Acute Limb Ischemia and Venous Thromboembolism
A 64-year-old man has a cold, painful left leg. The limb is pale and pulseless with reduced foot power. Angiography shows superficial femoral artery occlusion, and catheter-directed thrombolysis restores a dorsalis pedis pulse. He is kept on bed rest with the leg immobilized for 4 days, and thromboprophylaxis is withheld because of oozing at the femoral puncture site. Which complication is he at greatest risk of during this admission?
- A.Pulmonary embolismCorrect
- B.Acute ischemic stroke
- C.Acute mesenteric ischemia
- D.Aortic dissection
Explanation
Prolonged immobility, an inflamed and recently instrumented lower limb, endothelial injury from the arterial sheath, and omission of pharmacological prophylaxis together complete Virchow triad of stasis, endothelial injury and hypercoagulability, so deep vein thrombosis with subsequent pulmonary embolism is the dominant in-hospital risk. Reperfused ischemic limbs are particularly prone to venous thrombosis because of swelling, compartment pressure and pain-limited mobility. Pulmonary embolism should be suspected if he develops sudden breathlessness, pleuritic pain, tachycardia or unexplained hypoxia, and computed tomography pulmonary angiography is the confirmatory test. Ischemic stroke is a risk for patients with atrial fibrillation, carotid disease or cardiac thrombus, none described here, and thrombolysis delivered locally into a leg artery does not embolize to the brain. Mesenteric ischemia would require an embolic source or profound low flow and typically presents with pain out of proportion to examination, which is not the expected complication of leg immobility. Aortic dissection relates to hypertension and connective tissue disease rather than immobility after thrombolysis. Mechanical prophylaxis with intermittent pneumatic compression should be used while bleeding risk precludes heparin, and pharmacological prophylaxis restarted as soon as the puncture site is dry. Reperfusion also mandates monitoring for compartment syndrome, hyperkalemia, myoglobinuria and acute kidney injury.
Why each option
- A.
- Correct. Immobility, venous stasis, endothelial injury and withheld prophylaxis make deep vein thrombosis with pulmonary embolism the leading in-hospital risk.
- B.
- Stroke would require a cardiac or carotid embolic source; local arterial thrombolysis in the leg does not embolize to the brain.
- C.
- Mesenteric ischemia requires an embolic source or a low-flow state and is not a consequence of leg immobility.
- D.
- Aortic dissection is driven by hypertension and connective tissue disorders, not by post-thrombolysis bed rest.
Reference: UpToDate 2025, Prevention of venous thromboembolism in acutely ill hospitalized adults
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