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Chief Complaint


Organ System


Fisher Grading Scale for Subarachnoid Hemorrhage (SAH)

Rates risk of vasospasm in aSAH based on amount and distribution of blood on CT.

This scale only applies to aneurysmal subarachnoid hemorrhage (aSAH). We recommend using the Modified Fisher Grading Scale based on more recent studies.

Clinician must be able to identify subarachnoid hemorrhage (SAH) and major neuroanatomical landmarks on head CT.


  • Immediate neurological and neurosurgical consultation should be obtained for patients with evidence of any SAH on imaging or lumbar puncture, even if the SAH is likely to be 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 a neurological or neurosurgical consultant first.
  • Similarly, the decision to start medications that have been shown to alter outcomes in aSAH (such as nimodipine and/or aminocaproic acid) should be deferred to the neurological or neurosurgical consultant.
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