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CT Aortograms are one of the highest radiation scans performed in the emergency department. Conversely, aortic dissections are a known cause of unexpected death discovered on autopsy - hence the need to pick up dissections in ED without killing (too many) people with cancer causing ionizing radiation. While tests such as a D Dimer or Troponin will reduce the pre-test probability of an aortic dissection (chest / abdominal), they cannot be used to exclude it. Thus, the real question becomes whether there is a gestalt for an aortic dissection. If any of the screening questions below flag positive, it is not unreasonable to perform a CT aortogram. Note: The screening assessment below cannot be used to conclusively exclude aortic dissection - it only reduces the pretest probability. Hence, shared decision making between patient and a senior clinician needs to be documented if a CT aortogram is not performed.

Screening for High Risk Conditions:
No history of CTD (Marfan’s, Ehlers Danlos, Turner’s, Loeys-Dietz)
No FHx aortic dissection
No aortic valve disease
No recent aortic manipulation.
No known thoracic aortic aneurysm

Screening for High risk Pain features:
Patient reports pain in the chest/back/abdomen (cross location that does not apply)
Not sudden onset
Not described as “severe”
Not described as ripping/tearing/sharp in quality.

Screening for High risk Examination findings:
No pulse deficit (radial/radial, radial/femoral)
No significant sBP difference between upper limbs.
No focal neurological deficit
No new aortic murmur.