Beyond the Threatened Limb: Acute Limb Ischemia as a Diagnostic Attractor

Acute limb ischemia is a time-sensitive vascular emergency, but in older patients with active cancer and multimorbidity, the threatened limb can become a diagnostic attractor: a correct specialized diagnosis that narrows attention before whole-patient physiology is integrated.We report an 81-year-old man with metastatic cecal adenocarcinoma receiving folinic acid, fluorouracil, and oxaliplatin (FOLFOX) who presented on day one with three days of progressive left lower limb claudication, coldness, discoloration, absent pulses, preserved motor and sensory function, and no rest pain.The presentation was clinically compatible with Rutherford I-IIa acute limb ischemia; bedside Doppler signals were not documented, precluding a definitive retrospective distinction between these categories.Concurrent findings included new atrial fibrillation, basal crackles, peripheral edema, markedly elevated N-terminal pro-B-type natriuretic peptide and troponin, bilateral pleural effusions, and radiological concern for low cardiac output.Computed tomography angiography (CTA) showed severe distal superficial femoral artery stenosis, long popliteal occlusion, slow distal flow, and limited runoff, favoring an acute-on-chronic ischemic process.On day two, a 6 mm x 60 mm covered stent was placed across the distal superficial femoral artery lesion.The treated lesion had a satisfactory technical result, but distal runoff remained severely compromised.Therapeutic anticoagulation initiated on day one was not maintained; discharge treatment on day three included prophylactic-dose enoxaparin and aspirin, with no rationale for the change documented in the available record.He returned on day five with recurrent coldness and toe necrosis despite normal lactate.No repeat vascular imaging was available to define the mechanism.Care became palliative on day 13, and he died on day 58.This case illustrates that a correct vascular diagnosis should not terminate integrative emergency reasoning.We propose that a vascular-plus-physiology cross-check may help preserve attention to systemic physiology and goals of care, but it is an educational framework rather than a validated clinical algorithm.