Understanding changing clinician behaviour regarding CT scan use is essential when considering design and implementation of a rule-out pathway for AAS.

The study will assess AAS prevalence and patient demographics in Lothian, length of hospital stay and mortality rates. It will also evaluate the following trends over time:
● Emergency CTA use and positivity rates for the detection of AAS.
● Emergency CTPA use and incidental rates for the detection of AAS.
● Percentage of patients with incidental detection of AAS on CTPA going on to have CTA.
● Use of the biomarker D-dimer in the work-up of AAS.

Pending Grant Funding