Acute Management of the Brain Injury Patient

SOURCE

Source: Boucher BA, Wood GC. Acute management of the brain injury patient. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 10th ed. New York, NY: McGraw-Hill; 2017. https://accesspharmacy.mhmedical.com/content.aspx?bookid=1861&sectionid=134127799. Accessed February 23, 2019.

CONDITION/DISORDER SYNONYMS

• Traumatic brain injury (TBI)

PATHOPHYSIOLOGY

• Neurologic sequelae of brain trauma can occur as a result of primary or secondary injuries.

  • Primary injuries

    • Contact related (ie, blunt-object blow, penetrating-missile injuries) resulting in skull fractures, brain contusion, hemorrhages

    • Acceleration/deceleration

      • Instantaneous brain movements following motor vehicle accidents

    • Injuries defined as focal (eg, contusions, hematomas) or diffuse

      • Major factor as to which of the secondary injury mechanisms discussed below will predominate following a TBI

  • Secondary neuronal injuries

    • Energy-dependent cellular necrosis due to membrane cell lysis, edema, inflammation, or apoptosis leading to cell shrinkage and cell membrane dissolution

EPIDEMIOLOGY

• TBI is the leading cause of death and disability among children and young adults.

• 1.7 million persons sustain a TBI each year in the United States equating to TBI every 15 s.

• Among these, 275,000 require hospital admission and 53,000 die annually.

• 5.3 million persons currently live with disabilities as a result of their TBI.

• Direct and indirect spending on TBI patients requiring hospitalization of $76.5 billion in the United States in 2010.

CLINICAL PRESENTATION

• General

  • Level of consciousness on admission ranges from awake and alert to completely unresponsive (ie, Glasgow coma scale [GCS] 15–3, respectively)

  • GCS to grade arousal and functional capacity of cerebral cortex

    • Defines level of consciousness according to eye opening, motor response, and verbal response

• GCS scores (Table 1)

  • GCS 15: Normal

  • GCS 3–8: Severe

  • GCS 9–12: Moderate

  • GCS 13–15: Mild or minor brain injuries

• Agents to avoid until initial examination is complete because they affect neurologic examination

  • Opiates, sedatives, neuromuscular blockers

• Rapidly attainable clinical variables predictive of poor outcomes

  • Patient’s age

  • Presence of hypotension

  • Increased intracranial pressure (ICP)

  • Decreased GCS score (especially motor score)

  • Pupillary reactivity

  • Computed tomography (CT) scan (+) for hematoma, subarachnoid hemorrhage, midline shift, and compression of ventricular cisterns

• Signs and symptoms

  • Symptoms: Posttraumatic amnesia (>1 hour), dizziness, moderate to severe headache, nausea/vomiting, limb weakness, paresthesia

  • Signs: Cerebrospinal fluid (CSF) otorrhea or rhinorrhea, seizures, unequal or unreactive pupils indicating more severe injury, rapid deterioration in mental status indicating expansion of lesion within the skull, alteration/unstable vital signs, Cheyne-strokes respiration, tachypnea, hypertension, bradycardia