Episode 181.0: Subarachnoid Hemorrhage

We discuss EM presentation, diagnosis, and management of subarachnoid hemorrhage.

Mark Iscoe, MD
Brian Gilberti, MD
Bree Tse, MD

March 4th, 2021 Download One Comment Tags: , ,

Show Notes

Non-contrast head CT showing SAH (Case courtesy of Dr. David Cuete, Radiopaedia.org, rID: 22770)


Hunt-Hess grade and mortality (from Lantigua et al. 2015.)

Hunt-Hess grade Mortality (%)
1. Mild Headache 3.5
2. Severe headache or cranial nerve deficit 3.2
3. Confusion, lethargy, or lateralized weakness 9.4
4. Stupor 23.6
5. Coma 70.5


Ottawa Subarachnoid Hemorrhage Rule, and appropriate population for rule application (from Perry et al. 2017)

Apply to patients who are:

  • Alert
  • ≥ 15 years old
  • Have new, severe, atraumatic headache that reached maximum intensity within 1 hour of osnet

Do not apply to patients who have:

  • New neurologic deficits
  • Previous diagnosis of intracranial aneurysm, SAH, or brain tumor
  • History of similar headaches (≥ 3 episodes over ≥ 6 months)

SAH cannot be ruled out if the patient meets any of the following criteria:

  • Age ≥ 40
  • Symptom of neck pain or stiffness
  • Witnessed loss of consciousness
  • Onset during exertion
  • “Thunderclap headache” (defined as instantly peaking pain)
  • Limited neck flexion on examination (defined as inability to touch chin to chest or raise head 3 cm off the bed if supine)



Special Thanks To:

  • Dr. Mark Iscoe, MD (Ronald O. Perelman Department of Emergency Medicine at NYU Langone Health, NYC Health + Hospitals/ Bellevue)



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