TRAUMATIC BRAIN INJURY
Traumatic brain injury (TBI) is the leading cause of trauma-related death and disability worldwide, affecting both adult and pediatric populations significantly. The incidence in the United States is estimated at 1.36 million cases with 52,000 deaths, as well as 275,000 hospitalizations annually (Centers for Disease Control and Prevention, 2016). Worldwide, TBI remains the leading cause of morbidity and mortality in those aged younger than 45 years (Andersen, Gazmuri, Marin, Regueira, & Rovegno, 2015). TBI is a common and unfortunate cause of disability and death in infants and children. Unintentional causes of TBI include falls and motor vehicle accidents, while child abuse in infants and young children and assaults in adolescents are inflicted causes of TBI (Su, Raghupathi, & Huh, 2015). TBI encompasses a wide variety of conditions, ranging from mild to life threatening, and can best be described as an alteration in brain function and/or structure because of external forces such as blunt or penetrating trauma, or acceleration/deceleration forces (White & Venkatesh, 2016). Many types of TBI exist, such as concussions, hemorrhages, axonal injuries, and skull fractures to name a few. These injuries may further be designated as acute, subacute, chronic, or acute on chronic. TBIs also include primary and secondary injury classifications. Nursing implications include the assessment, identification of nursing problems, interventions, evaluation, and prevention of these injuries.
TBI is defined as a pathological alteration in the function or structure of the brain by way of external forces. These forces can cause friction of the tissue, tearing of the vessels, or axonal injuries at the cellular level that cause impairment of function. Initial injuries are capable of causing secondary injuries, usually, because of cerebral edema, increased intracranial pressure (ICP), intracranial hypertension, oxidative stress, excitotoxicity, and seizures. Through assessment and intervention, the incidence of secondary brain injuries can be reduced (Andersen et al., 2015).
Prevalence of TBI varies by age. Children younger than 4 years of age, adolescents between 15 and 19 years of age, and adults older than 65 years are those most often diagnosed with TBI. Children younger than 14 years of age constitute approximately half of a million emergency department visits annually. Those older than 75 years are most likely to incur TBI-related hospitalization and death. TBI is a contributing factor to one third of all injury-related deaths in the United States. Mild TBIs constitute a majority of the reported injuries, with no available data on those who suffer mild TBIs and do not seek care. TBI is a costly public health issue, totaling approximately $60 billion per year when accounting for the direct and indirect costs (Centers for Disease Control and Prevention, 2016).
107Mild TBIs, such as concussions, are most prominent at 80% of all TBIs. The leading cause of severe TBI is motor vehicle collisions, accounting for 30% to 50% of head injuries, with males aged 15 to 24 years being the most prominent demographic affected. Other risk factors include participation in contact sports, falls, advanced age (because of polypharmacy and sensory losses related to age), and failure to use safety devices, such as helmets, seat belts, and handrails (Garton & Lehmann, 2015). The structural pathology in TBI includes primary, secondary, Monro–Kellie Doctrine, and Cushing’s triad phenomena.
Primary TBIs include skull fractures, hemorrhages, contusions, and diffuse axonal injury (DAI). Owing to extreme forces required, there exists high suspicion for concomitant cervical spine injury, and care should be taken to immobilize the spine. Skull fractures may require surgery to repair or may be medically managed by observation. Hemorrhages are treated differently, dependent on type and severity. Epidural hemorrhages are arterial, usually arising from a torn temporal artery and usually requiring surgical intervention. Subdural hemorrhages are venous in origin and may require evacuation if there is significant mass effect or deficits noted. Traumatic subarachnoid hemorrhages may require an external ventricular drain (EVD) to be placed to monitor bleeding and ICP monitoring. Contusions and DAI are medically monitored (Garton & Lehmann, 2015).