Understanding Atraumatic Subarachnoid Hemorrhages

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.)

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)

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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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References:

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