The prognostic value of serial EEG recordings following acute neonatal asphyxia in full-term infants

CARFS7: A guide and proforma for reading a preterm neonate's EEG

OBJECTIVES

The important role of the EEG in preterm and term babies in investigating brain function and seizures, predicting outcomes, evaluating therapeutic interventions and decision-making is being increasingly acknowledged. Development of the brain in the last trimester of pregnancy results in rapid changes in the EEG patterns in this period. Acquiring and interpreting the EEG of a preterm baby can be challenging. The aim of this study was to develop a proforma titled CARFS⁷ (Continuity, Amplitude, Reactivity, Frequency, Synchrony, Symmetry, Sleep, Sharps, Shapes, Size and Seizures) to enable neurologists to read EEGs of premature babies with greater confidence, ease and accuracy and produce a report more easily repeatable and homogenous among operators.

METHODS

The CARFS⁷proforma was developed based on a literature review and the personal experience of the authors. The parameters of the EEG evaluated and scored in the proforma are Continuity, Amplitude, Reactivity/Variability, Frequency, Synchrony, Symmetry, Sleep, Sharps, Shapes/Patterns, Size and Seizures. We also assessed the interrater reliability of the proposed scoring system incorporated in the proforma.

RESULTS

CARFS⁷ proforma incorporates a number of parameters that help evaluate the preterm EEG. The interrater reliability of the proposed scoring system in the CARFS⁷proforma was high.

CONCLUSIONS

CARFS⁷ is a user friendly proforma for reading EEGs in the preterm infant. Interrater reliability using Cohen's k shows high agreement between two child neurologists who independently rated the EEGs of 25 premature babies using this proforma. CARFS⁷ has the potential to provide, accurate, reproducible and valuable information on brain function in the preterm infant in clinical practice.

Dysmature patterns of newborn EEG recordings: Biological markers of transitory brain dysfunction or brain injury

Perinatal hypoxic-ischemic brain injury is a major cause of non-progressive neurological deficits in children. Dysmature patterns can be seen in newborns' electroencephalograms (EEGs) and may have prognostic value for long-term outcomes.

OBJECTIVE

To investigate the prognostic value of dysmature EEG patterns in term or near-term newborns.

METHODS

Neonates with dysmature patterns in their first neonatal EEG, assessed during a 6-year period from January 2010 to December 2015, were included in the study. Their outcomes at their follow-ups in June 2019 (at the age of 3 years or more) were assessed, and the presence of neurological deficits and/or epilepsy was noted.

RESULTS

We identified 347 neonates with video-EEG recordings during the observed period, in which 10 neonates had dysmature patterns in their first EEG. Eight were born at term and two were born late preterms, born at the 35 and 36-week gestational age. The reasons for admission were HIE grade I in 2 patients, grade II in 6 neonates, and heart problems in 2 patients. The second EEG was recorded at different time intervals, in 7 infants between 1 and 6 weeks; three infants had second EEG much later and were excluded from the study. Six of seven infants showed normal background activity (BA), and five had sharp waves over different regions, all six had normal developmental outcomes. One child with dysrhythmic pattern in the second EEG was diagnosed with genetic encephalopathy, developed spastic cerebral palsy and died due to severe pneumonia at the age of 6 years.

CONCLUSION

Dysmature patterns may reflect transitory brain dysfunctions. Neonatal EEG tests remain reliable and important diagnostic tool in the very first weeks of life, particularly due to the availability of sequential EEG recordings and interpretations.

Prognostic Value of Electroencephalography in Hypothermia-Treated Neonates With Hypoxic-Ischemic Encephalopathy: A Meta-Analysis

BACKGROUND

Electroencephalography (EEG) background activity is associated with neurological outcome in neonates with hypoxic-ischemic encephalopathy. There is uncertainty about the prognostic value of EEG background activity after hypothermia was introduced.

METHODS

Searches were made on Pubmed, Embase, and the Cochrane Library, from inception to March 1, 2018. Pooled sensitivities and specificities were calculated to assess the diagnostic power of burst suppression, low voltage, and flat trace background activities in the prediction of an adverse neurological outcome in the follow-up period in hypothermia-treated neonates with hypoxic-ischemic encephalopathy. I² was used to assess heterogeneity, and meta-regression was done to explore the source of heterogeneity.

RESULTS

Eighteen studies with 940 neonates were included. Pooled sensitivities and specificities in predicting the combination of death and neurodevelopmental impairment were burst suppression (sensitivity 0.87 [95% confidence interval (CI) 0.79 to 0.93], specificity 0.60 [95% CI 0.44 to 0.74]), low voltage (sensitivity 0.84 [0.75 to 0.90], specificity 0.80 [0.58 to 0.92]), and flat trace (sensitivity 0.85 [0.75 to 0.92], specificity 0.94 [0.77 to 0.99]). Subgroup analysis revealed the sensitivities of background patterns obtained after 24 hours of life were higher than those within age 24 hours, whereas the specificities were just the reverse. Flat trace performed best on sensitivity 0.93 (0.60 to 0.99) and specificity 0.90 (0.64 to 0.98) in predicting death. Burst suppression demonstrated the highest sensitivity 0.87 (0.58 to 0.97) and flat trace performed best on specificity 0.85 (0.60 to 0.96) in predicting neurodevelopmental impairment.

CONCLUSIONS

EEG background activity is predictive of long-term neurological outcome in hypothermia-treated neonates with hypoxic-ischemic encephalopathy. Burst suppression, low voltage, and flat trace are potential predictors of death or neurodevelopmental impairment.

Visual and Quantitative Electroencephalographic Analysis in Healthy Term Neonates Within the First Six Hours and the Third Day of Life

BACKGROUND

What constitutes a "normal" background electroencephalography (EEG) rhythm immediately after birth is not well understood. We performed video-electroencephalography recordings in the first six hours (first measure) and the third day of life (second measure) for evidence of transient changes in brain function.

METHODS

We performed a cohort study of an incidental sample of healthy term neonates in a single-center nursery. Main outcome measures were as follows: (1) EEG visual analysis, which included sleep-wake cycles, proportions of discontinuity and bursts with delta brushes, and number per hour of alpha/theta rolandic activity, encoches frontales, and transients; and (2) the electroencephalographic spectral analysis, which included power spectrum in the following frequency bands: delta, 0.5 to 4 Hz; theta, 4 to 8 Hz; alpha, 8 to 13 Hz; and beta, 13 to 30 Hz. Theta/delta and alpha/delta ratios were also calculated.

RESULTS

Twenty-two babies were enrolled. Significant findings (P < 0.05) in the first six hours with respect to 48 to 72 hours of life were (1) increased discontinuity, indeterminate sleep, and bursts with delta brushes; (2) higher number of transients, and lower number of alpha/theta rolandic activity and encoches frontales. Minimal changes were found in power spectrum data. However, using receiver operating characteristic curve analysis, theta/delta ratio ≤0.484 was the best cutoff to discriminate between the two measures (positive predictive value, 100.0; 95% confidence interval 71.0 to 100).

CONCLUSIONS

In healthy term neonates, immature electroencephalographic patterns, lack of clearly defined sleep-wake cycles, and frequent transients can be considered normal electroencephalographic findings in the first six hours of life. Normative power spectrum data are provided. These findings suggest that neonatal adaptation immediately after birth leads to transient changes in brain function.

Neonatal Hypoxia Ischaemia: Mechanisms, Models, and Therapeutic Challenges

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

Treatment Effects on Neonatal EEG

Conventional EEG and amplitude-integrated electroencephalography are used in neonates to assess prognosis and significant changes in brain activity. Neuroactive medications and hypothermia can influence brain activity and therefore alter EEG interpretation. There are limited studies on the effect of these therapies on neonatal EEG background activity. Medication effects on the EEG or amplitude-integrated electroencephalography include increased interburst interval duration, voltage suppression, and sleep disruption. The effect is transient in term newborns but can be persistent in premature newborns. Although therapeutic hypothermia does not produce significant changes in EEG activity, it does change the time point at which EEG can accurately predict neurodevelopmental outcome. It is important to account for these effects on the EEG to avoid inaccurate interpretation that may affect prognostication.

The Correlation Between a Short-term Conventional Electroencephalography in the First Day of Life and Brain Magnetic Resonance Imaging in Newborns Undergoing Hypothermia for Hypoxic-Ischemic Encephalopathy

OBJECTIVE

Electroencephalograph recorded in the first day of life in newborns treated with hypothermia for hypoxic-ischemic encephalopathy could be utilized as a predictive tool for the severity of brain injury on magnetic resonance imaging and mortality.

STUDY DESIGN

We analyzed newborns who were admitted for therapeutic hypothermia due to hypoxic-ischemic encephalopathy. All enrolled infants underwent encephalography within the first 24 hours of life and underwent brain magnetic resonance imaging after rewarming. All encephalographs were independently reviewed for background amplitude, continuity, and variability. Brain injury determined by magnetic resonance imaging was scored using methods described by Bonifacio et al.

RESULTS

Forty-one newborns were included in the study. Each encephalograph variable correlated significantly with the severity of injury on brain magnetic resonance imaging (P < 0.001 for each). The overall encephalograph severity estimated as mild, moderate, and severe also correlated with injury (P < 0.001). Each encephalograph variable correlated with mortality (P < 0.001 for each) and also the overall encephalograph severity (P < 0.001).

CONCLUSION

Severity of electrographic findings on encephalograph in the first day of life during therapeutic hypothermia for hypoxic-ischemic encephalopathy correlated with the extent of injury on brain magnetic resonance imaging. This information may be useful for families and aid guide clinical decision making.

Abnormal Interhemispheric Synchrony in Neonatal Hypoxic-Ischemic Encephalopathy: A Retrospective Pilot Study

BACKGROUND

Abnormal interhemispheric synchrony has been described in many clinical compromises in brain function, but its prognostic value in neonatal hypoxic-ischemic encephalopathy (HIE) is unknown.

OBJECTIVES

The study aimed at describing the frequency of abnormal interhemispheric synchrony in infants with HIE and to explore its prognostic value. The main outcome was survival without major disabilities.

METHODS

We performed a single-center retrospective cohort study and enrolled 40 neonates with HIE who underwent hypothermia.

RESULTS

Abnormal interhemispheric synchrony was observed in 23% of the patients with HIE. Sensitivity and specificity values for predicting survival without major disabilities were 90 and 67% for seizures, 50 and 97% for status epilepticus, 60 and 97% for highly abnormal EEG in the first 48 h, and 80 and 97% for EEG asynchrony, respectively. The prognostic value of asynchrony improved to 100% sensitivity, whereas specificity remained unchanged, when associated with highly abnormal EEG within the first 48 h of life.

CONCLUSIONS

Abnormal interhemispheric synchrony was observed in a quarter of the patients with HIE. This pilot study suggests that the prognostic value of asynchrony is excellent, especially when combined with EEG background analysis.

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.

EEG, evoked potentials and pulsed Doppler in asphyxiated term infants

OBJECTIVE

To evaluate electroencephalograms (EEG), evoked potentials (EPs) and Doppler findings in the cerebral arteries as predictors of a 1-year outcome in asphyxiated newborn infants.

METHODS

EEG and EPs (brain stem auditory (BAEP), somatosensory (SEP), visual (VEP) evoked potentials) were assessed in 30 asphyxiated and 30 healthy term infants during the first days (range 1-8). Cerebral blood flow velocities (CBFV) were measured from the cerebral arteries using pulsed Doppler at ∼24h of age. EEG, EPs, Doppler findings, symptoms of hypoxic ischemic encephalopathy (HIE) and their combination were evaluated in predicting a 1-year outcome.

RESULTS

An abnormal EEG background predicted poor outcome in the asphyxia group with a sensitivity of 67% and 81% specificity, and an abnormal SEP with 75% and 79%, respectively. Combining increased systolic CBFV (mean+3SD) with abnormal EEG or SEP improved the specificity, but not the sensitivity. The predictive values of abnormal BAEP and VEP were poor. Normal EEG and SEP predicted good outcome in the asphyxia group with sensitivities from 79% to 81%. The combination of normal EEG, normal SEP and systolic CBFV<3SD predicted good outcome with a sensitivity of 74% and 100% specificity.

CONCLUSIONS

Combining abnormal EEG or EPs findings with increased systolic CBFV did not improve prediction of a poor 1-year outcome of asphyxiated infants. Normal EEG and normal SEP combined with systolic CBFV<3SD at about 24 h can be valuable in the prediction of normal 1-year outcome.

SIGNIFICANCE

Combining systolic CBFV at 24 h with EEG and SEP examinations can be of use in the prediction of normal 1-year outcome among asphyxiated infants.

Cord blood proteins and multichannel-electroencephalography in hypoxic-ischemic encephalopathy

OBJECTIVE

To explore the association between multiple umbilical cord blood proteins and severity of hypoxic-ischemic encephalopathy as defined by continuous multichannel electroencephalography.

DESIGN

A prospective case-control cohort study, which was divided into separate exploratory and validation cohorts.

SETTING

A single tertiary neonatal intensive care facility.

PATIENTS

The study recruited full-term infants with perinatal asphyxia and controls. Identical procedures were used to recruit a representative exploratory sample (n = 30) and a subsequent validation cohort (n = 100).

INTERVENTION

All had umbilical cord blood drawn and biobanked at delivery, continuous multichannel electroencephalography commenced in the first 24 hours, and a modified Sarnat score assigned. Analysis of 37 potential cord blood protein markers of hypoxic-ischemic encephalopathy was performed using Luminex multiplex assays.

MEASUREMENTS AND RESULTS

Cord blood from 130 infants was analyzed. Interleukin-16 and interleukin-6 significantly differentiated between a moderate-severely abnormal and normal-mildly abnormal electroencephalography background in both exploratory (p = 0.005 and p = 0.016, respectively) and validation cohorts (p = 0.039 and p = 0.024, respectively). To develop a predictive model for a moderate-severely abnormal electroencephalography, stepwise regression analysis was used to combine these analytes with current standard clinical markers of asphyxia (pH, base deficit, and 10-min Apgar). Only Apgar score and interleukin-16 remained in the model, which was highly predictive of an abnormal electroencephalography (area under the curve [AUC] = 0.956, p < 0.001, positive predictive value = 89%, and negative predictive value = 94%).

CONCLUSIONS

Cord blood interleukin-6 and interleukin-16 were associated with electrographic grade of hypoxic-ischemic encephalopathy. To predict an abnormal electroencephalography, interleukin-16 and 10-minute Apgar used in combination performed better than current markers.

Treatment of hypoxic-ischemic encephalopathy in newborns

Hypoxic-ischemic (HI) brain injury is the most common cause of encephalopathy and seizures in term newborn infants. There is no single, valid test for birth asphyxia leading to HI brain injury, and thus this disorder is often poorly characterized, and the timing and etiology of the injury can be difficult to ascertain. Optimal management of HI brain injury involves prompt resuscitation, careful supportive care including prevention of hyperthermia and hypoglycemia, and treatment of clinical and frequent or prolonged subclinical seizures. Recent evidence suggests that therapeutic hypothermia by selective head or whole-body cooling administered within 6 hours of birth reduces the incidence of death or moderate/severe disability at 12 to 22 months. Hypothermia is a promising new therapy that physicians should consider within the context of a registry or study. Optimal seizure treatment remains controversial because the most widely used drug, phenobarbital, has limited efficacy, and the value of monitoring and treating subclinical seizures is uncertain. There is compelling need for well-designed clinical trials to address treatment of ongoing brain injury in the setting of hypoxia-ischemia and seizures. Emerging evidence from preclinical studies suggests that future therapy for HI brain injury and neonatal encephalopathy will combine novel neuroprotective and anti-seizure agents. Pilot clinical trials of newer anticonvulsants are ongoing and will provide critical information for care of neonatal seizures.

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.

Neonatal electroencephalography: review of a practical approach

Neonatal electroencephalography (EEG) recordings have routinely been performed for more than half a century. ''Old'' technical difficulties are no longer of concern with the advent of modern digital technology. Still, many ''old'' issues are at debate: characterization of neonatal EEG features, identification of EEG waveforms with potential clinical correlates, the role of neonatal EEG in prediction of neurodevelopmental outcome, and use of new devices. In the past decades, neonatal EEG and emerging issues' literature has greatly expanded. In this review, the authors have summarized some of these issues to increase the availability of the information for both clinical and research purposes. They propose an up-to-date concentrated practical approach to this rapidly expanding ''subfield'' of neonatal neurology.

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.

Bilateral loss of cortical somatosensory evoked potential at birth predicts cerebral palsy in term and near-term newborns

Bilateral loss of cortical somatosensory evoked potential (SEP) is considered the single best indicator of adverse outcome in acute encephalopathy of adult patients and older children. This study determines whether the presence or absence of the neonatal cortical SEP can predict cerebral palsy at two years in survivors of neonatal encephalopathy scored according to Sarnat criteria. We also compare SEPs with visual evoked potentials (VEPs), the EEG and neonatal neurological status. Fifty-nine neonates admitted to the neonatal intensive care unit had SEP, VEP and EEG recordings analysed according to the presence (n=37, 63%) or absence (n=22, 37%) of neonatal encephalopathy (score >or=1). Cortical SEP was always present in the perinatal period in those surviving without major neurological disability, while it was bilaterally absent in all but one patient with a subsequent diagnosis of cerebral palsy. Multivariate analysis using the logistic regression model showed that bilateral loss of cortical SEP and Sarnat Score correctly classified the neurological outcome in all patients. Bilateral absence of cortical SEP indicates early identification of neonates at risk of cerebral palsy indicating that EPs have a clinical role in the workup of neonatal encephalopathy.

Amplitude-integrated EEG is useful in predicting neurodevelopmental outcome in full-term infants with hypoxic-ischemic encephalopathy: a meta-analysis

Hypoxic ischemic encephalopathy is a common cause of neurological complications resulting in chronic handicapping conditions, such as cerebral palsy. Amplitude-integrated electroencephalography (EEG) has been used in many European countries for more than a decade in the evaluation of infants with hypoxic ischemic encephalopathy but has not been widely used in the United States. The objective of this study was to evaluate the evidence supporting use of amplitude-integrated EEG as a quantitative predictor of neurodevelopmental outcome in full-term infants with hypoxic ischemic encephalopathy. To assess efficacy, the authors performed a meta-analysis of the literature evaluating the use of the amplitude-integrated EEG or cerebral function monitor in full-term infants with hypoxic ischemic encephalopathy and their neurodevelopmental outcome. A total of 8 studies were eligible for the primary meta-analysis. There was an overall sensitivity of 91% (95% CI 87-95) and a negative likelihood ratio of 0.09 (95% CI .06-.15) for amplitude-integrated EEG tracings to accurately predict poor outcome. Amplitude-integrated EEG is a valuable bedside tool for predicting long-term neurodevelopmental outcome in term infants with hypoxic ischemic encephalopathy. This information is useful in structuring communication and care plans for physicians and parents. Early assessment techniques such as amplitude-integrated EEG provide objective means for determining inclusion in clinical studies evaluating therapies for hypoxic ischemic encephalopathy and for predicting which patients are most likely to respond to treatment.

Indications de l'électroencéphalogramme en période néonatale

The electroencephalogram (EEG), an easy-to-use and non invasive cerebral investigation, is a useful tool for diagnosis and early prognosis in newborn babies. In newborn full term babies manifesting abnormal clinical signs, EEG can point focal lesions or specific aetiology. EEG background activity and sleep organization have a high prognostic value. Tracings recorded over long period can detect seizures, with or without clinical manifestations, and differentiate them from paroxysmal non epileptic movements. The EEG should therefore be recorded at the beginning of the first symptoms, and if possible before any seizure treatment. When used as a neonatal prognostic tool, EEG background activity is classified as normal, abnormal (type A and type B discontinuous and hyperactive rapid tracing) or highly abnormal (inactive, paroxysmal, low voltage plus theta tracing). In such cases, the initial recording must be made between 12 and 48 h after birth, and then between 4 and 8 days of life. Severe EEG abnormalities before 12 h of life have no reliable prognostic value but may help in the choice of early neuroprotective treatment of acute cerebral hypoxia-ischemia. During presumed hypoxic-ischemic encephalopathy, unusual EEG patterns may indicate another diagnosis. In premature newborn babies (29-32 w GA) with neurological abnormalities, EEG use is the same as in term newborns. Without any neurological abnormal sign, EEG requirements depend on GA and the mother's or child's risk factors. Before 28 w GA, when looking for positive rolandic sharp waves (PRSW), EEG records are to be acquired systematically at D2-D3, D7-D8, 31-32 and 36 w GA. It is well known that numerous and persistent PRSW are related to periventricular leukomalacia (PVL) and indicate a bad prognosis. In babies born after 32 GA with clinically severe symptoms, an EEG should be performed before D7. Background activity, organization and maturation of the tracing are valuable diagnosis and prognosis indicators. These recommendations are designed (1) to get a maximum of precise informations from a limited number of tracings and (2) to standardize practices and thus facilitate comparisons and multicenter studies.

Prognostic significance of amplitude-integrated EEG during the first 72 hours after birth in severely asphyxiated neonates

Amplitude-integrated EEG (aEEG) is used to select patients for neuroprotective therapy after perinatal asphyxia because of its prognostic accuracy within several hours after birth. We aimed to determine the natural course of aEEG patterns during the first 72 h of life, in relation to neurologic outcome, in a group of severely asphyxiated term infants. Thirty infants, admitted to our neonatal intensive care unit from October 1998 until February 2001, were studied retrospectively. The aEEG traces obtained during the first 72 h after birth were assessed by pattern recognition: continuous normal voltage (CNV), discontinuous normal voltage (DNV), burst suppression (BS), continuous low voltage, and flat trace. Epileptic activity was also determined. The course of aEEG patterns was examined in relation to neurologic findings at 24 mo. Initially, 17 of 30 infants had severely abnormal aEEG patterns (BS or worse), which changed spontaneously to normal voltage patterns (CNV, DNV) in 7 within 48 h. The sooner the abnormalities on aEEG disappeared, the better the prognosis. The likelihood ratio of BS or worse for adverse outcome was 2.7 (95% confidence interval 1.4-5.0) between 0 and 6 h and increased to a highest value of 19 (95% confidence interval 2.8-128) between 24 and 36 h; after 48 h, it was not significant. Normal voltage patterns (CNV and DNV) up to 48 h of life were predictive for normal neurologic outcomes (negative likelihood ratios <0.3). Our findings indicate that the course of aEEG patterns adds to the prognostic value of aEEG monitoring in asphyxiated infants. Spontaneous recovery of severely abnormal aEEG patterns is not uncommon.

Neonatal intensive care neurology

The pediatric neurologist's role in the neonatal intensive care unit is described in four clinical settings: (1) assessment of outcome in neonatal encephalopathy, (2) treatment of seizures in full-term infants, (3) assessment and treatment of intraventricular hemorrhage with posthemorrhagic hydrocephalus, and (4) assessment of outcome in preterm infants. Emphasis is placed on the evidenced-based information available in these settings and on new therapies on the horizon. Using evidence-based information, the pediatric neurologist can accurately assess prognosis in the neonatal period, and this can provide the basis for a rational assessment of newer therapies in neonatal intensive care.