Clinical management of seizures in newborns : diagnosis and treatment

A Review of the Prevalence, Etiology, Diagnosis, and Management of Pediatric Epilepsies in India

Pediatric seizures are one of the most common neurological manifestations seen in pediatrics. Unravelling the etiology, timely and appropriate investigations followed by suitable therapies are essential for improving quality of life. During the pandemic, focused group discussions were conducted among 50 pediatric neurologists across five cities in India to gather insights on treatment practices in pediatric epilepsy and to optimize therapeutic strategies and alternative approaches for rational use of antiepileptic medications. These discussions were mainly aimed at reviewing current literature on prevalence, etiology, diagnosis, and management of epilepsy in children and subsequently rationalizing diagnostic and treatment approaches in routine clinical practice. Epileptic encephalopathies comprise of childhood epilepsy with progressive cerebral dysfunction. Genomics plays a vital role in identifying the underlying genetic associations, empowering precision therapy. Currently, the ketogenic diet has become a well-recognized modality for reducing severity of seizures. To overcome the high incidence of adverse effects due to older antiepileptic drugs, newer drugs are being developed to improve ease of use, diminish drug interactions, decrease adverse effects, and identify drugs with unique mechanisms of action. Common lacunae in practice include information gaps, educating parents, or caregivers about rational drug use and ensuring compliance to antiepileptic medications. This article discussed the consensus clinical viewpoint of expert clinicians, as well as insights on optimized treatment of pediatric epilepsies in both infancy and childhood. It also discusses aspects, like reducing drug burden, emerging therapies in the identification of the genetic basis of epilepsies, and targeted therapy alternatives, for pediatric populations in the Indian scenario.

Effect of Treatment of Clinical Seizures vs Electrographic Seizures in Full-Term and Near-Term Neonates: A Randomized Clinical Trial

IMPORTANCE

Seizures in the neonatal period are associated with increased mortality and morbidity. Bedside amplitude-integrated electroencephalography (aEEG) has facilitated the detection of electrographic seizures; however, whether these seizures should be treated remains uncertain.

OBJECTIVE

To determine if the active management of electrographic and clinical seizures in encephalopathic term or near-term neonates improves survival free of severe disability at 2 years of age compared with only treating clinically detected seizures.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was conducted in tertiary newborn intensive care units recruited from 2012 to 2016 and followed up until 2 years of age. Participants included neonates with encephalopathy at 35 weeks' gestation or more and younger than 48 hours old. Data analysis was completed in April 2021.

INTERVENTIONS

Randomization was to an electrographic seizure group (ESG) in which seizures detected on aEEG were treated in addition to clinical seizures or a clinical seizure group (CSG) in which only seizures detected clinically were treated.

MAIN OUTCOMES AND MEASURES

Primary outcome was death or severe disability at 2 years, defined as scores in any developmental domain more than 2 SD below the Australian mean assessed with Bayley Scales of Neonate and Toddler Development, 3rd ed (BSID-III), or the presence of cerebral palsy, blindness, or deafness. Secondary outcomes included magnetic resonance imaging brain injury score at 5 to 14 days, time to full suck feeds, and individual domain scores on BSID-III at 2 years.

RESULTS

Of 212 randomized neonates, the mean (SD) gestational age was 39.2 (1.7) weeks and 122 (58%) were male; 152 (72%) had moderate to severe hypoxic-ischemic encephalopathy (HIE) and 147 (84%) had electrographic seizures. A total of 86 neonates were included in the ESG group and 86 were included in the CSG group. Ten of 86 (9%) neonates in the ESG and 4 of 86 (4%) in the CSG died before the 2-year assessment. The odds of the primary outcome were not significantly different in the ESG group compared with the CSG group (ESG, 38 of 86 [44%] vs CSG, 27 of 86 [31%]; odds ratio [OR], 1.83; 95% CI, 0.96 to 3.49; P = .14). There was also no significant difference in those with HIE (OR, 1.77; 95% CI, 0.84 to 3.73; P = .26). There was evidence that cognitive outcomes were worse in the ESG (mean [SD] scores, ESG: 97.4 [17.7] vs CSG: 103.8 [17.3]; mean difference, -6.5 [95% CI, -1.2 to -11.8]; P = .01). There was little evidence of a difference in secondary outcomes, including time to suck feeds, seizure burden, or brain injury score.

CONCLUSIONS AND RELEVANCE

Treating electrographic and clinical seizures with currently used anticonvulsants did not significantly reduce the rate of death or disability at 2 years in a heterogeneous group of neonates with seizures.

TRIAL REGISTRATION

http://anzctr.org.au Identifier: ACTRN12611000327987.

Liquid chromatographic methods for determination of the new antiepileptic drugs stiripentol, retigabine, rufinamide and perampanel: A comprehensive and critical review

The new antiepileptic drugs perampanel, retigabine, rufinamide and stiripentol have been recently approved for different epilepsy types. Being them an innovation in the antiepileptics armamentarium, a lot of investigations regarding their pharmacological properties are yet to be performed. Besides, considering their broad anticonvulsant activities, an extension of their therapeutic indications may be worthy of investigation, especially regarding other seizure types as well as other central nervous system disorders. Although different liquid chromatographic (LC) methods coupled with ultraviolet, fluorescence, mass or tandem-mass spectrometry detection have already been developed for the determination of perampanel, retigabine, rufinamide and stiripentol, new and more cost-effective methods are yet required. Therefore, this review summarizes the main analytical aspects regarding the liquid chromatographic methods developed for the analysis of perampanel, retigabine (and its main active metabolite), rufinamide and stiripentol in biological samples and pharmaceutical dosage forms. Furthermore, the physicochemical and stability properties of the target compounds will also be addressed. Thus, this review gathers, for the first time, important background information on LC methods that have been developed and applied for the determination of perampanel, retigabine, rufinamide and stiripentol, which should be considered as a starting point if new (bio)analytical techniques are aimed to be implemented for these drugs.

Management of seizures in neonates with neonatal encephalopathy treated with hypothermia

Neonatal encephalopathy (NE) is the most common etiology of acute neonatal seizures - about half of neonates treated with therapeutic hypothermia for NE have EEG-confirmed seizures. These seizures are best identified with continuous EEG monitoring, as clinical diagnosis leads to under-diagnosis of subclinical seizures and over-treatment of events that are not seizures. High seizure burden, especially status epilepticus, is thought to augment brain injury. Treatment, therefore, is aimed at minimizing seizure burden. Phenobarbital remains the mainstay of treatment, as it is more effective than levetiracetam and easier to administer than fosphenytoin. Emerging evidence suggests that, for many neonates, it is safe to discontinue the phenobarbital after acute seizures resolve and prior to hospital discharge.

Neonatal Epileptic Encephalopathies

The majority of neonatal seizures are related to common diagnoses, including hypoxic-ischemic encephalopathy and intraventricular hemorrhage. While relatively uncommon, neonatal epileptic encephalopathies represent an important group of neonatal seizure disorders that require immediate diagnosis and intervention. In this review, we provide a summary of the benign and severe neonatal epilepsy syndromes. While benign epilepsy syndromes have favorable prognoses, rapid and accurate diagnosis may prevent an unnecessarily long course of antiseizure medications. The severe epilepsy syndromes may be related to a number of underlying genetic disorders and often carry a poor prognosis. Herein we review diagnostic and therapeutic strategies, and provide a set or algorithms for said purposes.

Neonatal Seizures Revisited

Seizures are the most common neurological disorder in newborns and are most prevalent in the neonatal period. They are mostly caused by severe disorders of the central nervous system (CNS). However, they can also be a sign of the immaturity of the infant’s brain, which is characterized by the presence of specific factors that increase excitation and reduce inhibition. The most common disorders which result in acute brain damage and can manifest as seizures in neonates include hypoxic-ischemic encephalopathy (HIE), ischemic stroke, intracranial hemorrhage, infections of the CNS as well as electrolyte and biochemical disturbances. The therapeutic management of neonates and the prognosis are different depending on the etiology of the disorders that cause seizures which can lead to death or disability. Therefore, establishing a prompt diagnosis and implementing appropriate treatment are significant, as they can limit adverse long-term effects and improve outcomes. In this review paper, we present the latest reports on the etiology, pathomechanism, clinical symptoms and guidelines for the management of neonates with acute symptomatic seizures.

Efficacy of Fosphenytoin as First-Line Antiseizure Medication for Neonatal Seizures Compared to Phenobarbital

Currently used treatment protocols for neonatal seizures vary among centers with limited evidence to support the choice of a given antiseizure medication. Because of concerns about the potential negative impact of phenobarbital on long-term neurodevelopment outcomes, our unit transitioned to fosphenytoin as the first-line antiseizure medication. A retrospective observational cohort study was conducted to compare the acute and long-term outcomes of fosphenytoin and phenobarbital as first-line antiseizure medication for neonatal seizure treatment. The 2 study groups had similar baseline characteristics for neonatal variables as well as maternal antenatal complications. We did not find any differences in the acute outcomes between the 2 groups. However, significantly fewer infants in the fosphenytoin group had moderate-to-severe neurodevelopmental delay at the 18- and 24-month assessments. In conclusion, although both medications were equally efficacious for acute neonatal seizure control, fosphenytoin had the potential for significantly better neurodevelopmental outcomes at 18-24 months of age.

Sex specific correlation between GABAergic disruption in the dorsal hippocampus and flurothyl seizure susceptibility after neonatal hypoxic-ischemic brain injury

Since neonatal hypoxia-ischemia (HI) disrupts the hippocampal (Hp) GABAergic network in the mouse and Hp injury in this model correlates with flurothyl seizure susceptibility only in male mice, we hypothesized that GABAergic disruption correlates with flurothyl seizure susceptibility in a sex-specific manner. C57BL6 mice were exposed to HI (Vannucci model) versus sham procedures at P10, randomized to normothermia (NT) or therapeutic hypothermia (TH), and subsequently underwent flurothyl seizure testing at P18. Only in male mice, Hp atrophy correlated with seizure susceptibility. The number of Hp parvalbumin positive interneurons (PV⁺INs) decreased after HI in both sexes, but TH attenuated this deficit only in females. In males only, seizure susceptibility directly correlated with the number of PV⁺INs, but not somatostatin or calretinin expressing INs. Hp GABA_B receptor subunit levels were decreased after HI, but unrelated to later seizure susceptibility. In contrast, Hp GABA_A receptor α1 subunit (GABA_ARα1) levels were increased after HI. Adjusting the number of PV⁺ INs for their GABA_ARα1 expression strengthened the correlation with seizure susceptibility in male mice. Thus, we identified a novel Hp sex-specific GABA-mediated mechanism of compensation after HI that correlates with flurothyl seizure susceptibility warranting further study to better understand potential clinical translation.

Can an mhealth clinical decision-making support system improve adherence to neonatal healthcare protocols in a low-resource setting?

BACKGROUND

This study assessed health workers' adherence to neonatal health protocols before and during the implementation of a mobile health (mHealth) clinical decision-making support system (mCDMSS) that sought to bridge access to neonatal health protocol gap in a low-resource setting.

METHODS

We performed a cross-sectional document review within two purposively selected clusters (one poorly-resourced and one well-resourced), from each arm of a cluster-randomized trial at two different time points: before and during the trial. The total trial consisted of 16 clusters randomized into 8 intervention and 8 control clusters to assess the impact of an mCDMSS on neonatal mortality in Ghana. We evaluated health workers' adherence (expressed as percentages) to birth asphyxia, neonatal jaundice and cord sepsis protocols by reviewing medical records of neonatal in-patients using a checklist. Differences in adherence to neonatal health protocols within and between the study arms were assessed using Wilcoxon rank-sum and permutation tests for each morbidity type. In addition, we tracked concurrent neonatal health improvement activities in the clusters during the 18-month intervention period.

RESULTS

In the intervention arm, mean adherence was 35.2% (SD = 5.8%) and 43.6% (SD = 27.5%) for asphyxia; 25.0% (SD = 14.8%) and 39.3% (SD = 27.7%) for jaundice; 52.0% (SD = 11.0%) and 75.0% (SD = 21.2%) for cord sepsis protocols in the pre-intervention and intervention periods respectively. In the control arm, mean adherence was 52.9% (SD = 16.4%) and 74.5% (SD = 14.7%) for asphyxia; 45.1% (SD = 12.8%) and 64.6% (SD = 8.2%) for jaundice; 53.8% (SD = 16.0%) and 60.8% (SD = 11.7%) for cord sepsis protocols in the pre-intervention and intervention periods respectively. We observed nonsignificant improvement in protocol adherence in the intervention clusters but significant improvement in protocol adherence in the control clusters. There were 2 concurrent neonatal health improvement activities in the intervention clusters and over 12 in the control clusters during the intervention period.

CONCLUSION

Whether mHealth interventions can improve adherence to neonatal health protocols in low-resource settings cannot be ascertained by this study. Neonatal health improvement activities are however likely to improve protocol adherence. Future mHealth evaluations of protocol adherence must account for other concurrent interventions in study contexts.

Seizure Susceptibility Correlates with Brain Injury in Male Mice Treated with Hypothermia after Neonatal Hypoxia-Ischemia

Hypoxic-ischemic encephalopathy is a common neonatal brain injury associated with significant morbidity and mortality despite the administration of therapeutic hypothermia (TH). Neonatal seizures and subsequent chronic epilepsy are frequent in this patient population and current treatments are partially effective. We used a neonatal murine hypoxia-ischemia (HI) model to test whether the severity of hippocampal and cortical injury predicts seizure susceptibility 8 days after HI and whether TH mitigates this susceptibility. HI at postnatal day 10 (P10) caused hippocampal injury not mitigated by TH in male or female pups. TH did not confer protection against flurothyl seizure susceptibility at P18 in this model. Hippocampal (R2 = 0.33, p = 0.001) and cortical (R2 = 0.33, p = 0.003) injury directly correlated with seizure susceptibility in male but not female pups. Thus, there are sex-specific consequences of neonatal HI on flurothyl seizure susceptibility in a murine neonatal HI model. Further studies are necessary to elucidate the underlying mechanisms of sex dimorphism in seizure susceptibility after neonatal HI.

Catatonia Associated With a SCN2A-Related Disorder in a 4-Year-Old Child

Catatonia is a rare, underdiagnosed syndrome in children. We report the case of a 4-year-old child admitted for recent social withdrawal alternating with psychomotor excitement, verbigeration, and a loss of toilet readiness. He had a history of neonatal seizures, had been stabilized with vigabatrin, and was seizure free without treatment for several months. The pediatric and psychiatric examination revealed motor stereotypes, mannerism, bilateral mydriasis, and visual hallucinations. Laboratory and brain imaging explorations were initially negative. Catatonic symptoms, as measured with the Pediatric Catatonia Rating Scale, significantly decreased after introducing lorazepam, the first-line recommended treatment of this condition. On the basis of the neonatal seizure history, complementary genetic investigations were performed and revealed a mutation in the SCN2A gene, which encodes the voltage-gated sodium channel Nav1.2. Catatonic symptoms progressively disappeared after reintroducing vigabatrin. At the syndromic level, catatonia in young children appears responsive to high-dose lorazepam and is well monitored by using the Pediatric Catatonia Rating Scale. This case reveals the need for wide-ranging explorations in early-onset catatonia because specific targeted treatments might be available.

Population pharmacokinetics of levetiracetam in neonates with seizures

WHAT IS KNOWN AND OBJECTIVE

This study developed a population pharmacokinetic (PK) model of levetiracetam (LEV) for treating neonatal seizures (NS) and determined the influence of clinically relevant covariates to explain the interindividual variability and residual error.

METHODS

Twenty newborns admitted to the Neonatal Intensive Care Unit at the Hospital Central "Dr. Ignacio Morones Prieto" were included. LEV doses were administered by intermittent infusion. Blood samples were drawn 3 times post-infusion. Levetiracetam was quantified by a chromatographic technique. NONMEM software was used to determine the population PK model of LEV in neonates and the influence of clinical covariates on drug disposition.

RESULTS AND DISCUSSION

The LEV PK in neonates is described by a one-compartment open model with first-order elimination. The influence of creatinine clearance (CRCL) and body weight (BW) on clearance (CL[L/h] = 0.47*CRCL), as well as the volume of the distribution (Vd[L] = 0.65*BW) of LEV, were confirmed, considering interindividual variabilities of 36% and 22%, respectively, and a residual error of 13%.

WHAT IS NEW AND CONCLUSION

Based on the PK of LEV in neonates and the influence of the final PK model, a priori dosing guidelines are proposed considering CRCL, BW and LEV plasma concentrations between 6 and 20 mg/L for NS treatment.

Variability in Preferred Management of Electrographic Seizures in Neonatal Hypoxic Ischemic Encephalopathy

BACKGROUND

Seizures may cause added harm in neonates with hypoxic-ischemic encephalopathy (HIE). Specific recommendations about seizure treatment in this context are lacking. We sought to determine the scope of practice regarding management of non-status epilepticus electrographic-only seizures in this setting.

METHODS

A case-based survey was distributed to members of the Child Neurology Society. Providers were asked about their preferred management strategy for sequential clinical scenarios.

RESULTS

A total of 177 child neurologists responded to the survey. Seventy-seven percent of providers would treat 20 seconds or less of electrographic seizure activity. In a neonate with mild HIE and an electrographic-only seizure, there was no agreement among providers regarding whether to start maintenance therapy in addition to a one-time anti-seizure drug load. In a neonate with moderate HIE on phenobarbital for early electro-clinical seizures, most providers would escalate treatment for ongoing electrographic-only seizures by increasing phenobarbital dosing. In a neonate with severe HIE complicated by status epilepticus on phenobarbital who subsequently develops recurrent electrographic-only seizures, providers varied substantially in their management preferences. For all three cases, 75% to 85% of providers would not change their management preferences based on the absence of a clinical correlate with the electrographic seizure.

CONCLUSIONS

We found marked variability among providers regarding preferred management of non-status epilepticus electrographic-only seizures after HIE. Our results identified specific aspects of electrographic-only seizure management in neonatal HIE where there is limited consensus. These discrepancies may serve as opportunities for future investigation.

[Revelation of the circumstances of the accident vascular arterial ischemic brain in at term or near-term and referral]

The neonatal arterial ischemic stroke is an emergency. Recurrent focal seizures, generally occurring in the first 24-72 hours after birth, are the commonest first clinical signs. When neonatal arterial ischemic stroke is suspected, optimal initial management involves careful supportive care including treatment of clinical and frequent or prolonged subclinical seizures, correction of the possible metabolic disorders and their prevention. Contrary to hypoxic ischemic encephalopathy, therapeutic hypothermia is not indicated. This newborn requires emergent transfer to a neonatal intensive care unit for the confirmation of the diagnosis by means of a specialized neonatal transport team.

A Distinctive Ictal Amplitude-Integrated Electroencephalography Pattern in Newborns with Neonatal Epilepsy Associated with KCNQ2 Mutations

BACKGROUND

Recurrent and prolonged seizures are harmful for the developing brain, emphasizing the importance of early seizure recognition and effective therapy. Amplitude-integrated electroencephalography (aEEG) has become a valuable tool to diagnose epileptic seizures, and, in parallel, genetic etiologies are increasingly being recognized, changing the paradigm of the workup and management of neonatal seizures.

OBJECTIVE

To report the ictal aEEG pattern in neonates with KCNQ2-related epilepsy.

SUBJECTS AND METHODS

In this multicenter descriptive study, clinical data and aEEG findings of 9 newborns with KCNQ2 mutations are reported.

RESULTS

Refractory seizures occurred in the early neonatal period with similar seizure type, including tonic features, apnea, and desaturation. A distinct aEEG seizure pattern, consisting of a sudden rise of the lower and upper margin of the aEEG, followed by a marked depression of the aEEG amplitude, was found in 8 of the 9 patients. Prompt recognition of this pattern led to early treatment with carbamazepine in the 2 most recent cases.

CONCLUSION

Early recognition of the electroclinical phenotype by using aEEG may direct genetic testing and a precision medicine approach with sodium channel blockers in neonates with KCNQ2 mutations.

Seizures in the paediatric emergency department

Seizures are a common presentation to emergency departments. Early intervention improves treatment response. Use of consensus guidelines is highly recommended to decrease drug side effects and reduce intensive care requirements. Benzodiazepines remain the mainstay of first-line treatment. Choice of drugs for second-line treatment is expanding and some important studies are currently underway to determine which of these agents has the best safety and effectiveness profile in children.

Improving the outcome of bacterial meningitis in newborn infants in Africa: reflections on recent progress

PURPOSE OF REVIEW

There has been a reduction in overall under fives mortality (UFM) but neonatal mortality has not fallen at the same rate as for older children. Bacterial meningitis remains a common, often unrecognized and devastating illness in many African newborns with high mortality and morbidity. Further progress in reducing UFM has to focus on quality of care for neonates. Recent efforts to improve diagnosis, treatment and outcome are reviewed.

RECENT FINDINGS

Diagnosis is often unsupported by laboratory tests and efforts have been made to improve the clinical diagnosis of bacterial meningitis. Simpler, robust bedside tests are being devised. The cause of bacterial meningitis is changing and first-line antimicrobial therapy and adjuvant therapies are evaluated. Programmes to reduce risk factors and prevent neonatal infections are identified.

SUMMARY

Neonatal care needs to improve in first referral hospitals with simple, low-cost, validated measures provided as bundles of care for both mother and child. First-line antibiotic therapy must be reconsidered in the light of increased infections by multiresistant and Gram-negative bacteria. Studies are needed for effective and safe lengths of antimicrobial therapy, the role of adjuvant therapy and the best anticonvulsants to use.

Multiscale Entropy of Electroencephalogram as a Potential Predictor for the Prognosis of Neonatal Seizures

Objective

Increasing animal studies supported the harmful effects of prolonged or frequent neonatal seizures in developing brain, including increased risk of later epilepsy. Various nonlinear analytic measures had been applied to investigate the change of brain complexity with age. This study focuses on clarifying the relationship between later epilepsy and the changes of electroencephalogram (EEG) complexity in neonatal seizures.

Methods

EEG signals from 19 channels of the whole brain from 32 neonates below 2 months old were acquired. The neonates were classified into 3 groups: 9 were normal controls, 9 were neonatal seizures without later epilepsy, and 14 were neonatal seizures with later epilepsy. Sample entropy (SamEn), multiscale entropy (MSE) and complexity index (CI) were analyzed.

Results

Although there was no significant change in SamEn, the CI values showed significantly decreased over Channels C3, C4, and Cz in patients with neonatal seizures and later epilepsy compared with control group. More multifocal epileptiform discharges in EEG, more abnormal neuroimaging findings, and higher incidence of future developmental delay were noted in the group with later epilepsy.

Conclusions

Decreased MSE and CI values in patients with neonatal seizures and later epilepsy may reflect the mixed effects of acute insults, underlying brain immaturity, and prolonged seizures-related injuries. The analysis of MSE and CI can therefore provide a quantifiable and accurate way to decrypt the mystery of neonatal seizures, and could be a promising predictor.

Neonatal seizures-part 2: Aetiology of acute symptomatic seizures, treatments and the neonatal epilepsy syndromes

Most neonatal epileptic seizures are provoked by an underlying condition or problem-'acute symptomatic seizures'. However, a few neonatal epilepsy syndromes exist, and these are defined by the constellation of seizure types, EEG findings and family history seen. Making an accurate diagnosis of an epilepsy syndrome can help direct investigations, treatment options and provide prognostic information. This article discusses the investigative approach and treatments for neonatal epileptic seizures, including the neonatal epilepsy syndromes.

Levetiracetam in neonatal seizures: a review

Phenobarbital and phenytoin have been the mainstay treatment modalities for neonatal seizures. Studies have revealed these agents control seizures in less than half of neonates, can cause neuronal apoptosis in vitro, and have highly variable pharmacokinetics in neonates. In contrast, there have been no reports of levetiracetam causing these neurotoxic effects. Due to its favorable side effect and pharmacokinetic profiles and positive efficacy outcomes in neonatal studies to date, there is great interest in the use of levetiracetam for neonatal seizures. This article reviews the literature regarding the safety of levetiracetam in neonates and its efficacy in neonatal seizures.

Anticonvulsant effectiveness and hemodynamic safety of midazolam in full-term infants treated with hypothermia

BACKGROUND

Midazolam is used as an anticonvulsant in neonatology, including newborns with perinatal asphyxia treated with hypothermia. Hypothermia may affect the safety and effectiveness of midazolam in these patients.

OBJECTIVES

The objective was to evaluate the anticonvulsant effectiveness and hemodynamic safety of midazolam in hypothermic newborns and to provide dosing guidance.

METHODS

Hypothermic newborns with perinatal asphyxia and treated with midazolam were included. Effectiveness was studied using continuous amplitude-integrated electroencephalography. Hemodynamic safety was assessed using pharmacokinetic-pharmacodynamic modeling with plasma samples and blood pressure recordings (mean arterial blood pressure) under hypothermia.

RESULTS

No effect of therapeutic hypothermia on pharmacokinetics could be identified. Add-on seizure control with midazolam was limited (23% seizure control). An inverse relationship between the midazolam plasma concentration and mean arterial blood pressure could be identified. At least one hypotensive episode was experienced in 64%. The concomitant use of inotropes decreased midazolam clearance by 33%.

CONCLUSIONS

Under therapeutic hypothermia, midazolam has limited add-on clinical anticonvulsant effectiveness after phenobarbital administration. Due to occurrence of hypotension requiring inotropic support, midazolam is less suitable as a second-line anticonvulsant drug under hypothermia.

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.

Levetiracetam increases neonatal hypoxic-ischemic brain injury under normothermic, but not hypothermic conditions

BACKGROUND

Hypoxic-ischemic encephalopathy (HIE) resulting from perinatal asphyxia often leads to severe neurologic impairment or even death. There is a need to advance therapy for infants with HIE, for example to combine hypothermia with pharmacological treatment strategies. Levetiracetam (LEV) is approved for clinical administration to infants older than 4 weeks of age and is also used off-label in neonates. Furthermore, LEV was shown to be neuroprotective in adult animal models of brain injury.

AIM OF THE STUDY

The aim of this study was to evaluate the neuroprotective potential of LEV in vitro using primary hippocampal neurons, and in vivo using an established model of neonatal hypoxic-ischemic brain injury.

RESULTS

LEV treatment per se did not induce neurotoxicity in the developing rodent brain. Following oxygen glucose deprivation, we observed some, although not a significant, increase in cell death after LEV treatment. In vivo, LEV was administered under normothermic and hypothermic conditions following hypoxic-ischemic brain damage. LEV administration significantly increased brain injury under normothermic conditions. Compared to the normothermia-treated group, in the hypothermia group LEV administration did not increase hypoxic-ischemic brain injury.

DISCUSSION

This study demonstrates that LEV treatment increases neonatal hypoxic-ischemic brain injury. Administration of LEV in the acute phase of the injury might interfere with the balanced activation and inactivation of excitatory and inhibitory receptors in the developing brain. The neurotoxic effect of LEV in the injured newborn brain might further suggest an agonistic effect of LEV on the GABAergic system. Hypothermia treatment attenuates glutamate release following hypoxic-ischemic brain injury and might therefore limit the potentially deleterious effects of LEV. As a consequence, our findings do not necessarily rule out a potentially beneficial effect, but argue for cautious use of LEV in newborn infants with pre-existing brain injury.

Newly emerging therapies for neonatal seizures

The treatment of neonatal seizures has not changed significantly over the last 50 years despite advances in antiepileptic drug (AED) development for older children and adults. Recently new drugs have emerged some of which address age-specific challenges or mechanisms and will be discussed in this review. The loop diuretic bumetanide blocks the neuronal NKCC1 co-transporter and is thought specifically to supress seizures in the immature brain. Levetiracetam has been used in children and infants with good efficacy, an excellent safety profile, and near-ideal pharmacokinetic characteristics. Randomised controlled trials are now underway to test the efficacy of some newer AEDs for neonatal seizures. Topiramate has been shown to have neuroprotective properties in addition to its antiepileptic action and trials in babies with hypoxic-ischaemic encephalopathy are now planned. There is an urgent need to develop age-specific AEDs for preterm and term babies. These drugs must be evaluated with multicentre, collaborative trials using innovative methods and high ethical standards to overcome age-specific challenges with the ultimate aim of improving the outcome for neonates with seizures.