How to Thoroughly Assess Head Injuries in Adults: A Detailed Guide for Medical Students

Assessing head injuries in adults is a critical skill for medical students and healthcare professionals. Head injuries can range from minor concussions to life-threatening traumatic brain injuries (TBIs), and a prompt, accurate assessment is vital to prevent complications and ensure the best possible outcomes. This guide will cover the essential steps in evaluating head injuries, including initial assessment, clinical examination, imaging, and management, with a focus on practical tips and considerations for real-world scenarios.


1. Understanding the Basics: Types of Head Injuries

Head injuries can be classified into two main categories:

1. Closed Head Injuries: These occur when the brain is injured without any penetration of the skull. Common causes include falls, motor vehicle accidents, and sports injuries. Examples include:
   • Concussion: A mild traumatic brain injury with transient loss of brain function.
   • Contusion: Bruising of the brain tissue, often due to direct impact.
   • Diffuse Axonal Injury (DAI): Widespread damage to the brain's white matter tracts, typically from rotational forces.
   • Intracranial Hemorrhage: Bleeding within the skull, including subdural hematoma, epidural hematoma, and intracerebral hemorrhage.
2. Penetrating Head Injuries: These involve an object breaking through the skull and entering the brain tissue, often resulting in severe damage. Examples include gunshot wounds and stab injuries.

2. Initial Assessment: The ABCDE Approach

The initial assessment of a head injury should follow the ABCDE approach, a systematic method used in trauma care:

• A - Airway with Cervical Spine Control: Ensure the airway is patent while maintaining cervical spine precautions. Look for signs of airway obstruction, such as facial trauma, blood, or vomitus. If the patient is unresponsive, consider intubation.
• B - Breathing: Assess the patient's breathing and ventilation. Look for signs of respiratory distress or failure, which could indicate brainstem involvement. Use pulse oximetry to monitor oxygen saturation.
• C - Circulation: Check the patient's pulse, blood pressure, and capillary refill. Hypotension is uncommon in isolated head injuries and may indicate other injuries. Establish IV access and initiate fluid resuscitation if necessary.
• D - Disability (Neurological Assessment): Perform a quick neurological evaluation using the Glasgow Coma Scale (GCS), which assesses eye opening, verbal response, and motor response. This is crucial for determining the severity of the head injury. Also, check for pupil size and reactivity, limb movement, and signs of lateralizing neurological deficits.
• E - Exposure/Environment: Expose the patient to assess for other injuries, while preventing hypothermia. Look for signs of trauma, such as lacerations, skull fractures, or Battle's sign (bruising behind the ears, indicative of a basilar skull fracture).

3. Detailed Neurological Examination

A thorough neurological examination is essential in assessing head injuries. The examination should include:

• Level of Consciousness (LOC): Assess the patient's alertness and ability to follow commands. Changes in LOC are often the first sign of worsening brain injury.
• Pupil Examination: Check for size, symmetry, and reaction to light. Unequal pupils (anisocoria) may indicate a brain herniation.
• Cranial Nerve Examination: Test all cranial nerves, particularly focusing on those that can be affected by head injuries:
  • CN II (Optic Nerve): Visual acuity and visual fields.
  • CN III (Oculomotor Nerve): Pupil size and reaction, eye movements.
  • CN VII (Facial Nerve): Facial symmetry and movement.
  • CN VIII (Vestibulocochlear Nerve): Hearing and balance.
• Motor and Sensory Examination: Assess strength in all limbs and check for sensory deficits. This helps identify focal neurological injuries.
• Coordination and Gait: If the patient is able, test coordination with finger-to-nose and heel-to-shin tests. Observe the patient's gait.
• Reflexes: Check deep tendon reflexes, plantar responses (Babinski sign), and assess for any abnormal reflexes that may indicate neurological damage.

4. Red Flags: When to Suspect Severe Brain Injury

Certain clinical signs should raise concern for severe brain injury and prompt urgent intervention:

• GCS < 8: A GCS score of less than 8 indicates a severe brain injury and often necessitates intubation and neurosurgical evaluation.
• Pupil Asymmetry or Fixed Dilated Pupils: These may suggest increased intracranial pressure (ICP) or brain herniation.
• Cushing’s Triad: This includes hypertension, bradycardia, and irregular respiration, indicative of raised ICP and impending herniation.
• Seizures: New-onset seizures following a head injury are concerning for intracranial bleeding or contusion.
• Posturing: Decerebrate (extensor) or decorticate (flexor) posturing suggests severe brainstem or cortical damage.

5. Imaging in Head Injury: When and What to Order

CT Scan is the imaging modality of choice for assessing head injuries, particularly in the acute setting. The decision to order a CT scan should be guided by clinical criteria:

• Indications for CT Scan in Head Injury:
  • GCS < 13 on initial assessment.
  • GCS < 15 two hours after injury.
  • Suspected skull fracture (e.g., palpable step-off, Battle’s sign).
  • Signs of basilar skull fracture (e.g., raccoon eyes, CSF rhinorrhea).
  • Post-traumatic seizure.
  • Focal neurological deficit.
  • More than one episode of vomiting.
  • Amnesia for events > 30 minutes before impact.
  • Dangerous mechanism of injury (e.g., ejection from vehicle, fall from height > 1 meter).

MRI may be used later in the management of head injuries, particularly for assessing diffuse axonal injury, brainstem injuries, or when there is a clinical suspicion of brain injury that is not visible on CT.


6. Management of Head Injury

The management of head injuries depends on the severity of the injury and the findings from the clinical assessment and imaging:

• Mild Head Injury (Concussion):
  • Observation and rest are key. Most patients recover fully within a few weeks.
  • Educate patients about post-concussion syndrome, which can include headaches, dizziness, and cognitive difficulties.
  • Gradual return to normal activities, including work or sports, should be advised.
• Moderate to Severe Head Injury:
  • Patients with a GCS < 13 should be admitted for observation and management.
  • ICP Monitoring: Indicated for patients with severe head injury (GCS ≤ 8) and abnormal CT findings. Management of elevated ICP may include head elevation, osmotic therapy (e.g., mannitol, hypertonic saline), and hyperventilation.
  • Surgery: Neurosurgical intervention may be required for mass lesions (e.g., hematomas) causing significant mass effect or midline shift.
  • Seizure Prophylaxis: Consider in patients with severe head injury to prevent early post-traumatic seizures.
• Post-Acute Management:
  • Rehabilitation is critical for patients with moderate to severe head injuries. This includes physical therapy, occupational therapy, speech therapy, and cognitive rehabilitation.
  • Monitor for long-term complications such as post-traumatic epilepsy, chronic headaches, and neuropsychiatric disorders.

7. Special Considerations

• Anticoagulation: Patients on anticoagulant therapy (e.g., warfarin, direct oral anticoagulants) are at higher risk for intracranial hemorrhage even with minor head injuries. Immediate CT scanning and reversal of anticoagulation may be necessary.
• Elderly Patients: Older adults are more susceptible to head injuries and have a higher risk of complications. They may present with atypical symptoms and have a delayed onset of intracranial bleeding.
• Alcohol and Substance Use: Intoxicated patients may have an altered mental status, making it challenging to assess the severity of a head injury. A high index of suspicion is required, and imaging should be considered.

8. Legal and Ethical Considerations

Healthcare professionals must be aware of the legal and ethical implications of managing head injuries:

• Documentation: Thorough documentation of the initial assessment, clinical findings, and management plan is crucial. This includes recording GCS scores, neurological findings, and any changes in the patient’s condition.
• Informed Consent: Patients (or their legal representatives) should be informed about the risks, benefits, and alternatives to any proposed interventions, especially in cases requiring surgery or ICU admission.
• Reporting: In cases of suspected non-accidental injury (e.g., domestic violence, assault), it is the healthcare professional’s duty to report the incident to the appropriate authorities while ensuring the patient’s safety.