Intro

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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Connolly ES, Rabinstein AA, Carhuapoma JR, et al. Guidelines for the management of aneurysmal subarachnoid hemorrhage: a guideline for healthcare professionals from the American Heart Association/american Stroke Association. Stroke. 2012;43(6):1711-1737.

Czuczman AD, Thomas LE, Boulanger AB, et al. Interpreting red blood cells in lumbar puncture: distinguishing true subarachnoid hemorrhage from traumatic tap. Acad Emerg Med. 2013;20(3):247-256.

Dugas C, Jamal Z, Bollu PC. Xanthochromia. [Updated 2020 Aug 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK526048/

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Meurer WJ, Walsh B, Vilke GM, Coyne CJ. Clinical guidelines for the emergency department evaluation of subarachnoid hemorrhage. J Emerg Med. 2016;50(4):696-701.

Perry JJ, Spacek A, Forbes M, et al. Is the combination of negative computed tomography result and negative lumbar puncture result sufficient to rule out subarachnoid hemorrhage? Ann Emerg Med. 2008;51(6):707-713

Perry JJ, Stiell IG, Sivilotti MLA, et al. High risk clinical characteristics for subarachnoid haemorrhage in patients with acute headache: prospective cohort study. BMJ. 2010;341:c5204.

Perry JJ, Stiell IG, Sivilotti MLA, et al. Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: prospective cohort study. BMJ. 2011;343(jul18 1):d4277-d4277.

Perry JJ, Stiell IG, Sivilotti ML, et al. Clinical decision rules to rule out subarachnoid hemorrhage for acute headache. JAMA. 2013;310(12):1248-55.

Perry JJ, Sivilotti MLA, Sutherland J, et al. Validation of the Ottawa Subarachnoid Hemorrhage Rule in patients with acute headache. CMAJ. 2017;189(45):E1379-E1385.

Vermeulen MJ, Schull MJ. Missed diagnosis of subarachnoid hemorrhage in the emergency department. Stroke. 2007;38(4):1216-21.