

INTRODUCTION

Prediction of outcome in newborns with hypoxic-ischemic encephalopathy (HIE) has been modulated by hypothermia treatment (HT). We assessed the predictive value of diagnostic methods commonly used in neonates with HIE for short-term neurodevelopmental outcome and long-term neurological outcome.

MATERIALS AND METHODS

This longitudinal cohort study followed up 50 term newborns who underwent HT after HIE between July 2006 and August 2015, until preschool age. We estimated sensitivity and specificity for short-term neurodevelopmental outcome at 18 months and long-term neurological outcome at five years based on Amiel-Tison Neurological Assessment (ATNA), electroencephalography (EEG), and magnetic resonance imaging (MRI) performed in the neonatal period.

RESULTS

The accuracy of all neonatal methods tested was higher for long-term neurological outcome compared to the predictive accuracy for short-term neurodevelopmental outcome at 18-24 months. Sensitivity and specificity in predicting unfavorable long-term neurological outcome were: MRI (sensitivity 1.0 [95%CI 0.96-1.0]; specificity 0.91 [95%CI 0.86-1.0]), EEG (sensitivity 0.94 [95%CI 0.71-1.0]; specificity 1.0 [95% CI 0.89-1.0]), and ATNA (sensitivity 0.94 [95%CI 0.71-1.0]; specificity 0.91 [95%CI 0.76-0.98]).

CONCLUSION

MRI is a powerful predictor of long-term neurological outcome when performed in the first week after HIE in HT treated infants, as are EEG and ATNA performed in the second or third week postnatally.

Development, Reliability, and Testing of a New Rating Scale for Neonatal Encephalopathy

OBJECTIVE

To develop and test the Neonatal Encephalopathy-Rating Scale (NE-RS), a new rating scale to grade the severity of neonatal encephalopathy (NE) within the first 6 hours after birth.

STUDY DESIGN

A 3-phase process was conducted: (1) design of a comprehensive scale that would be specific, sensitive, brief, and unsophisticated; (2) evaluation in a cohort of infants with neonatal encephalopathy and healthy controls; and (3) validation with brain magnetic resonance imaging findings and outcome at 2 years of age.

RESULTS

We evaluated the NE-RS in 54 infants with NE and 28 healthy infants. The NE-RS had excellent internal consistency (Cronbach alpha coefficient: 0.93 [95% CI 0.86-0.94]) and reliability (intraclass correlation coefficient in the NE cohort 0.996 [95% CI 0.993-0.998; P < .001]). Alertness, posture, motor response, and spontaneous activity were the top discriminators for degrees of NE. The cut-off value for mild vs moderate NE was 8 points (area under the curve [AUC] 0.99, 95% CI 0.85-1.00) and for moderate vs severe NE, 30 points (AUC 0.93, 95% CI 0.81-0.99). The NE-RS was significantly correlated with the magnetic resonance imaging score (Spearman Rho 0.77, P < .001) and discriminated infants who had an adverse outcome (AUC 0.91, 95% CI 0.83-0.99, sensitivity 0.82, specificity 0.81, positive predictive value 0.87, negative predictive value 0.74).

CONCLUSIONS

The NE-RS is reliable and performs well in reflecting the severity of NE within the first 6 hours after birth. This tool could be useful when assessing clinical criteria for therapeutic hypothermia in NE.

Venovenous versus venoarterial extracorporeal membrane oxygenation among infants with hypoxic-ischemic encephalopathy: is there a difference in outcome?

OBJECTIVE

Our hypothesis was that among infants with hypoxic-ischemic encephalopathy (HIE), venoarterial (VA), compared to venovenous (VV), extracorporeal membrane oxygenation (ECMO) is associated with an increased risk of mortality or intracranial hemorrhage (ICH).

DESIGN/METHODS

Retrospective cohort analysis of infants in the Children's Hospitals Neonatal Database from 2010 to 2016 with moderate or severe HIE, gestational age ≥36 weeks, and ECMO initiation <7 days of age. The primary outcome was mortality or ICH.

RESULTS

Severe HIE was more common in the VA ECMO group (n = 57), compared to the VV ECMO group (n = 53) (47.4% vs. 26.4%, P = 0.02). VA ECMO was associated with a significantly higher risk of death or ICH [57.9% vs. 34.0%, aOR 2.39 (1.08-5.28)] and mortality [31.6% vs. 11.3%, aOR 3.06 (1.08-8.68)], after adjusting for HIE severity.

CONCLUSIONS

In HIE, VA ECMO was associated with a higher incidence of mortality or ICH. VV ECMO may be beneficial in this population.

Darbepoetin as a neuroprotective agent in mild neonatal encephalopathy: a randomized, placebo-controlled, feasibility trial

OBJECTIVE

To assess the feasibility and safety of one dose of Darbepoetin alpha (Darbe) administered to neonates ≥34 weeks with mild neonatal encephalopathy (NE).

METHODS

Randomized, masked, placebo-controlled study including neonates ≥34 weeks gestation with mild NE. Neonates were randomized to receive one dose of Darbe (10 μg/kg IV) or placebo. Clinical and laboratory maternal and newborn data were collected. The Bayley Scales of Infant and Toddler Development, third edition (Bayley-III) and a standardized neurological examination at 8-12 months of corrected age were assessed.

RESULTS

There were no differences in baseline characteristics of the 21 infants randomized (9 Darbe, 12 placebo). Adverse events were not reported at any time. Bayley-III scores were average in both Darbe and placebo groups.

CONCLUSION

This study demonstrates that a randomized, masked, placebo-controlled trial is safe and feasible. A large, randomized trial is warranted to assess the effect of Darbe in this population.

A Biomarker for Predicting Responsiveness to Stem Cell Therapy Based on Mechanism-of-Action: Evidence from Cerebral Injury

To date, no stem cell therapy has been directed to specific recipients-and, conversely, withheld from others-based on a clinical or molecular profile congruent with that cell's therapeutic mechanism-of-action (MOA) for that condition. We address this challenge preclinically with a prototypical scenario: human neural stem cells (hNSCs) against perinatal/neonatal cerebral hypoxic-ischemic injury (HII). We demonstrate that a clinically translatable magnetic resonance imaging (MRI) algorithm, hierarchical region splitting, provides a rigorous, expeditious, prospective, noninvasive "biomarker" for identifying subjects with lesions bearing a molecular profile indicative of responsiveness to hNSCs' neuroprotective MOA. Implanted hNSCs improve lesional, motor, and/or cognitive outcomes only when there is an MRI-measurable penumbra that can be forestalled from evolving into necrotic core; the core never improves. Unlike the core, a penumbra is characterized by a molecular profile associated with salvageability. Hence, only lesions characterized by penumbral > core volumes should be treated with cells, making such measurements arguably a regenerative medicine selection biomarker.

Outcomes of infants with hypoxic ischemic encephalopathy and persistent pulmonary hypertension of the newborn: results from three NICHD studies

OBJECTIVE

To determine the association of persistent pulmonary hypertension of the newborn (PPHN) with death or disability among infants with moderate or severe hypoxic ischemic encephalopathy (HIE) treated with therapeutic hypothermia.

METHODS

We compared infants with and without PPHN enrolled in the hypothermia arm from three randomized controlled trials (RCTs): Induced Hypothermia trial, "usual care" arm of Optimizing Cooling trial, and Late Hypothermia trial. Primary outcome was death or disability at 18-22 months adjusted for severity of HIE, center, and RCT.

RESULTS

Among 280 infants, 67 (24%) were diagnosed with PPHN. Among infants with and without PPHN, death or disability was 47% vs. 29% (adjusted OR: 1.65, 0.86-3.14) and death was 26% vs. 12% (adjusted OR: 2.04, 0.92-4.53), respectively.

CONCLUSIONS

PPHN in infants with moderate or severe HIE was not associated with a statistically significant increase in primary outcome. These results should be interpreted with caution given the limited sample size.

Drug delivery platforms for neonatal brain injury

Hypoxic-ischemic encephalopathy (HIE), initiated by the interruption of oxygenated blood supply to the brain, is a leading cause of death and lifelong disability in newborns. The pathogenesis of HIE involves a complex interplay of excitotoxicity, inflammation, and oxidative stress that results in acute to long term brain damage and functional impairments. Therapeutic hypothermia is the only approved treatment for HIE but has limited effectiveness for moderate to severe brain damage; thus, pharmacological intervention is explored as an adjunct therapy to hypothermia to further promote recovery. However, the limited bioavailability and the side-effects of systemic administration are factors that hinder the use of the candidate pharmacological agents. To overcome these barriers, therapeutic molecules may be packaged into nanoscale constructs to enable their delivery. Yet, the application of nanotechnology in infants is not well examined, and the neonatal brain presents unique challenges. Novel drug delivery platforms have the potential to magnify therapeutic effects in the damaged brain, mitigate side-effects associated with high systemic doses, and evade mechanisms that remove the drugs from circulation. Encouraging pre-clinical data demonstrates an attenuation of brain damage and increased structural and functional recovery. This review surveys the current progress in drug delivery for treating neonatal brain injury.

Pilot study assessing the effect of osteopathic manipulative treatment (OMT) on length of stay in neonates after therapeutic hypothermia

Context

Term neonates treated with therapeutic hypothermia (TH) may experience delays in acquiring skills for oral feeding, thus prolonging hospital admission.

Objective

To determine whether osteopathic manipulative treatment (OMT) can decrease the overall length of stay (LOS) for term neonates by accelerating the transition to full oral feeds.

Methods

A pilot study was conducted to compare LOS in term neonates treated with OMT to matched historical controls. Eligibility criteria were gestational age greater than or equal to 37 weeks, mild to moderate encephalopathy, absent seizure activity, and no brain injury on magnetic resonance imaging. Treated neonates had OMT twice between day of life four and seven, then twice per week on nonconsecutive days until hospital discharge. Secondary outcomes were to compare the number of days with nasogastric tube in both OMT and historically matched control groups and to characterize somatic dysfunction patterns in the primary affected areas of the craniosacral mechanism.

Results

Twelve of 28 neonates treated with TH between October 2017 and August 2018 met eligibility criteria for the study and were matched 3:1 to 36 historical controls. On average, mothers of neonates who received OMT were older than the historical control mothers (31.3 years [SD, ±6.0] vs. 27.4 [SD, ±4.5]; p=0.02) Nineteen of the 36 historical control neonates, but no neonates in the OMT group, were intubated for a median of two days (interquartile range 1, 4). The mean LOS in the OMT group was 9.1 vs. 11.6 days for historical controls (p=0.048); however, in a sensitivity analysis excluding intubated neonates from the historical controls, the difference was 9.1 vs. 10.1 days (p=0.21). All neonates were orally feeding at discharge. Neonates given OMT had between two and four treatments lasting 8-20 minutes. By the final treatment, the craniosacral mechanism's intraosseous and cranial base compressions and physiologic motion were improved. There were no adverse effects noted during OMT sessions.

Conclusion

Our findings suggest that OMT performed on term neonates treated with TH may decrease the amount of time needed to acquire the necessary skills for oral feeding. Although this result was not statistically significant, it may be clinically significant. A larger prospective clinical trial may have the power needed to detect a statistically significant reduction in LOS and number of days to full oral feeds in this patient population.

Cardiovascular management following hypoxic-ischemic encephalopathy in North America: need for physiologic consideration

BACKGROUND

Hypotension and hypoxemic respiratory failure are common among neonates with hypoxic-ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH). Right ventricular (RV) dysfunction is associated with adverse neurodevelopment. Individualized management utilizing targeted neonatal echocardiography (TnECHO) may enhance care.

METHODS

We evaluated the influence of TnECHO programs on cardiovascular practices in HIE/TH patients utilizing a 77-item REDCap survey. Nominated representatives of TnECHO (n = 19) or non-TnECHO (n = 96) sites were approached.

RESULTS

Seventy-one (62%) sites responded. Baseline neonatal intensive care unit characteristics and HIE volume were comparable between groups. Most centers monitor invasive blood pressure; however, we identified 17 unique definitions of hypotension. TnECHO centers were likelier to trend systolic/diastolic blood pressure and request earlier echocardiography. TnECHO responders were less likely to use fluid boluses; TnECHO responders more commonly chose an inotrope first-line, while non-TnECHO centers used a vasopressor. For HRF, TnECHO centers chose vasopressors with a favorable pulmonary vascular profile. Non-TnECHO centers used more dopamine and more extracorporeal membrane oxygen for patients with HRF.

CONCLUSIONS

Cardiovascular practices in neonates with HIE differ between centers with and without TnECHO. Consensus regarding the definition of hypotension is lacking and dopamine use is common. The merits of these practices among these patients, who frequently have comorbid pulmonary hypertension and RV dysfunction, need prospective evaluation.

IMPACT

Cardiovascular care following HIE while undergoing therapeutic hypothermia varies between centers with access to trained hemodynamics specialists and those without. Because cardiovascular dysfunction is associated with brain injury, precision medicine-based care may be an avenue to improving outcomes. Therapeutic hypothermia has introduced new physiological considerations and enhanced survival. It is essential that hemodynamic strategies evolve to keep pace; however, little literature exists. Lack of consensus regarding fundamental definitions (e.g., hypotension) highlights the importance of collaboration among the scientific community to advance the field. The value of enhanced cardiovascular care guided by hemodynamic specialists requires prospective evaluation.

Ten years since the introduction of therapeutic hypothermia in neonates with perinatal hypoxic-ischaemic encephalopathy in Spain

INTRODUCTION

More than a decade has passed since therapeutic hypothermia (TH) was introduced in Spain; this is the only neuroprotective intervention that has become standard practice in the treatment of perinatal hypoxic-ischaemic encephalopathy (HIE). This article aims to provide a current picture of the technique and to address the controversies surrounding its use.

DEVELOPMENT

In the last 10 years, TH has been successfully implemented in the vast majority of tertiary hospitals in Spain, and more than 85% of newborns with moderate or severe HIE currently receive the treatment. The factors that can improve the efficacy of TH include early treatment onset (first 6hours of life) and the control of comorbid factors associated with perinatal asphyxia. In patients with moderate HIE, treatment onset after 6hours seems to have some neuroprotective efficacy. TH duration longer than 72hours or deeper hypothermia do not offer greater neuroprotective efficacy, but instead increase the risk of adverse effects. Unclarified aspects are the sedation of patients during TH, the application of the treatment in infants with mild HIE, and its application in other scenarios. Prognostic information and time frame are one of the most challenging aspects.

CONCLUSIONS

TH is universal in countries with sufficient economic resources, although certain unresolved controversies remain. While the treatment is widespread in Spain, there is a need for cooling devices for the transfer of these patients and their centralisation.

Management of Multi Organ Dysfunction in Neonatal Encephalopathy

Neonatal Encephalopathy (NE) describes neonates with disturbed neurological function in the first post-natal days of life. NE is an overall term that does not specify the etiology of the encephalopathy although it often involves hypoxia-ischaemia. In NE, although neurological dysfunction is part of the injury and is most predictive of long-term outcome, these infants may also have multiorgan injury and compromise, which further contribute to neurological impairment and long-term morbidities. Therapeutic hypothermia (TH) is the standard of care for moderate to severe NE. Infants with NE may have co-existing immune, respiratory, endocrine, renal, hepatic, and cardiac dysfunction that require individualized management and can be impacted by TH. Non-neurological organ dysfunction not only has a negative effect on long term outcome but may also influence the efficacy of treatments in the acute phase. Post resuscitative care involves stabilization and decisions regarding TH and management of multi-organ dysfunction. This management includes detailed neurological assessment, cardio-respiratory stabilization, glycaemic and fluid control, sepsis evaluation and antibiotics, seizure identification, and monitoring and responding to biochemical and coagulation derangements. The emergence of new biomarkers of specific organ injury may have predictive value and improve the definition of organ injury and prognosis. Further evidence-based research is needed to optimize management of NE, prevent further organ dysfunction and reduce neurodevelopmental impairment.

Treatment and new progress of neonatal hypoxic-ischemic brain damage

Neonatal hypoxic ischemia (HI) results in different extents of brain damage, and immature brain tissue is particularly sensitive to the stimulation of HI. Hypoxic-ischemic brain damage (HIBD) is a common and serious nervous system disease in neonates, for both full-term infants and preterm infants, and is one of the main causes of neonatal death. The surviving infants are often associated with cerebral palsy, mental retardation, and other sequelae, which severely affect quality of life. For term infants, hypoxia and ischemia mainly affect gray matter, whereas in preterm infants, the white matter. However, up to now, inadequate standards and specific measures that can be used to treat hypoxic-ischemic brain injury are available. Recently, in addition to supportive therapy and symptomatic treatment, research on the treatment of hypoxic-ischemic brain injury has focused on the following aspects: hypothermia therapy, stem cell therapy, neuroprotective agents, ibuprofen, and combination therapy. In this review, we will summarize the treatment of HIBD and make suggestions for the future treatment direction.

Neuroprotection Strategies for Term Encephalopathy

Brain injury in the full-term and near-term neonates is a significant cause of mortality and long-term morbidity, resulting in injury patterns distinct from that seen in premature infants and older patients. Therapeutic hypothermia improves long-term outcomes for many of these infants, but there is a continued search for therapies to enhance the plasticity of the newborn brain, resulting in long-term repair. It is likely that a combination strategy utilizing both early and late interventions may have the most benefit, capitalizing on endogenous mechanisms triggered by hypoxia or ischemia. Optimizing care of these critically ill newborns in the acute setting is also vital for improving both short- and long-term outcomes.

Therapeutic hypothermia and Type II errors: Do not throw out the baby with the ice water

After initial enthusiasm for mild therapeutic hypothermia (TH) treatment after brain injuries, including global cerebral ischemia after cardiac arrest, subsequent trials suggested similar benefit using only targeted temperature management (TTM), with fewer side effects. Globally, effective treatment of brain ischemia with TH has declined. Recent data suggest, however, that TH to 33°C may be superior to TTM. We review the background and rationale underlying TH and TTM. We present previously published data from our own laboratory that confirms TH to 33°C provides superior brain cytoprotection, compared to 35°C or 37°C, over a range of delays to treatment and several durations of TH. We illustrate that the treatment effect size of either or 35 is superior to 37, but the effect size difference between 33 and 35, although significant, is small. We estimate that to demonstrate the superiority of TTM over TH, a clinical trial would need between 3,000 and 9,000 patients depending on the desired treatment effect size. Our review and our own data suggest that TH to 33°C is superior to TTM to 36°C, but an extremely large clinical trial would be needed to demonstrate the difference.

Maternal holding during therapeutic hypothermia for infants with neonatal encephalopathy is feasible

AIM

Concerns for infant destabilisation often prohibit parental holding of infants during therapeutic hypothermia (TH). We assessed the feasibility of maternal holding during TH, as the inability to hold can impede bonding.

METHODS

Vital signs were assessed in stable infants before, at two-minute intervals during and 30 minutes after a single 30-minute holding session. The infant remained on the blanket throughout holding, and both infant and blanket were placed into the mother's arms on top of a thin foam insulating barrier. Mothers and nurses were surveyed about their experience.

RESULTS

Ten infants undergoing TH for neonatal encephalopathy had no equipment malfunctions or dislodgement. The mean temperature was 33.4°C prior to and 33.5°C (p = 0.18) after holding. There was no significant bradycardia (heart rate <80 beats per minute), hypotension (mean arterial pressure <40 mm Hg) or oxygen desaturation (<93%). Nurses either strongly agreed (75%) or agreed (25%) with the statement 'After assisting with the holding protocol, I feel that holding during cooling is safe'. Mothers (100%) strongly agreed that other parents would benefit from holding.

CONCLUSION

In a small sample of ten stable infants treated with TH for neonatal encephalopathy, holding resulted in no adverse events and positive feedback from mothers and nurses.

Effect of rewarming in oxygenation and respiratory condition after neonatal exposure to moderate therapeutic hypothermia

BACKGROUND

To assess changes in clinical condition and oxygenation in neonates after rewarming following moderate therapeutic hypothermia (MTH) for neonatal encephalopathy.

METHODS

Retrospective study of 28 neonates receiving MTH in a tertiary neonatal intensive care unit in Israel. We compared pre-and 24 h post-rewarming arterial oxygen saturation (SaO₂) as measured by the blood gases analyzer, pulse-oximetry saturation (SpO₂), and cardio-respiratory condition.

RESULTS

The SpO₂ declined from 96.9% (±2.9) before rewarming to 95.2% (±2.6) after rewarming (p < 0.001). Twelve neonates (42.9%) had clinical respiratory impairment (needing higher respiratory support or had new onset desaturations). In 16 neonates (57.1%) with no change in respiratory support after rewarming, SpO₂ decreased from 98.3 ± 1.9% to 95.6 ± 3.0% (p < 0.001) and SaO₂ decreased from 97.1 ± 1.7% to 96.0 ± 2.3% (p = 0.002). The mean SpO₂ decrease was greater than mean SaO₂ decrease (2.63 ± 1.8 and 1.1 ± 1.3 respectively, p = 0.021).

CONCLUSION

Neonates who underwent MTH showed reduction in oxygenation after rewarming either by decreasing SpO₂ or increasing FiO₂ requirements. The SpO₂ decline was larger than the SaO₂ decline. We suggest careful monitoring of neonates after rewarming.

Update on the current management of newborns with neonatal encephalopathy

Hypoxic-ischemic encephalopathy is a subtype of neonatal encephalopathy and a major contributor to global neonatal morbidity and mortality. Despite advances in obstetric and neonatal care there are still challenges in accurate determination of etiology of neonatal encephalopathy. Thus, identification of intrapartum risk factors and comprehensive evaluation of the neonate is important to determine the etiology and severity of neonatal encephalopathy. In developed countries, therapeutic hypothermia as a standard of care therapy for neonates with hypoxic-ischemic encephalopathy has proven to decrease incidence of death and neurodevelopmental disabilities, including cerebral palsy in surviving children. Advances in neuroimaging, brain monitoring modalities, and biomarkers of brain injury have improved the ability to diagnose, monitor, and treat newborns with encephalopathy. However, challenges remain in early identification of neonates at risk for hypoxic-ischemic brain injury, and determination of the timing and extent of brain injury. Using imaging studies such as Neonatal MRI and MR spectroscopy have proven to be most useful in predicting outcomes in infants with encephalopathy within the first week of life, although comprehensive neurodevelopmental assessments still remains the gold standard for determining long term outcomes. Future studies are needed to identify other newborns with encephalopathy that might benefit from therapeutic hypothermia and to determine the efficacy of other adjunctive neuroprotective strategies. This review focuses on newer evidence and advances in diagnoses and management of infants with neonatal encephalopathy, including novel therapies, as well as prognostication of outcomes to childhood.

Respiratory management during therapeutic hypothermia for hypoxic-ischemic encephalopathy

Therapeutic hypothermia (TH) has become the standard of care treatment to improve morbidity and mortality in infants with hypoxic-ischemic encephalopathy (HIE). Although TH has clearly proven to be beneficial, recent studies suggest optimization of respiratory management as an approach to prevent further damage and improve neurodevelopmental outcome. The ventilatory management of asphyxiated neonates presents a challenge because both the hypoxic insult and TH have an impact on respiratory functions. Although the danger of recurrence of hypocapnia is well recognized, a brief period of severe hyperoxia also can be detrimental to the previously compromised brain and have been shown to increase the risk of adverse neurodevelopmental outcomes. Therefore, judicious ventilatory management with rigorous monitoring is of particular importance in patients with HIE. In the present review, we provide an overview of the currently available evidence on pulmonary function, respiratory morbidities, and ventilation strategies in HIE and we highlight possible future research directions.

Circulating blood cellular glucose transporters - Surrogate biomarkers for neonatal hypoxic-ischemic encephalopathy assessed by novel scoring systems

OBJECTIVE

We examined Red Blood Cell (RBC) Glucose Transporter isoform 1 (GLUT1) and White Blood Cell (WBC) Glucose Transporter isoform 3 (GLUT3) protein concentrations to assess their potential as surrogate biomarkers for the presence of hypoxic-ischemic encephalopathy (HIE) and response to therapeutic hypothermia (TH), with respect to the neurodevelopmental prognosis.

STUDY DESIGN

A prospective feasibility study of 10 infants with HIE and 8 age-matched control subjects was undertaken. Following parental consent, blood samples were obtained at baseline before institution of TH (<6 h of life), during TH, at rewarming and post-TH in the HIE group with a baseline sample from the control group. GLUT1 and GLUT3 were measured by Enzyme-linked immunosorbent assay (ELISA) with brain biomarkers, Neuron-Specific Enolase (NSE) and Glial Fibrillary Acidic Protein (GFAP). Novel "HIE-high risk" and "Neurological" scores were developed to help identify HIE and to assess severity and prognosis, respectively.

RESULTS

RBC GLUT1 concentrations were increased at the baseline pre-TH time point in HIE versus control subjects (p = .006), normalizing after TH (p = .05). An association between GLUT1 and NSE concentrations (which was reflective of the HIE-high risk and the Neuro-scores) in controls and HIE pre-TH was seen (R² = 0.36, p = .008), with GLUT1 demonstrating 90% sensitivity and 88% specificity for presence of HIE identified by Sarnat Staging. WBC GLUT3 concentrations were low and no different in HIE versus control, and GFAP concentrations trended higher during re-warming (p = .11) and post-TH (p = .16). We demonstrated a significant difference between HIE and controls for both the "HIE-high risk" and the "Neurological" Scores. The latter score revealing the severity of clinical neurological illness correlated with the corresponding RBC GLUT1 (R² value = 0.39; p = .006).

CONCLUSION

Circulating RBC GLUT1 concentrations with NSE demonstrate a significant potential in reflecting the severity of HIE pre-TH and gauging effectiveness of TH. In contrast, the low neonatal WBC GLUT3 concentrations make discerning differences between degrees of HIE as well as assessing effectiveness of TH difficult. The HIE-high risk and Neurological scores may extend the "Sarnat staging" towards assessing severity and neuro-developmental prognosis of HIE.

In-hospital outcomes of neonates with hypoxic-ischemic encephalopathy receiving extracorporeal membrane oxygenation

OBJECTIVE

To determine in-hospital outcomes of neonates with hypoxic ischemic encephalopathy (HIE) requiring extracorporeal membrane oxygenation (ECMO).

STUDY DESIGN

Single-center retrospective study from 2005 to 2016 of neonates ≥35 weeks gestation with moderate/severe HIE, requiring ECMO for persistent pulmonary hypertension of newborn (PPHN).

RESULTS

Our cohort (n = 20) received therapeutic hypothermia for moderate (n = 12), severe (n = 5), or undocumented severity (n = 3) of HIE. During ECMO, 30% (n = 6) infants developed intracranial hemorrhage at a median (IQR) duration of 24 (20) hours. Sixteen (80%) infants survived to discharge, among which 15 had MRI performed; 47% (n = 7) had normal MRI, 20% (n = 3) had intracranial hemorrhage and 13% (n = 2), 13% (n = 2) and 7% (n = 1) had NICHD stage 1, 2, and 3 pattern of brain injury respectively.

CONCLUSIONS

In this high-risk population of neonates, use of ECMO was safe and efficacious as demonstrated by survival and outcomes.

Lactate acidosis and cardiac output during initial therapeutic cooling in asphyxiated newborn infants

Aim

We hypothesized that compromised cardiac output in asphyxiated infants may influence on the rate of disappearance of lactate due to insufficient perfusion.

Methods

The study was a prospective, observational study, where infants with perinatal asphyxia who met the criteria for therapeutic hypothermia were included. Cardiac output, stroke volume and heart rate were measured by electrical velocimetry in 15 newborn infants with perinatal asphyxia during the first six hours of active therapeutic hypothermia. Results from routine blood samples were collected retrospectively. Cardiac parameters were also measured in 10 healthy, term infants after caesarian section. Cardiac parameters were compared between the asphyxiated group and the control group prior to and during hypothermia. Rate of disappearance of lactate was correlated to cardiac output in the asphyxiated infants.

Results

Cardiac output was stable in the healthy infants from 0.5 to 6 hours postnatally. The infants with perinatal asphyxia had lower cardiac output prior to and during therapeutic hypothermia compared to the control group. Rate of disappearance of lactate was not related to cardiac output.

Conclusion

An association between disappearance of lactate acidosis and low cardiac output was not confirmed. A low rate of disappearance of lactate may rather be an indicator of organ injury due to asphyxia.

Preemptive Morphine During Therapeutic Hypothermia After Neonatal Encephalopathy: A Secondary Analysis

Although therapeutic hypothermia (TH) improves outcomes after neonatal encephalopathy (NE), the safety and efficacy of preemptive opioid sedation during cooling therapy is unclear. We performed a secondary analysis of the data from a large multicountry prospective observational study (Magnetic Resonance Biomarkers in Neonatal Encephalopathy [MARBLE]) to examine the association of preemptive morphine infusion during TH on brain injury and neurodevelopmental outcomes after NE. All recruited infants had 3.0 Tesla magnetic resonance imaging and spectroscopy at 1 week, and neurodevelopmental outcome assessments at 22 months. Of 223 babies recruited to the MARBLE study, the data on sedation were available from 169 babies with moderate (n = 150) or severe NE (n = 19). Although the baseline characteristics and admission status were similar, the babies who received morphine infusion (n = 141) were more hypotensive (49% vs. 25%, p = 0.02) and had a significantly longer hospital stay (12 days vs. 9 days, p = 0.009) than those who did not (n = 28). Basal ganglia/thalamic injury (score ≥1) and cortical injury (score ≥1) was seen in 34/141 (24%) and 37/141 (26%), respectively, of the morphine group and 4/28 (14%) and 3/28 (11%) of the nonmorphine group (p > 0.05). On regression modeling adjusted for potential confounders, preemptive morphine was not associated with mean (standard deviation [SD]) thalamic N-acetylaspartate (NAA) concentration (6.9 ± 0.9 vs. 6.5 ± 1.5; p = 0.97), and median (interquartile range) lactate/NAA peak area ratios (0.16 [0.12-0.21] vs. 0.13 [0.11-0.18]; p = 0.20) at 1 week, and mean (SD) Bayley-III composite motor (92 ± 23 vs. 94 ± 10; p = 0.98), language (89 ± 22 vs. 93 ± 8; p = 0.53), and cognitive scores (95 ± 21 vs. 99 ± 13; p = 0.56) at 22 months. Adverse neurodevelopmental outcome (adjusted for severity of encephalopathy) was seen in 26 (18%) of the morphine group, and none of the nonmorphine group (p = 0.11). Preemptive morphine sedation during TH does not offer any neuroprotective benefits and may be associated with increased hospital stay. Optimal sedation during induced hypothermia requires further evaluation in clinical trials.