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• Cerebrum


  Controls speech, intelligence, memory
• Cerebellum


  Controls balance, coordination
• Brain injuries

  Structural injuries
• Cervical and lumbar spine


  • More susceptible to injury
• Third ventricle


  Produces cerebrospinal fluid (CSF)
• There are 31 pairs of spinal nerves
• Spinal nerves


  • Conduct impulses from skin and other organs to the spinal cord
  • Conduct motor impulses from the spinal cord to the muscles
• Cranial nerves


  12 pairs that transmit information directly to and from the brain; perform special functions in the head and face, include sight, smell, taste, hearing, and facial expressions
• Reflex arc

  Connects sensory nerve to motor nerve
• Scalp is very vascular - bleeding may be profuse
• Even small lacerations of scalp can lead to significant blood loss; may be enough to cause hypovolemic shock
• Scalp injuries are often an indicator of deeper, more serious injuries
• Scalp injuries - have a high index of suspicion of skull or brain injury
• Emergency care for scalp injuries

  Support ABCS; control bleeding and dress and bandage; don't apply pressure if there are bone fragments, brain tissues, depression of skull
• Skull fracture signs

  • Deformity, raccoon eyes, and battle sign (bruising below and behind ears)
• Head injuries assessing

  Consider MOI (look at windshield and helmet); consider signs and symptoms such as scalp contusions, hematomas, lacerations, deformity to skull, soft area/depression, penetrating injury, unequal, sluggish, non-responsive pupils, and headaches, loss of consciousness, exposed brain tissue, blood or CSF leaking from ears/nose, seizures, raccoon eyes, battle's sign, dizziness, N/V
• For facial injuries, consider the secondary injuries (brain and spinal cord)
• Primary concern with facial injuries

  Airway obstruction
• Traumatic brain injuries

  The most serious of all head injuries
• Primary (direct) traumatic brain injuries


  Results instantaneously from impact to the head
• Secondary (indirect) traumatic brain injuries

  Increase the severity of primary injuries
• Causes of secondary brain injuries

  • Hypoxia
  • Hypotension
  • Cerebral edema
  • Intracranial hemorrhage
  • Increased ICP
  • Cerebral ischemia
  • Infection
• Coup-contrecoup injury


  Can result from head striking an object
• Cerebral edema may not develop for several hours in traumatic brain injuries
• Low blood oxygen levels aggravate cerebral edema
• Patients with traumatic brain injuries should be monitored for seizure activity
• Concussion


  Closed injury with a temporary loss or alteration of part or all of the brain's abilities to function without demonstrable physical damage to the brain
• About 90% of patients do not experience a loss of consciousness when a concussion occurs
• Symptoms of suspected concussion

  • Dizziness
  • Weakness
  • Visual changes
  • Nausea and vomiting
  • Ringing in the ears
  • Slurred speech
  • Inability to focus
• Contusion


  Involves physical injury to brain tissues; more serious than concussions; may cause long-lasting and even permanent damage
• Intracranial pressure (ICP)


  The accumulation of blood within the skull or swelling of the brain can rapidly lead to an increase in ICP
• Increased ICP squeezes the brain against bony prominences within the cranium, causes hypoxia
• Brain injuries can also arise from medical conditions, such as blood clots or hemorrhages
• Signs and symptoms of nontraumatic injuries are often the same as those of traumatic brain injuries
• Epidural hematoma

  Accumulation of blood between the skull and dura mater; nearly always a result of a blow to the head that produces a linear fracture
• Subdural hematoma

  Accumulation of blood beneath the dura mater but outside the brain; may or may not be skull fracture
• Subarachnoid hematoma

  Accumulation of blood between the pia mater and arachnoid layer; may or may not be skull fracture
• Intracerebral hematoma


  Bleeding within brain tissue itself; can occur following a penetrating injury to the head or because of rapid deceleration forces
• Brain injury - hematoma (mechanism)

  1. Compression of brain stem leads to reduced respiration

  2. Brain becomes O2 starved, high in CO2, leads to increased swelling in the brain

  3. Swelling of the brain may progress to the point where a herniation occurs (tissues leave cavity) into foramen magnum

  4. Vagal stimulation may cause drop in pulse and blood pressure increase
• Signs of increased intracranial pressure

  • Cheyne-Stokes respirations
  • Ataxic (Biot) respirations (deep with interspersed apnea)
  • Decreased pulse rate
  • Headaches
  • Nausea
  • Vomiting
  • Decreased alertness
  • Bradycardia
  • Sluggish or nonreactive pupils
  • Decebrate posturing
  • Increased or widened blood pressure (systolic and diastolic further and further apart)
  • Cushing triad