JT, a previously healthy 13-year-old female, was struck in the head by a line drive foul ball while playing softball. She had no reported loss of consciousness but appeared dazed and confused according to bystanders. She was transported via squad to the ED with report of one episode of vomiting and complaint of headache. Upon arrival to the ED, JT was opening her eyes to voice and was following commands appropriately; however, she remained confused and amnesic to the event. A Glasgow Coma Score (GCS) of 13 was documented. She had no focal neurologic deficits and physical examination was significant for faint forehead bruising and midline cervical spine tenderness at C3-C4 without palpable step-off. She was placed in a cervical collar and transported to radiology for head computerized tomography (CT) scan due to repeated emesis. The head CT scan was negative for fracture or intracranial hemorrhage. Anterior/posterior, lateral, and odontoid cervical spine films were negative for fracture or malalignment. She was admitted to the Trauma Service for observation and serial neurologic examinations.
The following morning, serial neurologic examinations remained stable and JT was alert and oriented with note of a somewhat flat affect and difficulty completing complex information processing. She continued to experience complaints of nausea and headache, requiring maintenance IV fluids, intermittent IV ondansetron, and ibuprofen. The cervical collar was maintained due to persisting midline neck tenderness and pain with attempted flexion/extension movement. Additionally, she was photophobic, sensitive to noise, and dizzy with ataxic gait. Physical Medicine and Rehabilitation was consulted and physical therapy was initiated. Psychosocial support included Social Service and Child Life to facilitate coping and adjustment due to patient and family frustration regarding recommendation not to return to contact sports for the remainder of the season. On hospital day number two, JT was discharged home in the cervical collar after demonstrating ability to tolerate oral intake and clearance by physical therapy. The parents were educated regarding mild traumatic brain injury (MTBI), headache management, and activity restrictions, including no return to school. School re-entry process was initiated with initial contact to the school to communicate restrictions and to provide education concerning the injury.
Six days postdischarge, JT returned for follow-up evaluation in the Trauma Clinic. JT complained of persisting daily headaches but stated that they were of decreasing frequency, duration, and intensity. Dizziness and photophobia had resolved. She had an improved appetite but limited fluid intake. She was taking acetaminophen once per day in the morning only. Physical examination was unremarkable, the cervical spine was clinically cleared, and the collar was discontinued. The parents expressed apprehension regarding JT's moodiness and irritability, and concern regarding missed school days. JT and her parents were counseled, including reinforcement of MTBI education with emphasis on recovery, activity restrictions with adherence to daily routine, and measures to promote fluid intake.
JT returned to school half days 10 days after discharge. School counselors reported that she appeared depressed and cried easily, which were not normal behaviors. JT conveyed frustration regarding activity restrictions and inability to play softball. Counseling sessions were arranged with the school psychologist and she was referred to the Concussion Clinic for formal recommendations regarding her return to competitive sports. Approximately 3 weeks postinjury, JT returned to the Rehabilitation Clinic where she reported her headaches had ceased and she no longer felt frustration performing every day tasks, but still had difficulty concentrating. Per parent report, moodiness and irritability had resolved. Neuropsychologic testing was arranged. Currently, ongoing evaluation by the Rehabilitation Medicine and Concussion Clinic continues to evaluate JT's symptoms and readiness to return to sports.
Traumatic brain injury (TBI) in children encompasses a broad spectrum of injuries, management practices, and outcomes. Specifically, the subcategory of mild traumatic brain injury (MTBI) challenges the healthcare practitioner due to lack of a standard definition of "mild" and the unique pediatric response to injury. This has resulted in controversy and subsequent variability in evaluation and management of children with MTBI. Healthcare practitioners must provide timely, cost-effective management, yet be cognizant that MTBI can escalate into a more serious healthcare condition. The purpose of this review is to define MTBI, discuss issues impeding evaluation, and to review current literature related to predictors of intracranial injury. Finally, the evaluation and management of children who sustain MTBI based on the Cincinnati Children's Hospital Trauma Service MTBI guideline will be discussed.
A consistent working definition of MTBI is important to guide care, yet currently, there is no one standard inclusive definition for MTBI. The traditional definition of "mild" has been a Glasgow Coma Score (GCS) of 13 to 15. Terms such as subtle, minor, minimal, or concussion are frequently used interchangeably, only adding to the confusion.
Practitioners are challenged to identify those patients at risk for significant intracranial injury and subsequent deterioration.1 Data indicate that 70% to 85% of children evaluated in Emergency Departments who undergo head CT scan are MTBI patients,2,3 yet few patients with MTBI harbor an intracranial injury and even fewer require operative intervention.2,4 Acute management of the MTBI child also requires that the risk of intracranial injury be balanced by the judicious use of CT scan to minimize the adverse effects of even low doses of ionizing radiation,5,6 while decreasing the risk associated with a missed intracranial injury.
Pediatric healthcare practitioners must account for developmental, anatomic, and physiologic factors that contribute to the child's unique response to trauma and risk of injury. Young children are prone to head injury due to a large head-to-body ratio, thinner skull, larger subarachnoid space in which the brain may move freely, and relatively weak neck musculature. Additionally, they are predisposed to delayed cerebral edema resulting from increased cerebral blood flow (hyperemia), and shear injury due to less myelination than adults. The flexible skeletal structure in young children may allow traumatic forces to extend to deeper structures, creating injury without fracture.
Skull fractures occur in 10% to 20% of children with MTBI.7,8 When associated with a dural tear, enlargement of the skull fracture may occur over time, resulting in palpable cranial defect known as a growing skull fracture or leptomeningeal cyst. Although a rare complication with reported incidence of 3%,9 children younger than 3 years should be evaluated over a 2- to 3-month course to monitor head circumference and evaluate for development of cranial defect or swelling. Complicating the evaluation further, preverbal skills of infants and young children impede the child's ability to communicate how they were injured and subjective symptoms of headache, nausea, dizziness, or blurred vision.
Practitioners must be cognizant of these factors for a child may harbor severe underlying injury despite a normal initial neurologic examination. As with the adult, intracranial bleeds may lead to acute change in function or chronic changes resulting in significant morbidity and mortality. Even in the presence of a negative head CT scan, long-term considerations include morbidity related to transient negative sequelae that impact function, cognition, and behavioral problems in which studies have documented delayed sequelae up to 2 years later.7-9 This was observed in the case of JT, where weeks following her injury she continued to exhibit subtle cognitive problems and emotional lability impeding her return to school.
Risk of Intracranial Injury
There are few reliable variables predictive for intracranial hemorrhage in children with MTBI.10 Evidence supports that head CT scan is mandated in patients who present with focal neurologic abnormality,2,3 a GCS of <13,11 deteriorating mental status,12 and infants with physical findings of soft tissue injury or scalp hematoma.2,13 The significance of variables such as headache, nausea, vomiting, altered mental status defined as a GCS of 13 to 14, seizure, or loss of consciousness remains unclear in the literature.2,4,10,13-18 The available literature consists of varied inclusion criteria for MTBI, discrepancies in data collection, and use of diverse statistical parameters across studies contributing to diverse management recommendations.10,17 As a consequence of these inconsistencies, liberal use of head CT scan has been advocated.17,18
Children Younger Than 2 Years
Children younger than 2 years are frequently evaluated based on different criteria than older children with a lower threshold for imaging.13 These children are more prone to skull fractures, which subsequently increase the relative risk for intracranial injury fourfold.3 Additionally, the presence of a scalp hematoma in children younger than 2 years has demonstrated an associated intracranial injury on CT scan 93% of the time.2 Other clinical predictors of intracranial injury in this age group include altered mental status, focal neurologic findings, scalp swelling, and unwitnessed trauma or unclear/inconsistent mechanism of injury.13 In a study by Schutzman et al,13 household falls from heights less than 3 to 4 feet were found to be typically benign. Therefore, children with significant injuries and a history of minor blunt trauma, no explanation for injury, or inconsistent history warrant further evaluation.
MILD TRAUMATIC BRAIN INJURY DEFINED
A formal definition embraced by the Mild TBI Committee of the Head Injury Interdisciplinary Special Interest Group19 states that MTBI is a traumatically induced physiologic disruption of brain function manifested by at least one of the following: (1) brief loss of consciousness that lasts a few seconds to no longer than 30 minutes, (2) no abnormal radiographic findings or focal neurologic findings, (3) traumatic amnesia lasting minutes to a few hours but not more than 24 hours.
The transient disturbance in neurologic function associated with MTBI initiates a variety of symptoms that may be readily apparent or rather subtle. These symptoms may impact physical, cognitive, and behavioral function. Physical symptoms can include headaches, dizziness, fatigue, nausea, vomiting, sensitivity to noise or light, blurred vision/diplopia, and sleep disturbance. For JT, these symptoms were very debilitating over the first few days of her recovery, requiring supportive care. Cognitive impairments include reduced attention, impaired concentration, short-term memory dysfunctions, or delay in complex processing. Behavioral changes may include irritability, emotional lability, depression, or anxiety. As many as 40% to 50% of children experience a range of postconcussive symptoms immediately following MTBI.20 The sequelae from these various symptoms range from minor inconveniences to debilitating situations, causing alarm to parents/caregivers as was encountered with JT. In most cases, symptoms resolve within 3 months of injury; however, a small subset of children may continue to experience symptoms beyond 3 months.21 Children with MTBI and a prior history of head injury or premorbid learning/behavioral difficulties may display adverse outcomes, including hyperactivity, inattention, and behavior problems.21,22
CINCINNATI CHILDREN'S HOSPITAL, TRAUMA SERVICE
The goal in evaluating and treating patients with MTBI is to facilitate safe, uniform, and cost-effective management.11 In 1999, the American Academy of Pediatricians and the American Academy of Family Physicians published "Management of Minor Closed Head Injury in Children."23 The following year, the Eastern Association for the Surgery of Trauma released "Practice Management Guidelines for the Management of Mild Traumatic Brain Injury."11 Inclusion criteria, indications for neuroimaging, disposition, and activity restrictions are addressed. However, there are significant differences in scope (inclusion criteria) and subsequent recommendations for care within these guidelines.
Utilizing AAP/AAFP (1999)23 and EAST (2000)11 guidelines as a foundation, the Trauma Service at Cincinnati Children's Hospital, a Level I Pediatric Trauma Center verified by the American College of Surgeons, integrated current review of the literature and expert opinion to formulate recommendations for care of children with MTBI (see Figure 1). The premise of care is based on the foundation that clinical decision making incorporates best practice to guide care. The MTBI guideline was developed and reviewed by Trauma Surgery attending physicians, nurse practitioners, outpatient nursing, and liaisons from Emergency Medicine and Neurosurgery.
Inclusion criteria for Cincinnati Children's Hospital Trauma Service MTBI guideline are children 1 month through 17 years of age who sustain an acute injury to the head within 24 hours. Mild traumatic brain injury is defined by the absence of a focal neurologic deficit and a GCS of 13 to 15 upon presentation to the ED. In addition, children may have a history of an associated loss of consciousness for up to 5 minutes, amnesia to the event, headache, nausea, vomiting, or seizure. Exclusion criteria include hospitalization due to concurrent injury, suspicion of child abuse or alcohol/drug intoxication, or premorbid health conditions such as bleeding diathesis or neurologic disorder.
Evaluation and Management
All children presenting to the Emergency Department with MTBI warrant a thorough history, physical, and neurologic examination.24 Once the child has been stabilized, a thorough review of systems is performed to further define the degree of injury and to evaluate for associated injuries, especially to the cervical spine.
The GCS or modified GCS for children is the standard method of assessing level of consciousness, which is an important aspect of the initial neurologic assessment. Symptoms of confusion, disorientation, perseveration, or the presence of retrograde or anterograde amnesia are noted. Cranial nerve function, sensory-motor skills, deep tendon reflexes, and gait are also evaluated. Baseline assessment is deemed critical to identify subsequent changes in clinical status.
The child's symptoms and signs are noted, including nausea, vomiting, headache, lethargy, visual changes, irritability, or other pain. A careful history is elicited with attention to time of injury as compared to time of evaluation, mechanism, and history of loss of consciousness or associated seizure. The child's age, past medical history, current medications, and allergies are documented.
Careful examination of the head is performed to identify any tenderness or deformity of the scalp, skull, fontanels, facial bones, oropharynx, and ears. Clinical signs of skull fractures can be subtle and may not be evident upon presentation. Possible signs include palpable skull fracture, retro-auricular bruising (Battle's sign), periorbital bruising (raccoon eyes), hemotympanum, cerebrospinal fluid otorrhea or rhinorrhea.16,23 If a palpable skull deformity is noted, the guideline recommends obtaining a head CT scan; however, skull radiographs may also be considered in children younger than 2 years. Referral to neurosurgery is made for displaced skull fractures greater than 2 mm. The most recent revision of the guideline incorporates otolaryngology consultation for any abnormalities in the ear canal or if concern for facial asymmetry. This is necessary to further evaluate for tympanic perforation, external auditory canal laceration, hearing loss (conductive or sensory-neural), or cranial nerve VII injury.
Although the guideline excludes any child in which there is high suspicion for nonaccidental trauma, many infants and toddlers present with a history of fall or being dropped. As nonaccidental trauma accounts for 10% of head injuries in children,25 careful assessment is imperative to rule out this mechanism. At Cincinnati Children's, trauma nurse practitioners identified disparity in care with some patients undergoing skeletal surveys, many of whom had no social service consultation. Subsequently, the guideline incorporates a social service consult for any child younger than 1 year, regardless of mechanism of injury, to promote patient safety and consistency in care.
Drug and alcohol intoxication in relation to MTBI has not been well studied in pediatrics; however, it may be associated with an increased risk of intracranial injury.4 Based on clinician judgment, drug and alcohol screen may be warranted for children 14 years and older.
Skull radiographs have a limited role in the diagnosis of MTBI. Studies indicate that although skull radiographs are 94% to 99% sensitive for detecting skull fractures,3,26 they have a low sensitivity for predicting intracranial injury.8 Computerized tomography scan is the current imaging modality of choice to evaluate TBI,16 however, the presence of a normal CT scan cannot exclude an MTBI. Drawbacks particular to pediatrics include transport of the child away from a supervised ED, radiation exposure,5 associated risk of sedation if needed, and cost.27 Magnetic resonance imaging is only utilized as a diagnostic measure when the CT scan is unable to explain the clinical picture.
Indication for Computerized Tomography
The staff is cautioned to recognize that the determination to obtain imaging studies requires integration of knowledge and understanding of current evidence-based recommendations as well as careful clinical judgment. This is of particular importance when considering isolated symptoms of amnesia to the event, confusion, irritability, and vomiting. In isolation, these symptoms do not mandate head CT scan but collectively may necessitate CT. Progression of symptoms since time of injury, such as worsening headache or multiple episodes of vomiting, may direct further clinical decisions. Head CT scan is recommended for children who exhibit a focal neurologic deficit, loss of consciousness greater than 5 minutes, uncertain history, physical evidence of skull fracture, or anterograde/retrograde amnesia. In the presence of deteriorating mental status, CT scan is mandated. Trauma Service guidelines specify that any child with a positive head CT scan defined by the presence of an intracranial bleed, basilar skull fracture, displaced skull fracture, temporal bone fracture, or facial fractures, exits the MTBI guideline with specialty consultation as indicated.
Appropriate disposition may include release to home, ED observation, or inpatient hospitalization. Patients who do not undergo head CT scan or in the presence of a negative CT scan are discharged to home if the child has a normal neurologic exam, tolerates oral intake, and has a reliable caregiver who has been appropriately educated about MTBI. Timeframe for ED observation may vary based upon the child's clinical exam and symptoms; however, ED observation for all children younger than 2 years for 4 to 6 hours is recommended.13
Inpatient hospitalization may be indicated even in the presence of a negative head CT scan. For instance, inpatient observation is recommended for children with persisting emesis or altered mental status, or concern regarding disposition and ability of caregiver to monitor for change in clinical status. Orders include serial neurologic exams to evaluate for change in clinical status. The child who displays a decline in neurologic status or exhibits seizure activity must exit the MTBI guideline and is treated with urgent evaluation, repeat head CT scan, and consults as indicated. Patients with stable or improving neurologic exam have their diet advanced as tolerated, although management of persisting vomiting may require intravenous fluids and/or antiemetics until the child is able to tolerate oral feeds. Zofran (ondansetron) is preferred rather than phenergan due to less sedating effects that may mask neurologic exam. Serial head circumference for infants and young children with scalp hematomas and serial CBC (hemoglobin and hematocrit) are obtained due to potential for significant blood loss. Acute headache management includes attention to change in degree and severity, administration of analgesia, and environmental measures such as a quiet, calm milieu. Once stable, physical therapy is consulted for children with ataxia or significant dizziness to facilitate safe mobility and gait training. Consultation by Child Life, Chaplain, and Social Service is advocated for all patients to facilitate psychosocial support and coping. Referral to Physical Medicine and Rehabilitation is obtained for children who continue to display altered mental status, delay in complex processing, or amnesia to identify patients at high risk for subtle cognitive deficits. Frequently, follow-up evaluation within 4 weeks is recommended to evaluate the need for formal neuropsychologic testing. School re-entry is facilitated for all patients to promote transition back to school. Teachers are contacted by the outpatient trauma nurse either by telephone or fax to address MTBI education, including signs, symptoms, and activity restrictions. If a school visit is arranged, the trauma nurse practitioner visits the injured child's classroom to discuss the injury with classmates. This provides opportunity to facilitate return to school, with an emphasis on age-appropriate injury prevention activities.
Regardless of ED disposition, appropriate patient/family education is imperative.24 The provision of information about expected symptoms, likely time course, and how best to cope with them can result in significantly reduced report of symptoms and behavioral changes 3 months after injury.21 Appropriate education can minimize stress in children and parents, optimize early management, and reduce attribution of preexisting problems to the injury.21 Specific instructions regarding signs and symptoms requiring medical follow-up, return to activity and sports, and symptom management are addressed by the nursing staff. This opportune time allows health professionals to also address age-appropriate injury prevention. Resources at Cincinnati Children's Hospital include the bicycle helmet and car seat programs that provide helmet or car seats at reduced cost or for free for children who meet established criteria. These programs are designed not only to raise awareness of the importance of injury prevention but to demonstrate the correct use of these devices. Nationwide injury prevention resources include organizations such as Safe Kids Worldwide (previously known as The National Safe Kids Campaign), Children's Safety Network, National Center for Injury Prevention and Control at the CDC, and Consumer Product Safety Commission.
Headaches are not uncommon following MTBI. Within the MTBI guideline, acute management focuses on analgesia and restricted activity as was the case with JT. Prior to discharge from Cincinnati Children's, the parents and the child were educated about the importance of healthy habits, including sleep and nutrition. A minimum of eight (8 oz) glasses/day are encouraged, particularly sports drinks such as Gatorade to replenish fluid and electrolytes. Analgesia with acetaminophen is recommended. Ibuprofen is not recommended more than three times per week due to potential for withdrawal and "rebound" headaches.28
Return to school and sports are important considerations that are discussed with patients and families. Criteria to return to school take into account the degree of symptoms the child is experiencing, however, it does not mean that the child should be asymptomatic to return. If symptoms are debilitating, then criteria for return to school are addressed with the parent and school. Guidelines for safe return to sports consider the cumulative effects of repetitive MTBI29 and risk of second impact syndrome. Second impact syndrome is a rare but fatal consequence of repeat head injury in which the individual sustains a second head injury before signs and symptoms of the first head injury have resolved. It is believed that vasospasm and sudden edema cause a rapid increase in intracranial pressure, resulting in death.30,31
Numerous guidelines have been proposed that characterize the degree of concussion and return to play criteria. Variables are typically based on duration of confusion and post-traumatic amnesia, presence of loss of consciousness, and history of prior concussion. At Cincinnati Children's Hospital, guidelines from the American Academy of Neurology32 are advocated. Other well-known guidelines include those from Cantu33 and the Eastern Association for the Surgery of Trauma.11 In general, consensus is that a child should not return to play until asymptomatic and following a complete physical.
Follow-up evaluation is recommended 1 to 2 weeks postdischarge. Patients returning to the Trauma Clinic are evaluated for symptoms of postconcussion sequelae. Symptoms may be exacerbated by stress, depression, or anxiety and can cause significant psychosocial problems for the child and family, both at home and in school. Interventions include proactive patient and family education, provision of support and counseling, and referral to Physical Medicine and Rehabilitation for appropriate evaluation and neuropsychologic testing if indicated, as was appropriately done in JT's care. Research has demonstrated the value of neuropsychologic testing to help delineate the presence of underlying deficits associated with the injury.34 Referral to the Cincinnati Children's Concussion Clinic is made for athletes wanting to return to sports. In this specialty clinic, Sports Medicine utilizes neurodiagnostic techniques such as magnetic resonance imaging,35 electrophysiological measures,36,37 and postural stability testing,38 as indicated to evaluate persistent effects of MTBI, and addresses recommendations for return to sports. Patients who exhibit persisting headaches hindering function or return to school are referred to the Headache Clinic. This multidisciplinary team of neurologists, psychologists, and nurses treat headache disorders using treatment strategies such as abortive therapy, preventive therapy, and behavioral medicine. The ultimate goal is to optimize function and return to activities of daily living.
As demonstrated in the case study, MTBI can lead to serious physical, cognitive, and behavioral sequelae that impact daily life. JT had persisting complaints of impaired concentration and headaches that ultimately required ongoing evaluation by specialty services to facilitate her recovery. Often, these symptoms are temporary and rarely produce long-term negative outcomes, but can be very worrisome for families in the acute stage. For JT, her primary concern was addressing when she could resume contact sports. Support and education were imperative to promote understanding of associated negative outcomes of repetitive head injury.
Children with seemingly mild head trauma can present perplexing problems for healthcare practitioners. Dilemmas arise as to who is at risk for intracranial injury, indications for diagnostic imaging, disposition, recognition of post-traumatic sequelae, indications for specialty referral, and recommendations for return to sports, and even school. Until consensus is reached as to the standardized definition of MTBI, controversies will persist.
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