Special Populations, Including Pediatric and Geriatric Brain Injury
Two ends of the age spectrum
Pediatric brain injury differs in mechanism, physiology, and trajectory. Abusive head trauma is the leading cause of severe TBI in infants; assess for inconsistent history, retinal hemorrhage, and fractures. The developing brain shows greater plasticity but also greater vulnerability - injury disrupts skills not yet acquired, and deficits may appear later as academic and social demands rise. Rehabilitation is family-centered and school-focused: individualized education plans or 504 accommodations, gradual return-to-learn before return-to-play, and concussion protocols with mandated clearance. Watch for effects on growth, spasticity-related orthopedic deformity (hip subluxation, scoliosis), seizures, and endocrine sequelae. Medication dosing is weight-based and changes with growth.
Geriatric brain injury is dominated by falls and anticoagulation. Ground-level falls in patients on warfarin or direct oral anticoagulants carry high risk of delayed intracranial hemorrhage; reverse anticoagulation and observe or reimage per protocol. Comorbidity - hypertension, diabetes, cardiac disease, prior stroke, cognitive impairment - shapes prognosis, and polypharmacy worsens delirium. Mortality is higher and recovery slower, but age alone should not exclude intensive rehabilitation; use frailty, premorbid function, and goals of care rather than chronologic age. Screen for depression, sleep disturbance, post-injury dementia risk, and address caregiver burden and driving safety.
Traps: assuming childhood plasticity guarantees full recovery; missing abuse in an infant with a 'minor fall'; attributing new confusion in an older adult to 'just aging' instead of a subdural; reversing anticoagulation only after imaging already shows deterioration.
Rule of thumb: in the older adult on an anticoagulant, the scan is not the end of the workup - observation and repeat imaging are.
Worked example: an 82-year-old on apixaban falls, has a normal initial CT, and becomes drowsy eight hours later. Repeat imaging, reverse the anticoagulant, and reassess goals with the family.