Head Injury & TBI

Overview of Head Injuries

  • Head injuries can result from blunt or penetrating forces.

  • Classification of injuries includes:

    • Scalp injury

    • Cranial injury

    • Common location for skull fractures is at the base of the skull (basilar skull fracture).

    • Signs and Symptoms (S&S):

      • Battle’s sign

      • Raccoon eyes

      • Note: These can be late signs of serious injury.

    • Traumatic brain injury (TBI)

Traumatic Brain Injury (TBI)

Types of Injuries

  1. Direct (Primary) Injury

    • Resulting from trauma forces (e.g., acceleration and deceleration, penetrating injuries).

    • Coup-Contrecoup injuries

      • Occur due to an initial force followed by the brain impacting the opposite end of the skull.

    • Cerebral Contusion

      • Caused by capillary bleeding into the brain.

    • Epidural Hematoma

      • Bleeding between dura mater and skull, typically from an artery (middle meningeal artery), causing rapid progression of symptoms.

    • Subdural Hematoma

      • Bleeding beneath the dura mater; symptoms may be delayed by hours or days.

    • Intracerebral Hemorrhage

      • Ruptured blood vessel within the brain; often mimics stroke symptoms.

    • Diffuse Injuries

      • Includes concussions or diffuse axonal injury caused by shearing, tearing, or stretching forces on nerve fibers.

  2. Indirect (Secondary) Injury

    • Result of cascading effects from direct injury, such as:

      • Decreased circulation to brain tissue leading to cerebral infarcts.

      • Pressure and structural changes from blood or mass lesions.

    • Clinical effects may include:

      • Cheyne-Stokes respirations: Variations in breathing volumes followed by periods of apnea.

      • Cushing’s Reflex: Manifested by increased blood pressure and decreased heart rate.

Cerebral Herniation Syndrome

  • Occurs with sudden increases in intracranial pressure (ICP) that forces brain portions downward, obstructing cerebrospinal fluid flow and applying pressure to the brainstem.

  • Clinical Signs:

    • Rapidly decreasing level of consciousness leading to coma.

    • Pupil dilation and outward-downward eye deviation on injury side.

    • Paralysis of opposite side limbs (arm and leg) to the injury.

    • Decerebrate posturing.

    • Abnormal motor responses indicating severe brain injury

    • Possible speech impairment or loss, known as aphasia

    • Increased intracranial pressure leading to further neurological deterioration.