Thunderclap headache (TCH) is a concerning symptom and requires diagnostic evaluation. Initial head CT w/o contrast can help detect SAH with negative LR of 0.01 if performed within 6h of headache onset. However, a head CT w/o contrast can miss other causes of TCH and may require advanced imaging and LP.
The application of the Ottawa SAH rule in this relatively small sample of patients had a 100% sensitivity for identifying SAH in the ED but a lower 95% confidence interval of 78.2. The 100% negative predictive value, with a promising 95% CI of 98.6-100%, may have been driven by the lower prevalence of SAH in this study population compared to a previous validation study.
Positive responses to "red flag" screening questions for back pain warranted further investigation, though the positive predictive value was poor. Negative responses to screening "red flag" questions were useless as a screening tool for ruling out serious disease, such as fracture, infection, malignancy, or cauda equina.
Among patients with ICH, those on non-vitamin K oral anticoagulants had a lower in-hospital risk of mortality compared to warfarin (26.5% vs 32.6%). Compared to warfarin, those on NOACs were more likely to be discharged home (+3.3%), be functionally independent (+2.5%), and have the ability to ambulate independently at discharge (+1.8%).