Skip to main content

Table 3 Ottawa Subarachnoid Hemorrhage rule [11]

From: Subarachnoid hemorrhage in the emergency department

For alert patients > 15 years of age with new severe non-traumatic headache reaching maximum intensity within 1 h
Not for patients with new neurologic deficits, previous aneurysms, SAH, brain tumors, or history of similar headaches (≥ 3 episodes over ≥ 6 months)
Investigate further if ≥ 1 finding is present
1. Symptoms of neck pain or stiffness
2. Age ≥ 40 years old
3. Witnessed loss of consciousness
4. Onset during exertion
5. Thunderclap headache (peak intensity immediately)
6. Limited neck flexion on exam