Epilepsy associated with shaken baby syndrome

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.

Pediatric traumatic brain injury and abusive head trauma

Childhood traumatic brain injury (TBI) commonly occurs during brain development and can have direct, immediately observable neurologic, cognitive, and behavioral consequences. However, it can also disrupt subsequent brain development, and long-term outcomes are a combination of preinjury development and abilities, consequences of brain injury, as well as delayed impaired development of skills that were immature at the time of injury. There is a growing number of studies on mild TBI/sport-related concussions, describing initial symptoms and their evolution over time and providing guidelines for effective management of symptoms and return to activity/school/sports. Mild TBI usually does not lead to long-term cognitive or academic consequences, despite reports of behavioral/psychologic issues postinjury. Regarding moderate to severe TBI, injury to the brain is more severe, with evidence of a number of detrimental consequences in various domains. Patients can display neurologic impairments (e.g., motor deficits, signs of cerebellar disorder, posttraumatic epilepsy), medical problems (e.g., endocrine pituitary deficits, sleep-wake abnormalities), or sensory deficits (e.g., visual, olfactory deficits). The most commonly reported deficits are in the cognitive-behavioral field, which tend to be significantly disabling in the long-term, impacting the development of autonomy, socialization and academic achievement, participation, quality of life, and later, independence and ability to enter the workforce (e.g., intellectual deficits, slow processing speed, attention, memory, executive functions deficits, impulsivity, intolerance to frustration). A number of factors influence outcomes following pediatric TBI, including preinjury stage of development and abilities, brain injury severity, age at injury (with younger age at injury most often associated with worse outcomes), and a number of family/environment factors (e.g., parental education and occupation, family functioning, parenting style, warmth and responsiveness, access to rehabilitation and care). Interventions should identify and target these specific factors, given their major role in postinjury outcomes. Abusive head trauma (AHT) occurs in very young children (most often <6 months) and is a form of severe TBI, usually associated with delay before appropriate care is sought. Outcomes are systematically worse following AHT than following accidental TBI, even when controlling for age at injury and injury severity. Children with moderate to severe TBI and AHT usually require specific, coordinated, multidisciplinary, and long-term rehabilitation interventions and school adaptations, until transition to adult services. Interventions should be patient- and family-centered, focusing on specific goals, comprising education about TBI, and promoting optimal parenting, communication, and collaborative problem-solving.

Etiological assessment of status epilepticus

Status epilepticus (SE) is a potentially serious condition that can affect vital and functional prognosis and requires urgent treatment. Etiology is a determining factor in the patient's functional outcome and in almost half of all cases justifies specific treatment to stop progression. Therefore, identifying and addressing the cause of SE is a key priority in SE management. However, the etiology can be difficult to identify among acute and remote causes, which can also be multiple and interrelated. The most common etiologies are the discontinuation of antiepileptic medication in patients with a prior history of epilepsy, and acute brain aggression in cases of new onset SE (cerebrovascular pathologies are the most common). The list of remaining possible etiologies includes heterogeneous pathological contexts. Refractory SE and especially New-Onset Refractory Status Epilepticus (NORSE) lead to an extension of the etiological assessment in the search for encephalitis of autoimmune or infectious origin in adults and in children, as well as a genetic pathology in children in particular. This is an overview of current knowledge of SE etiologies and a pragmatic approach for carrying out an etiological assessment based on the following steps: - Which etiological orientation is identified according to the field and clinical presentation?; - Which etiologies to look for in an inaugural SE?; - Which first-line assessment should be carried out? The place of the biological, EEG and imaging assessment is discussed; - Which etiologies to look for in case of refractory SE?

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.

Seizure Severity Is Correlated With Severity of Hypoxic-Ischemic Injury in Abusive Head Trauma

BACKGROUND

The objective of this study was to characterize hypoxic-ischemic injury and seizures in abusive head trauma.

METHODS

We studied 58 children with moderate or severe traumatic brain injury due to abusive head trauma. Continuous electroencephalograms and magnetic resonance images were scored.

RESULTS

Electrographic seizures (51.2%) and hypoxic-ischemic injury (77.4%) were common in our cohort. Younger age was associated with electrographic seizures (no seizures: median age 13.5 months, interquartile range five to 25 months, versus seizures: 4.5 months, interquartile range 3 to 9.5 months; P = 0.001). Severity of hypoxic-ischemic injury was also associated with seizures (no seizures: median injury score 1.0, interquartile range 0 to 3, versus seizures: 4.5, interquartile range 3 to 8; P = 0.01), but traumatic injury severity was not associated with seizures (no seizures: mean injury score 3.78 ± 1.68 versus seizures: mean injury score 3.83 ± 0.95, P = 0.89). There was a correlation between hypoxic-ischemic injury severity and seizure burden when controlling for patient age (r_s=0.61, P < 0.001). The ratio of restricted diffusion volume to total brain volume (restricted diffusion ratio) was smaller on magnetic resonance imaging done early (median restricted diffusion ratio 0.03, interquartile range 0 to 0.23 on magnetic resonance imaging done within two days versus median restricted diffusion ratio 0.13, interquartile range 0.01 to 0.43 on magnetic resonance imaging done after two days, P = 0.03).

CONCLUSIONS

Electrographic seizures are common in children with moderate to severe traumatic brain injury from abusive head trauma, and therefore children with suspected abusive head trauma should be monitored with continuous electroencephalogram. Severity of hypoxic-ischemic brain injury is correlated with severity of seizures, and evidence of hypoxic-ischemic injury on magnetic resonance imaging may evolve over time. Therefore children with a high seizure burden should be reimaged to evaluate for evolving hypoxic-ischemic injury.

The Anesthesiologist's Role in Treating Abusive Head Trauma

Abusive head trauma (AHT) is the most common cause of severe traumatic brain injury (TBI) in infants and the leading cause of child abuse-related deaths. For reasons that remain unclear, mortality rates after moderate AHT rival those of severe nonintentional TBI. The vulnerability of the developing brain to injury may be partially responsible for the poor outcomes observed after AHT. AHT is mechanistically more complex than nonintentional TBI. The acute-on-chronic nature of the trauma along with synergistic injury mechanisms that include rapid rotation of the brain, diffuse axonal injury, blunt force trauma, and hypoxia-ischemia make AHT challenging to treat. The anesthesiologist must understand the complex injury mechanisms inherent to AHT, as well as the pediatric TBI treatment guidelines, to decrease the risk of persistent neurologic disability and death. In this review, we discuss the epidemiology of AHT, differences between AHT and nonintentional TBI, the severe pediatric TBI treatment guidelines in the context of AHT, anesthetic considerations, and ethical and legal reporting requirements.

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

OBJECT Seizures may cause diagnostic confusion and be a source of metabolic stress after traumatic brain injury (TBI) in children. The incidence of electroencephalography (EEG)-confirmed seizures and of subclinical seizures in the pediatric population with TBI is not well known. METHODS A routine protocol for continuous EEG (cEEG) monitoring was initiated for all patients with moderate or severe TBI at a Level 1 pediatric trauma center. Over a 3.5-year period, all patients with TBI who underwent cEEG monitoring, both according to protocol and those with mild head injuries who underwent cEEG monitoring at the discretion of the treating team, were identified prospectively. Clinical data were collected and analyzed. RESULTS Over the study period, 594 children were admitted with TBI, and 144 of these children underwent cEEG monitoring. One hundred two (71%) of these 144 children had moderate or severe TBI. Abusive head trauma (AHT) was the most common mechanism of injury (65 patients, 45%) in children with cEEG monitoring. Seizures were identified on cEEG in 43 patients (30%). Forty (93%) of these 43 patients had subclinical seizures, including 17 (40%) with only subclinical seizures and 23 (53%) with both clinical and subclinical seizures. Fifty-three percent of patients with seizures experienced status epilepticus. Age less than 2.4 years and AHT mechanism were strongly correlated with presence of seizures (odds ratios 8.7 and 6.0, respectively). Those patients with only subclinical seizures had the same risk factors as the other groups. The presence of seizures did not correlate with discharge disposition but was correlated with longer hospital stay and intensive care unit stay. CONCLUSIONS Continuous EEG monitoring identifies a significant number of subclinical seizures acutely after TBI. Children younger than 2.4 years of age and victims of AHT are particularly vulnerable to subclinical seizures, and seizures in general. Continuous EEG monitoring allows for accurate diagnosis and timely treatment of posttraumatic seizures, and may mitigate secondary injury to the traumatized brain.

Long-term outcome of abusive head trauma

Abusive head trauma is a severe inflicted traumatic brain injury, occurring under the age of 2 years, defined by an acute brain injury (mostly subdural or subarachnoidal haemorrhage), where no history or no compatible history with the clinical presentation is given. The mortality rate is estimated at 20-25% and outcome is extremely poor. High rates of impairments are reported in a number of domains, such as delayed psychomotor development; motor deficits (spastic hemiplegia or quadriplegia in 15-64%); epilepsy, often intractable (11-32%); microcephaly with corticosubcortical atrophy (61-100%); visual impairment (18-48%); language disorders (37-64%), and cognitive, behavioral and sleep disorders, including intellectual deficits, agitation, aggression, tantrums, attention deficits, memory, inhibition or initiation deficits (23-59%). Those combined deficits have obvious consequences on academic achievement, with high rates of special education in the long term. Factors associated with worse outcome include demographic factors (lower parental socioeconomic status), initial severe presentation (e.g., presence of a coma, seizures, extent of retinal hemorrhages, presence of an associated cranial fracture, extent of brain lesions, cerebral oedema and atrophy). Given the high risk of severe outcome, long-term comprehensive follow-up should be systematically performed to monitor development, detect any problem and implement timely adequate rehabilitation interventions, special education and/or support when necessary. Interventions should focus on children as well as families, providing help in dealing with the child's impairment and support with psychosocial issues. Unfortunately, follow-up of children with abusive head trauma has repeatedly been reported to be challenging, with very high attrition rates.

Association between infantile spasms and nonaccidental head injury

Infantile spasms constitute a severe epileptic encephalopathy of infancy with poor long-term developmental outcome. Many diverse etiologies have been associated with infantile spasms, but the pathophysiological process is still not fully understood. We describe 2 cases of previously healthy 1- and 3-month-old infants who suffered a nonaccidental head injury with extensive cerebral lesions. Both presented with acute focal seizures rapidly controlled with phenobarbital. Nevertheless, they developed infantile spasms after a latency period of 3-4 months. Spasms were rapidly controlled with vigabatrin. Both children manifested with developmental delay, either exacerbated (case 1) or elicited (case 2) by infantile spasms. Our report highlights nonaccidental head injury as a risk factor for developing infantile spasms following a seizure-free latency period. A better understanding of the pathophysiology linking accidental brain trauma with infantile spasms could lead to more effective neuroprotective strategies. In the meantime, increased awareness and follow-up are warranted.

Surgical options for treatment of traumatic subdural hematomas in children younger than 2 years of age

OBJECT

Subdural hematoma (SDH) is the most common finding on cranial CT in pediatric victims of abusive head trauma (AHT). The hematomas are commonly bilateral and sometimes associated with interhemispheric hyperdensity and/or convexity hemorrhages. There is no consensus regarding the best surgical treatment in such cases nor are there standardized surgical protocols. The authors report their experience and discuss the routine surgical options in the management of traumatic SDH at a Level 1 Pediatric Trauma Center.

METHODS

In this paper, the authors describe a cross-sectional study with consecutive revision of data described in the medical records of Hôpital Universitaire Necker-Enfants Malades between January 2008 and January 2013. During this period, all children younger than 2 years of age who were admitted with a traumatic SDH identified on CT scans were included in this study.

RESULTS

One hundred eighty-four children who had SDH and were younger than 2 years of age were included. Their median age was 5.8 months (range 5 days-23 months), and 70% of the children were male. On admission CT scans, the SDH was bilateral in 52% of cases and homogeneously hypodense in 77%. Neurosurgical treatment was undertaken in 111 children (60%) with an admission Glasgow Coma Scale score of 12 or less, bulging fontanels, or other signs suggestive of intracranial hypertension. The first surgical option was craniotomy in 1.8% (2) of these 111 cases, decompressive craniectomy in 1.8% (2), transcutaneous subdural puncture in 15% (17), external subdural drainage in 16% (18), subdural-subgaleal shunt placement in 17% (19), and subdural-peritoneal shunt placement in 48% (53). In 82% of the children initially treated with transcutaneous subdural puncture and in 50% of those treated with external subdural drainage, increase or persistence of the SDH, CSF or skin infection, or shunt system malfunction was observed and further surgical intervention was required. There was a 26% rate of complications in patients initially treated with a subdural-peritoneal shunt. Although 52% of the patients had bilateral SDH, bilateral drainage was only required in 9.4%.

CONCLUSIONS

The choice of treatment should be determined by the clinical and radiological characteristics of the individual case. Although effective on an emergency basis, subdural puncture and external subdural drainage are frequently insufficient to obtain complete resolution of SDH, and temporary placement of a subdural-peritoneal shunt is needed in most cases.

Nonconvulsive electrographic seizures are common in children with abusive head trauma*

OBJECTIVE

To determine the prevalence of nonconvulsive seizures in children with abusive head trauma.

DESIGN

Retrospective study of children with abusive head trauma undergoing clinically indicated continuous electroencephalographic monitoring.

SETTING

PICU of a tertiary care hospital.

SUBJECTS

Children less than or equal to 2 years old with evidence of abusive head trauma determined by neuroimaging, physical examination, and determination of abuse by the Child Protection Team.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thirty-two children with abusive head trauma were identified with a median age of 4 months (interquartile range 3, 5.5 months). Twenty-one of 32 children (66%) underwent electroencephalographic monitoring. Those monitored were more likely to have a lower admission Glasgow Coma Scale (8 vs 15, p = 0.05) and be intubated (16 vs 2, p = 0.002). Electrographic seizures occurred in 12 of 21 children (57%) and constituted electrographic status epilepticus in 8 of 12 children (67%). Electrographic seizures were entirely nonconvulsive in 8 of 12 children (67%). Electroencephalographic background category (discontinuous and slow-disorganized) (p = 0.02) and neuroimaging evidence of ischemia were associated with the presence of electrographic seizures (p = 0.05). Subjects who had electrographic seizures were no more likely to have clinical seizures at admission (67% electrographic seizures vs 33% none, p = 0.6), parenchymal imaging abnormalities (61% electrographic seizures vs 39% none, p = 0.40), or extra-axial imaging abnormalities (56% electrographic seizures vs 44% none, p = 0.72). Four of 21 (19%) children died prior to discharge; none had electrographic seizures, but all had attenuated-featureless electroencephalographic backgrounds. Follow-up outcome data were available for 16 of 17 survivors at a median duration of 9.5 months following PICU admission, and the presence of electrographic seizures or electrographic status epilepticus was not associated with the Glasgow Outcome Scale score (p = 0.10).

CONCLUSIONS

Electrographic seizures and electrographic status epilepticus are common in children with abusive head trauma. Most seizures have no clinical correlate. Further study is needed to determine whether seizure identification and management improves outcome.

Abnormal neuroimaging is associated with early in-hospital seizures in pediatric abusive head trauma

BACKGROUND

Abusive head trauma (AHT) is a common condition in children. Little is known in this condition regarding the frequency of seizures, the factors associated with increased risk of seizures, or the association of seizures with outcome. We sought to determine frequency and risks for in-hospital seizures after AHT.

METHODS

This was a single-center, retrospective chart review study at a 270 bed tertiary care referral pediatric hospital.

RESULTS

A total of 54 cases of AHT were identified during the study period. During the first week following hospital admission, 33% of patients were observed to have clinical seizures. The occurrence of clinical seizures after admission was associated with findings on initial CT including midline shift, cerebral edema, and loss of gray white differentiation. MRI findings associated with clinical seizures after admission included midline shift, cerebral edema, infarction, and restricted diffusion. The presenting complaint of seizures or acute mental status changes well as a variety of abnormal imaging findings including gray white blurring, infarction, and edema were associated with short-term outcomes.

CONCLUSIONS

Specific neuroradiologic findings identify children at greater risk for seizures, both clinical and subclinical, following AHT. Clinical and subclinical seizures are common in the initial hospitalization for AHT.

Shaken baby syndrome: a common variant of non-accidental head injury in infants

BACKGROUND

Recent cases of child abuse reported in the media have underlined the importance of unambiguous diagnosis and appropriate action. Failure to recognize abuse may have severe consequences. Abuse of infants often leaves few external signs of injury and therefore merits special diligence, especially in the case of non-accidental head injury, which has high morbidity and mortality.

METHODS

Selective literature review including an overview over national and international recommendations.

RESULTS

Shaken baby syndrome is a common manifestation of non-accidental head injury in infancy. In Germany, there are an estimated 100 to 200 cases annually. The characteristic findings are diffuse encephalopathy and subdural and retinal hemorrhage in the absence of an adequate explanation. The mortality can be as high as 30%, and up to 70% of survivors suffer long-term impairment. Assessment of suspected child abuse requires meticulous documentation in order to preserve evidence as well as radiological, ophthalmological, laboratory, and forensic investigations.

CONCLUSIONS

The correct diagnosis of shaken baby syndrome requires understanding of the underlying pathophysiology. Assessment of suspected child abuse necessitates painstaking clinical examination with careful documentation of the findings. A multidisciplinary approach is indicated. Continuation, expansion, and evaluation of existing preventive measures in Germany is required.

Abusive head trauma in infants and young children: a unique contributor to developmental disabilities

Abusive head trauma in infants and young children is the leading cause of death and disability from child abuse. This article discusses the history, epidemiology, clinical aspects, developmental outcomes, and associated injuries of this unique contributor to developmental disabilities. Prevention of abusive injuries and prevention of child abuse and neglect are also discussed.