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Suspected pulmonary embolism with severe renal impairment — MRCEM SBA MCQ

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HardProcedures, imaging and diagnosticsSuspected pulmonary embolism with severe renal impairmentMRCEM SBA

A 69-year-old man presents with sudden pleuritic chest pain and breathlessness. His pulse is 112/min, blood pressure 126/78 mmHg and oxygen saturation 94% on air. He had knee replacement surgery 2 weeks ago and a pulmonary embolism 5 years ago. He has no leg pain or swelling, and his chest X-ray shows no alternative cause for his symptoms. His estimated creatinine clearance is 23 mL/min. He has no active bleeding or other contraindication to anticoagulation. CTPA is available now, but ventilation–perfusion single-photon emission CT (V/Q SPECT) is unavailable until tomorrow morning. What is the most appropriate diagnostic and initial treatment plan?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: C — Arrange V/Q SPECT tomorrow; anticoagulate pending imaging.

His two-level PE Wells score is at least 4.5: 1.5 points each for tachycardia, surgery within 4 weeks and previous PE. PE is therefore ‘likely’, so the diagnostic pathway proceeds to imaging rather than D-dimer testing. His creatinine clearance of 23 mL/min meets NICE’s threshold for severe renal impairment, for which suitability for V/Q SPECT should be assessed as an alternative to CTPA. Because that scan cannot be performed immediately, he should receive interim therapeutic anticoagulation while awaiting it; his haemodynamic stability and absence of a bleeding contraindication support this plan. The anticoagulant choice must take his renal impairment into account. Arrange baseline blood tests and review their results, without delaying interim treatment. ([nice.org.uk](https://www.nice.org.uk/guidance/ng158/chapter/Recommendations)) A overlooks the renal-imaging exception. B selects the appropriate scan but leaves a likely PE untreated during the delay; it would be reasonable if imaging were immediate. D is the pathway for PE-unlikely patients, not this patient. E could establish DVT if leg symptoms were present, but he has none, and a negative leg scan would not resolve the suspected PE.

Reference: NICE NG158: Venous thromboembolic diseases — recommendations (Last updated 2 August 2023) — https://www.nice.org.uk/guidance/ng158/chapter/Recommendations NICE NG158: Venous thromboembolic diseases — recommendation 1.1.18 (Last updated 2 August 2023) — https://www.nice.org.uk/guidance/ng158/chapter/Recommendations NICE NG158: Anticoagulation treatment for suspected or confirmed DVT or PE (Guideline last updated 2 August 2023) — https://www.nice.org.uk/guidance/ng158/resources/venous-thromboembolic-diseases-diagnosis-management-and-thrombophilia-testing-pdf-66141847001797