How to Evaluate Head Injury Severity

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The Definitive Guide to Evaluating Head Injury Severity

Head injuries are a leading cause of disability and death worldwide. Prompt and accurate assessment of their severity is paramount for effective treatment, predicting outcomes, and preventing secondary brain damage. This guide delves into the practical aspects of evaluating head injury severity, offering a clear, actionable framework for healthcare professionals and first responders. We’ll focus on the “how-to,” providing concrete examples and eliminating theoretical fluff to equip you with the tools for immediate application.

Initial Scene Assessment: Safety First, Then Patient Stability

Before even approaching the patient, a rapid scene assessment is critical. Your safety, and that of your team, takes precedence.

1. Scene Safety Checklist:

  • Environmental Hazards: Is there ongoing traffic, unstable structures, fire, chemical spills, or aggressive individuals?

  • Personal Protective Equipment (PPE): Don appropriate gloves, eye protection, and potentially a gown or mask, especially if body fluids are present.

  • Bystander Management: Secure the area and manage any bystanders to ensure their safety and prevent interference.

Example: You arrive at a motor vehicle accident. Before approaching the crumpled car, you note a strong smell of gasoline. Immediately, you establish a safe perimeter, alert the fire department, and instruct bystanders to move back. Only once the fire department has confirmed the scene is safe do you approach the vehicle.

2. Rapid Patient Assessment: Airway, Breathing, Circulation (ABC) and C-Spine Immobilization: Once the scene is safe, your immediate focus shifts to the patient’s life-threatening conditions. The ABCs are your priority, alongside maintaining cervical spine (C-spine) immobilization to prevent further neurological damage.

  • Airway (A):
    • Assessment: Is the airway patent? Look for foreign objects (vomit, blood, broken teeth), listen for noisy breathing (stridor, gurgling), and feel for air movement.

    • Action: If obstructed, perform a jaw-thrust maneuver (never a head-tilt chin-lift in suspected head trauma due to C-spine concerns) to open the airway. If necessary, use suction to clear secretions or a nasopharyngeal/oropharyngeal airway adjunct.

    • Example: You find a patient unconscious with gurgling respirations. You immediately perform a jaw-thrust. You then observe vomit in the mouth. Using a suction device, you clear the airway, and the gurgling subsides.

  • Breathing (B):

    • Assessment: Is the patient breathing? What is the rate, rhythm, and depth? Look for accessory muscle use, cyanosis, or paradoxical chest wall movement.

    • Action: If breathing is absent or inadequate, initiate ventilations with a bag-valve-mask (BVM) connected to high-flow oxygen.

    • Example: The patient is breathing shallowly at a rate of 8 breaths per minute. You immediately apply a non-rebreather mask with 15 L/min oxygen and prepare for assisted ventilations if their respiratory effort deteriorates.

  • Circulation (C):

    • Assessment: Check for a radial pulse (strong and regular?), skin color, temperature, and capillary refill time. Look for signs of significant external bleeding.

    • Action: Control any significant external bleeding with direct pressure. If signs of shock are present (tachycardia, pallor, hypotension), anticipate the need for fluid resuscitation upon arrival at a medical facility.

    • Example: You note a rapid, thready pulse and pale, cool, clammy skin. You immediately apply direct pressure to a laceration on the patient’s arm that is actively bleeding, while simultaneously noting the signs of hypovolemic shock.

  • C-Spine Immobilization:

    • Action: Maintain manual in-line stabilization of the head and neck until a rigid cervical collar can be applied and the patient is secured to a backboard or scoop stretcher. Assume C-spine injury in any significant head trauma until definitively ruled out.

    • Example: Your partner maintains manual in-line stabilization of the patient’s head and neck while you carefully apply a rigid cervical collar, ensuring it’s snug but not constricting.

Neurological Assessment: The Core of Severity Evaluation

Once immediate life threats are managed, a detailed neurological assessment is paramount. This forms the cornerstone of head injury severity evaluation.

1. Level of Consciousness (LOC): The AVPU Scale and Glasgow Coma Scale (GCS)

The LOC is the most critical indicator of brain function after a head injury.

  • AVPU Scale (Alert, Verbal, Pain, Unresponsive): This is a rapid, initial assessment tool for LOC, particularly useful in pre-hospital settings.
    • A – Alert: Patient is awake, spontaneously opens eyes, and aware of surroundings.

    • V – Verbal: Patient responds to verbal stimuli (e.g., opens eyes, makes sounds, moves extremities when spoken to).

    • P – Pain: Patient responds only to painful stimuli (e.g., sternal rub, nail bed pressure).

    • U – Unresponsive: Patient shows no response to any stimuli.

    • Example: You call out the patient’s name, and they groan and open their eyes briefly. This would be a “V” (Verbal) on the AVPU scale.

  • Glasgow Coma Scale (GCS): The GCS is the gold standard for assessing LOC in head injury. It provides a more precise and objective measure by evaluating three components: Eye Opening, Verbal Response, and Motor Response. Each component is scored, and the total score ranges from 3 (deep coma) to 15 (fully awake).

    • Eye Opening (E) – Maximum 4 points:
      • 4 – Spontaneously: Eyes open without stimulation.

      • 3 – To speech: Eyes open when spoken to.

      • 2 – To pain: Eyes open only in response to painful stimuli.

      • 1 – None: No eye opening.

      • Example: You arrive to find the patient’s eyes closed. You say, “Can you open your eyes for me?” and they slowly open them. This is an E3.

    • Verbal Response (V) – Maximum 5 points:

      • 5 – Orientated: Answers questions correctly (person, place, time).

      • 4 – Confused: Answers questions, but disoriented or confused.

      • 3 – Inappropriate words: Utters random words or exclamations.

      • 2 – Incomprehensible sounds: Moans or groans, no recognizable words.

      • 1 – None: No verbal response.

      • Example: You ask, “What day is it?” and the patient replies, “It’s Tuesday, I think…” when it’s actually Wednesday. This is a V4.

    • Motor Response (M) – Maximum 6 points:

      • 6 – Obeys commands: Follows instructions (e.g., “Squeeze my hand”).

      • 5 – Localizes to pain: Moves to remove the painful stimulus.

      • 4 – Withdraws to pain: Flexes arm away from painful stimulus.

      • 3 – Abnormal flexion (decorticate): Arms flexed, wrists and fingers flexed, legs extended, feet plantar flexed (sign of severe brain injury).

      • 2 – Abnormal extension (decerebrate): Arms extended, adducted, pronated, wrists and fingers flexed, legs extended, feet plantar flexed (even more severe brain injury).

      • 1 – None: No motor response.

      • Example: You apply a sternal rub, and the patient tries to push your hand away. This is an M5.

    • GCS Score Interpretation:

      • Mild Head Injury: GCS 13-15

      • Moderate Head Injury: GCS 9-12

      • Severe Head Injury: GCS 3-8

    • Important Note: Document the individual components (E, V, M) as well as the total GCS score. This provides more detailed information for tracking changes. Repeat GCS assessments frequently, especially if the patient’s condition changes.

2. Pupil Assessment: Size, Symmetry, Reactivity to Light (PERRL)

Pupil assessment provides crucial insights into brain stem function and potential intracranial pressure (ICP) changes.

  • Procedure: Use a penlight to assess each pupil individually.
    • Size: Note the size of each pupil (e.g., 3mm, 5mm). Are they equal?

    • Symmetry: Are both pupils the same size? Asymmetry (anisocoria) can indicate a neurological emergency.

    • Reactivity to Light (Direct and Consensual): Shine the light into one pupil and observe its constriction (direct response). Then, observe the constriction of the other pupil (consensual response). Repeat for the other eye. Document if they are brisk, sluggish, or non-reactive.

  • Significance:

    • Dilated and Fixed Pupil (unilateral): Often indicates ipsilateral (same side) oculomotor nerve (CN III) compression, frequently due to uncal herniation from an expanding mass lesion (e.g., epidural or subdural hematoma). This is a neurological emergency.

    • Bilaterally Dilated and Fixed Pupils: Can indicate severe anoxia, brain death, or certain drug effects.

    • Pinpoint Pupils: Can be caused by opiate overdose or pontine lesions.

  • Example: Your patient has a GCS of 7. Upon pupil assessment, you note the right pupil is 7mm and sluggishly reactive to light, while the left pupil is 3mm and briskly reactive. This finding is highly concerning for an expanding mass lesion on the right side of the brain.

3. Motor and Sensory Examination: Strength, Sensation, Reflexes

While a comprehensive neurological exam may not be feasible in an emergency, specific elements are vital.

  • Motor Strength: Assess strength in all four extremities.
    • Procedure: Ask the patient to push/pull against resistance. Use a simple scale (e.g., 0-5, where 0=no movement, 5=normal strength). Compare left to right.

    • Significance: Unilateral weakness (hemiparesis) can indicate a lesion in the contralateral motor cortex or descending tracts.

    • Example: You ask the patient to squeeze your fingers. The right hand grip is strong, but the left hand grip is significantly weaker. This indicates left-sided weakness.

  • Sensory Examination:

    • Procedure: Briefly check light touch or pain sensation in all four extremities. Ask if the patient can feel your touch equally on both sides.

    • Significance: Sensory deficits can help localize spinal cord or brain lesions.

    • Example: You lightly touch the patient’s left leg and then their right. They state they can feel it on the right but not on the left, suggesting a sensory deficit.

  • Deep Tendon Reflexes (DTRs):

    • Procedure: If time and situation allow, check knee and ankle reflexes.

    • Significance: Absent or exaggerated reflexes can point to specific neurological pathways affected.

4. Cranial Nerves (Brief Assessment):

While a full cranial nerve exam is extensive, a few key assessments can be performed.

  • Facial Symmetry (CN VII): Ask the patient to smile, frown, or puff out their cheeks. Look for drooping.

  • Tongue Deviation (CN XII): Ask the patient to stick out their tongue. Does it deviate to one side?

  • Example: The patient attempts to smile, but the left side of their face remains flat, indicating potential facial nerve weakness.

Signs of Increased Intracranial Pressure (ICP)

Rising ICP is a life-threatening complication of head injury. Recognize its signs early.

1. Cushing’s Triad: This is a late, ominous sign of significantly elevated ICP.

  • Bradycardia: Slow heart rate.

  • Systolic Hypertension (widening pulse pressure): An increasing difference between systolic and diastolic blood pressure.

  • Irregular Respirations: Cheyne-Stokes breathing, central neurogenic hyperventilation, or ataxic breathing.

  • Example: Your patient’s vital signs are: HR 45 bpm, BP 180/60 mmHg, and irregular, gasping respirations. These are classic signs of Cushing’s Triad, indicating severe ICP elevation.

2. Other Signs of Increased ICP:

  • Headache: Persistent and worsening.

  • Nausea and Vomiting: Often projectile, not necessarily associated with eating.

  • Papilledema: Swelling of the optic disc (seen on funduscopic exam, usually a later sign).

  • Altered Mental Status: Restlessness, irritability, confusion, decreasing GCS.

  • Posturing: Decorticate or decerebrate posturing (as described in GCS motor component).

Detailed Head and Neck Examination

Beyond the neurological assessment, a thorough physical examination of the head and neck is crucial for identifying direct injury.

1. Scalp and Skull Palpation:

  • Procedure: Gently but thoroughly palpate the entire scalp and skull for:
    • Lacerations: Note size, depth, and bleeding.

    • Contusions/Hematomas: Feel for soft, boggy areas (e.g., “goose egg”).

    • Depressions/Crepitus: Feel for areas where the skull is indented or for a crackling sensation, which indicates a skull fracture.

    • Battle’s Sign: Bruising behind the ear (mastoid process), often appearing hours to days after a basilar skull fracture.

    • Raccoon Eyes (Periorbital Ecchymosis): Bruising around both eyes, also a sign of a basilar skull fracture.

    • Example: You feel a soft, boggy area over the left temporal region of the skull, which is consistent with a subgaleal hematoma. Further palpation reveals a subtle depression, raising suspicion for a depressed skull fracture.

2. Face Examination:

  • Procedure: Inspect and palpate the facial bones.
    • Facial Asymmetry: Look for drooping, swelling, or deviation.

    • Crepitus: Feel for crackling, indicating potential facial fractures.

    • Eye Movement: Check extraocular movements (though this can be difficult in a less cooperative patient).

    • Example: You note swelling and tenderness over the patient’s left cheekbone, and they report pain with jaw movement, suggesting a potential zygomatic fracture.

3. Ear and Nose Examination:

  • Procedure: Look for drainage from the ears or nose.
    • Otorrhea/Rhinorrhea: Clear fluid (cerebrospinal fluid – CSF) leaking from the ear or nose. Test with a Dextrostix for glucose (CSF contains glucose).

    • Blood: Presence of blood, especially with CSF, can indicate a basilar skull fracture.

    • Hemotympanum: Blood behind the eardrum (seen with an otoscope), another sign of a basilar skull fracture.

    • Example: You observe a clear, watery discharge from the patient’s right nostril. You perform a Dextrostix test, which is positive for glucose, strongly indicating CSF rhinorrhea from a basilar skull fracture.

4. Neck Examination:

  • Procedure: While maintaining C-spine precautions, gently inspect and palpate the neck.
    • Deformity/Tenderness: Look for obvious deformity or tenderness along the cervical spine.

    • Tracheal Deviation: A late and serious sign of tension pneumothorax or other mediastinal shifts.

    • Jugular Venous Distention (JVD): Can indicate fluid overload, cardiac tamponade, or tension pneumothorax.

    • Example: With your partner maintaining manual in-line stabilization, you gently palpate the patient’s neck. You note significant tenderness over the C5-C6 spinous processes, raising concern for a cervical spine fracture.

Mechanism of Injury (MOI) and Associated Injuries

Understanding how the injury occurred is vital, as it provides clues to potential injury severity and patterns.

1. High-Energy vs. Low-Energy Mechanisms:

  • High-Energy: Falls from height, high-speed motor vehicle accidents, pedestrian struck by vehicle, assault with significant force, penetrating injuries (gunshot, stab wounds). These mechanisms are associated with a higher likelihood of severe head and associated injuries.

  • Low-Energy: Simple falls from standing, minor blunt trauma. While these can still cause significant injury, the likelihood of severe injury is lower.

  • Example: A patient struck by a car traveling at 60 km/h is a high-energy mechanism, immediately raising concerns for significant head trauma, internal injuries, and fractures. In contrast, an elderly person who tripped and fell while walking would be a lower-energy mechanism, though their increased fragility still warrants careful assessment.

2. Type of Force:

  • Blunt Trauma: Most common, caused by impact with a blunt object (e.g., fist, dashboard, ground). Can cause contusions, lacerations, fractures, and diffuse axonal injury.

  • Penetrating Trauma: Caused by objects piercing the skull (e.g., bullet, knife). High risk of infection, direct brain damage, and hemorrhage.

  • Deceleration/Acceleration Injuries (Whiplash): Sudden stopping or starting motions that cause the brain to move within the skull, leading to diffuse axonal injury, contusions, and shearing forces. Common in motor vehicle accidents.

  • Crush Injuries: Direct compression of the head.

3. Associated Injuries:

  • Polytrauma: Head injuries rarely occur in isolation in major trauma. Always assume other injuries until ruled out.
    • Spinal Cord Injuries: Up to 10% of patients with head injury also have a spinal cord injury. ALWAYS maintain C-spine precautions.

    • Chest Trauma: Pneumothorax, hemothorax, rib fractures.

    • Abdominal Trauma: Solid organ injury, hollow viscus perforation.

    • Extremity Fractures: Long bone fractures, pelvic fractures.

    • Example: After stabilizing the head injury patient from the car accident, you perform a rapid body scan and discover significant bruising over the left chest with paradoxical movement, indicating potential rib fractures and a flail chest. This underscores the importance of a comprehensive assessment.

Red Flags for Immediate Medical Attention

Certain signs and symptoms demand immediate, often emergent, medical intervention. These are “red flags” that signify potential for severe, rapidly deteriorating conditions.

  • Decreasing GCS Score: Any drop of 2 points or more is highly concerning.

  • Unequal Pupils or New Pupil Abnormality: Suggests brain herniation.

  • Focal Neurological Deficits: New or worsening weakness, numbness, speech changes.

  • Seizures (post-traumatic): Can indicate severe brain irritation or injury.

  • Cushing’s Triad: Sign of impending brain herniation.

  • CSF Leakage from Ears or Nose: Indicative of a basilar skull fracture.

  • Persistent Vomiting: Especially projectile, suggests increased ICP.

  • Severe, Worsening Headache: Particularly if it’s new or different for the patient.

  • Amnesia (post-traumatic or retrograde): While common, significant or worsening amnesia is a red flag.

  • Loss of Consciousness > 30 seconds: Indicates a more significant impact.

  • Any suspicion of Skull Fracture: Especially depressed or open fractures.

  • Known Coagulopathy or Anticoagulant Use: Increases risk of intracranial hemorrhage.

  • Drug or Alcohol Intoxication Masking Symptoms: Makes assessment difficult and increases risk.

  • Age Extremes: Very young children and elderly individuals are more vulnerable to severe injury from seemingly minor trauma.

  • Example: A patient with an initial GCS of 14 suddenly drops to 11, and you notice their right pupil has become dilated and fixed. This constellation of findings requires immediate, aggressive intervention and rapid transport to a trauma center.

Documentation and Reassessment

Accurate and timely documentation is not just good practice; it’s essential for continuity of care and monitoring changes.

1. What to Document:

  • Time of Injury: As precise as possible.

  • Mechanism of Injury: Detailed description.

  • Initial GCS Score (E, V, M components) and Subsequent Scores: Note time of each assessment.

  • Pupil Assessment: Size, symmetry, reactivity (time of assessment).

  • Vital Signs: BP, HR, RR, SpO2, temperature (time of each set).

  • Detailed Head and Neck Exam Findings: Lacerations, contusions, depressions, signs of CSF leak, etc.

  • Neurological Findings: Motor strength, sensation, any focal deficits.

  • Associated Injuries: Any other identified trauma.

  • Interventions Performed: Airway management, bleeding control, C-spine immobilization, oxygen administration.

  • Patient’s Response to Interventions.

  • Any Changes in Condition: Deterioration or improvement.

2. Frequency of Reassessment:

  • Severe Head Injury (GCS 3-8): Continuous monitoring, reassess GCS and pupils every 5-15 minutes.

  • Moderate Head Injury (GCS 9-12): Reassess GCS and pupils every 15-30 minutes.

  • Mild Head Injury (GCS 13-15): Reassess GCS and pupils every 30-60 minutes, or more frequently if any change.

  • Any Deterioration: Immediately reassess and notify medical command/receiving facility.

Example: You document: “14:30 – MVC, pedestrian vs. car. Initial GCS E4V5M6=15. Pupils 3mm reactive bilaterally. No apparent head trauma. 14:45 – Patient now irritable, GCS E4V4M6=14. Pupils remain 3mm reactive. Reassessing every 15 mins. Notified trauma team of change.” This clear, timed documentation allows the receiving team to quickly grasp the patient’s trajectory.

Pediatric and Geriatric Considerations

Head injuries in the very young and very old warrant special attention due to physiological differences and increased vulnerability.

1. Pediatric Head Injury:

  • Scalp Lacerations: Can cause significant blood loss due to highly vascular scalp.

  • Open Fontanelles: Can mask signs of increased ICP in infants by allowing for some brain expansion. However, a bulging fontanelle is a significant sign of ICP.

  • Non-Accidental Trauma (NAT)/Child Abuse: Always consider in unexplained injuries or inconsistent stories.

  • Signs of ICP in Infants/Young Children: Irritability, high-pitched cry, poor feeding, lethargy, bulging fontanelle, sunsetting eyes (downward deviation of eyes), vomiting.

  • Difficulty with GCS: Verbal and motor components of GCS need adaptation for age. Use the Pediatric GCS.

  • Example: An infant presents with a significant scalp hematoma and is unusually lethargic and irritable. You notice a bulging anterior fontanelle. These signs, despite a potentially normal GCS equivalent, are highly concerning for increased ICP in an infant.

2. Geriatric Head Injury:

  • Brain Atrophy: The aging brain shrinks, creating more space within the skull. This can allow for larger intracranial hematomas to accumulate before symptoms appear, delaying diagnosis.

  • Anticoagulant Use: Elderly patients are often on anticoagulants (e.g., warfarin, novel oral anticoagulants), increasing their risk of severe intracranial hemorrhage from minor trauma.

  • Comorbidities: Pre-existing conditions (e.g., heart disease, diabetes, dementia) can complicate assessment and management.

  • Fragile Blood Vessels: More prone to tearing with minor trauma.

  • Example: An 85-year-old patient on warfarin fell from a standing height. Initially, they are alert and oriented. However, over several hours, they become progressively confused and develop unilateral weakness. This delayed presentation, common in the elderly, highlights the need for a low threshold for imaging in this population.

Conclusion

Evaluating head injury severity is a dynamic, multi-faceted process demanding systematic assessment, keen observation, and constant re-evaluation. By meticulously applying the principles of ABCs, detailed neurological examination (especially GCS and pupils), thorough physical assessment, and understanding the mechanism of injury, healthcare providers can accurately gauge severity, identify red flags, and initiate life-saving interventions. This practical guide equips you with the actionable knowledge to make informed decisions in the critical moments following a head injury, ultimately improving patient outcomes.