Continuous EEG monitoring of neonatal seizures: diagnostic and prognostic considerations

Applications of Artificial Intelligence in Neonatology

The development of artificial intelligence methods has impacted therapeutics, personalized diagnostics, drug discovery, and medical imaging. Although, in many situations, AI clinical decision-support tools may seem superior to rule-based tools, their use may result in additional challenges. Examples include the paucity of large datasets and the presence of unbalanced data (i.e., due to the low occurrence of adverse outcomes), as often seen in neonatal medicine. The most recent and impactful applications of AI in neonatal medicine are discussed in this review, highlighting future research directions relating to the neonatal population. Current AI applications tested in neonatology include tools for vital signs monitoring, disease prediction (respiratory distress syndrome, bronchopulmonary dysplasia, apnea of prematurity) and risk stratification (retinopathy of prematurity, intestinal perforation, jaundice), neurological diagnostic and prognostic support (electroencephalograms, sleep stage classification, neuroimaging), and novel image recognition technologies, which are particularly useful for prompt recognition of infections. To have these kinds of tools helping neonatologists in daily clinical practice could be something extremely revolutionary in the next future. On the other hand, it is important to recognize the limitations of AI to ensure the proper use of this technology.

Machine learning to support triage of children at risk for epileptic seizures in the pediatric intensive care unit

OBJECTIVE

Epileptic seizures are relatively common in critically-ill children admitted to the pediatric intensive care unit (PICU) and thus serve as an important target for identification and treatment. Most of these seizures have no discernible clinical manifestation but still have a significant impact on morbidity and mortality. Children that are deemed at risk for seizures within the PICU are monitored using continuous-electroencephalogram (cEEG). cEEG monitoring cost is considerable and as the number of available machines is always limited, clinicians need to resort to triaging patients according to perceived risk in order to allocate resources. This research aims to develop a computer aided tool to improve seizures risk assessment in critically-ill children, using an ubiquitously recorded signal in the PICU, namely the electrocardiogram (ECG).

APPROACH

A novel data-driven model was developed at a patient-level approach, based on features extracted from the first hour of ECG recording and the clinical data of the patient.

MAIN RESULTS

The most predictive features were the age of the patient, the brain injury as coma etiology and the QRS area. For patients without any prior clinical data, using one hour of ECG recording, the classification performance of the random forest classifier reached an area under the receiver operating characteristic curve (AUROC) score of 0.84. When combining ECG features with the patients clinical history, the AUROC reached 0.87.

SIGNIFICANCE

Taking a real clinical scenario, we estimated that our clinical decision support triage tool can improve the positive predictive value by more than 59% over the clinical standard.

Challenges and new perspectives of developmental cognitive EEG studies

Despite shared procedures with adults, electroencephalography (EEG) in early development presents many specificities that need to be considered for good quality data collection. In this paper, we provide an overview of the most representative early cognitive developmental EEG studies focusing on the specificities of this neuroimaging technique in young participants, such as attrition and artifacts. We also summarize the most representative results in developmental EEG research obtained in the time and time-frequency domains and use more advanced signal processing methods. Finally, we briefly introduce three recent standardized pipelines that will help promote replicability and comparability across experiments and ages. While this paper does not claim to be exhaustive, it aims to give a sufficiently large overview of the challenges and solutions available to conduct robust cognitive developmental EEG studies.

Neonatal Seizures and Future Epilepsy: Predictive Value of Perinatal Risk Factors, Electroencephalography, and Imaging

Context

There are limited data in the literature about the relationship between neonatal seizures and subsequent epilepsy.

Aims

This study aimed to identify the predictive value of perinatal factors, etiologies, electroencephalography (EEG), and cranial ultrasonography (USG) for future epilepsy after neonatal seizures.

Materials and Methods

A total of 92 children with epilepsy who had seizures during their neonatal period were retrospectively evaluated whether the contribution of perinatal, natal, and postnatal risk factors confining clinical, laboratory, EEG, and imaging to subsequent epilepsy. Chi-square, uni, and multivariate logistic regression were applied to find out predictive factors for subsequent epilepsy.

Results

The rate of epilepsy was 57.6 % during 1-6 years follow-up. Birth weight, Apgar scores at first and fifth minutes, resuscitation history, abnormal neurological examination, etiology, response to the treatment, abnormal EEG, or USG findings were the most important risk factors for future epilepsy in univariate analysis (P < 0.05). Furthermore, asphyxia, fifth minute Apgar scores, response to the treatment, USG, and EEG were independent predictors (P < 0.05) for subsequent epilepsy in multivariate logistic regression. No relationship was found between subsequent epilepsy and mode of delivery, seizure onset time, and seizure types (P > 0.05).

Conclusion

Although there are recent promising and advanced techniques in neonatal intensive care units, asphyxia is still one of the most important risk factors for not only poor neurological conditions but also for future epilepsy after neonatal seizures. Apgar scores, treatment with multiple antiepileptic drugs, poor background EEG activity, and abnormal neuroimaging seem to have strong predictive values for developing subsequent epilepsy. Therefore, patients with a history of neonatal seizures should be closely followed up to decrease the risk of long-term outcomes and early detection of epilepsy.

WU-NEAT: A clinically validated, open-source MATLAB toolbox for limited-channel neonatal EEG analysis

BACKGROUND

Limited-channel EEG research in neonates is hindered by lack of open, accessible analytic tools. To overcome this limitation, we have created the Washington University-Neonatal EEG Analysis Toolbox (WU-NEAT), containing two of the most commonly used tools, provided in an open-source, clinically-validated package running within MATLAB.

METHODS

The first algorithm is the amplitude-integrated EEG (aEEG), which is generated by filtering, rectifying and time-compressing the original EEG recording, with subsequent semi-logarithmic display. The second algorithm is the spectral edge frequency (SEF), calculated as the critical frequency below which a user-defined proportion of the EEG spectral power is located. The aEEG algorithm was validated by three experienced reviewers. Reviewers evaluated aEEG recordings of fourteen preterm/term infants, displayed twice in random order, once using a reference algorithm and again using the WU-NEAT aEEG algorithm. Using standard methodology, reviewers assigned a background pattern classification. Inter/intra-rater reliability was assessed. For the SEF, calculations were made using the same fourteen recordings, first with the reference and then with the WU-NEAT algorithm. Results were compared using Pearson's correlation coefficient.

RESULTS

For the aEEG algorithm, intra- and inter-rater reliability was 100% and 98%, respectively. For the SEF, the mean±SD Pearson correlation coefficient between algorithms was 0.96±0.04.

CONCLUSION

We have demonstrated a clinically-validated toolbox for generating the aEEG as well as calculating the SEF from EEG data. Open-source access will enable widespread use of common analytic algorithms which are device-independent and unlikely to become outdated as technology changes, thereby facilitating future collaborative research in neonatal EEG.

Long-term outcome in children with neonatal seizures: A tertiary center experience in cohort of 168 patients

PURPOSE

The purpose of this study was to evaluate long-term outcome and assess predictors of prognosis in children with neonatal seizures (NS).

METHOD

This retrospective study includes children with NS treated at our Institute from January the 1st 2005 until December the 31st 2015. The data were collected from medical charts and the electroencephalogram (EEG) database at the Institute. The predictive value was evaluated for following parameters: (1) characteristics of the patients, such as gender, gestational age, birth body weight, Apgar score, artificial ventilation; (2) etiology; (3) characteristics of seizures such as type, time of onset, resistance to treatment; and (4) EEG background activity and paroxysmal discharges. The outcome of NS was assessed at the end of the follow-up period and was categorized as one of the following: (1) lethal outcome, (2) neurological abnormalities, (3) intellectual disability, and (4) epilepsy. Univariate and multivariate logistic regression analyses were used to assess predictors of NS outcome.

RESULTS

The study included 168 children with NS (of which 109 are males, and 59 are females), mean aged 5.6 (SD 3.5) years at the end of the follow-up (with a range of 1 to 12 years). There was normal neurological development without epilepsy in 131 patients (78%), neurological abnormality in 31 (19.0%), intellectual disability in 28 (17.2%), epilepsy in 12 (7.4%), and lethal outcome in 7 patients (4.17%).

CONCLUSIONS

Long-term outcome in children with NS could be favorable in most patients, and it appears to be related to specific early clinical and paraclinical variables. Newborns with an abnormal background EEG activity, with seizures resistant to antiepileptic drugs and/or low Apgar score are at a higher risk of a poor outcome. Females are at a much higher risk of lethal outcome than males.

Value of electroencephalographic monitoring in newborns with hypoxic-ischemic encephalopathy treated with hypothermia

BACKGROUND

The values of electroencephalography (EEG) in neonatal hypoxic-ischemic encephalopathy (HIE) during therapeutic hypothermia (TH) are still uncertain.

AIMS

The aim of this study is to detect EEG background, the prevalence of seizures during cooling, and to determine different EEG patterns that can predict brain injury in magnetic resonance imaging (MRI).

PATIENTS AND METHODS

Thirty-nine newborns with HIE were subjected to TH. Continuous monitoring by video-EEG was carried out throughout cooling and during rewarming. MRI was done for all newborns after rewarming. The predictive value of EEG background for MRI brain injury was evaluated at 6-h intervals during cooling and rewarming.

RESULTS

At all-time intervals, normal EEG was associated with no or mild MRI brain injury. At the beginning of cooling, normal background was more predictive of a favorable MRI outcome than at later time points. After 24 h of monitoring, diffuse burst suppression and depressed patterns had the greatest prognostic value. In most patients, a discontinuous pattern was not associated with poor prognosis. Thirty-one percent developed electrical seizures, and 8% developed status epilepticus. Seizures were subclinical in 42%. There is a significant association between duration of seizure patterns detected on the EEG and severity of brain injury on MRI.

CONCLUSIONS

Continuous EEG monitoring in newborns with HIE under cooling has a prognostic value about early MRI brain injury and identifies electrographic seizures, approximately 50% of which are subclinical. Treatment of clinical and subclinical seizure results in a reduction of the total duration of seizure pattern supports the hypothesis that subclinical seizures should be treated.

Epilepsy after neonatal seizures: literature review

INTRODUCTION

Acute neonatal seizures are the most frequent neurological complication in the neonatal intensive care units and the seizing newborns have an increased risk of long-term morbidity. However, the relationship between neonatal seizures and the development of epilepsy later in life is still unclear.

METHODS

We performed a literature review using the search terms "neonatal seizures AND outcome", "neonatal seizures AND epilepsy", "neonatal seizures AND post-neonatal epilepsy", including secondary sources of data such as reference lists of articles reviewed. From the studies in which data were available, the incidence of epilepsy was calculated by dividing the number of all subjects who developed epilepsy in the different studies considered with the number of all newborns enrolled to the studies less the number of patients lost at follow-up.

RESULTS

We found 44 studies published between 1954 and 2013, of which 4 were population-based studies and the remaining were hospital-based case series. The overall population evaluated was 4538 newborns and 17.9% developed post-neonatal epilepsy, with an onset within the first year of life in 68.5% of the patients. In 80.7%, epilepsy was associated with other neurological impairments.

CONCLUSION

Estimates on epilepsy after neonatal seizures vary widely depending on selection criteria and length of the follow-up. However, it represents a common outcome of these newborns, especially in those with severe brain injury and additional neurodevelopmental disabilities.

The effects of increased fluid viscosity on stationary characteristics of EEG signal in healthy adults

Electroencephalography (EEG) systems can enable us to study cerebral activation patterns during performance of swallowing tasks and possibly infer about the nature of abnormal neurological conditions causing swallowing difficulties. While it is well known that EEG signals are non-stationary, there are still open questions regarding the stationarity of EEG during swallowing activities and how the EEG stationarity is affected by different viscosities of the fluids that are swallowed by subjects during these swallowing activities. In the present study, we investigated the EEG signal collected during swallowing tasks by collecting data from 55 healthy adults (ages 18-65). Each task involved the deliberate swallowing of boluses of fluids of different viscosities. Using time-frequency tests with surrogates, we showed that the EEG during swallowing tasks could be considered non-stationary. Furthermore, the statistical tests and linear regression showed that the parameters of fluid viscosity, sex, and different brain regions significantly influenced the index of non-stationarity values. Therefore, these parameters should be considered in future investigations which use EEG during swallowing activities.

Mapping cortical haemodynamics during neonatal seizures using diffuse optical tomography: a case study

Seizures in the newborn brain represent a major challenge to neonatal medicine. Neonatal seizures are poorly classified, under-diagnosed, difficult to treat and are associated with poor neurodevelopmental outcome. Video-EEG is the current gold-standard approach for seizure detection and monitoring. Interpreting neonatal EEG requires expertise and the impact of seizures on the developing brain remains poorly understood. In this case study we present the first ever images of the haemodynamic impact of seizures on the human infant brain, obtained using simultaneous diffuse optical tomography (DOT) and video-EEG with whole-scalp coverage. Seven discrete periods of ictal electrographic activity were observed during a 60 minute recording of an infant with hypoxic-ischaemic encephalopathy. The resulting DOT images show a remarkably consistent, high-amplitude, biphasic pattern of changes in cortical blood volume and oxygenation in response to each electrographic event. While there is spatial variation across the cortex, the dominant haemodynamic response to seizure activity consists of an initial increase in cortical blood volume prior to a large and extended decrease typically lasting several minutes. This case study demonstrates the wealth of physiologically and clinically relevant information that DOT-EEG techniques can yield. The consistency and scale of the haemodynamic responses observed here also suggest that DOT-EEG has the potential to provide improved detection of neonatal seizures.

Early electrographic seizures, brain injury, and neurodevelopmental risk in the very preterm infant

BACKGROUND

Previous studies of very preterm (VPT) infants have shown a wide range of seizure prevalence and association with intraventricular hemorrhage (IVH), white matter injury (WMI), and death. However, the impact of seizures on neurodevelopment is not well known. We hypothesized that seizures in the first 3 d after VPT birth would be associated with increased radiographic brain injury and later neurodevelopmental risk.

METHODS

For 72 h after birth, 95 VPT infants underwent amplitude-integrated electroencephalogram monitoring. High and low seizure burdens were related to radiographic brain injury, death in the neonatal period, and children's Bayley III (Bayley Scales of Infant Development) performance at 2 y corrected age in a subgroup of 59 infants.

RESULTS

The overall incidence of seizures in this sample was 48%. High seizure burden was associated with increased risk of IVH on day 1; IVH, WMI, and death on day 2; and high-grade IVH on day 3. The presence of seizures on any day was associated with decreased language performance at age 2, even after controlling for family social risk.

CONCLUSION

Seizures during the first 3 d after birth are common and are associated with an increased risk of IVH, WMI, and death. They were also associated with poorer early language development.

Continuous EEG monitoring in the neonatal intensive care unit

Continuous EEG monitoring provides an opportunity to both accurately identify seizures and monitor the neurologic status of critically ill neonates in the intensive care unit. The incidence of seizures is higher in the neonatal period than at any other time in life. Seizures and abnormalities of EEG background are associated with significant risk of mortality and long-term neurodevelopmental morbidities. In the neonatal population the majority of seizures are not clinically evident and go undetected without EEG monitoring. We review the incidence and risk factors for neonatal seizures, and the utility of continuous EEG monitoring in the neonatal intensive care unit for seizure detection and for analysis of background to allow prognostication. We consider the role of amplitude-integrated EEG in the neonatal population. We consider the utility of continuous EEG for frequently encountered neurologic indications and discuss the outcome data and some new developments in continuous EEG monitoring.

Detection of artifacts from high energy bursts in neonatal EEG

Detection of non-cerebral activities or artifacts, intermixed within the background EEG, is essential to discard them from subsequent pattern analysis. The problem is much harder in neonatal EEG, where the background EEG contains spikes, waves, and rapid fluctuations in amplitude and frequency. Existing artifact detection methods are mostly limited to detect only a subset of artifacts such as ocular, muscle or power line artifacts. Few methods integrate different modules, each for detection of one specific category of artifact. Furthermore, most of the reference approaches are implemented and tested on adult EEG recordings. Direct application of those methods on neonatal EEG causes performance deterioration, due to greater pattern variation and inherent complexity. A method for detection of a wide range of artifact categories in neonatal EEG is thus required. At the same time, the method should be specific enough to preserve the background EEG information. The current study describes a feature based classification approach to detect both repetitive (generated from ECG, EMG, pulse, respiration, etc.) and transient (generated from eye blinking, eye movement, patient movement, etc.) artifacts. It focuses on artifact detection within high energy burst patterns, instead of detecting artifacts within the complete background EEG with wide pattern variation. The objective is to find true burst patterns, which can later be used to identify the Burst-Suppression (BS) pattern, which is commonly observed during newborn seizure. Such selective artifact detection is proven to be more sensitive to artifacts and specific to bursts, compared to the existing artifact detection approaches applied on the complete background EEG. Several time domain, frequency domain, statistical features, and features generated by wavelet decomposition are analyzed to model the proposed bi-classification between burst and artifact segments. A feature selection method is also applied to select the feature subset producing highest classification accuracy. The suggested feature based classification method is executed using our recorded neonatal EEG dataset, consisting of burst and artifact segments. We obtain 78% sensitivity and 72% specificity as the accuracy measures. The accuracy obtained using the proposed method is found to be about 20% higher than that of the reference approaches. Joint use of the proposed method with our previous work on burst detection outperforms reference methods on simultaneous burst and artifact detection. As the proposed method supports detection of a wide range of artifact patterns, it can be improved to incorporate the detection of artifacts within other seizure patterns and background EEG information as well.

Outcome following neonatal seizures

Neonatal seizures are the most common manifestation of neurological disorders in the newborn period and an important determinant of outcome. Overall, for babies born at full term, mortality following seizures has improved in the last decade, typical current mortality rates being 10% (range: 7-16%), down from 33% in reports from the 1990s. By contrast, the prevalence of adverse neurodevelopmental sequelae remains relatively stable, typically 46% (range: 27-55%). The strongest predictors of outcome are the underlying cause, together with the background electroencephalographic activity. In preterm babies, for whom the outlook tends to be worse as background mortality and disability are high, seizures are frequently associated with serious underlying brain injury and therefore subsequent impairments. When attempting to define the prognosis for a baby with neonatal seizures, we propose a pathway involving history, examination, and careful consideration of all available results (ideally including brain magnetic resonance imaging) and the response to treatment before synthesizing the best estimate of risk to be conveyed to the family.

Seizures in 204 comatose children: incidence and outcome

Purpose

Seizures are common in comatose children, but may be clinically subtle or only manifest on continuous electroencephalographic monitoring (cEEG); any association with outcome remains uncertain.

Methods

cEEG (one to three channels) was performed for a median 42 h (range 2–630 h) in 204 unventilated and ventilated children aged ≤15 years (18 neonates, 61 infants) in coma with different aetiologies. Outcome at 1 month was independently determined and dichotomized for survivors into favourable (normal or moderate neurological handicap) and unfavourable (severe handicap or vegetative state).

Results

Of the 204 patients, 110 had clinical seizures (CS) before cEEG commenced. During cEEG, 74 patients (36 %, 95 % confidence interval, 95 % CI, 32–41 %) had electroencephalographic seizures (ES), the majority without clinical accompaniment (non-convulsive seizures, NCS). CS occurred before NCS in 69 of the 204 patients; 5 ventilated with NCS had no CS observed. Death (93/204; 46 %) was independently predicted by admission Paediatric Index of Mortality (PIM; adjusted odds ratio, aOR, 1.027, 95 % CI 1.012–1.042; p < 0.0005), Adelaide coma score (aOR 0.813, 95 % CI 0.700–0.943; p = 0.006), and EEG grade on admission (excess slow with >3 % fast, aOR 5.43, 95 % CI 1.90–15.6; excess slow with <3 % fast, aOR 8.71, 95 % CI 2.58–29.4; low amplitude, 10th centile <9 µV, aOR 3.78, 95 % CI 1.23–11.7; and burst suppression, aOR 10.68, 95 % CI 2.31–49.4) compared with normal cEEG, as well as absence of CS at any time (aOR 2.38, 95 % CI 1.18–4.81). Unfavourable outcome (29/111 survivors; 26 %) was independently predicted by the presence of ES (aOR 15.4, 95 % CI 4.7–49.7) and PIM (aOR 1.036, 95 % CI 1.013–1.059).

Conclusion

Seizures are common in comatose children, and are associated with an unfavourable outcome in survivors. cEEG allows the detection of subtle CS and NCS and is a prognostic tool.

The use of conventional EEG for the assessment of hypoxic ischaemic encephalopathy in the newborn: a review

Neonatal hypoxic ischaemic encephalopathy continues to be one of the leading causes of morbidity and mortality among neonates around the globe. With the advent of therapeutic hypothermia, the need to accurately classify the severity of injury in the early neonatal period is of great importance. As clinical measures cannot always accurately estimate the severity early enough for treatment to be initiated, clinicians have become more dependent on conventional and amplitude integrated EEG. Despite this, there is currently no single agreed classification scheme for the neonatal EEG in hypoxic ischaemic encephalopathy. In this review we discuss classification schemes of neonatal background EEG, published over the past 35 years, highlighting the urgent need for a universal visual analysis scheme.

Early onset epilepsy and inherited metabolic disorders: diagnosis and management

Epileptic encephalopathies presenting in early life present a diagnostic and therapeutic challenge. These disorders present with multiple seizure types that are treatment resistant and associated with significant abnormalities on electroencephalographic studies. The underlying etiology in many cases may be related to an inborn error of metabolism. Efforts to establish the specific diagnosis of a genetic defect or an inborn error of metabolism often results in requests for a vast array of biochemical and molecular tests leading to an expensive workup. In this review, we present the clinician with information that provides a rationale for a selective and nuanced approach to biochemical assays, and initial treatment strategies while waiting for a specific diagnosis to be established. A careful consideration of the presentation, identification of potentially treatable conditions, and consultation with the biochemical genetics laboratory can lead to a greater measure of success while limiting cost overruns. Such a targeted approach is hoped will lead to an early diagnosis and appropriate interventions.

Technical standards for recording and interpretation of neonatal electroencephalogram in clinical practice

Neonatal electroencephalogram (EEG), though often perceived as being difficult to record and interpret, is relatively easy to study due to the immature nature of the brain, which expresses only a few well-defined set of patterns. The EEG interpreter needs to be aware of the maturational changes as well as the effect of pathological processes and medication on brain activity. It gives valuable information for the treatment and prognostication in encephalopathic neonates. In this group, serial EEGs or EEG monitoring often gives additional information regarding deterioration/improvement of the brain function or occurrence of seizures.

Evolving understanding of hypoxic-ischemic encephalopathy in the term infant

Our aim was to document changes in the evaluation and prognosis of term-born infants with neonatal encephalopathy of hypoxic-ischemic origin, with particular reference to our own experiences and influences, and to summarize the debate on causation and the relative importance of antenatal and perinatal factors. High quality neonatal cranial ultrasound and magnetic resonance imaging and spectroscopy have enabled the accurate early visualization of different patterns of hypoxic-ischemic brain injury and prediction of their associated outcomes. Long-term follow-up shows that cognitive and memory difficulties may follow even in children without motor deficits. The very early use of electrophysiologic methods has allowed broad prognostic categorization of infants when this is not possible from clinical assessment or imaging, providing a rationale for entry into intervention trials, such as therapeutic hypothermia. This work has also shown that most of these infants have evidence of acute hypoxic-ischemic brain injury that explains their symptoms and outcomes.

A scoring system for early prognostic assessment after neonatal seizures

OBJECTIVE

The aim of this study was to devise a scoring system that could aid in predicting neurologic outcome at the onset of neonatal seizures.

METHODS

A total of 106 newborns who had neonatal seizures and were consecutively admitted to the NICU of the University of Parma from January 1999 through December 2004 were prospectively followed-up, and neurologic outcome was assessed at 24 months' postconceptional age. We conducted a retrospective analysis on this cohort to identify variables that were significantly related to adverse outcome and to develop a scoring system that could provide early prognostic indications.

RESULTS

A total of 70 (66%) of 106 infants had an adverse neurologic outcome. Six variables were identified as the most important independent risk factors for adverse outcome and were used to construct a scoring system: birth weight, Apgar score at 1 minute, neurologic examination at seizure onset, cerebral ultrasound, efficacy of anticonvulsant therapy, and presence of neonatal status epilepticus. Each variable was scored from 0 to 3 to represent the range from "normal" to "severely abnormal." A total composite score was computed by addition of the raw scores of the 6 variables. This score ranged from 0 to 12. A cutoff score of > or =4 provided the greatest sensitivity and specificity.

CONCLUSIONS

This scoring system may offer an easy, rapid, and reliable prognostic indicator of neurologic outcome after the onset of neonatal seizures. A final assessment of the validity of this score in routine clinical practice will require independent validation in other centers.

Neonatal seizures: do they damage the brain?

Seizures are an early sign of brain injury in newborns. These seizures are in most cases repetitive or associated with asymptomatic electrographic seizures. Despite the relative resistance of the immature brain to seizure-induced brain damage, there is more and more evidence that neonatal seizures impair normal brain development. This review addresses the changes associated with neonatal seizures and discusses current and future potential neuroprotective strategies.

Adjunctive levetiracetam in infants and young children with refractory partial-onset seizures

PURPOSE

To evaluate the efficacy and tolerability of adjunctive levetiracetam in very young children (aged 1 month to <4 years) with partial-onset seizures inadequately controlled with one or two antiepileptic drugs.

METHODS

This multicenter, double-blind, randomized, placebo-controlled study consisted of a 48-h inpatient baseline video-EEG (electroencephalography) and a 5-day inpatient treatment period (1-day up-titration; 48-h evaluation video-EEG in the last 2 days). Children who experienced at least two partial-onset seizures during the 48-h baseline video-EEG were randomized to either levetiracetam [40 mg/kg/day (age 1 to <6 months); 50 mg/kg/day (age >or=6 months to <4 years] or placebo.

RESULTS

Of 175 patients screened, 116 patients were randomized [60 levetiracetam; 56 placebo; intent-to-treat (ITT) population], and 111 completed the study. The responder rate in average daily partial-onset seizures frequency (48-h video-EEG monitoring; primary efficacy variable) was 43.1% for levetiracetam [modified ITT (mITT) = 58] versus 19.6% for placebo (mITT = 51; p=0.013), with odds ratio for response 3.11 [95% confidence interval (CI), 1.22-8.26]. The median percent reduction from baseline in average daily partial-onset seizure frequency was 43.6% for levetiracetam and 7.1% for placebo with a median difference between treatment groups of 39.2% (95% CI, 17.5-62.2; p < 0.001). In general, levetiracetam was well tolerated. Treatment-emergent adverse events were reported by 55.0% levetiracetam- and 44.6% placebo-treated patients (ITT population). The most frequently reported adverse events were somnolence (13.3% levetiracetam, 1.8% placebo) and irritability (11.7% levetiracetam, 0% placebo).

DISCUSSION

Adjunctive levetiracetam is an efficacious and well-tolerated treatment for partial-onset seizures in infants and young children.

Intracranial hemorrhage in term newborns: management and outcomes

Child neurology is frequently a late player in the management of the term newborn with intracranial hemorrhage in the first neonatal week. It is crucial, however, that the child neurologist undertake a comprehensive evaluation by investigating etiology and management of the hemorrhage. Intracranial hemorrhage is usually associated with premature newborns. The literature on intracranial hemorrhage in term newborns is largely in the form of isolated case reports or a small series of cases, and mostly nonsystematic. Presented here is an evidence-based review of the incidence, risk factors, etiologies, and clinical management of intracranial hemorrhage in the first week after birth, with discussion of the role of neuroimaging and hematologic investigation. Consideration of these investigations along with documentation of every intervention or its explanation will reduce parental anxiety and will assure the best possible neurologic as well as legal outcomes of term newborns with intracranial hemorrhage.

Predictive value of sequential electroencephalogram (EEG) in neonates with seizures and its relation to neurological outcome

The aim of this study was to evaluate the relationship of sequential neonatal electroencephalography (EEG) and neurological outcome in neonates with seizures to identify polysomnographic features predictive of outcome. Sequential EEGs recordings of 58 neonates that belonged to 2 historical cohorts of newborns with seizures from the same neonatal intensive care unit and who had follow-up at the Neurodevelopment Clinic of the Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS) in Porto Alegre, Brazil, were analyzed and classified into 4 groups: normal-normal, abnormal-normal, abnormal-abnormal, normal-abnormal. In patients with more than 2 recordings, during the neonatal period, the first EEG was compared with the following more abnormal. A total of 58 pairs of 2 sequential EEGs were analyzed. Considering the first EEG, a statistically significant difference was observed between the relationship of the result of this exam, if it was abnormal, with developmental delay (P = .030) and postnatal death (P = .030). Abnormal background activity was also related to neurodevelopment delay (P = .041). EEG sequences abnormal-abnormal and normal-abnormal significantly correlated to the outcome epilepsy ( P = .015). Abnormal sequential background activity was associated with neurodevelopment delay (P = .006) and epilepsy (P = .041). The burst suppression pattern when present in any EEG correlated with epilepsy (P = .013) and postnatal death (P = .034). Sequential abnormal background patterns in the first and second EEG increased the risk for epilepsy (relative risk [RR] = 1.8; 95% confidence interval [CI] = 1.03-3.0) and neurodevelopment delay (RR = 2.20; 95% CI = 1.3-3.0). Abnormal background activity only in the second electroencephalogram increased the risk for neurodevelopment delay (RR = 2.20; 95% CI = 1.3-3.0). All the neonates (n = 33) with seizures related to probable hypoxic ischemic encephalopathy had abnormalities in the first EEG (P = .030). Postnatal epilepsy was diagnosed in 24 infants (41.4%). Five (20.8%) presented West syndrome, 7 (29.2%) focal symptomatic epilepsy, 6 (25%) generalized symptomatic epilepsy, 2 (8.3%) early myoclonic encephalopathy, 1 (4.2%) early infantile epileptic encephalopathy, and in 3, the epileptic syndrome was undefined (12.5%). All infants (n = 5) with West syndrome had some degree of neurodevelopment delay. In conclusion, our findings suggest that sequential EEG in neonates with seizures has more predictive value to estimate the outcomes of neurodevelopment delay, epilepsy, and postnatal death than a single EEG recording. The abnormal background activity in even 1 EEG of the sequential recordings was more significant to determine neurological outcome than abnormal ictal activity or abnormalities in the organization of sleep state.

Continuous EEG monitoring in a paediatric intensive care unit

Monitoring with continuous EEG (cEEG) has become a valuable tool in the adult neurointensive care unit. The benefits of cEEG or amplitude-integrated EEG in neonatal intensive care have also been described. The aim of the present study was to describe and evaluate the use of cEEG in a paediatric intensive care unit. The study is a description of children and adolescents with acute neurological disorders monitored by cEEG in a paediatric intensive care unit for more than 12h. The indication for cEEG and the outcome are reported for 54 patients during a 4-year period. Twelve patients were monitored for high intracranial pressure, eight of whom died. Fourteen were monitored due to suspected, but not detected, epilepsy, their underlying diagnoses being variable. Refractory status epilepticus was the reason for cEEG in 24 cases. All of these patients survived the acute phase of status epilepticus. Four patients had seizure activity on cEEG due to global anoxia; these were not classified as status epilepticus. In conclusion, in the paediatric intensive care unit the most important indication for cEEG monitoring is in patients with suspected refractory status epilepticus where it adds to the diagnosis and choice of treatment. Continuous EEG should therefore be part of the paediatric intensive care unit technical support to select and monitor, among children with critical neurological disorders, those with refractory status epilepticus.

Reference values for amplitude-integrated electroencephalographic activity in preterm infants younger than 30 weeks' gestational age

OBJECTIVE

To prospectively investigate the development of amplitude-integrated electroencephalographic (aEEG) activity during the first 2 weeks of life in neurologically normal and clinically stable preterm infants <30 weeks' gestational age (GA).

PATIENTS AND METHODS

Infants with a GA of <30 weeks admitted to the neonatal intensive care unit of the Vienna University Children's Hospital (Vienna, Austria) were studied prospectively by using aEEG and cranial ultrasound. Clinically stable infants without clinical or sonographic evidence of neurologic abnormalities were eligible for inclusion in the reference group. The distribution of 3 background aEEG activity patterns (discontinuous low-voltage, discontinuous high-voltage, and continuous), presence of sleep-wake cycles, and number of bursts per hour in the reference group were determined by visual analysis.

RESULTS

Seventy-five infants (median GA: 27 weeks; range: 23-29 weeks) were eligible for inclusion in the reference group and had aEEG recordings during the first 2 weeks of life available. Analysis of aEEG background activity showed that with higher GA the relative amount of continuous activity increased while discontinuous patterns decreased. The number of bursts per hour decreased with increasing GA. Cyclical changes in aEEG background activity resembling early sleep-wake cycles were observed in all infants.

CONCLUSIONS

Normal values for aEEG background activity were determined in preterm infants <30 weeks' GA. Clinically stable and neurologically normal preterm infants exhibit at least 2 different patterns of aEEG activity. There is a correlation between the GA and the relative duration of continuous aEEG activity.

Phenobarbitone, neonatal seizures, and video-EEG

AIMS

To evaluate the effectiveness of phenobarbitone as an anticonvulsant in neonates.

METHODS

An observational study using video-EEG telemetry. Video-EEG was obtained before treatment was started, for an hour after treatment was given, two hours after treatment was given, and again between 12 and 24 hours after treatment was given. Patients were recruited from all babies who required phenobarbitone (20-40 mg/kg intravenously over 20 minutes) for suspected clinical seizures and had EEG monitoring one hour before and up to 24 hours after the initial dose. An EEG seizure discharge was defined as a sudden repetitive stereotyped discharge lasting for at least 10 seconds. Neonatal status epilepticus was defined as continuous seizure activity for at least 30 minutes. Seizures were categorised as EEG seizure discharges only (electrographic), or as EEG seizure discharges with accompanying clinical manifestations (electroclinical). Surviving babies were assessed at one year using the Griffiths neurodevelopmental score.

RESULTS

Fourteen babies were studied. Four responded to phenobarbitone; these had normal or moderately abnormal EEG background abnormalities and outcome was good. In the other 10 babies electrographic seizures increased after treatment, whereas electroclinical seizures reduced. Three babies were treated with second line anticonvulsants, of whom two responded. One of these had a normal neurodevelopmental score at one year, but the outcome for the remainder of the whole group was poor.

CONCLUSION

Phenobarbitone is often ineffective as a first line anticonvulsant in neonates with seizures in whom the background EEG is significantly abnormal.

Background electroencephalographic (EEG) activities of very preterm infants born at less than 27 weeks gestation: a study on the degree of continuity

AIMS

To clarify the features of the background electroencephalographic (EEG) activities in clinically well preterm infants born at less than 27 weeks gestation and to outline their chronological changes with increasing postconceptional age (PCA).

METHODS

EEGs of clinically well premature infants born at less than 27 weeks gestation were recorded during the early postnatal period. The infants were separated into three groups according to their PCA at the time of EEG recording (21-22 weeks PCA, 23-24 weeks PCA, and 25-26 weeks PCA). The mean and maximum duration of interburst intervals (IBIs), the mean duration of bursts, and the percentage of continuous and discontinuous patterns in each PCA group were evaluated.

RESULTS

There were three infants at 21-22 weeks PCA, seven at 23-24 weeks PCA, and five at 25-26 weeks PCA. Eighteen EEG recordings were obtained. The mean and maximum IBI duration decreased with increasing PCA. The percentage of continuous patterns increased with increasing PCA. Conversely, the percentage of discontinuous patterns decreased with increasing PCA.

CONCLUSIONS

In premature infants born at less than 27 weeks gestation, the characteristics of the background EEG activities were similar to those of older premature infants. These changes reflect the development of the central nervous system in this period.

Cardiovascular changes during mild therapeutic hypothermia and rewarming in infants with hypoxic-ischemic encephalopathy

BACKGROUND

Clinical trials of mild cooling to 35 degrees C or below in infants with early hypoxic-ischemic encephalopathy are under way. The objective of this study was to systematically document cardiovascular changes associated with mild therapeutic hypothermia and rewarming in such infants.

PATIENTS AND METHODS

Nine infants with gestational ages of 36 to 42 weeks, with 10-minute Apgar scores of 5 or less, clinical encephalopathy, and an abnormal electroencephalogram before 6 hours were cooled by surface cooling the trunk (n = 3) or by applying a cap perfused with cooled water (n = 6) for a median of 72 hours. The target core temperature was 34.0 degrees C to 35.0 degrees C for head-cooled infants and 33.0 degrees C to 34.0 degrees C for surface-cooled infants. Maintenance heating and rewarming were provided by an overhead heater.

RESULTS

Mean arterial blood pressure increased by a median of 10 mm Hg during cooling and fell by a median of 8 mm Hg on rewarming. Heart rate decreased by a median of 34 beats/minute on cooling and increased by a median of 32 beats/minute on rewarming. A large increase in the output of the overhead heater decreased mean arterial blood pressure in 5 infants. Anticonvulsant drugs, sedatives, or intercurrent hypoxemia also produced falls in temperature. The inspired oxygen fraction had to be increased by a median of.14 to maintain oxygenation during cooling with 2 infants requiring 100% oxygen, an effect probably attributable to pulmonary hypertension, which was reversible with rewarming.

CONCLUSIONS

Therapeutic cooling produces changes in heart rate and blood pressure that are not hazardous, but the combination of inadvertent overcooling and inappropriately rapid rewarming, together with sedative drugs that can impair normal thermoregulatory vasoconstriction, can cause hypotension in posthypoxic newborn infants. Infants who already require 50% oxygen should be cooled cautiously because pulmonary hypertension may develop. Knowledge of these cardiovascular changes, careful monitoring, anticipation, and correction should help to avoid potential adverse effects in the upcoming clinical trials.

Risk factors for neonatal encephalopathy in Kathmandu, Nepal, a developing country: unmatched case-control study

OBJECTIVE

To determine the risk factors for neonatal encephalopathy among term infants in a developing country.

DESIGN

Unmatched case-control study.

SETTING

Principal maternity hospital of Kathmandu, Nepal.

SUBJECTS

All 131 infants with neonatal encephalopathy from a population of 21 609 infants born over an 18 month period, and 635 unmatched infants systematically recruited over 12 months.

MAIN OUTCOME MEASURES

Adjusted odds ratio estimates for antepartum and intrapartum risk factors.

RESULTS

The prevalence of neonatal encephalopathy was 6.1 per 1,000 live births of which 63% were infants with moderate or severe encephalopathy. The risk of death from neonatal encephalopathy was 31%. The risk of neonatal encephalopathy increased with increasing maternal age and decreasing maternal height. Antepartum risk factors included primiparity (odds ratio 2.0) and non-attendance for antenatal care (2.1). Multiple births were at greatly increased risk (22). Intrapartum risk factors included non-cephalic presentation (3.4), prolonged rupture of membranes (3.8), and various other complications. Particulate meconium was strongly associated with encephalopathy (18). Induction of labour with oxytocin was associated with encephalopathy in 12 of 41 deliveries (5.7). Overall, 78 affected infants (60%) compared with 36 controls (6%) either had evidence of intrapartum compromise or were born after an intrapartum difficulty likely to result in fetal compromise. A concentration of maternal haemoglobin of less than 8.0 g/dl in the puerperium was significantly associated with encephalopathy (2.5) as was a maternal thyroid stimulating hormone concentration greater than 5 mIU/l (2.1).

CONCLUSIONS

Intrapartum risk factors remain important for neonatal encephalopathy in developing countries. There is some evidence of a protective effect from antenatal care. The use of oxytocin in low income countries where intrapartum monitoring is suboptimal presents a major risk to the fetus. More work is required to explore the association between maternal deficiency states and neonatal encephalopathy.

Stillbirths and neonatal encephalopathy in Kathmandu, Nepal: an estimate of the contribution of birth asphyxia to perinatal mortality in a low-income urban population

We describe a prospective cross-sectional survey over a 12-month period in the principal maternity hospital of Kathmandu, Nepal, where over 50% of the local population deliver. The study aim was to estimate the contribution of birth asphyxia to perinatal mortality in this setting. During 1995, there were 14,371 livebirths and 400 stillbirths, a total stillbirth rate of 27 per 1000 total births. The fresh term (2000 g or more) stillbirth rate was 8.5 per 1000 total births [95% CI 7.1, 10.1]. Ninety-two cases of neonatal encephalopathy (NE) affecting term infants were detected (excluding those due to congenital malformations, hypoglycaemia and early neonatal sepsis). The birth prevalence of NE was 6.4 per 1000 livebirths [95% CI 5.2, 7.8]. There was evidence of intrapartum compromise in 63 (68%) of the cases of NE and 65 (76%) of the stillbirths, but only in 12 (12%) of controls. The cause-specific early neonatal mortality rate for NE was 2.1 per 1000 livebirths [95% CI 1.4, 3.0]. Combining the NE deaths and fresh stillbirths gives an upper estimate for term birth asphyxia perinatal mortality rate of 10.8 per 1000 total births [95% CI 9.2, 12.6], 24% of all perinatal deaths before hospital discharge. This study suggests that birth asphyxia remains an important cause of perinatal mortality in developing countries. The paper discusses the pros and cons of different strategies to reduce birth asphyxia in low-income countries.

Lactate and pyruvate changes in the cerebral gray and white matter during posthypoxic seizures in newborn pigs

Cerebral lactate rises after chemically induced seizures, but it is not known if this occurs with posthypoxic seizures. We examined changes in lactate and pyruvate in gray and white matter in the newborn pig brain after a hypoxic insult known to produce seizures and permanent brain damage. Fourteen halothane-anesthetized piglets aged 24-49 h, were instrumented with a two-channel scalp EEG and microdialysis probes positioned in white and gray matter. Forty-five minutes of hypoxia were induced by reducing the fraction of inspired O2 to the maximum concentration at which EEG amplitude was < 7 microV. Postinsult EEG was classified as electroconvulsive activity (ECA) (n = 4) or burst suppression (n = 2), persistently low amplitude (n = 2), or intermittent spikes on normal background activity (n = 6). Six hours after the insult the brains were perfusion fixed for histologic probe localization. Plasma lactate and brain lactate had different time courses with brain having a persistently elevated lactate/pyruvate (L/P) ratio. The highest L/P ratios in gray and white matter were in the two pigs with persistently low amplitude EEG. There was no association between onset of electroconvulsive activity and an increase in lactate or L/P ratio. Posthypoxic energy metabolism is disturbed in both gray and white matter probably because of mitochondrial dysfunction. Seizure activity does not increase cerebral lactate or L/P ratio above the already raised levels found in posthypoxic encephalopathy. These findings cast further doubt on the hypothesis that such seizures are, in themselves, damaging.

EEG background as predictor of electrographic seizures in high-risk neonates

PURPOSE

Experience with continuous EEG monitoring in 29 consecutive infants at risk of neonatal seizures demonstrated that background abnormalities on the initial EEG were strongly associated with electrographic seizures in the subsequent 18-24 h. To test this association prospectively, we examined the relationship between EEG background and the presence of electrographic seizures in the next 22 at-risk infants monitored for seizures.

METHODS

A standard EEG was recorded for each infant at risk for seizures. Based on specific criteria, the background was graded as normal; immature for age; or mildly, moderately, or severely abnormal. The EEG was then monitored continuously until no electrographic seizures were recorded for 18-24 h.

RESULTS

Findings in the retrospective group of 29 infants and the prospective group of 22 infants did not differ. For the combined 51 infants, a normal or immature initial EEG background predicted the absence of seizures in the subsequent 18-24 h with a sensitivity of 96% [confidence interval (CI) 0.88, 1.0] and specificity of 81% (CI 0.67, 0.96). Administration of antiepileptic drugs (AEDs) before the start of the EEG recording did not affect this association.

CONCLUSIONS

In 51 consecutively monitored infants at risk for neonatal seizures, a normal or immature EEG background strongly predicted the absence of electrographic seizures in the subsequent 18-24 h; background abnormalities strongly predicted the occurrence of electrographic seizures concomitantly or in the subsequent 18-24 h of recording. Screening infants at risk for neonatal seizures with a routine EEG allows identification of infants at highest risk for seizures, thus conserving resources required for continuous EEG monitoring and facilitating early intervention for seizures.

[Emergency electroencephalography during perinatal cerebral intensive care: indications and results]

The main contribution of EEG during intensive care in infants with hypoxic-ischemic encephalopathy is i) to help determine whether infants with subtle clinical manifestations present with epileptic seizures, ii) to determine whether paralyzed or heavily sedated infants present with convulsive phenomena, iii) to assess the therapeutical response to anticonvulsants, 4) to contribute, in combination with ultrasound scanning, to diagnostic evaluation of the severity of lesions, and to provide valuable prognostic informations via the analysis of the background activity, as normal EEG is highly predictive of normal outcome, whereas various abnormal EEG features are constantly associated with subsequent major neurological abnormalities or death. These EEG features are readily available from a very early stage and may both precede and be prognostically more sensitive than information obtained from ultrasound. Recording of neonatal electroencephalogram requires awareness of the normal development of electroencephalographic features in the newborn, skilled technicians, and experienced readers of EEG tracings.

Lidocaine pharmacokinetics and toxicity in newborn pigs

In newborn infants suffering from perinatal asphyxia seizures, lidocaine (LD) has proved to be an effective anticonvulsant. At high concentrations, however, LD can itself cause convulsions. The convulsive concentration of LD (LD(conv)) varies among species. The aim of this study was to describe LD pharmacokinetics and to define the LD(conv) in awake newborn pigs. Eighteen Land race newborn pigs aged 12-60 h, weight 1.0-2.5 kg, were enrolled. LD, 2 mg/kg intravenous (IV) bolus, (n = 11) was given to estimate pharmacokinetic variables. Continuous LD infusion 2 mg x kg(-1) x min(-1) IV (n = 5) and repeated bolus doses of 15 mg/kg (n = 4) were given until electroencephalogram-confirmed seizures appeared. After the bolus injection, the elimination half-life for LD was 0.87-5.44 h. Increasing plasma concentration (LD(pl)) during infusion resulted in sedation after 5-10 min and in shivering, nystagmus, neck extension, tonic-clonic seizures at LD(conv) of 40.6 +/- 12.7 mg/L (mean +/- SD). The unbound LD(pl) at seizures was 4.4 +/- 2.4 mg/L. Younger animals convulsed at higher LD(conv) (r2 = 0.85). LD pharmacokinetics in newborn pigs were found to be dose-dependent at high plasma concentrations. At lower plasma concentrations, LD pharmacokinetics appeared to be linear. The central nervous system is the primary target for the toxic effect of LD in awake newborn pigs. LD neurotoxicity is age-dependent, and younger pigs convulse at a higher LD(conv).

Outcome of neonates with electrographically identified seizures, or at risk of seizures

A prospective study was conducted to investigate survival at 1 month and survival and developmental outcome at 1 year in a cohort of 53 neonates either suspected of or at risk of having seizures. For all patients, presence of seizures, diagnoses, and structural abnormalities were identified. If seizures were present, seizure variables were quantified. Correlations between neonatal parameters and subsequent outcome were investigated. Forty-three patients survived the first month of life. Background EEG was the only significant predictor of survival at 1 month. Three patients died after 1 month, and 2 of the three had extremely depressed interictal EEGs. Development outcome at 1 year was determined for all available surviving patients. Abnormal findings from brain imaging studies and number of independent electrographic seizure foci were correlated with some aspects of outcome at 1 year. No other correlations were identified between neonatal parameters and outcome.

A piglet survival model of posthypoxic encephalopathy

The aim of this study was to produce a neonatal piglet model which, avoiding vessel ligation, exposed the whole animal to hypoxia and produced dose-dependent clinical encephalopathy and neuropathologic damage similar to that seen after birth asphyxia. Twenty-three piglets were halothane-anesthetized. Hypoxia was induced in 19 piglets by reducing the fractional concentration of inspired oxygen (FiO2) to the maximum concentration at which the EEG amplitude was below 7 microV (low amplitude) for 17-55 min. There were transient increases in Fio2 to correct bradycardia and hypotension. Posthypoxia, the piglets were extubated when breathing was stable. Four were sham-treated controls. We aimed at 72-h survival; seven died prematurely due to posthypoxic complications. EEG and a videotaped itemized neurologic assessment were recorded regularly. We found that 95% of the animals showed neuropathologic damage. The duration of low amplitude EEG during the insult and the arterial pH at the end of the insult correlated with cortical/white matter damage; r = 0.75 and 0.81, respectively. Early postinsult EEG background amplitude (r = 0.86 at 3 h) and neurologic score (r = 0.79 at 8 h) correlated with neuropathology. Epileptic seizures in seven animals were always associated with severe neuropathologic damage. We conclude that EEG-controlled hypoxia and subsequent intensive care enabled the animals to survive with an encephalopathy which correlated with the cerebral hypoxic insult. The encephalopathy was clinically, electrophysiologically, and neuropathologically similar to that in the asphyxiated term infant. This model is suitable for examining mechanisms of damage and evaluation of potential protective therapies after birth asphyxia.

Diagnosis and treatment of epilepsy in children and adolescents

Seizures have a variety of aetiologies and may have various manifestations. Some are recurrent and represent the different types of epilepsy, whereas others are isolated events. Descriptions of various epileptic seizures, as well as their corresponding electroencephalograms (EEGs), have recently led to a unifying international classification of epileptic seizures and epilepsy syndromes. These classifications are extremely important for the practitioner working with the paediatric patient, as they allow for optimal evaluation and treatment. This article reviews the epilepsies and epilepsy syndromes with special attention to age of onset and prognosis. Special circumstances such as status epilepticus, which represents a true medical emergency, are reviewed. The first step in the pharmacological management of seizures is to establish the diagnosis of epilepsy. The recurrence of seizures (or the risk), seizure type and specific syndrome help guide initial treatment choices. There is no drug of choice, but some drugs have proven more effective for certain types of seizure. Monotherapy is preferable, and combination therapy should only be used if monotherapy with first-line drugs fails. Candidates for the newer antiepileptic drugs (e.g. felbamate, gabapentin, lamotrigine and vigabatrin) include patients resistant to older agents or who are unable to tolerate them. The exact place in therapy of these newer agents is uncertain, but in many patients they provide better seizure control and are better tolerated.

The contribution of EEG to the understanding of neonatal seizures

The neonatal EEG is a thread that has linked past and present studies of neonatal seizures that have emerged over the last several decades. Instead of experiencing a waning of value or interest, the neonatal EEG has grown in significance for characterization and quantification of seizures in the neonate. At present, it serves as the ideal theoretical end point of antiepileptic drug (AED) therapy and provides invaluable prognostic information in the analysis of its interictal EEG background. The needs of the near future are to learn the real behavior of the electrographic neonatal seizure (ENS) burden as it erupts on the scene of an acute encephalopathy. The response of the neonatal seizure burden to AED treatment requires careful quantitative description and reliable, automated ENS detection by cerebral function monitors, which are on the technologic horizon.

Serum prolactin in neonates with seizures

We studied serum prolactin (PRL) in 28 newborn infants with acute encephalopathy. Six patients had electrographically confirmed seizures. Twenty-two patients comprised the nonictal group. In the seizure group, PRL was determined at the first onset of the seizure (baseline) and at 15 and 30 min postictal. In the nonseizure group, PRL was determined at the end of the EEG and 15 min later. EEGs were visually analyzed for the presence of seizures and background abnormality (normal or mildly, moderately, or markedly abnormal). Etiologic diagnoses included congenital heart disease (12), hypoxic-ischemic encephalopathy (4), sepsis (4), respiratory distress syndrome (5) meconium aspiration (1), and metabolic disease (2). Serum PRL was significantly higher (p < 0.05) at baseline and 15 min postictally in the patients with seizures than in the nonictal group. However, PRL levels 15 and 30 min postictally were not statistically different from baseline values. Baseline PRL correlated significantly (p < 0.001) with EEG background abnormality in both groups; therefore, patients with the most abnormal EEG backgrounds had higher levels of PRL than those with a relatively normal EEG background. We conclude that newborns with EEG-confirmed seizures, particularly if seizures are not associated with clinical signs, have high baseline serum PRL levels that do not increase significantly in the immediate postictal period. Serum PRL levels correlate with the severity of the brain insult as evaluated by EEG background. Further studies are needed to enhance our understanding of the dynamics of PRL secretion in newborns with seizures and acute encephalopathy.