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Traumatic brain injury can be classified by severity into mild (Glasgow Coma Scale [GCS] ≥14), moderate (GCS 9–13), and severe (GCS ≤ 8) categories.
An emergent noninfused head computed tomography is the imaging modality of choice in patients with cranial trauma.
Patients with intracranial hemorrhage can quickly deteriorate and require frequent neurological re-evaluations.
Limit secondary brain injury by identifying and addressing concurrent hypoxemia, hypotension, and increased intracranial pressure.
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Between 1.2 and 2 million patients sustain some form of traumatic brain injury (TBI) in the United States every year. Fortunately the majority of cases (~80%) are mild, as moderate and severe TBI is associated with significant long-term disability and death. In fact, head injuries are the leading cause of traumatic death in all patients younger than 25 years. Currently more than 50,000 deaths and 370,000 hospitalizations are attributable to TBI on an annual basis. The associated costs of caring for patients with acute and chronic TBI are astronomical, exceeding $4 billion per year. TBI occurs as the normal physiologic function of the brain is disrupted by either direct (object striking the cranium) or indirect (acceleration/deceleration) forces. Patterns of injury can be classified as either primary (occur at the time of impact) or secondary (develop over time owing to neurochemical and inflammatory responses). Patients with TBI can be further stratified by their Glasgow Coma Scores (GCS) into mild (GCS ≥14), moderate (GCS 9–13), and severe (GCS ≤8) categories (Table 85-1)
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Cerebral circulation is dictated by the cerebral perfusion pressure (CPP), and ensuring adequate blood flow is of the utmost importance in patients with TBI. The CPP is proportional to the difference between the mean arterial pressure (MAP and the intracranial pressure (ICP) (CPP ∝ MAP – ICP). The intracranial space is a fixed volume, and the ICP is determined by the amount of brain tissue, blood, and cerebrospinal fluid (CSF) within it. Increases in either of these variables will cause secondary elevations in the ICP. The brain can autoregulate cerebral perfusion under normal physiologic conditions, but cannot do so at the extremes of either MAP or ICP. Therefore, processes that significantly decrease the MAP (eg, traumatic shock) or increase the ICP (eg, intracranial hemorrhage) may impair cerebral perfusion and exacerbate secondary brain injury.
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The following is a list of specific injury patterns seen in patients with TBI:
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