Spine Injuries and Neurological Trauma

Spine Injuries and Nervous System Overview

Nervous System

• Complex and interconnected network of nerve cells.
• Includes the brain, spinal cord, nerves, and nerve fibers.
• Well-protected but sensitive to injuries.

Anatomic Divisions

• Central Nervous System (CNS): Brain and spinal cord.
• Peripheral Nervous System (PNS):
  • Conducts sensory (fingers to spinal cord) and motor (spinal cord to fingers) impulses.
  • Sensory = sensation needs to be processed.
  • Motor = physical response.

Brain Divisions

• Cerebrum:
  • Largest part, about 75% of brain volume.
  • Divided into two hemispheres and four lobes.
  • Frontal lobe: Higher cognition, personality, emotions.
  • Temporal lobe: Language.
  • Occipital lobe: Visual processing.
• Cerebellum: Base of the skull.
• Brain Stem:
  • Controls basic life functions (cardiac, respiratory, nerve functions).
  • "Lizard brain."

Spinal Cord

• Fibers extending from brain nerve cells.
• Extends to mid-thoracic vertebrae.

Protection Layers

• Bony structures (skull and vertebral bodies).
• Meninges: Three layers of tissue suspending the brain and spinal cord within the spinal canal.
  • Dura Mater: Tough, fibrous outer layer forming a protective sac.
  • Arachnoid Mater & Pia Mater: Inner layers containing blood vessels nourishing the brain and spinal cord.
• Cerebrospinal Fluid (CSF):
  • Produced in ventricles inside the brain.
  • Protects the brain by acting as a shock absorber.
  • CSF leaks (nose, ears) indicate penetrated protective layers.
  • Approximately 125-150 mL of CSF in the brain at any time; even a small leak can be significant.

Peripheral Nerves

• 31 pairs of spinal nerves conduct impulses between skin/organs and the brain.
• 12 pairs of cranial nerves extend directly from the cranium, controlling senses (hearing, vision, smell), facial expressions.
• Two types of peripheral nerves:
  • Sensory nerves.
  • Motor nerves.

Reflexes

• Spinal cord reflexes (e.g., withdrawal reflex) bypass the brain for quick responses.

Nervous System Activities

• Controls reflexes (spinal cord).
• Voluntary activities.
• Involuntary activities.

Autonomic Nervous System

• Handles involuntary activities.
• Two divisions:
  • Sympathetic: Fight or flight response (increased heart rate, blood pressure; decreased digestive activity).
  • Parasympathetic: Rest and digest (homeostasis).

Homeostasis

• The body's goal is to maintain homeostasis.

Skull and Spine Anatomy

Skull

• Four major bones: Occipital, temporal, parietal, frontal.
• Face: 14 bones (maxillae, zygomas, mandible, nasal bones, frontal).

Spine

• 33 vertebrae divided into five sections: cervical, thoracic, lumbar, sacral, coccyx(geal).
• Mnemonics: "Eat breakfast at 7 (cervical), lunch at 12 (thoracic), dinner at 5 (lumbar), snacks at 9 (sacral & coccyx)".
• Vertebrae consists of:
  • Vertebral body (round, solid bone).
  • Bony arch.
  • Large hole for the spinal cord.
  • Connected by ligaments and cushion discs (intervertebral discs).

Head Injuries

• Traumatic insult to the head, potentially injuring soft tissue, bony structures, or the brain.
• Accounts for over half of all traumatic deaths.
• Fatal injuries almost always include brain damage.
• Avoid tunnel vision; assess the whole patient.

Types of Head Injuries

• Closed Injuries: No penetration into the skull.
• Open Injuries: Penetration exposing the brain (high risk of infection).
  • Falls and MVCs are common MOIs.

Scalp Lacerations

• Can be minor or serious, resulting in significant blood loss (vascularized).
• Patients on blood thinners and children are at higher risk for hemorrhage.

Skull Fractures

• Significant force causes fractures (open or closed).

Signs of Skull Fracture

• Raccoon eyes (periorbital ecchymosis).
• Battle signs (periauricular ecchymosis).
• CSF drainage.

Types of Skull Fractures

• Linear Skull Fractures: Most common; crack in the skull, may not have mental deficits.
• Depressed Skull Fractures: Significant mechanism, blunt object; frontal and parietal bones are most susceptible; bony fragments can cause more damage.
• Basilar Skull Fractures: Base of the skull fractures from high-energy trauma (MVCs, falls); CSF drainage from ears, raccoon eyes, battle signs.
  • Contraindicated: Nasal airways.
• Open Skull Fractures: Sign of significant trauma (high mortality, secondary infection).

Traumatic Brain Injuries (TBIs)

• Traumatic insult to the brain causing physical, intellectual, emotional, social, and vocational changes.

Categories

• Primary brain injury: Initial impact.
• Secondary brain injury: Everything that comes afterward (hypoxia, hypotension, cerebral edema, increased intracranial pressure, cerebral ischemia, infection).
  • Hypoxia and hypotension are the most common.

Coup-Countercoup Injury

• Coup: Initial impact.
• Countercoup: Stretching of the back of the brain.
• Cerebral edema may develop hours after the initial injury.
• Patients with significant head injuries are at risk of seizing (call ALS early).

Increased Intracranial Pressure (ICP)

• Bleeding or swelling in the brain increases pressure.

Signs of ICP

• Abnormal respiratory patterns (ataxic or Cheyenne-Stokes respirations).
• Decreased pulse rate, headache, nausea, vomiting, diminished mental status.
• Sluggish or nonreactive pupils.
• Decerebrate (outward) posturing (worse than decorticate).
• Weakened or widening blood pressures.

Cushing's Triad (Cushing's Reflex)

• Indicates increased ICP.
• Increased systolic blood pressure, bradycardia, irregular respirations.

Types of Bleeding Inside the Skull

• Epidural Hematoma:
  • Accumulation of blood between the skull and dura mater.
  • Almost always from a direct blow to the head and linear fracture.
  • Arterial bleeding (rapidly progressing symptoms).
  • Lucid interval (unconscious, wakes up, then deteriorates).
  • Pupil on the side of hematoma is affected.
  • Life-threatening (requires surgical evacuation).
• Subdural Hematoma:
  • Accumulation of blood beneath the dura mater.
  • Falls and strong deceleration forces.
  • Venous bleeding (gradual signs).
  • Fluctuating level of consciousness, slurred speech (similar to strokes).
  • Can be fatal.
• Intracerebral Hematoma:
  • Bleeding within the brain tissue (bruise).
  • Penetrating injury or rapid deceleration forces.
  • Progression of ICP depends on other injuries and severity.
  • High mortality rate even with surgical evacuation.
• Subarachnoid Hemorrhage:
  • Bleeding into the subarachnoid space (CSF).
  • Trauma or ruptured aneurysm.
  • Bloody CSF, meningeal irritation, neck rigidity, headache.
  • Thunderclap headaches (sudden, severe).
  • Often fatal or severe neurological impairment.

Concussions vs. Contusions

• Concussions:
  • Blow to the head or face.
  • Temporary loss or alterations of brain function without demonstrable brain damage.
  • 90% do not experience loss of consciousness.
  • Associated with amnesia (retrograde or anterograde).
  • Symptoms: Dizziness, weakness, visual changes, mood changes, nausea, vomiting, tinnitus, slurred speech, inability to focus.
• Cerebral Contusion:
  • Bruising of the brain tissue (more severe than concussion).
  • Long-lasting or permanent damage.
  • General signs and symptoms of brain injury.
    • Skull depression, diminishmentations, irregular breathing, widening pulse flush pressures, bradycardia, bowel signs, raccoon eyes, CSF leakage, unequal pupils, loss of sensation or motor function, unconsciousness, amnesia (anterior grade or retrograde), seizures, numbness, tingling in the extremities, dizziness, visual deficits, abnormal behavior behavior, nausea and vomiting, or decorticate or deservative posturing.

Medical Conditions

• Brain injuries can arise from medical conditions (strokes, blood clots).
• Signs and symptoms are often the same as traumatic injuries.

Spinal Injuries

• Cervical, thoracic, and lumbar spine can be injured in various ways.

Mechanisms of Injury (MOI)

• Compression fractures (falls landing on the butt, blows to the head).
• Hyperflexion (MVCs).
• Rotation flexion injuries.
• Any unnatural movement can cause fractures or neurological deficits.
• Alteration of spinal bones may see step-off.

Significant MOIs

• MVCs (ATVs, motorcycles, snowmobiles).
• Pedestrian accidents.
• Blunt trauma.
• Penetrating trauma.
• Rapid deceleration.
• Hangings.
• Axial loading injuries.
• Diving accidents.
• Fall from height: >20 feet (adults), >10 feet (pediatrics).

Assessment and Management

• Early spinal immobilization.
• Questions: What happened? Where does it hurt? Does your neck or back hurt? Can you move your hands and feet? Did you hit your head?
• Medical causes (hypoglycemia) can mimic head injuries.
• Target O2 saturation 94% (do not want it to fall below 93%).
• Capnography 35-45 (30-35 ideal with head injuries)
• Decreased or altered mental status is a red flag.
• HALO test.
• Reassessment: Critical (5 minutes), noncritical (15 minutes).
• Time on scene: 10 minutes.

Backboards

• Negative effects: Pressure ulcers, nerve damage from straps.
• Elderly patients may have spinal deformities (kyphosis).
• Transport conscious patients in a position of comfort.
• Elevate head at least 30 degrees if ICP is suspected.
• Maintain in-line stabilization.
• C-collar sizing (fingers).
• Principles: Airway, breathing, circulation (ABCs); control bleeding; maintain level of consciousness.
• Suction prepared.
• Bag valve make ventilations if necessary.
• Control exsanguinating before hypoxia.
• Put the pressure on top.
• Do all your treatments for shock, flanky diesel, medic oxygen.
• Cushing's triad.
• Do not hyperventilate.

Special Circumstances

• Never force the head back in line if there's resistance, muscle spasms, pain, numbness, tingling, weakness or compromised airway.
• Vacuum Mattress- A vacuum mattress is basically just a moldable backboard. There's air in it. It seals around the patient and immobilizes them that way.
• KET Board Usage when you have to mobilize.
• Do standing patient takedowns.

Helmet Removal

• Two-person job.
• Leave on if no airway compromise, doesn't interfere with assessment, not bulky.
• Remove if full-face, difficulty assessing/managing airway, prevents immobilization, allows excessive head movement, patient in cardiac arrest.
• Unbuckle chin strap, remove face piece, pop out jaw pads.
• Partner 1 holds c-spine.
• Partner 2 slowly removes helmet.
• Insert padding behind the neck.