Treatment Duration After Acute Symptomatic Seizures in Neonates: A Multicenter Cohort Study

We aimed to define determinants of duration of treatment for acute symptomatic neonatal seizures in a contemporary multicenter observational cohort study. After adjustment for potential confounders, only study site and seizure etiology remained significantly associated with the chance of continuing antiseizure medication after discharge to home.

MRI Patterns of brain injury and neurodevelopmental outcomes in neonates with severe anaemia at birth

AIMS

To define patterns of brain injury and associated neurodevelopmental outcomes in infants with severe neonatal anaemia.

METHODS

We studied 20 infants with severe anaemia at birth (haemoglobin<7g/dL). Clinical details were analysed for causes of anaemia and co-morbidities. All had early brain magnetic resonance imaging (MRI) scans, which were reviewed for injury pattern. Neurodevelopmental outcomes were assessed at a median age of 24months.

RESULTS

The aetiology of the anaemia was feto-maternal haemorrhage in 17 and antepartum haemorrhage in 3 infants. The predominant site of injury was the white matter, which was affected in all infants, with differing grades of severity and with cystic evolution in 45%. Only one infant showed an injury pattern typical of an acute severe hypoxic-ischaemic insult. Outcomes correlated closely to the severity of MRI findings. Cerebral palsy was seen only with the most severe neuroimaging patterns (n=6). Global developmental delay, learning or behavioural problems and seizures were common with moderate injury. Visual impairment occurred, particularly with posterior injury. Microcephaly developed in 45%.

INTERPRETATION

Severe neonatal anaemia at birth was associated with a white matter predominant pattern of injury, the severity of which was related to neurodevelopmental outcomes. Early MRI and long-term follow-up are advisable following severe neonatal anaemia.

Contemporary Profile of Seizures in Neonates: A Prospective Cohort Study

OBJECTIVE

To determine the contemporary etiology, burden, and short-term outcomes of seizures in neonates monitored with continuous video-electroencephalogram (cEEG).

STUDY DESIGN

We prospectively collected data from 426 consecutive neonates (56% male, 88% term) ≤44 weeks' postmenstrual age with clinically suspected seizures and/or electrographic seizures. Subjects were assessed between January 2013 and April 2015 at 7 US tertiary care pediatric centers following the guidelines of the American Clinical Neurophysiology Society for cEEG for at-risk neonates. Seizure etiology, burden, management, and outcome were determined by chart review by the use of a case report form designed at study onset.

RESULTS

The most common seizure etiologies were hypoxic-ischemic encephalopathy (38%), ischemic stroke (18%), and intracranial hemorrhage (11%). Seizure burden was high, with 59% having ≥7 electrographic seizures and 16% having status epilepticus; 52% received ≥2 antiseizure medications. During the neonatal admission, 17% died; 49% of survivors had abnormal neurologic examination at hospital discharge. In an adjusted analysis, high seizure burden was a significant risk factor for mortality, length of hospital stay, and abnormal neurological examination at discharge.

CONCLUSIONS

In this large contemporary profile of consecutively enrolled newborns with seizures treated at centers that use cEEG per the guidelines of the American Clinical Neurophysiology Society, about one-half had high seizure burden, received ≥2 antiseizure medications, and/or died or had abnormal examination at discharge. Greater seizure burden was associated with increased morbidity and mortality. These findings underscore the importance of accurate determination of neonatal seizure frequency and etiology and a potential for improved outcome if seizure burden is reduced.

Intracranial Hemorrhage in the Neonate

Intracranial hemorrhage is a serious cause of morbidity and mortality in the neonate. Subgaleal, subdural, subarachnoid, and intraventricular hemorrhage have varying pathophysiology, but each can have serious long-term consequences. This article reviews the pathophysiology, presentation, and outcomes for intracranial hemorrhage in the newborn, as well as potential therapeutic interventions.

Impact of bilirubin-induced neurologic dysfunction on neurodevelopmental outcomes

Bilirubin-induced neurologic dysfunction (BIND) is the constellation of neurologic sequelae following milder degrees of neonatal hyperbilirubinemia than are associated with kernicterus. Clinically, BIND may manifest after the neonatal period as developmental delay, cognitive impairment, disordered executive function, and behavioral and psychiatric disorders. However, there is controversy regarding the relative contribution of neonatal hyperbilirubinemia versus other risk factors to the development of later neurodevelopmental disorders in children with BIND. In this review, we focus on the empiric data from the past 25 years regarding neurodevelopmental outcomes and BIND, including specific effects on developmental delay, cognition, speech and language development, executive function, and the neurobehavioral disorders, such as attention deficit/hyperactivity disorder and autism.

Development and validation of a seizure prediction model in critically ill children

PURPOSE

Electrographic seizures are common in encephalopathic critically ill children, but identification requires continuous EEG monitoring (CEEG). Development of a seizure prediction model would enable more efficient use of limited CEEG resources. We aimed to develop and validate a seizure prediction model for use among encephalopathic critically ill children.

METHOD

We developed a seizure prediction model using a retrospectively acquired multi-center database of children with acute encephalopathy without an epilepsy diagnosis, who underwent clinically indicated CEEG. We performed model validation using a separate prospectively acquired single center database. Predictor variables were chosen to be readily available to clinicians prior to the onset of CEEG and included: age, etiology category, clinical seizures prior to CEEG, initial EEG background category, and inter-ictal discharge category.

RESULTS

The model has fair to good discrimination ability and overall performance. At the optimal cut-off point in the validation dataset, the model has a sensitivity of 59% and a specificity of 81%. Varied cut-off points could be chosen to optimize sensitivity or specificity depending on available CEEG resources.

CONCLUSION

Despite inherent variability between centers, a model developed using multi-center CEEG data and few readily available variables could guide the use of limited CEEG resources when applied at a single center. Depending on CEEG resources, centers could choose lower cut-off points to maximize identification of all patients with seizures (but with more patients monitored) or higher cut-off points to reduce resource utilization by reducing monitoring of lower risk patients (but with failure to identify some patients with seizures).

Electrographic seizures are associated with brain injury in newborns undergoing therapeutic hypothermia

OBJECTIVE

Seizures are common among newborns with hypoxic-ischaemic encephalopathy (HIE) but the relationship between seizure burden and severity of brain injury among neonates receiving therapeutic hypothermia (TH) for HIE is unclear. We tested the hypothesis that seizure burden is associated with cerebral tissue injury independent of amplitude-integrated EEG (aEEG) background activity.

STUDY DESIGN

Term neonates undergoing 72 h of TH at four centres were selected for study if they had continuous aEEG and MRI. The aEEG with corresponding 2-channel raw EEG (aEEG/EEG), was classified by severity of background and seizure burden; MR images were classified by the severity of tissue injury.

RESULTS

Of 85 neonates, 52% had seizures on aEEG/EEG. Overall, 35% had high seizure burden, 49% had abnormal aEEG background in the first 24 h and 36% had severe injury on MRI. Seizures were most common on the first day, with significant recurrence during and after rewarming. Factors associated with severe injury on MRI were high seizure burden, poor aEEG background, 10 min Apgar and the need for more than one anticonvulsant. In multivariate logistic regression, high seizure burden was independently associated with greater injury on MRI (OR 5.00, 95% CI 1.47 to 17.05 p=0.01). Neither aEEG background, nor 10 min Apgar score were significant.

CONCLUSIONS

Electrographic seizure burden is associated with severity of brain injury on MRI in newborns with HIE undergoing TH, independent of degree of abnormality on aEEG background. Seizures are common during cooling, particularly on day 1, with a significant rebound on day 4.

Risk factors for EEG seizures in neonates treated with hypothermia: a multicenter cohort study

OBJECTIVE

To assess the risk factors for electrographic seizures among neonates treated with therapeutic hypothermia for hypoxic-ischemic encephalopathy (HIE).

METHODS

Three-center observational cohort study of 90 term neonates treated with hypothermia, monitored with continuous video-EEG (cEEG) within the first day of life (median age at onset of recording 9.5 hours, interquartile range 6.3-14.5), and continued for >24 hours (total recording 93.3 hours, interquartile range 80.1-112.8 among survivors). A pediatric electroencephalographer at each site reviewed cEEGs for electrographic seizures and initial EEG background category.

RESULTS

A total of 43 (48%) had electrographic seizures, including 9 (10%) with electrographic status epilepticus. Abnormal initial EEG background classification (excessively discontinuous, depressed and undifferentiated, burst suppression, or extremely low voltage), but not clinical variables (including pH <6.8, base excess ≤-20, or 10-minute Apgar ≤ 3), was strongly associated with seizures.

CONCLUSIONS

Electrographic seizures are common among neonates with HIE undergoing hypothermia and are difficult to predict based on clinical features. These results justify the recommendation for cEEG monitoring in neonates treated with hypothermia.

Electrographic seizures and status epilepticus in critically ill children and neonates with encephalopathy

Electrographic seizures are seizures that are evident on EEG monitoring. They are common in critically ill children and neonates with acute encephalopathy. Most electrographic seizures have no associated clinical changes, and continuous EEG monitoring is necessary for identification. The effect of electrographic seizures on outcome is the focus of active investigation. Studies have shown that a high burden of electrographic seizures is associated with worsened clinical outcome after adjustment for cause and severity of brain injury, suggesting that a high burden of such seizures might independently contribute to secondary brain injury. Further research is needed to determine whether identification and management of electrographic seizures reduces secondary brain injury and improves outcome in critically ill children and neonates.

Amplitude-integrated electro-encephalography: the child neurologist's perspective

Neurologists increasingly recognize that critically ill patients are at high risk for seizures, particularly nonconvulsive seizures, and that neuromonitoring is a useful tool for diagnosing seizures and assessing brain function in these patients. Amplitude-integrated electroencephalography (EEG) is a simplified bedside neurophysiology tool that has become widely used in neonates over the past decade. Despite widespread interest by both neurologists and neonatologists in continuous brain monitoring, amplitude-integrated EEG has been largely ignored by neurologists, forcing neonatologists to "go it alone" when interpreting data from this bedside tool. Although amplitude-integrated EEG cannot replace conventional EEG for background monitoring and detection of seizures, it remains a useful instrument that complements conventional EEG, is being widely adopted by neonatologists, and should be supported by neonatal neurologists.

Antepartum and intrapartum factors preceding neonatal hypoxic-ischemic encephalopathy

OBJECTIVE

To determine whether antepartum factors alone, intrapartum factors alone, or both in combination, are associated with term neonatal hypoxic-ischemic encephalopathy (HIE).

METHODS

A total of 405 infants ≥ 35 weeks' gestation with early encephalopathy, born between 1992 and 2007, were compared with 239 neurologically normal infants born between 1996 and 1997. All cases met criteria for perinatal asphyxia, had neuroimaging findings consistent with acute hypoxia-ischemia, and had no evidence for a non-hypoxic-ischemic cause of their encephalopathy.

RESULTS

Both antepartum and intrapartum factors were associated with the development of HIE on univariate analysis. Case infants were more often delivered by emergency cesarean delivery (CD; 50% vs 11%, P < .001) and none was delivered by elective CD (vs 10% of controls). On logistic regression analysis only 1 antepartum factor (gestation ≥ 41 weeks) and 7 intrapartum factors (prolonged membrane rupture, abnormal cardiotocography, thick meconium, sentinel event, shoulder dystocia, tight nuchal cord, failed vacuum) remained independently associated with HIE (area under the curve 0.88; confidence interval 0.85-0.91; P < .001). Overall, 6.7% of cases and 43.5% of controls had only antepartum factors; 20% of cases and 5.8% of controls had only intrapartum factors; 69.5% of cases and 31% of controls had antepartum and intrapartum factors; and 3.7% of cases and 19.7% of controls had no identifiable risk factors (P < .001).

CONCLUSIONS

Our results do not support the hypothesis that HIE is attributable to antepartum factors alone, but they strongly point to the intrapartum period as the necessary factor in the development of this condition.

How to use: the neonatal neurological examination

The neurological exam can be a challenging part of a newborn's full evaluation. At the same time, the neonatal neurological exam is a useful tool in identifying babies needing closer evaluation for potential problems. The Dubowitz assessment is a standardised approach to the neonatal neurological exam designed for use by paediatricians in routine practice. Evidence has validated this technique and delineated its utility as a screening exam in various populations. This paper reviews clinical application of the Dubowitz assessment of the newborn.

Genetic testing in children with epilepsy

Genetic testing is now available clinically for several epilepsies. Neurologists increasingly face decisions about diagnostic testing in affected patients and should carefully deliberate the ethical considerations associated with genetic testing. The merits of ordering a genetic test are largely based on the utility for guiding clinical care, providing a prognosis, estimating recurrence risk, and identifying comorbidities. At the same time, a decision to pursue any genetic testing also requires evaluation of associated ethical concerns. This case illustrates ethical challenges that arise when considering genetic testing for a pediatric patient with epilepsy.

White matter and cortical injury in hypoxic-ischemic encephalopathy: antecedent factors and 2-year outcome

OBJECTIVE

To examine the spectrum of isolated white matter (WM)/cortical injury and its relation to outcomes in infants with hypoxic-ischemic encephalopathy (HIE) and normal appearing basal ganglia and thalami.

STUDY DESIGN

From 1992-2007, 84 term infants with HIE and normal basal ganglia and thalami on neonatal magnetic resonance imaging were studied; WM/cortical lesions were classified by site and severity. Neurodevelopmental outcomes and head growth were documented at a median age of 2 years.

RESULTS

The WM was normal or mildly abnormal in 33.5%, moderate in 40.5%, and severely abnormal in 26% of infants. Cortical involvement was not seen or was only mild in 75.5%, moderate in 13%, and severe in 12% of infants. WM and cortical injury severity were highly correlated (Spearman ρ = 0.74; P < .001). Infants with severe WM injury had more severe neonatal courses and a higher incidence of hypoglycemia. No infant died. Five infants (6%) developed cerebral palsy but all could walk independently. Cognitive, visual, language, behavioral, and seizure problems were highly prevalent and correlated significantly with the severity of WM injury and poor postnatal head growth.

CONCLUSION

Infants with HIE and selective WM/cortical injury have a low prevalence of cerebral palsy but have a wide range of other problems, which occur more often with severe WM/cortical lesions.

Modified Pediatric ASPECTS Correlates with Infarct Volume in Childhood Arterial Ischemic Stroke

Background and Purpose: Larger infarct volume as a percent of supratentorial brain volume (SBV) predicts poor outcome and hemorrhagic transformation in childhood arterial ischemic stroke (AIS). In perinatal AIS, higher scores on a modified pediatric version of the Alberta Stroke Program Early CT Score using acute MRI (modASPECTS) predict later seizure occurrence. The objectives were to establish the relationship of modASPECTS to infarct volume in perinatal and childhood AIS and to establish the interrater reliability of the score. Methods: We performed a cross sectional study of 31 neonates and 40 children identified from a tertiary care center stroke registry with supratentorial AIS and acute MRI with diffusion weighted imaging (DWI) and T2 axial sequences. Infarct volume was expressed as a percent of SBV using computer-assisted manual segmentation tracings. ModASPECTS was performed on DWI by three independent raters. The modASPECTS were compared among raters and to infarct volume as a percent of SBV. Results: ModASPECTS correlated well with infarct volume. Spearman rank correlation coefficients (ρ) for the perinatal and childhood groups were 0.76, p < 0.001 and 0.69, p < 0.001, respectively. Excluding one perinatal and two childhood subjects with multifocal punctate ischemia without large or medium sized vessel stroke, ρ for the perinatal and childhood groups were 0.87, p < 0.001 and 0.80, p < 0.001, respectively. The intraclass correlation coefficients for the three raters for the neonates and children were 0.93 [95% confidence interval (CI) 0.89–0.97, p < 0.001] and 0.94 (95% CI 0.91–0.97, p < 0.001), respectively. Conclusion: The modified pediatric ASPECTS on acute MRI can be used to estimate infarct volume as a percent of SBV with a high degree of validity and interrater reliability.

Risk of later seizure after perinatal arterial ischemic stroke: a prospective cohort study

OBJECTIVE

Although acute seizures are common among neonates with arterial ischemic stroke (AIS), the incidence of subsequent seizures is unknown. The goals of this study were to determine the incidence of seizures following hospital discharge after perinatal acute AIS, and to assess lesion characteristics associated with later seizure occurrence.

METHODS

Neonates with confirmed acute AIS on MRI were identified through a prospective stroke registry. Clinic visits and telephone follow-up identified occurrence of seizures after hospital discharge. MRI scans were graded for size and characteristics of infarct, and associations with seizures after stroke were analyzed.

RESULTS

At a mean (SD) follow-up of 31.3 (16.1) months, 11 of 46 (23.9%) patients with perinatal AIS had at least 1 seizure. Five patients had a single episode of seizure, and 6 developed epilepsy. The Kaplan-Meier probability of remaining seizure-free at 3 years was 73%. Stroke size on MRI was significantly associated with development of later seizures, with an incidence rate of later seizures 6.2 times higher among those with larger stroke size.

CONCLUSIONS

Seizures occurred in <25% of patients during initial follow-up after perinatal AIS. Of those with seizures, nearly half had a single episode of seizure and not early epilepsy. Larger stroke size was associated with higher risk of seizure. These data suggest that prolonged treatment with anticonvulsant agents may not be indicated for seizure prophylaxis after perinatal AIS. These findings may help guide clinicians in counseling families and could form the basis for much-needed future research in this area.

Electrographic seizures during therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy

Electrographic seizures are common in neonates with hypoxic-ischemic encephalopathy, but detailed data are not available regarding seizure incidence during therapeutic hypothermia. The objective of this prospective study was to determine the incidence and timing of electrographic seizures in term neonates undergoing whole-body therapeutic hypothermia for hypoxic-ischemic encephalopathy as detected by conventional full-array electroencephalography for 72 hours of therapeutic hypothermia and 24 hours of normothermia. Clinical and electroencephalography data were collected from 26 consecutive neonates. Electroencephalograms were reviewed by 2 pediatric neurophysiologists. Electrographic seizures occurred in 17 of 26 (65%) patients. Seizures were entirely nonconvulsive in 8 of 17 (47%), status epilepticus occurred in 4 of 17 (23%), and seizure onset was in the first 48 hours in 13 of 17 (76%) patients. Electrographic seizures were common, were often nonconvulsive, and had onset over a broad range of times in the first days of life.

Management of common neurologic symptoms in pediatric palliative care: seizures, agitation, and spasticity

Palliative care for children is complex and focuses on patients' comfort. Some of the most troublesome symptoms as patients approach the end of life are seizures, agitation, and spasticity. Many doctors caring for children at the end of life are uncomfortable or untrained in managing these symptoms in children. Our goal is to help physicians recognize and treat these neurologic symptoms optimally.

Differences in pediatric oncologists' estimates of curability and treatment recommendations for patients with advanced cancer

BACKGROUND

When goals of therapy for children with advanced cancer are called into question, physician recommendations regarding treatment goals have been shown to be important for families. However, there has been no demonstration of the degree of variation between pediatric oncologists' recommendations in such situations.

PROCEDURE

We provided 48 pediatric oncologists with two identical case histories and identical prognostic data from the literature. Individual interviews were then performed to assess variation in (1) recommended treatment goal, (2) perceived chances for cure, and (3) degree to which further curative intervention would be considered desirable for each patient.

RESULTS

There was a large variability in each of the areas examined. For both patients, there was wide divergence (2:1 and 2:3) in whether to recommend cure as the goal of treatment. There were also differences in physician estimates for likelihood of cure for each patient. Finally, even among those with identical estimates for likelihood of cure, there were differences in the treatment goals physicians would recommend and how strongly they would counsel for them.

CONCLUSIONS

This study demonstrates that even with identical clinical data and prognostic evidence from the literature, pediatric oncologists vary widely in their recommendations regarding goals of treatment for children with advanced cancer.

Numerical subtraction in the pigeon: evidence for a linear subjective number scale

When humans and animals compare two numbers, responding is faster and more accurate with increasing numerical disparity and decreasing numerical size. Researchers explaining these distance and size effects often, assume that the subjective number continuum is logarithmically compressed. An alternative hypothesis is that the subjective number continuum is linear, but positions farther along it are proportionately fuzzier, that is, less precisely located. These two hypotheses have been treated as functionally equivalent because of their similar empirical predictions. The current experiment sought to resolve this issue with a paradigm originally developed to address the subjective representation of time (time left). In our adaptation, pigeons were required to compare a constant number with the number remaining after a numerical subtraction. Our results indicate that subjective number is linearly, not logarithmically, related to objective number.