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    Chief Complaint


    Organ System


    Patent Pending

    Hunt & Hess Classification of Subarachnoid Hemorrhage

    Classifies severity of subarachnoid hemorrhage to predict mortality.
    When to Use
    Why Use

    Patients with aSAH.

    • The Hunt-Hess classification system was originally intended to help determine the risk of surgical mortality in patients admitted with aSAH.
    • Higher grades, which are reflective of progressively higher hemorrhage severity and neurological dysfunction, are associated with higher overall mortality.
    • The scale was originally measured at admission and is typically used this way. Because it is purely clinical, the scale can change (for better or worse) during a patient’s hospital course.
    • Each grade corresponds to a specific set of clinical examination findings from 3 areas (level of arousal, reflexes, and meningeal irritation); a patient may present with a different combination of findings than that dictated by a given Hunt-Hess grade. Clinical judgment should be used to determine the final grade in these cases. (Rosen 2005)

    Points to keep in mind:

    • The scale does not apply to SAH due to trauma, arteriovenous malformations, cavernous angiomas, dural arteriovenous fistulae, cortical or sinus venous thromboses, mycotic aneurysms, or septic emboli with hemorrhagic transformation.
    • The scale is vulnerable to intra- and inter-observer variability due to the fact that it is solely based on the patient’s subjective reports and the physical examination.
    • The Hunt-Hess scale was not originally conceived to predict morbidity or degree of disability from SAH.

    This scale should NOT be used as the only clinical decision making tool in a patient with aSAH.

    This scale assumes you have a grasp of the neurological clinical examination, such as the assessment of level of consciousness, cranial nerves, and motor examination.

    • The mean case-fatality rate of aSAH is 39% (Nieuwkamp 2009) and the Hunt–Hess classification can help predict mortality in such patients.
    • The Hunt-Hess scale is widely known in the neurocritical care community.
    • The only thing needed for determining Hunt-Hess grade is the clinical examination; radiographic imaging is not necessary.
    Mild Headache, Alert and Oriented, Minimal (if any) Nuchal Rigidity
    Full Nuchal Rigidity, Moderate-Severe Headache, Alert and Oriented, No Neuro Deficit (Besides CN Palsy)
    Lethargy or Confusion, Mild Focal Neurological Deficits
    Stuporous, More Severe Focal Deficit
    Comatose, showing signs of severe neurological impairment (ex: posturing)


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    Next Steps
    Creator Insights


    • Immediate neurological and neurosurgical consultation should be obtained on patients with evidence of any SAH on imaging or lumbar puncture, irrespective of whether the SAH is likely to be aneurysmal or non-aneurysmal in nature.
    • Computed tomographic angiography (CTA) of the head is helpful to determine the presence of a lesion suitable for surgical or endovascular intervention.
    • The need for obtaining cerebrovascular imaging, such as CTA of the head or catheter angiography, should be discussed with neurological or neurosurgical consultant first.
    • Similarly, the decision to start medications that have been shown to alter outcomes in aSAH (such as nimodipine and aminocaproic acid) should be deferred to the neurological or neurosurgical consultant.
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    Dr. William E. Hunt
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