Atraumatic subarachnoid haemorrhage: A prospective cases series

Abstract

Background: Subarachnoid haemorrhage (SAH) is an infrequent cause of headaches but has catastrophic consequences if missed. Objectives: 1) To describe the clinical findings of a prospective case-series of SAH; 2) To retrospectively apply and evaluate the Ottawa SAH rule. Method: This is a planned sub-study of a snapshot across 34 EDs in Queensland over 4weeks in September 2014. In that study, patients ≥18 years with a headache or suspicion of SAH were enrolled. The treating doctor collected details about the headache. A research officer abstracted data on investigations and diagnosis from statewide databases. Results: Twenty cases of SAH were diagnosed. Median (range) age was 53 (29-78) years. Four patients were <40years. Fourteen were men. Seven presented to a principal referral hospital, 13 to a major city or regional hospital. Seventeen arrived by ambulance. Headache peaked instantly in 9, between 1-24 hours in 5, and was worst ever in 11. Five had a past history of headaches, 4 of which were different from past episodes. Onset was during exertion in 5. GCS was 15 in 9. Loss of consciousness was witnessed in 9. Pain or stiffness was reported in 4, and neck stiffness was found on examination in 3. Neurological deficits were recorded in 5. All patients had ≥1 high risk Ottawa SAH rule variable. There were 4, 3, 2 and 1 high-risk variables in 2, 6, 8 and 6 patients, respectively. Conclusion: The Ottawa SAH rule appears to identify all cases of SAH in this small prospective state-wide casesseries.<br />