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Intracranial Bleeds

Overview of Bleeds

  • There are two main types of intracranial bleeds discussed: subdural and epidural.

Subdural Hematomas

  • Definition: Slow venous bleeding that occurs in the brain, often between the brain surface and outer covering (dura mater).
  • Symptoms:
    • Patients may initially exhibit normal mental acuity.
    • Changes in mental state can be lucidity followed by drowsiness, then coma, often without noticeable progression.
    • Often, patients declare they feel fine, leading to a false sense of security.
  • Mechanism of Death:
    • Typically occurs when the rate of blood accumulation exceeds reabsorption rate overnight, leading to pressure in the brain.
  • Prone Populations:
    • Elderly patients are particularly prone due to:
    • Brain shrinkage with age.
    • Decreased production of cerebrospinal fluid (CSF) leading to a tighter space for the subarachnoid veins, increasing likelihood of tearing during falls.

Epidural Hematomas

  • Definition: Arterial bleeding that is more aggressive than subdural bleeding due to rapid accumulation of blood.
  • Symptoms:
    • Deterioration of patient conditions can occur swiftly, often within minutes.
    • Patients may lose consciousness relatively quickly after injury.
  • Mechanism of Bleed:
    • The bleeding occurs rapidly (minutes), usually from a head trauma that ruptures an artery, thus producing dramatic symptoms.

Key Differences Between Subdural and Epidural Bleeds

  • Speed of Deterioration:
    • Epidural: Minutes
    • Subdural: 12 to 24 hours
  • Nature of Blood Accumulation:
    • Epidural: Rapid and aggressive (arterial bleeding)
    • Subdural: Slow and insidious (venous bleeding)

Treatment Approaches

  • Epidural Hematoma Treatment:
    • Involves a surgical procedure using a drill to access the bleed.
    • Care must be taken with the drilling technique to avoid further brain damage.
    • Insertion of a one-way valve to control intracranial pressure, followed by transfer to a neurosurgeon for further management.
    • Emergency Response Context:
    • Patients should be transported to a level one trauma center for the best care from neurosurgeons.

Vital Signs and Symptoms Assessment

  • Differentiating Signs:
    • Bounding pulse: Indicative of increased intracranial pressure (not hypotension like in shock).
    • Normal pulse: steady beats (boom, boom).
    • Bounding pulse: pronounced, rapid beats indicating potential signals of intracranial issues.
    • Thready pulse: Often associated with shock states, indicative of reduced blood pressure.

General Clinical Principles

  • Initial Patient Assessment:
    • Always assess the mechanism of injury and patient age, particularly with head injuries.
    • Be cautious with patients showing lucidity post-injury, as they may decline further medical evaluation.
  • Management Focus:
    • Ensure airway management and provide respiratory support if necessary, as patients may show seizure activity due to increased pressure.
    • Rapid transport is crucial as timing can determine survival rates.

Special Cases: Subarachnoid Hemorrhage

  • Common Symptoms:
    • Severe headache (thunderclap headache) described as if a bomb exploded in the skull.
    • Changes in pupil size and response can indicate serious neurological issues.
    • Midpoint and dilated pupils can suggest potential bleeding locations within the brain.

Key Takeaways for Examination Preparation

  • Difference in Bleeds: Be prepared to identify and differentiate the types of bleeds based on symptoms and mechanisms.
  • Importance of Rapid Response: Understand the critical first-response measures and the importance of transporting patients to a higher-level trauma center.