Head trauma (main)

(Redirected from Blunt head trauma)

This page is for adult patients. For pediatric patients, see: head trauma (peds)

Background

TBI GCS.jpg
  • Also known as Traumatic Brain Injury (TBI): Impairment in brain function from a mechanical force

TBI Pathophysiology

Primary injury

Secondary injury

Brain swelling causes increased ICP which compresses the tissue causing ischemia with direct compression of the vasculature causing brain tissue herniation and brain death

  • Leads to expansion of the original injury (predominantly metabolic insult)
    • Calcium and sodium shifts
    • Mitochondrial damage
    • Production of free radicals
  • Ultimately leads to damage to axonal integrity and axonal transport
    • Enzyme activity leads to apoptosis
  • Microscopic structural injury is often unidentifiable on CT or MRI

Cerebral Blood Flow and Autoregulation

  • vasoconstriction
    • HTN, Hypocarbia, alkalosis
  • No good way to measure cerebral blood flow
    • Use CPP as surrogate
      • CPP is amount of pressure needed to perfuse the brain
      • CPP=MAP-ICP
        • When ICP elevates, CPP decreases
        • Normal ICP
          • 15 in adults
          • <10 to 15 in children
          • 1.5 to 6.0 in infants
  • Autoregulation allows the body to control the cerebral blood flow
    • Autoregulatory mechanism is damaged in most TBI patients

Clinical Features

  • Adult patient with blunt head trauma

Differential Diagnosis

Head trauma

Neck Trauma

Evaluation

Adult GCS

Eye Opening Verbal Motor
6: Obeys commands
5: Oriented 5: Localizes to pain
4: Spontaneously opens 4: Confused speech 4: Withdraws from pain (normal flexion)
3: Opens to command 3:Inappropriate words 3: Decorticate posturing (abnormal flexion)
2: Opens to pain 2: Incomprehensible sounds 2: Decerebrate posturing (extension)
1: Does not open 1: No response 1: No response
  • 14-15: Mild
  • 9-13: Moderate
  • 3-8: Severe

Workup

Workup is dependent on GCS severity, see:

Management & Disposition

Dependent on underlying diagnosis, see:

See Also

References