27th May 2025

Question Topic: EM

A 64-year-old lady presents to the Emergency Department with acute onset shortness of breath and pleuritic chest pain. She had returned from North America 24 hours ago and experienced progressive shortness of breath on exertion since getting off the plane. Her only past medical history is breast cancer, for which she remains on daily hormone therapy. On examination, her respiratory rate is 20 breaths/ minute, oxygen saturations 97% on 4L oxygen via nasal cannula, and her respiratory examination is normal. 

Investigations: 

Chest x-ray: Reported by radiologist as normal.

Given this lady’s presentation, what is the most appropriate next step in her management strategy to confirm the likely diagnosis? 

Select the SINGLE most appropriate option from the list below. Select ONE option only.