Suspected Pulmonary Embolism: Explaining the CT Scan
Your Role — Doctor
Emergency Department
Your 45-year-old patient presented with breathlessness and pleuritic chest pain after a long-haul flight. Assessment raises concern for a pulmonary embolism (a clot on the lung), and a CT pulmonary angiogram (CTPA) is needed. The patient is anxious and worried about the scan's radiation and dye, and frightened by the word clot. You need to explain the concern, the scan, and the plan, and start treatment appropriately.
- •Explain in plain terms why a clot on the lung is suspected, based on the symptoms and recent flight.
- •Explain what a CTPA scan is and why it's needed to confirm or rule out the clot.
- •Address concerns about the scan (radiation, contrast dye) honestly and proportionately.
- •Explain that treatment (blood-thinning injection) may be started while awaiting the scan, and why.
- •Reassure appropriately, outline the plan and next steps, and give safety information; check understanding.
The Interlocutor
Played by the actor / assessor
You are 45 and became breathless with a sharp chest pain a few days after a long flight. You are frightened by the word clot and worried it could be life-threatening. You're also nervous about having a CT scan because of the radiation and the injection of dye you've heard about.
- •Describe the breathlessness and sharp chest pain, worse when you breathe in, after your long flight.
- •React with fear to the word clot — ask if it could kill you.
- •Express worry about the CT scan's radiation and the dye injection.
- •Ask whether you'll need to be on blood thinners and for how long.
- •If the doctor explains clearly and reassures you about the scan and the plan, agree to the CTPA and to starting treatment.
Sample Role-play
Hello Ms Larsen, I'm Dr Boyd. Thanks for your patience. I'd like to explain what I'm concerned about and what I'd like to do next. Can you remind me how this started?
A few days after my flight back, I got really breathless and this sharp pain when I breathe in. It scared me.
Thank you — that's a really important pattern. Breathlessness and sharp, breathing-related chest pain after a long flight makes me want to rule out a clot travelling to the lung, which we call a pulmonary embolism. Long flights can occasionally set that off. I'm not saying you definitely have one, but it's important we check properly.
A clot on my lung? Can that kill you?
I understand that's a frightening thought. A large clot can be serious, which is exactly why we don't wait around and why you were right to come in. But many are small and very treatable, and we're catching this early. The key is to confirm it quickly and treat it, and that's what we're set up to do right now.
How do you even check for it?
With a scan called a CT pulmonary angiogram, or CTPA. It's a quick, detailed X-ray of the blood vessels in your lungs that shows a clot clearly. It takes only a few minutes, and it's the best test to confirm or rule this out.
I'm nervous about the radiation, and I heard they inject a dye?
Those are sensible things to ask about. The scan does use a small dose of radiation, but the benefit of finding or excluding a clot far outweighs that small risk. You're right that we inject a contrast dye through a vein to light up the vessels — most people just feel a warm flush for a moment. We'll check you have no kidney problems or allergies first. It's a very routine, safe test.
Okay. And if it is a clot — blood thinners? For how long?
Yes. In fact, because the suspicion is high, I'd like to start a blood-thinning injection now, before the scan, to be safe — we can always stop it if the scan is clear. If a clot is confirmed, you'd usually stay on a blood thinner for at least a few months, and we'd explain all of that. Treating it promptly is what keeps you safe.
Alright. That makes sense. Let's do the scan.
Thank you — that's the right decision. I'll arrange the CTPA now and start the injection. Let the staff know straight away if your breathing gets worse or you feel faint while you wait. I'll come and talk you through the results as soon as we have them.
Useful Phrases
Clinical Background
Suspected pulmonary embolism is risk-stratified (e.g., Wells score) with D-dimer and/or CT pulmonary angiography (CTPA), the definitive test. Recent long-haul travel is a provoking risk factor. Where clinical suspicion is high, empirical anticoagulation is started before imaging to prevent propagation. Counsel on CTPA (ionising radiation — justified by benefit; iodinated contrast — check renal function and allergies; transient warm sensation). Confirmed PE is treated with anticoagulation, typically for at least 3 months. Balance honest acknowledgement of seriousness with reassurance about prompt, effective treatment.
Common Mistakes to Avoid
- ✕Either alarming the patient about a potentially fatal clot or falsely minimising it, rather than giving balanced information.
- ✕Not addressing concrete concerns about radiation and contrast dye.
- ✕Failing to explain why anticoagulation may be started before the scan is done.