Incidence of seizures on continuous EEG monitoring following traumatic brain injury in children

Effectiveness of Fosphenytoin and Levetiracetam to Prevent Posttraumatic Seizures in Young Children with Accidental or Abusive Traumatic Brain Injury

BACKGROUND

Seizures occur frequently in pediatric patients with traumatic brain injury (TBI), particularly abusive head trauma (AHT). There are limited data on the effectiveness of fosphenytoin and levetiracetam to prevent posttraumatic seizures.

METHODS

We performed a retrospective single center cohort study of children < 3 years old admitted with mild [Glasgow Coma Scale (GCS) score 13-15], moderate (GCS 9-12), and severe (GCS 3-8) TBI at a level I trauma center from 2011 to 2021. Antiseizure medications were used at the discretion of the treating physicians. Nonparametric tests were used to compare antiseizure medication prophylaxis and TBI etiology.

RESULTS

A total of 717 patients (263 with AHT, 454 with accidental TBI) were included, of whom 135 (19%) received fosphenytoin, 152 (21%) received levetiracetam, and 430 (60%) did not receive any seizure prophylaxis. Over the study period, the use of fosphenytoin prophylaxis decreased (R2 = 0.67, p = 0.004), whereas the use of levetiracetam increased (R2 = 0.51, p = 0.008). Additionally, the occurrence of early posttraumatic seizures decreased (R2 = 0.58, p = 0.006). Children with AHT were more likely to receive any seizure prophylaxis than those with accidental TBI (52% vs. 27%; p < 0.001) and were more likely to have ≥ 1 seizure during hospitalization (22% vs. 4%; p < 0.001). Among children who received seizure prophylaxis, those who received fosphenytoin had a higher occurrence of seizures than those who received levetiracetam (33% vs.18%; p = 0.004). After controlling for age, admission year, TBI mechanism, and severity of injury, we observed no differences in seizure occurrence between groups.

CONCLUSIONS

In children < 3 years old with TBI, no differences were observed in occurrence of seizures between patients who received fosphenytoin and patients who received levetiracetam prophylaxis after controlling for patient factors including severity of injury. Levetiracetam may be an equally effective alternative to fosphenytoin for seizure prophylaxis for early posttraumatic seizure prevention in this age group.

Electroencephalogram pattern predicting neurological outcomes of children with seizures secondary to abusive head trauma

BACKGROUND

The clinical presentations of abusive head trauma can abruptly worsen, so the occurrence of seizures and changes of EEG can be variable according to patients' conditions. Since the changes of EEG background waves reflect the cortical function of children, we aimed to find out whether the timing of EEG background, epileptiform discharges and seizure patterns were associated with the outcomes of patients with AHT.

MATERIAL AND METHODS

Using seizure type and acute stage electroencephalographic (EEG) characteristics to assess adverse neurological outcomes in children with seizures secondary to abusive head trauma (AHT). Children who were hospitalized with AHT at a tertiary referral hospital from October 2000 to April 2010 were evaluated retrospectively. A total of 50 children below 6 years of age admitted due to AHT were included. KOSCHI outcome scale was used to evaluate the primary outcome and neurological impairment was used as secondary outcome after 6 months discharge.

RESULTS

Children with apnea, cardiac arrest, reverse blood flow and skull fracture in clinic had a higher mortality rate even in the no-seizure group (3/5 [60%] vs. 3/45 [6.7%], odds ratio [OR] = 11; 95% CI = 2.3-52; p = 0.025). Seizure occurrence reduced mostly at the second day after admission in seizure groups; but children with persistent seizures for 1 week showed poor neurological outcomes. The occurrence of initial seizure was frequency associated with younger age; focal seizure, diffuse cortical dysfunction in acute-stage EEG, and low Glasgow Coma Scale (GCS) score were significantly related to poor outcomes after 6 months. Diffuse cortical dysfunction was also associated with motor, speech, and cognitive dysfunction.

CONCLUSIONS

Diffuse cortical dysfunction in acute-stage EEG combined with low GCS score and focal seizure may related to poor outcomes and neurological dysfunctions in children with AHT.

EEG Monitoring in Critically Ill Children: Establishing High-Yield Subgroups

PURPOSE

Continuous EEG monitoring (CEEG) is increasingly used to identify electrographic seizures (ES) in critically ill children, but it is resource intense. We aimed to assess how patient stratification by known ES risk factors would impact CEEG utilization.

METHODS

This was a prospective observational study of critically ill children with encephalopathy who underwent CEEG. We calculated the average CEEG duration required to identify a patient with ES for the full cohort and subgroups stratified by known ES risk factors.

RESULTS

ES occurred in 345 of 1,399 patients (25%). For the full cohort, an average of 90 hours of CEEG would be required to identify 90% of patients with ES. If subgroups of patients were stratified by age, clinically evident seizures before CEEG initiation, and early EEG risk factors, then 20 to 1,046 hours of CEEG would be required to identify a patient with ES. Patients with clinically evident seizures before CEEG initiation and EEG risk factors present in the initial hour of CEEG required only 20 (<1 year) or 22 (≥1 year) hours of CEEG to identify a patient with ES. Conversely, patients with no clinically evident seizures before CEEG initiation and no EEG risk factors in the initial hour of CEEG required 405 (<1 year) or 1,046 (≥1 year) hours of CEEG to identify a patient with ES. Patients with clinically evident seizures before CEEG initiation or EEG risk factors in the initial hour of CEEG required 29 to 120 hours of CEEG to identify a patient with ES.

CONCLUSIONS

Stratifying patients by clinical and EEG risk factors could identify high- and low-yield subgroups for CEEG by considering ES incidence, the duration of CEEG required to identify ES, and subgroup size. This approach may be critical for optimizing CEEG resource allocation.

Late-Onset Findings During Extended EEG Monitoring Are Rare in Critically Ill Children

PURPOSE

Electrographic seizures (ES) are common in critically ill children undergoing continuous EEG (CEEG) monitoring, and previous studies have aimed to target limited CEEG resources to children at highest risk of ES. However, previous studies have relied on observational data in which the duration of CEEG was clinically determined. Thus, the incidence of late occurring ES is unknown. The authors aimed to assess the incidence of ES for 24 hours after discontinuation of clinically indicated CEEG.

METHODS

This was a single-center prospective study of nonconsecutive children with acute encephalopathy in the pediatric intensive care unit who underwent 24 hours of extended research EEG after the end of clinical CEEG. The authors assessed whether there were new findings that affected clinical management during the extended research EEG, including new-onset ES.

RESULTS

Sixty-three subjects underwent extended research EEG. The median duration of the extended research EEG was 24.3 hours (interquartile range 24.0-25.3). Three subjects (5%) had an EEG change during the extended research EEG that resulted in a change in clinical management, including an increase in ES frequency, differential diagnosis of an event, and new interictal epileptiform discharges. No subjects had new-onset ES during the extended research EEG.

CONCLUSIONS

No subjects experienced new-onset ES during the 24-hour extended research EEG period. This finding supports observational data that patients with late-onset ES are rare and suggests that ES prediction models derived from observational data are likely not substantially underrepresenting the incidence of late-onset ES after discontinuation of clinically indicated CEEG.

Neuromonitoring in Children with Traumatic Brain Injury

Traumatic brain injury remains a major cause of mortality and morbidity in children across the world. Current management based on international guidelines focuses on a fixed therapeutic target of less than 20 mm Hg for managing intracranial pressure and 40-50 mm Hg for cerebral perfusion pressure across the pediatric age group. To improve outcome from this complex disease, it is essential to understand the pathophysiological mechanisms responsible for disease evolution by using different monitoring tools. In this narrative review, we discuss the neuromonitoring tools available for use to help guide management of severe traumatic brain injury in children and some of the techniques that can in future help with individualizing treatment targets based on advanced cerebral physiology monitoring.

Electrographic Seizure Characteristics and Electrographic Status Epilepticus Prediction

PURPOSE

We aimed to characterize electrographic seizures (ES) and electrographic status epilepticus (ESE) and determine whether a model predicting ESE exclusively could effectively guide continuous EEG monitoring (CEEG) utilization in critically ill children.

METHODS

This was a prospective observational study of consecutive critically ill children with encephalopathy who underwent CEEG. We used descriptive statistics to characterize ES and ESE, and we developed a model for ESE prediction.

RESULTS

ES occurred in 25% of 1,399 subjects. Among subjects with ES, 23% had ESE, including 37% with continuous seizures lasting >30 minutes and 63% with recurrent seizures totaling 30 minutes within a 1-hour epoch. The median onset of ES and ESE occurred 1.8 and 0.18 hours after CEEG initiation, respectively. The optimal model for ESE prediction yielded an area under the receiver operating characteristic curves of 0.81. A cutoff selected to emphasize sensitivity (91%) yielded specificity of 56%. Given the 6% ESE incidence, positive predictive value was 11% and negative predictive value was 99%. If the model were applied to our cohort, then 53% of patients would not undergo CEEG and 8% of patients experiencing ESE would not be identified.

CONCLUSIONS

ESE was common, but most patients with ESE had recurrent brief seizures rather than long individual seizures. A model predicting ESE might only slightly improve CEEG utilization over models aiming to identify patients at risk for ES but would fail to identify some patients with ESE. Models identifying ES might be more advantageous for preventing ES from evolving into ESE.

Review of Noninvasive Neuromonitoring Modalities in Children II: EEG, qEEG

Critically ill children with acute neurologic dysfunction are at risk for a variety of complications that can be detected by noninvasive bedside neuromonitoring. Continuous electroencephalography (cEEG) is the most widely available and utilized form of neuromonitoring in the pediatric intensive care unit. In this article, we review the role of cEEG and the emerging role of quantitative EEG (qEEG) in this patient population. cEEG has long been established as the gold standard for detecting seizures in critically ill children and assessing treatment response, and its role in background assessment and neuroprognostication after brain injury is also discussed. We explore the emerging utility of both cEEG and qEEG as biomarkers of degree of cerebral dysfunction after specific injuries and their ability to detect both neurologic deterioration and improvement.

Electroencephalography Findings in Traumatic Brain Injury

Traumatic Brain Injury (TBI) or also known as a head injury is one of the leading causes of death among young people and is also one of the health problems defined as impact, penetration, and rapid movement of the brain within the skull that can result in changes in mental status and is often referred to as the silent epidemic.

Head injuries can also result in electrophysiological abnormalities seen on electroencephalography (EEG) recordings. Electroencephalography was the first clinical neurodiagnostic assessment to reveal abnormal brain function after a head injury. For detecting brain injury, EEG may be more sensitive than clinical neurologic examination.

In general conditions, electroencephalography is performed on patients with moderate to severe head injuries to provide information about the severity of the head injury, and establish a diagnosis of non-convulsive status epilepticus. This diagnosis often follows head injuries because patients with loss of consciousness are difficult to identify without an EEG examination. This also helps determine a prognosis for recovery and the likelihood of post-traumatic seizures.

Electroencephalography features in head injuries depend on the severity of the injury and the location of the head itself. Electroencephalography after head injury shows slowing of the posterior dominant rhythm and increasing diffuse theta slowing, which returns to normal within hours or may subside more slowly over several weeks. Electroencephalography changes are not the same in each individual, due to differences in the severity of head injuries. It is important to know that there is no clear or specific EEG for mild traumatic brain injury.

Incidence of post-traumatic seizures in children during combat operations in Afghanistan and Iraq

OBJECTIVES

Children represent a significant portion of the patient population treated at combat support hospitals. There is significant data regarding post injury seizures in adults but with children it is lacking. We seek to describe the incidence of post-traumatic seizures within this population.

METHODS

This is a secondary analysis of previously described data from the Department of Defense Trauma Registry (DODTR). Within our dataset, we searched for documentation of seizures after admission.

RESULTS

Of the 3439 encounters in our dataset, we identified 37 casualties that had a documented seizure after admission. Most were in the 1-4 year age group (37.8%), male (59.4%), injured by explosive (40.5%), with serious injuries to the head/neck (75.6%). The median ISS was higher in the seizure group (22 versus 10, p<0.001). Most survived to hospital discharge with no statistically significant increased mortality noted in the seizure group (seizure 90.2% versus 91.8%, p = 1.000). In the prehospital setting, the seizure group was more frequently intubated (16.2% versus 6.0%, p = 0.023), received ketamine (20.0% versus 3.2%, p<0.001), and administered an anti-seizure medication (5.4% versus 0.1%, p = 0.001). In the hospital setting, the seizure group was more frequently intubated (56.7% versus 17.7%, p<0.001), had intracranial pressure monitoring (24.3% versus 2.6%, p<0.001), craniectomy (10.8% versus 2.5%, p = 0.014), and craniotomy (21.6% versus 4.7%, p<0.001).

CONCLUSIONS

Within our dataset, we found an incidence of 1% of pediatric casualties experiencing a post-traumatic seizure. While this number appears infrequent, there is likely significant under detection of subclinical seizures.

The Role of Electroencephalography in the Prognostication of Clinical Outcomes in Critically Ill Children: A Review

Electroencephalography (EEG) is a neurologic monitoring modality that allows for the identification of seizures and the understanding of cerebral function. Not only can EEG data provide real-time information about a patient’s clinical status, but providers are increasingly using these results to understand short and long-term prognosis in critical illnesses. Adult studies have explored these associations for many years, and now the focus has turned to applying these concepts to the pediatric literature. The aim of this review is to characterize how EEG can be utilized clinically in pediatric intensive care settings and to highlight the current data available to understand EEG features in association with functional outcomes in children after critical illness. In the evaluation of seizures and seizure burden in children, there is abundant data to suggest that the presence of status epilepticus during illness is associated with poorer outcomes and a higher risk of mortality. There is also emerging evidence indicating that poorly organized EEG backgrounds, lack of normal sleep features and lack of electrographic reactivity to clinical exams portend worse outcomes in this population. Prognostication in pediatric critical illness must be informed by the comprehensive evaluation of a patient’s clinical status but the utilization of EEG may help contribute to this assessment in a meaningful way.

Early prognostic factors for morbidity and mortality in severe traumatic brain injury. Experience in a child polytrauma unit

OBJECTIVE

To identify early prognostic factors that lead to an increased risk of unfavorable prognosis.

DESIGN

Observational cohort study from October 2002 to October 2017.

SETTING AND PATIENTS

Patients with severe TBI admitted to intensive care were included.

VARIABLES AND INTERVENTIONS

Epidemiological, clinical, analytical and therapeutic variables were collected. The functional capacity of the patient was assessed at 6 months using the Glasgow Outcome Scale (GOS). An unfavorable prognosis was considered a GOS less than or equal to 3. A univariate analysis was performed to compare the groups with good and bad prognosis and their relationship with the different variables. A multivariate analysis was performed to predict the patient's prognosis.

RESULTS

98 patients were included, 61.2% males, median age 6.4 years (IQR 2.49-11.23). 84.7% were treated by the out-of-hospital emergency services. At 6 months, 51% presented satisfactory recovery, 26.5% moderate sequelae, 6.1% severe sequelae, and 2% vegetative state. 14.3% died. Statistical significance was found between the score on the prehospital Glasgow coma scale, pupillary reactivity, arterial hypotension, hypoxia, certain analytical and radiological alterations, such as compression of the basal cisterns, with an unfavorable prognosis. The multivariate analysis showed that it is possible to make predictive models of the evolution of the patients.

CONCLUSIONS

it is possible to identify prognostic factors of poor evolution in the first 24 h after trauma. Knowledge of them can help clinical decision-making as well as offer better information to families.

Pediatric Neurocritical Care

Brain injury in children is a major public health problem, causing substantial morbidity and mortality. Cause of pediatric brain injury varies widely and can be from a primary neurologic cause or as a sequela of multisystem illness. This review discusses the emerging field of pediatric neurocritical care (PNCC), including current techniques of imaging, treatment, and monitoring. Future directions of PNCC include further expansion of evidence-based practice guidelines and establishment of multidisciplinary PNCC services within institutions.

Multimodal Neurologic Monitoring in Children With Acute Brain Injury

Children with acute neurologic illness are at high risk of mortality and long-term neurologic disability. Severe traumatic brain injury, cardiac arrest, stroke, and central nervous system infection are often complicated by cerebral hypoxia, hypoperfusion, and edema, leading to secondary neurologic injury and worse outcome. Owing to the paucity of targeted neuroprotective therapies for these conditions, management emphasizes close physiologic monitoring and supportive care. In this review, we will discuss advanced neurologic monitoring strategies in pediatric acute neurologic illness, emphasizing the physiologic concepts underlying each tool. We will also highlight recent innovations including novel monitoring modalities, and the application of neurologic monitoring in critically ill patients at risk of developing neurologic sequelae.

Associations between Electroencephalographic Variables, Early Post-Traumatic Seizure Risk, and Outcomes following Pediatric Severe Traumatic Brain Injury

Early post-traumatic seizures (PTS) are associated with worse outcomes in children with traumatic brain injury (TBI). Our aim was to identify the association between continuous electroencephalogram (cEEG) characteristics and early PTS risk following pediatric severe TBI. We also evaluated the relationship between cEEG background features and outcomes. A single-center retrospective cohort study was performed on children between 0 and 18 years of age admitted to the pediatric intensive care unit from 2016 to 2019 with severe TBI and cEEG monitoring within 7 days of injury. Raw cEEG tracings were reviewed by an epileptologist in accordance with American Clinical Neurophysiology Society (ACNS) Critical Care EEG terminology. Univariate comparisons were made between children with and without early PTS, as well as between those with and without varying cEEG background features. Eighteen children (31%) of the 59 included had early PTS. Interictal abnormalities, inclusive of sporadic spikes and sharp waves, rhythmic delta activity, or lateralized periodic discharges (LPDs) were more common among children with seizures (100 vs. 22%; p < 0.01). LPDs were also more common in the seizure group (44 vs. 2%; p < 0.01). Background discontinuity was associated with worse Glasgow Outcome Scale—Extended Pediatric Version (GOS-E Peds) scores at discharge and 3-, 6-, and 12-month post-discharge (p < 0.01). Lack of reactivity was also associated with worse GOS-E Peds scores at 3-, 6-, and 12-month post-discharge (p < 0.01). Interictal abnormalities and LPDs were each associated with early PTS following pediatric severe TBI. Larger studies should evaluate if high-risk patients would benefit from prolonged cEEG monitoring and/or more aggressive anti-seizure prophylaxis. Discontinuity and lack of variability were associated with worse outcomes. Future studies should attempt to clarify their role as potential early markers of prognosis.

Early posttraumatic seizures in pediatric traumatic brain injury: a multicenter analysis

OBJECTIVE

Early posttraumatic seizures (EPTSs) in children after traumatic brain injury (TBI) increase metabolic stress on the injured brain. The authors sought to study the demographic and radiographic predictors for EPTS, and to investigate the association between EPTS and death, and between EPTS and poor functional outcomes among children with moderate to severe TBI in Asia.

METHODS

A secondary analysis of a retrospective TBI cohort among participating centers of the Pediatric Acute & Critical Care Medicine Asian Network was performed. Children < 16 years of age with a Glasgow Coma Scale (GCS) score ≤ 13 who were admitted to pediatric intensive care units between January 2014 and October 2017 were included. Logistic regression analysis was performed to study risk factors for EPTS and to investigate the association between EPTS and death, and between EPTS and poor functional outcomes. Poor functional outcomes were defined as moderate disability, severe disability, and coma as defined by the Pediatric Cerebral Performance Category scale.

RESULTS

Overall, 313 children were analyzed, with a median age of 4.3 years (IQR 1.8-8.9 years); 162 children (51.8%) had severe TBI (GCS score < 8), and 76 children (24.3%) had EPTS. After adjusting for age, sex, and the presence of nonaccidental trauma (NAT), only younger age was significantly associated with EPTS (adjusted odds ratio [aOR] 0.85, 95% CI 0.78-0.92; p < 0.001). Forty-nine children (15.6%) in the cohort died, and 87 (32.9%) of the 264 surviving patients had poor functional outcomes. EPTS did not increase the risk of death. After adjusting for age, sex, TBI due to NAT, multiple traumas, and a GCS score < 8, the presence of EPTS was associated with poor functional outcomes (aOR 2.08, 95% CI 1.05-4.10; p = 0.036).

CONCLUSIONS

EPTSs were common among children with moderate to severe TBI in Asia and were associated with poor functional outcomes among children who survived TBI.

Perioperative routine EEG can reliably predict de novo seizures after supratentorial craniotomy

BACKGROUND

The contributing risk factors in development of seizure after supratentorial craniotomy, the optimal duration of prophylactic antiepileptic therapy, the high-risk patient to treat, and the drug of choice are subjects of debate as is the gold standard diagnostic tool for patient screening. Combining routine electroencephalography (EEG) with clinical data to identify high-risk patients and determine the ideal time of recording after surgery was the goal of this study.

METHODS

In this prospective cohort, 59 patients were evaluated with three EEG recordings after different intervals of supratentorial craniotomy due to different etiologies and were followed for 9 months for development of seizures. Demographic and disease-related variables as well as EEG results were analyzed to determine the contributing risk factors for development of seizures.

RESULTS

Neoplastic etiology and abnormal perioperative EEG (performed before surgery or in the first postoperative week) were the only independent variables associated with development of de novo seizure.

CONCLUSION

Routine EEG in the perioperative period and neoplastic etiology are two independent powerful predictors of developing seizure after supratentorial craniotomy and may help deciding whether to continue prophylactic antiepileptic medications for an extended period or not.

Continuous Electroencephalogram and Antiseizure Medication Use in an International Pediatric Traumatic Brain Injury Population

BACKGROUND

Electrographic seizures are frequent and associated with worse outcomes following traumatic brain injury (TBI). Despite this, the use of continuous electroencephalogram (cEEG) remains low. Our study describes cEEG usage and treatment dosing antiseizure medications (ASMs) in an international pediatric TBI population, hypothesizing that children monitored with cEEG have an increased rate of treatment ASMs because of electrographic seizure detection, compared with children who are not monitored with cEEG.

METHODS

This subanalysis of the TBI cohort of the international PANGEA study included children, 7 days to 17 years of age, with acute neurological insults admitted to pediatric intensive care units. We analyzed demographics, injury severity, and therapies including prophylactic or treatment ASMs. We evaluated the relationships between cEEG use, seizure frequency, and receipt of treatment ASMs. [Formula: see text] or Fisher's exact test was used to analyze categorical variables, and the Kruskal-Wallis or Mann-Whitney U-test was used for continuous variables. Multivariable analysis for treatment ASM use was performed using logistic regression.

RESULTS

One hundred-twenty-three of 174 patients with TBI were included. Twenty-seven patients (21.9%) underwent cEEG at any point during pediatric intensive care unit admission. Preexisting seizure disorder (18.2% vs. 2.3%, p = 0.014) and neuromuscular blockade use (52.4% vs. 24.1%, p = 0.011) were more frequently observed in the group monitored on cEEG when compared with those that were not. Presenting median Glasgow Coma Scale score was worse in the cEEG group (7 vs. 9, p = 0.044). There was no significant difference in age, use of intracranial pressure monitoring, or hyperosmolar therapy between the cEEG monitored and nonmonitored groups. Patients who were monitored on cEEG were more likely to receive a treatment dose ASM than those without cEEG monitoring (66.7% vs. 28.1%, p = 0.0002). When compared with those without treatment ASM, the treatment ASM group had more electrographic seizures on their first electroencephalogram following injury (51.6% vs. 4%, p = 0.0001) and more clinical seizures (55.8% vs. 0%, p < 0.0001).

CONCLUSIONS

Children monitored with cEEG after TBI have an increased prescription of treatment ASMs and clinical and electrographic seizures. The increased rate of treatment ASMs in the cEEG group may indicate increased recognition of electrographic seizures.

Early prognostic factors for morbidity and mortality in severe traumatic brain injury. Experience in a child polytrauma unit

OBJECTIVE

To identify early prognostic factors that lead to an increased risk of unfavorable prognosis.

DESIGN

Observational cohort study from October 2002 to October 2017.

SETTING AND PATIENTS

Patients with severe TBI admitted to intensive care were included.

VARIABLES AND INTERVENTIONS

Epidemiological, clinical, analytical and therapeutic variables were collected. The functional capacity of the patient was assessed at 6 months using the Glasgow Outcome Scale (GOS). An unfavorable prognosis was considered a GOS ≤3. A univariate analysis was performed to compare the groups with good and bad prognosis and their relationship with the different variables. A multivariate analysis was performed to predict the patient's prognosis.

RESULTS

A total of 98 patients were included, 61.2% males, median age 6.4years (IQR 2.49-11.23). 84.7% were treated by the out-of-hospital emergency services. At 6 months, 51% presented satisfactory recovery, 26.5% moderate sequelae, 6.1% severe sequelae, and 2% vegetative state. 14.3% died. Statistical significance was found between the score on the prehospital Glasgow coma scale, pupillary reactivity, arterial hypotension, hypoxia, certain analytical and radiological alterations, such as compression of the basal cisterns, with an unfavorable prognosis. The multivariate analysis showed that it is possible to make predictive models of the evolution of the patients.

CONCLUSIONS

It is possible to identify prognostic factors of poor evolution in the first 24hours after trauma. Knowledge of them can help clinical decision-making as well as offer better information to families.

Machine learning models to predict electroencephalographic seizures in critically ill children

OBJECTIVE

To determine whether machine learning techniques would enhance our ability to incorporate key variables into a parsimonious model with optimized prediction performance for electroencephalographic seizure (ES) prediction in critically ill children.

METHODS

We analyzed data from a prospective observational cohort study of 719 consecutive critically ill children with encephalopathy who underwent clinically-indicated continuous EEG monitoring (CEEG). We implemented and compared three state-of-the-art machine learning methods for ES prediction: (1) random forest; (2) Least Absolute Shrinkage and Selection Operator (LASSO); and (3) Deep Learning Important FeaTures (DeepLIFT). We developed a ranking algorithm based on the relative importance of each variable derived from the machine learning methods.

RESULTS

Based on our ranking algorithm, the top five variables for ES prediction were: (1) epileptiform discharges in the initial 30 minutes, (2) clinical seizures prior to CEEG initiation, (3) sex, (4) age dichotomized at 1 year, and (5) epileptic encephalopathy. Compared to the stepwise selection-based approach in logistic regression, the top variables selected by our ranking algorithm were more informative as models utilizing the top variables achieved better prediction performance evaluated by prediction accuracy, AUROC and F1 score. Adding additional variables did not improve and sometimes worsened model performance.

CONCLUSION

The ranking algorithm was helpful in deriving a parsimonious model for ES prediction with optimal performance. However, application of state-of-the-art machine learning models did not substantially improve model performance compared to prior logistic regression models. Thus, to further improve the ES prediction, we may need to collect more samples and variables that provide additional information.

Early Use of Antiseizure Medication in Mechanically Ventilated Traumatic Brain Injury Cases: A Retrospective Pediatric Health Information System Database Study

OBJECTIVES

Traumatic brain injury is a leading cause of morbidity and mortality in children. Post-traumatic seizures occur in 25% of children with severe traumatic brain injury and may worsen outcomes. Our objective was to use a retrospective cohort study to examine the association between the early seizure occurrence and the choice of early antiseizure medication in children with traumatic brain injury.

DESIGN

Retrospective cohort study using the Pediatric Health Information Systems database, 2010-2017.

SETTING

Fifty-one U.S. children's hospitals.

PATIENTS

Children (< 18 yr old at admission) with diagnostic codes for traumatic brain injury who were mechanically ventilated at the time of admission and with hospital length of stay greater than 24 hours.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 3,479 children were identified via coding and including in the analysis. Patients receiving antiseizure medication starting day 0 with levetiracetam were compared with those receiving phenytoin. The outcome was seizure occurrence, identified using validated International Classification of Diseases, 9th Revision, Clinical Modification and International Classification of Diseases, 10th Revision, Clinical Modification diagnosis codes. The median (interquartile range) age of patients was 4 (1-11) years, and the most common mechanism of injury was motor vehicle accident, occurring in 960 of patients (27%). A total of 2,342 patients (67%) received levetiracetam on day 0 and 1,137 patients (33%) received phenytoin on day 0. Totally 875 patients (37%) receiving levetiracetam on day 0 developed seizures, compared with 471 patients (41%) receiving phenytoin on day 0 (p = 0.02). Upon multivariable analysis adjusting for age, injury by child abuse, subdural hemorrhage, ethnicity, and admission year, children receiving phenytoin on day 0 were 1.26 (95% CI, 1.07-1.48) times more likely to be associated with post-traumatic seizure occurrence, compared with children receiving levetiracetam on day 0 (p = 0.01).

CONCLUSIONS

Early administration of levetiracetam was associated with less-frequent seizure occurrence than early administration of phenytoin in mechanically ventilated children with traumatic brain injury. Additional studies are necessary to determine if the association is causal or due to unmeasured confounders and/or selection bias.

EEG Monitoring After Convulsive Status Epilepticus

After convulsive status epilepticus, patients of all ages may have ongoing EEG seizures identified by continuous EEG monitoring. Furthermore, high EEG seizure exposure has been associated with unfavorable neurobehavioral outcomes. Thus, recent guidelines and consensus statements recommend many patients with persisting altered mental status after convulsive status epilepticus undergo continuous EEG monitoring. This review summarizes the available epidemiologic data and related recommendations provided by recent guidelines and consensus statements.

Acute Seizures-Work-Up and Management in Children

Seizures are common in the pediatric population; however, most children do not go on to develop epilepsy later in life. Selecting appropriate diagnostic modalities to determine an accurate diagnosis and appropriate treatment as well as with counseling families regarding the etiology and prognosis of seizures, is essential. This article will review updated definitions of seizures, including provoked versus unprovoked, as well as the International League Against Epilepsy operational definition of epilepsy. A variety of specific acute symptomatic seizures requiring special consideration are discussed, along with neonatal seizures and seizure mimics, which are common in pediatric populations.

Validation of a model to predict electroencephalographic seizures in critically ill children

OBJECTIVE

Electroencephalographic seizures (ESs) are common in encephalopathic critically ill children, but identification requires extensive resources for continuous electroencephalographic monitoring (CEEG). In a previous study, we developed a clinical prediction rule using three clinical variables (age, acute encephalopathy category, clinically evident seizure[s] prior to CEEG initiation) and two electroencephalographic (EEG) variables (EEG background category and interictal discharges within the first 30 minutes of EEG) to identify patients at high risk for ESs for whom CEEG might be essential. In the current study, we aimed to validate the ES prediction model using an independent cohort.

METHODS

The prospectively acquired validation cohort consisted of 314 consecutive critically ill children treated in the Pediatric Intensive Care Unit of a quaternary care referral hospital with acute encephalopathy undergoing clinically indicated CEEG. We calculated test characteristics using the previously developed prediction model in the validation cohort. As in the generation cohort study, we selected a 0.10 cutpoint to emphasize sensitivity.

RESULTS

The incidence of ESs in the validation cohort was 22%. The generation and validation cohorts were alike in most clinical and EEG characteristics. The ES prediction model was well calibrated and well discriminating in the validation cohort. The model had a sensitivity of 90%, specificity of 37%, positive predictive value of 28%, and negative predictive value of 93%. If applied, the model would limit 31% of patients from undergoing CEEG while failing to identify 10% of patients with ESs. The model had similar performance characteristics in the generation and validation cohorts.

SIGNIFICANCE

A model employing five readily available clinical and EEG variables performed well when validated in a new consecutive cohort. Implementation would substantially reduce CEEG utilization, although some patients with ESs would not be identified. This model may serve a critical role in targeting limited CEEG resources to critically ill children at highest risk for ESs.

EEG monitoring duration to identify electroencephalographic seizures in critically ill children

OBJECTIVES

To determine the optimal duration of continuous EEG monitoring (CEEG) for electrographic seizure (ES) identification in critically ill children.

METHODS

We performed a prospective observational cohort study of 719 consecutive critically ill children with encephalopathy. We evaluated baseline clinical risk factors (age and prior clinically evident seizures) and emergent CEEG risk factors (epileptiform discharges and ictal-interictal continuum patterns) using a multistate survival model. For each subgroup, we determined the CEEG duration for which the risk of ES was <5% and <2%.

RESULTS

ES occurred in 184 children (26%). Patients achieved <5% risk of ES after (1) 6 hours if ≥1 year without prior seizures or EEG risk factors; (2) 1 day if <1 year without prior seizures or EEG risks; (3) 1 day if ≥1 year with either prior seizures or EEG risks; (4) 2 days if ≥1 year with prior seizures and EEG risks; (5) 2 days if <1 year without prior seizures but with EEG risks; and (6) 2.5 days if <1 year with prior seizures regardless of the presence of EEG risks. Patients achieved <2% risk of ES at the same durations except patients without prior seizures or EEG risk factors would require longer CEEG (1.5 days if <1 year of age, 1 day if ≥1 year of age).

CONCLUSIONS

A model derived from 2 baseline clinical risk factors and emergent EEG risk factors would allow clinicians to implement personalized strategies that optimally target limited CEEG resources. This would enable more widespread use of CEEG-guided management as a potential neuroprotective strategy.

CLINICALTRIALSGOV IDENTIFIER

NCT03419260.

Development of a model to predict electroencephalographic seizures in critically ill children

OBJECTIVE

Electroencephalographic seizures (ESs) are common in encephalopathic critically ill children, but ES identification with continuous electroencephalography (EEG) monitoring (CEEG) is resource-intense. We aimed to develop an ES prediction model that would enable clinicians to stratify patients by ES risk and optimally target limited CEEG resources. We aimed to determine whether incorporating data from a screening EEG yielded better performance characteristics than models using clinical variables alone.

METHODS

We performed a prospective observational study of 719 consecutive critically ill children with acute encephalopathy undergoing CEEG in the pediatric intensive care unit of a quaternary care institution between April 2017 and February 2019. We identified clinical and EEG risk factors for ES. We evaluated model performance with area under the receiver-operating characteristic (ROC) curve (AUC), validated the optimal model with the highest AUC using a fivefold cross-validation, and calculated test characteristics emphasizing high sensitivity. We applied the optimal operating slope strategy to identify the optimal cutoff to define whether a patient should undergo CEEG.

RESULTS

The incidence of ES was 26%. Variables associated with increased ES risk included age, acute encephalopathy category, clinical seizures prior to CEEG initiation, EEG background, and epileptiform discharges. Combining clinical and EEG variables yielded better model performance (AUC 0.80) than clinical variables alone (AUC 0.69; P < .01). At a 0.10 cutoff selected to emphasize sensitivity, the optimal model had a sensitivity of 92%, specificity of 37%, positive predictive value of 34%, and negative predictive value of 93%. If applied, the model would limit 29% of patients from undergoing CEEG while failing to identify 8% of patients with ES.

SIGNIFICANCE

A model employing readily available clinical and EEG variables could target limited CEEG resources to critically ill children at highest risk for ES, making CEEG-guided management a more viable neuroprotective strategy.

Anomaly Detection in EEG Signals: A Case Study on Similarity Measure

Motivation. Anomaly EEG detection is a long-standing problem in analysis of EEG signals. The basic premise of this problem is consideration of the similarity between two nonstationary EEG recordings. A well-established scheme is based on sequence matching, typically including three steps: feature extraction, similarity measure, and decision-making. Current approaches mainly focus on EEG feature extraction and decision-making, and few of them involve the similarity measure/quantification. Generally, to design an appropriate similarity metric, that is compatible with the considered problem/data, is also an important issue in the design of such detection systems. It is however impossible to directly apply those existing metrics to anomaly EEG detection without any consideration of domain specificity. Methodology. The main objective of this work is to investigate the impacts of different similarity metrics on anomaly EEG detection. A few metrics that are potentially available for the EEG analysis have been collected from other areas by a careful review of related works. The so-called power spectrum is extracted as features of EEG signals, and a null hypothesis testing is employed to make the final decision. Two indicators have been used to evaluate the detection performance. One is to reflect the level of measured similarity between two compared EEG signals, and the other is to quantify the detection accuracy. Results. Experiments were conducted on two data sets, respectively. The results demonstrate the positive impacts of different similarity metrics on anomaly EEG detection. The Hellinger distance (HD) and Bhattacharyya distance (BD) metrics show excellent performances: an accuracy of 0.9167 for our data set and an accuracy of 0.9667 for the Bern-Barcelona EEG data set. Both of HD and BD metrics are constructed based on the Bhattacharyya coefficient, implying the priority of the Bhattacharyya coefficient when dealing with the highly noisy EEG signals. In future work, we will exploit an integrated metric that combines HD and BD for the similarity measure of EEG signals.

Electrographic seizure burden and outcomes following pediatric status epilepticus

Pediatric status epilepticus carries a substantial risk for morbidity and mortality, but the relationship between seizure burden, treatment, and outcome remains incompletely understood. This review summarizes the evidence linking seizure burden and outcomes among critically ill children in the intensive care unit (ICU), a population in whom accurate quantification of seizure burden is possible using continuous electroencephalographic monitoring. Several high-quality observational studies among critically ill children have reported an association between higher seizure burden and worse outcome, even after adjusting for potential confounders such as age, etiology, and illness severity. Although these studies support the hypothesis that seizures contribute to brain injury and worsen outcome, a causal link between seizures and outcome remains to be proven. The relationship between seizures and outcome is likely complex, and dependent on factors such as etiology, preexisting neurological disability, medication exposure, and possibly individual genetic factors. Studies attempting to define this complex relationship will need to measure and account for these factors in their analyses. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".

Clinical Characteristics and Nonconvulsive Seizures in Young Children With Abusive Head Trauma

AIM

We aimed to evaluate putative predictors of symptoms and signs at admission for nonconvulsive seizure and to examine the impact of nonconvulsive seizures on short-term outcomes.

METHOD

We retrospectively collected consecutive abusive head trauma patients (<36 months of age) from the trauma registry at Children's Healthcare of Atlanta between 2009 and 2014. Multiple logistic regression was performed to assess the putative predictors for the occurrence of nonconvulsive seizures including clinical seizures, altered mental status, respiratory difficulty, and cardiac arrest at admission, while controlling for age, sex, and injury severity. The Mann-Whitney U test and the Fisher exact test were used to compare the short-term outcomes between patients with and without nonconvulsive seizures.

RESULTS

Two hundred seventy patients with abusive head trauma were identified (male = 55.6%). The median age was 4 months (interquartile range = 2-8 months). Among 70 patients who underwent continuous electroencephalography (EEG), 40 had nonconvulsive seizures (57%) and 21 developed nonconvulsive status epilepticus (30%). Altered mental status at admission was associated with the occurrence of nonconvulsive seizures (odds ratio = 6.8, 95% confidence interval = 1.2-38.2, P = .03). Comparing patients with no seizures, those with nonconvulsive seizures were more likely to stay longer at hospital (9 days vs 14 days, P = .04) and to need rehabilitation (50.0% vs 63.2%, P = .03).

CONCLUSIONS

Nonconvulsive seizures and nonconvulsive status epilepticus was highly prevalent in young pediatric patients with abusive head trauma. Presenting with altered mental status at admission was found to predict the occurrence of nonconvulsive seizures. Nonconvulsive seizures had an unfavorable impact on short-term outcomes.

Clinical neurophysiology of altered states of consciousness: Encephalopathy and coma

The neurophysiologist will commonly encounter patients with encephalopathy/delirium (altered consciousness with impaired cognition, usually with sleep-wake cycle alteration and lethargy) or coma (an eyes-closed state of unresponsiveness) in the hospital setting. Assessing the background frequency of the EEG, as well as the presence or absence of other features (reactivity, periodic discharges such as triphasic waves), can provide insight into the patient's underlying condition and in some cases may provide prognostic information. The literature of postanoxic arrest EEG patterns continues to expand. Other neurophysiologic tests, such as somatosensory evoked potentials, auditory mismatch negativity, and even EMG, may also play a role in assessing brain function; distinguishing among a locked-in state, minimally conscious state, persistent vegetative state, and waking/unresponsive states; and assessing the potential for recovery after brain injury.

Nationwide incidence and risk factors for posttraumatic seizures in children with traumatic brain injury

OBJECTIVEPosttraumatic seizures (PTSs) are the most common complication following a traumatic brain injury (TBI) and may lead to posttraumatic epilepsy. PTS is well described in the adult literature but has not been studied extensively in children. Here, the authors utilized the largest nationwide registry of pediatric hospitalizations to report the national incidence, risk factors, and outcomes associated with PTS in pediatric TBI.METHODSThe authors queried the Kids' Inpatient Database (KID) using ICD-9-CM codes to identify all patients (age < 21 years) who had a primary diagnosis of TBI (850.xx-854.xx) and a secondary diagnosis of PTS (780.33, 780.39). Parameters of interest included patient demographics, preexisting comorbidities, hospital characteristics, nature of injury (open/closed), injury type (concussion, laceration/contusion, subarachnoid hemorrhage, subdural hematoma, or epidural hematoma), loss of consciousness (LOC), surgical management (Clinical Classification Software code 1 or 2), discharge disposition, in-hospital complications, and in-hospital mortality. The authors utilized the IBM SPSS statistical package (version 24) for univariate comparisons, as well as the identification of independent risk factors for PTS in multivariable analysis (alpha set at < 0.05).RESULTSThe rate of PTS was 6.9% among 124,444 unique patients hospitalized for TBI. The utilization rate of continuous electroencephalography (cEEG) was 0.3% and increased between 2003 (0.1%) and 2012 (0.7%). The most common etiologies of TBI were motor vehicle accident (n = 50,615), accidental fall (n = 30,847), and blunt trauma (n = 13,831). However, the groups with the highest rate of PTS were shaken infant syndrome (41.4%), accidental falls (8.1%), and cycling accidents (7.4%). In multivariable analysis, risk factors for PTS included age 0-5 years (compared with 6-10, 11-15, and 16-20 years), African American race (OR 1.4), ≥ 3 preexisting comorbidities (OR 4.0), shaken infant syndrome (OR 4.4), subdural hematoma (OR 1.6), closed-type injury (OR 2.3), brief LOC (OR 1.4), moderate LOC (OR 1.5), and prolonged LOC with baseline return (OR 1.8). Surgically managed patients were more likely to experience PTS (OR 1.5) unless they were treated within 24 hours of admission (OR 0.8). PTS was associated with an increased likelihood of in-hospital complications (OR 1.7) and adverse (nonroutine) discharge disposition (OR 1.2), but not in-hospital mortality (OR 0.5). The overall utilization rate of cEEG was 1.3% in PTS patients compared with 0.2% in patients without PTS. Continuous EEG monitoring was associated with higher rates of diagnosed PTS (35.4% vs 6.8%; OR 4.9, p < 0.001).CONCLUSIONSPTS is common in children with TBI and is associated with adverse outcomes. Independent risk factors for PTS include younger age (< 5 years), African American race, increased preexisting comorbidity, prolonged LOC, and injury pattern involving cortical exposure to blood products. However, patients who undergo urgent surgical evacuation are less likely to develop PTS.

Treatment options for posttraumatic epilepsy

PURPOSE OF REVIEW

Posttraumatic seizures (PTS) and posttraumatic epilepsy (PTE) are common and debilitating consequences of traumatic brain injury (TBI). Early PTS result in secondary brain injury by raising intracranial pressure and worsening cerebral edema and metabolic crisis. PTE is a localization-related epilepsy strongly associated with TBI severity, but risk factors for PTE and epileptogenesis are incompletely understood and are active areas of research. Medical management of PTS in adults and children is reviewed. Surgical options for posttraumatic drug-resistant epilepsy are also discussed.

RECENT FINDINGS

Continuous electroencephalography is indicated for children and adults with TBI and coma because of the high incidence of nonconvulsive seizures, periodic discharges, and associated secondary brain injury in this population. Neuroinflammation is a central component of secondary brain injury and appears to play a key role in epileptogenesis. Levetiracetam is increasingly used for seizure prophylaxis in adults and children, but variability remains.

SUMMARY

PTS occur commonly after TBI and are associated with secondary brain injury and worse outcomes in adults and children. Current medical and surgical management options for PTS and PTE are reviewed.

Outcomes following electrographic seizures and electrographic status epilepticus in the pediatric and neonatal ICUs

PURPOSE OF REVIEW

Increasing recognition of electrographic seizures and electrographic status epilepticus in critically ill neonates and children has highlighted the importance of identifying their potential contributions to neurological outcomes to guide optimal management.

RECENT FINDINGS

Recent studies in children and neonates have found an independent association between increasing seizure burden and worse short-term and long-term outcomes, even after adjusting for other important contributors to outcome such as seizure cause and illness severity. The risk of worse neurological outcome has been shown to increase above a seizure burden threshold of 12-13 min/h, which is considerably lower than the conventional definition of status epilepticus of 30 min/h. Randomized controlled trials in neonates have demonstrated that electroencephalography-targeted therapy can successfully reduce seizure burden, but due to their small size these trials have not been able to demonstrate that more aggressive electroencephalography-targeted treatment of both subclinical and clinical seizures results in improved outcome.

SUMMARY

Despite mounting evidence for an independent association between increasing seizure burden and worse outcome, further study is needed to determine whether early seizure identification and aggressive antiseizure treatment can improve neurodevelopmental outcomes.

Automatic Change Detection for Real-Time Monitoring of EEG Signals

In recent years, automatic change detection for real-time monitoring of electroencephalogram (EEG) signals has attracted widespread interest with a large number of clinical applications. However, it is still a challenging problem. This paper presents a novel framework for this task where joint time-domain features are firstly computed to extract temporal fluctuations of a given EEG data stream; and then, an auto-regressive (AR) linear model is adopted to model the data and temporal anomalies are subsequently calculated from that model to reflect the possibilities that a change occurs; a non-parametric statistical test based on Randomized Power Martingale (RPM) is last performed for making change decision from the resulting anomaly scores. We conducted experiments on the publicly-available Bern-Barcelona EEG database where promising results for terms of detection precision (96.97%), detection recall (97.66%) as well as computational efficiency have been achieved. Meanwhile, we also evaluated the proposed method for real detection of seizures occurrence for a monitoring epilepsy patient. The results of experiments by using both the testing database and real application demonstrated the effectiveness and feasibility of the method for the purpose of change detection in EEG signals. The proposed framework has two additional properties: (1) it uses a pre-defined AR model for modeling of the past observed data so that it can be operated in an unsupervised manner, and (2) it uses an adjustable threshold to achieve a scalable decision making so that a coarse-to-fine detection strategy can be developed for quick detection or further analysis purposes.

Neuroimaging of the Injured Pediatric Brain: Methods and New Lessons

Traumatic brain injury (TBI) is a significant public health problem in the United States, especially for children and adolescents. Current epidemiological data estimate over 600,000 patients younger than 20 years are treated for TBI in emergency rooms annually. While many patients experience a full recovery, for others there can be long-lasting cognitive, neurological, psychological, and behavioral disruptions. TBI in youth can disrupt ongoing brain development and create added family stress during a formative period. The neuroimaging methods used to assess brain injury improve each year, providing researchers a more detailed characterization of the injury and recovery process. In this review, we cover current imaging methods used to quantify brain disruption post-injury, including structural magnetic resonance imaging (MRI), diffusion MRI, functional MRI, resting state fMRI, and magnetic resonance spectroscopy (MRS), with brief coverage of other methods, including electroencephalography (EEG), single-photon emission computed tomography (SPECT), and positron emission tomography (PET). We include studies focusing on pediatric moderate-severe TBI from 2 months post-injury and beyond. While the morbidity of pediatric TBI is considerable, continuing advances in imaging methods have the potential to identify new treatment targets that can lead to significant improvements in outcome.

Traumatic nondisplaced coronal suture fracture causing delayed intracranial hemorrhage in a pediatric patient

Skull fracture after a head injury is relatively common in children younger than 2 years of age. The author reports the case of a 14-month-old girl who sustained a unilateral nondisplaced coronal suture fracture from a fall. She developed delayed intracranial hemorrhage from an underlying dural tear and cortical vein injury. Although an isolated skull fracture in a pediatric trauma patient typically portends a benign clinical course and may not require that the patient be hospitalized, a nondisplaced fracture across the coronal suture can lead to dural tear and intracranial injuries. High vigilance is warranted when evaluating CT images around the suture lines and treating pediatric patients with fractures across the coronal suture.

Chloride Dysregulation, Seizures, and Cerebral Edema: A Relationship with Therapeutic Potential

Pharmacoresistant seizures and cytotoxic cerebral edema are serious complications of ischemic and traumatic brain injury. Intraneuronal Cl^- concentration ([Cl^-]_i) regulation impacts on both cell volume homeostasis and Cl^--permeable GABA_A receptor-dependent membrane excitability. Understanding the pleiotropic molecular determinants of neuronal [Cl^-]_i - cytoplasmic impermeant anions, polyanionic extracellular matrix (ECM) glycoproteins, and plasmalemmal Cl^- transporters - could help the identification of novel anticonvulsive and neuroprotective targets. The cation/Cl^- cotransporters and ECM metalloproteinases may be particularly druggable targets for intervention. We establish here a paradigm that accounts for recent data regarding the complex regulatory mechanisms of neuronal [Cl^-]_i and how these mechanisms impact on neuronal volume and excitability. We propose approaches to modulate [Cl^-]_i that are relevant for two common clinical sequela of brain injury: edema and seizures.

EEG Monitoring and Antiepileptic Drugs in Children with Severe TBI

BACKGROUND

Traumatic brain injury (TBI) causes substantial morbidity and mortality in US children. Post-traumatic seizures (PTS) occur in 11-42% of children with severe TBI and are associated with unfavorable outcome. Electroencephalographic (EEG) monitoring may be used to detect PTS and antiepileptic drugs (AEDs) may be used to treat PTS, but national rates of EEG and AED use are not known. The purpose of this study was to describe the frequency and timing of EEG and AED use in children hospitalized after severe TBI.

METHODS

Retrospective cohort study of 2165 children at 30 hospitals in a probabilistically linked dataset from the National Trauma Data Bank (NTDB) and the Pediatric Health Information Systems (PHIS) database, 2007-2010. We included children (age <18 years old at admission) with linked NTDB and PHIS records, severe (Emergency Department [ED] Glasgow Coma Scale [GCS] <8) TBI, hospital length of stay >24 h, and non-missing disposition. The primary outcomes were EEG and AED use.

RESULTS

Overall, 31.8% of the cohort had EEG monitoring. Of those, 21.8% were monitored on the first hospital day. The median duration of EEG monitoring was 2.0 (IQR 1.0, 4.0) days. AEDs were prescribed to 52.0% of the cohort, of whom 61.8% received an AED on the first hospital day. The median duration of AED use was 8.0 (IQR 4.0, 17.0) days. EEG monitoring and AED use were more frequent in children with known risk factors for PTS. EEG monitoring and AED use were not related to hospital TBI volume.

CONCLUSION

EEG use is relatively uncommon in children with severe TBI, but AEDs are frequently prescribed. EEG monitoring and AED use are more common in children with known risk factors for PTS.

Seizures and the Role of Anticonvulsants After Traumatic Brain Injury

Posttraumatic seizures are a common complication of traumatic brain injury. Posttraumatic epilepsy accounts for 20% of symptomatic epilepsy in the general population and 5% of all epilepsy. Early posttraumatic seizures occur in more than 20% of patients in the intensive care unit and are associated with secondary brain injury and worse patient outcomes. Most posttraumatic seizures are nonconvulsive and therefore continuous electroencephalography monitoring should be the standard of care for patients with moderate or severe brain injury. The literature shows that posttraumatic seizures result in secondary brain injury caused by increased intracranial pressure, cerebral edema and metabolic crisis.

Management of the Pediatric Neurocritical Care Patient

Pediatric neurocritical care is a growing subspecialty of pediatric intensive care that focuses on the management of acute neurological diseases in children. A brief history of the field of pediatric neurocritical care is provided. Neuromonitoring strategies for children are reviewed. Management of major categories of acute childhood central neurologic diseases are reviewed, including treatment of diseases associated with intracranial hypertension, seizures and status epilepticus, stroke, central nervous system infection and inflammation, and hypoxic-ischemic injury.

Variation in seizure prophylaxis in severe pediatric traumatic brain injury

OBJECTIVE Posttraumatic seizure is a major complication following traumatic brain injury (TBI). The aim of this study was to determine the variation in seizure prophylaxis in select pediatric trauma centers. The authors hypothesized that there would be wide variation in seizure prophylaxis selection and use, within and between pediatric trauma centers. METHODS In this retrospective multicenter cohort study including 5 regional pediatric trauma centers affiliated with academic medical centers, the authors examined data from 236 children (age < 18 years) with severe TBI (admission Glasgow Coma Scale score ≤ 8, ICD-9 diagnosis codes of 800.0-801.9, 803.0-804.9, 850.0-854.1, 959.01, 950.1-950.3, 995.55, maximum head Abbreviated Injury Scale score ≥ 3) who received tracheal intubation for ≥ 48 hours in the ICU between 2007 and 2011. RESULTS Of 236 patients, 187 (79%) received seizure prophylaxis. In 2 of the 5 centers, 100% of the patients received seizure prophylaxis medication. Use of seizure prophylaxis was associated with younger patient age (p < 0.001), inflicted TBI (p < 0.001), subdural hematoma (p = 0.02), cerebral infarction (p < 0.001), and use of electroencephalography (p = 0.023), but not higher Injury Severity Score. In 63% cases in which seizure prophylaxis was used, the patients were given the first medication within 24 hours of injury, and 50% of the patients received the first dose in the prehospital or emergency department setting. Initial seizure prophylaxis was most commonly with fosphenytoin (47%), followed by phenytoin (40%). CONCLUSIONS While fosphenytoin was the most commonly used medication for seizure prophylaxis, there was large variation within and between trauma centers with respect to timing and choice of seizure prophylaxis in severe pediatric TBI. The heterogeneity in seizure prophylaxis use may explain the previously observed lack of relationship between seizure prophylaxis and outcomes.

Continuous electroencephalography in pediatric traumatic brain injury: Seizure characteristics and outcomes

BACKGROUND

Traumatic brain injury (TBI) is a major cause of pediatric morbidity and mortality. Secondary injury that occurs as a result of a direct impact plays a crucial role in patient prognosis. The guidelines for the management of severe TBI target treatment of secondary injury. Posttraumatic seizure, one of the secondary injury sequelae, contributes to further damage to the injured brain. Continuous electroencephalography (cEEG) helps detect both clinical and subclinical seizure, which aids early detection and prompt treatment.

OBJECTIVE

The aim of this study was to examine the relationship between cEEG findings in pediatric traumatic brain injury and neurocognitive/functional outcomes.

METHODS

This study focuses on a subgroup of a larger prospective parent study that examined children admitted to a level-1 trauma hospital. The subgroup included sixteen children admitted to the pediatric intensive care unit (PICU) who received cEEG monitoring. Characteristics included demographics, cEEG reports, and antiseizure medication. We also examined outcome scores at the time of discharge and 4-6weeks postdischarge using the Glasgow Outcome Scale - Extended Pediatrics and center-based speech pathology neurocognitive/functional evaluation scores.

RESULTS

Sixteen patients were included in this study. Patients with severe TBI made up the majority of those that received cEEG monitoring. Nonaccidental trauma was the most frequent TBI etiology (75%), and subdural hematoma was the most common lesion diagnosed by CT scan (75%). Fifteen patients received antiseizure medication, and levetiracetam was the medication of choice. Four patients (25%) developed seizures during PICU admission, and 3 patients had subclinical seizures that were detected by cEEG. One of these patients also had both a clinical and subclinical seizure. Nonaccidental trauma was an etiology of TBI in all patients with seizures. Characteristics of a nonreactive pattern, severe/burst suppression, and lack of sleep architecture, on cEEG, were associated with poor neurocognitive/functional outcome.

CONCLUSION

Continuous electroencephalography demonstrated a pattern that associated seizures and poor outcomes in patients with moderate to severe traumatic brain injury, particularly in a subgroup of patients with nonaccidental trauma. Best practice should include institution-based TBI cEEG protocols, which may detect seizure activity early and promote outcomes. Future studies should include examination of individual cEEG characteristics to help improve outcomes in pediatric TBI.

Variation in Anticonvulsant Selection and Electroencephalographic Monitoring Following Severe Traumatic Brain Injury in Children-Understanding Resource Availability in Sites Participating in a Comparative Effectiveness Study

OBJECTIVES

Early posttraumatic seizures may contribute to worsened outcomes after traumatic brain injury. Evidence to guide the evaluation and management of early posttraumatic seizures in children is limited. We undertook a survey of current practices of continuous electroencephalographic monitoring, seizure prophylaxis, and the management of early posttraumatic seizures to provide essential information for trial design and the development of posttraumatic seizure management pathways.

DESIGN

Surveys were sent to site principal investigators at all 43 sites participating in the Approaches and Decisions in Acute Pediatric TBI trial at the time of the survey. Surveys consisted of 12 questions addressing strategies to 1) implement continuous electroencephalographic monitoring, 2) posttraumatic seizure prophylaxis, 3) treat acute posttraumatic seizures, 4) treat status epilepticus and refractory status epilepticus, and 5) monitor antiseizure drug levels.

SETTING

Institutions comprised a mixture of free-standing children's hospitals and university medical centers across the United States and Europe.

SUBJECTS

Site principal investigators of the Approaches and Decisions in Acute Pediatric TBI trial.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Continuous electroencephalographic monitoring was available in the PICU in the overwhelming majority of clinical sites (98%); however, the plans to operationalize such monitoring for children varied considerably. A similar majority of sites report that administration of prophylactic antiseizure medications is anticipated in children (93%); yet, a minority reports that a specified protocol for treatment of posttraumatic seizures is in place (43%). Reported medication choices varied substantially between sites, but the majority of sites reported pentobarbital for refractory status epilepticus (81%). The presence of treatment protocols for seizure prophylaxis, early posttraumatic seizures, posttraumatic status epilepticus, and refractory status epilepticus was associated with decreased reported medications (all p < 0.05).

CONCLUSIONS

This study reports the current management practices for early posttraumatic seizures in select academic centers after pediatric severe traumatic brain injury. The substantial variation in continuous electroencephalographic monitoring implementation, choice of seizure prophylaxis medications, and management of early posttraumatic seizures across institutions was reported, signifying the areas of clinical uncertainty that will help provide focused design of clinical trials. Although sites with treatment protocols reported a decreased number of medications for the scenarios described, completion of the Approaches and Decisions in Acute Pediatric TBI trial will be able to determine if these protocols lead to decreased variability in medication administration in children at the clinical sites.

Traumatic Brain Injury and Neuronal Functionality Changes in Sensory Cortex

Traumatic brain injury (TBI), caused by direct blows to the head or inertial forces during relative head-brain movement, can result in long-lasting cognitive and motor deficits which can be particularly consequential when they occur in young people with a long life ahead. Much is known of the molecular and anatomical changes produced in TBI but much less is known of the consequences of these changes to neuronal functionality, especially in the cortex. Given that much of our interior and exterior lives are dependent on responsiveness to information from and about the world around us, we have hypothesized that a significant contributor to the cognitive and motor deficits seen after TBI could be changes in sensory processing. To explore this hypothesis, and to develop a model test system of the changes in neuronal functionality caused by TBI, we have examined neuronal encoding of simple and complex sensory input in the rat’s exploratory and discriminative tactile system, the large face macrovibrissae, which feeds to the so-called “barrel cortex” of somatosensory cortex. In this review we describe the short-term and long-term changes in the barrel cortex encoding of whisker motion modeling naturalistic whisker movement undertaken by rats engaged in a variety of tasks. We demonstrate that the most common form of TBI results in persistent neuronal hyperexcitation specifically in the upper cortical layers, likely due to changes in inhibition. We describe the types of cortical inhibitory neurons and their roles and how selective effects on some of these could produce the particular forms of neuronal encoding changes described in TBI, and then generalize to compare the effects on inhibition seen in other forms of brain injury. From these findings we make specific predictions as to how non-invasive extra-cranial electrophysiology can be used to provide the high-precision information needed to monitor and understand the temporal evolution of changes in neuronal functionality in humans suffering TBI. Such detailed understanding of the specific changes in an individual patient’s cortex can allow for treatment to be tailored to the neuronal changes in that particular patient’s brain in TBI, a precision that is currently unavailable with any technique.

Imaging and serum biomarkers reflecting the functional efficacy of extended erythropoietin treatment in rats following infantile traumatic brain injury

OBJECTIVE Traumatic brain injury (TBI) is a leading cause of death and severe morbidity for otherwise healthy full-term infants around the world. Currently, the primary treatment for infant TBI is supportive, as no targeted therapies exist to actively promote recovery. The developing infant brain, in particular, has a unique response to injury and the potential for repair, both of which vary with maturation. Targeted interventions and objective measures of therapeutic efficacy are needed in this special population. The authors hypothesized that MRI and serum biomarkers can be used to quantify outcomes following infantile TBI in a preclinical rat model and that the potential efficacy of the neuro-reparative agent erythropoietin (EPO) in promoting recovery can be tested using these biomarkers as surrogates for functional outcomes. METHODS With institutional approval, a controlled cortical impact (CCI) was delivered to postnatal Day (P)12 rats of both sexes (76 rats). On postinjury Day (PID)1, the 49 CCI rats designated for chronic studies were randomized to EPO (3000 U/kg/dose, CCI-EPO, 24 rats) or vehicle (CCI-veh, 25 rats) administered intraperitoneally on PID1-4, 6, and 8. Acute injury (PID3) was evaluated with an immunoassay of injured cortex and serum, and chronic injury (PID13-28) was evaluated with digitized gait analyses, MRI, and serum immunoassay. The CCI-veh and CCI-EPO rats were compared with shams (49 rats) primarily using 2-way ANOVA with Bonferroni post hoc correction. RESULTS Following CCI, there was 4.8% mortality and 55% of injured rats exhibited convulsions. Of the injured rats designated for chronic analyses, 8.1% developed leptomeningeal cyst-like lesions verified with MRI and were excluded from further study. On PID3, Western blot showed that EPO receptor expression was increased in the injured cortex (p = 0.008). These Western blots also showed elevated ipsilateral cortex calpain degradation products for αII-spectrin (αII-SDPs; p < 0.001), potassium chloride cotransporter 2 (KCC2-DPs; p = 0.037), and glial fibrillary acidic protein (GFAP-DPs; p = 0.002), as well as serum GFAP (serum GFAP-DPs; p = 0.001). In injured rats multiplex electrochemiluminescence analyses on PID3 revealed elevated serum tumor necrosis factor alpha (TNFα p = 0.01) and chemokine (CXC) ligand 1 (CXCL1). Chronically, that is, in PID13-16 CCI-veh rats, as compared with sham rats, gait deficits were demonstrated (p = 0.033) but then were reversed (p = 0.022) with EPO treatment. Diffusion tensor MRI of the ipsilateral and contralateral cortex and white matter in PID16-23 CCI-veh rats showed widespread injury and significant abnormalities of functional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD); MD, AD, and RD improved after EPO treatment. Chronically, P13-P28 CCI-veh rats also had elevated serum CXCL1 levels, which normalized in CCI-EPO rats. CONCLUSIONS Efficient translation of emerging neuro-reparative interventions dictates the use of age-appropriate preclinical models with human clinical trial-compatible biomarkers. In the present study, the authors showed that CCI produced chronic gait deficits in P12 rats that resolved with EPO treatment and that chronic imaging and serum biomarkers correlated with this improvement.

Mild traumatic brain injury in children is associated with a low risk for posttraumatic seizures

OBJECT Of the 1.7 million traumatic brain injuries (TBIs) in the US, a third occur in patients under 14 years of age. The rate of posttraumatic epilepsy (PTE) may be as high as 19% after severe pediatric TBI, but the risk for seizures after mild TBI is unknown. Although the rate of seizures after mild TBI may be low, current practice is often driven by high clinical concern for posttraumatic seizures. In this study, the authors evaluated electroencephalography (EEG) results and antiepileptic drug (AED) use in a large cohort of children with mild TBI to estimate the incidence of posttraumatic seizures in this population. METHODS Patients presenting to Children's Hospital of Atlanta for mild TBI from 2010 to 2013 were evaluated. Five thousand one hundred forty-eight patients with mild TBI were studied and divided into 3 groups: 4168 who were discharged from the emergency department, 868 who were admitted without neurosurgical intervention, and 112 who underwent neurosurgical procedures (craniotomy for hematoma evacuation or elevation of depressed skull fractures) but were discharged without an extended stay. Demographic information, CT characteristics, EEG reports, and prescriptions for AEDs were analyzed. Long-term follow-up was sought for all patients who underwent EEG. Correlation between EEG result and AED use was also evaluated. RESULTS All patients underwent head CT, and admitted patients were more likely to have an abnormal study (p < 0.0001). EEG evaluations were performed for less than 1.0% of patients in all 3 categories, without significant differences between groups (p = 0.97). Clinicians prescribed AEDs in less than 2.0% of patients for all groups, without significant differences between groups (p = 0.094). Even fewer children continue to see a neurologist for long-term seizure management. The EEG result had good negative predictive value, but only an abnormal EEG reading that was diagnostic of seizures correlated significantly with AED prescription (p = 0.04). CONCLUSIONS EEG utilization and AED prescription was low in all 3 groups, indicating that seizures following mild TBI are likely rare events. EEG has good negative predictive value for patients who did not receive AEDs, but has poorer positive predictive value for AED use.

Multimodality Neuromonitoring in Pediatric Neurocritical Care: Review of the Current Resources

Brain insults in children represent a daily challenge in neurocritical care. Having a constant grasp on various parameters in the pediatric injured brain may affect the patient's outcome. Currently, new advances provide clinicians with the ability to utilize several modalities to monitor brain function. This multi-modal approach allows real-time information, leading to faster responses in management and furthermore avoiding secondary insults in the injured brain.