What are the differential diagnoses and how would investigate them?
The history and examination findings are classic of aortic dissection, with chest and back pain featuring in up to 80% of presentations (1).
A full blood panel including a venous gas should be sent. D-dimer is also a useful marker and is raised more rapidly in aortic dissection than other differentials such as pulmonary embolus (1, 2).
An ECG would be useful to consider pericarditis or acute coronary syndrome.
Whilst most patients will undergo a chest x-ray in the first instance, computerised tomographic angiography (CTA) is the gold standard investigation. Transoesophageal ultrasound is a second line alternative if the patient is too unstable to transfer out of resus (3).