Traumatic Brain Injury in Pediatrics

Traumatic brain injury is the leading cause of death and disability, and has devastating long-term sequelae and consequences (attributed to age and development potential). Pediatric TBI may affect the scalp, skull, and brain, and differs in pathophysiology and management compared to adults.

Key Characteristics

In children, survival rates are better than adults, the diagnosis is more accurate and treatment is more appropriate, complications can be prevented and long-term outcomes can be predicted. On the downside, it is associated with significant lifetime costs, and among other types of traumatic injuries, it is most likely to result in death and disability.

Pediatric TBI Statistics

• 1035 per 100,000 ER consultations in 0–4 years aged children
• 80 per 100,000 hospitalizations
• Annual death rate 5 per 100,000 in children <4 years
• Death rate higher for children <4 years compared to 5–14 years
• Hospitalization most common in adolescents (129 per 100,000)
• Boys more likely to consult with ER compared to girls
• TBI mechanisms vary according to age (abusive injuries and motor vehicle accidents in children < 4 years; falls in children <14 years).

Types of Head Injuries by Age

The most common forms of TBI in newborns are delivery head injury, cephalic hematoma, subgaleal hematoma, and intracranial hemorrhages. Common forms of TBI in infants are accidental head injury and abusive head trauma [1]. In toddlers and school children, accidental head injury is most common. In adolescents, the head injuries are manifested as bicycle-related injuries, motorcycle related injuries, and sports-related head injuries.

Classification of Injuries (by Nature of Impact Force)

Head injuries may be classified as impactions and impulsions according to the nature of inertial forces [1]. Impact forces are experienced when the head strikes on a surface or when a moving object strikes a head. The injury may be manifested as skull fracture, epidural hematoma, or focal brain lesions. Inertial forces are experienced due to rapid acceleration or deceleration of the brain within the skull resulting in shearing or tearing of the brain tissue or nerve fibers.

Severity Rating for Injuries

The severity rating for injuries is assigned based on duration of loss of consciousness (LOC), extent or nature of injury, post-traumatic amnesia (PTA) or memory loss immediately following injury, or the severity of concussion at initial assessment during the acute phase. TBI can be mild (mTBI), moderate, or severe. mTBI is associated with LOC < 30 minutes, GCS or pediatric GCS 13–15 after 30 minutes of injury onset, and PTA > 24 hours. Uncomplicated mTBI is not accompanied by overt neuroimaging findings. However, complicated TBI is associated with intracranial abnormalities including bruising and blood collection. Moderate TBI is associated with LOC or PTA between 1 and 24 hours and GCS score 9–12. Severe TBI is linked to LOC > 24 hours, PTA > 7 days, and GCS 3–8 [1].

Nature of Damage to Nervous Tissue

TBI causes primary and secondary damage to nervous tissue. Primary damage happens at the time of impact or penetration [1]. Primary TBI may be extra parenchymal injury (subdural hematoma, epidural hematoma, intraventricular hemorrhage, or subarachnoid hemorrhage), intra parenchymal injury (diffuse axonal injury / DAI, intracerebral hemorrhage, or intracerebral hematoma), or vascular injury (carotid artery-cavernous sinus fistula, pseudoaneurysm dural arteriovenous fistula, or vascular dissection). Secondary damage happens as a result of the indirect results of the injury.

Signs and Symptoms of TBI

The signs and symptoms of TBI may be one or more of the following [1]:

• Level of consciousness falling on a spectrum, with loss of consciousness (LOC) on the farther end and prolonged LOC leading to coma
• Vomiting, dizziness, fatigue, headache, pain, nausea
• Seizures, impaired movement, problems with coordination, impaired balance
• Motor speed and programing deficits (i.e. dyspraxia or apraxia), reduced muscle strength (i.e. paralysis or paresis)
• Changes in bowel movement or bladder function
• Problems with cognition, attention, executive function, memory and learning, information processing, and metacognition
• Behavioral and emotional problems
• Feeding and swallowing problems
• Visual, audio-vestibular, speech/language/voice problems

Infants and toddlers may exhibit changes in paying attention, playing habits, eating and sleeping habits, and nursing habits. They may have light and noise sensitivity, lethargy, loss of balance, unsteady walk, persistent crying, irritability, loss of new skills (such as toilet training), and loss of acquired language.

TBI Assessment

Parents may not be able to perceive the immediate consequences of pediatric TBI. In a case of three-year old boy, Ryan being hit by a soccer ball, his dad described the experience as “I knew we need to get to hospital right now and it was very very serious, but I didn’t realize exactly how serious it was.” Ryan was diagnosed with severe TBI [2]. A clinician performs an assessment for pediatric TBI using the Glasgow Coma Scale (GCS) to measure consciousness.

Medical Management

The medical management for pediatric TBI requires close monitoring and control for intracranial pressure and cerebral circulation. Patients may require educational support, environmental modification, and psychological support [1]. Physicians may follow strategies such as large dose of barbiturate, lowering body temperature, and the use of sophisticated devices. Withdrawal from barbiturate and lowering body temperature may lead to behavioral problems, sleep apnea, sleep disturbances, and diminished intellectual function. Outcomes may be manifested as patients not responding to external stimuli depending on severity of damage or may exhibit patterns of gradual and full return to consciousness. A small number of children may remain in coma. Recovery from TBI happens in stages (1) eye opening to external stimuli and generalized responses to noxious stimuli (2) agitated and combative, may not be aware of actions (3) appropriate responses to commands and ability to pay attention and concentrate, recognize family members (4) goal-oriented interventions focusing on function, non-invasive brain stimulation. Rehabilitation requires an interdisciplinary approach entailing stabilizing, preventing secondary complications, physical therapy/occupational therapy/speech therapy/ neuropsychological testing, teaching strategies to compensate for impaired or lost function and optimizing the use of abilities as they return, and partnering with a child’s school services needed for academic achievement in a safe and appropriate manner.

Therefore, even though the survival rates in children are better compared to adults, the long-term consequences can be devastating owing to the development potential in children. Significant costs are involved in caring for a child and may last over the life course, however, appropriate diagnosis, treatment, and prevention of complications can predict positive outcomes.

References

[1] Physiopedia, “Traumatic Brain Injury in Paediatrics,” Physiopedia. Available: https://www.physio-pedia.com/Traumatic_Brain_Injury_in_Paediatrics

[2] A. Children’s, “Recovering from Traumatic Brain Injury: Ryan’s Story,” www.youtube.com, 1999. Available: https://www.youtube.com/watch?v=YpdCspyn4co&pp=ygUWcnlhbiBzb2NjZXIgc2V2ZXJlIHRiaQ%3D%3D