Clinical Assessment of Lower Extremity Discoloration

Essential History Questions

The American College of Cardiology recommends assessing for critical limb-threatening ischemia by asking about rest pain, non-healing wounds, and tissue loss, while simultaneously evaluating for infection in high-risk patients 1, 2
Patients should be asked about pain pattern and timing, including if pain occurs with walking a predictable distance and resolves within 10 minutes of rest, or if pain is present at rest, particularly at night requiring leg dependency for relief, as recommended by the American College of Cardiology and the European Heart Journal 1, 3
The European Heart Journal suggests inquiring about any non-healing or slow-healing wounds, ulcerations, or history of trivial trauma that preceded the discoloration 1, 3
The American College of Cardiology recommends determining actual walking ability before assuming the patient is "asymptomatic" 3

The American College of Cardiology recommends documenting if patient is ≥65 years, or ≥50 years with diabetes, smoking history, dyslipidemia, hypertension, or chronic kidney disease 1, 4
The American Heart Association, as published in Circulation, suggests asking about duration of diabetes, glycemic control, presence of neuropathy, and foot care practices, as diabetes increases PAD risk 2-4 fold and amputation risk 7-15 fold 5
Smoking exposure should be quantified, including pack-years and current status, as smoking increases PAD risk 2-6 fold, according to the American College of Cardiology and Circulation 5, 6
The American Heart Association, as published in Circulation, recommends asking about history of coronary artery disease, stroke, carotid disease, or renal artery stenosis, as one-third to two-thirds of PAD patients have concomitant coronary disease 5, 7

The American College of Cardiology recommends systematically palpating and grading bilateral femoral, popliteal, dorsalis pedis, and posterior tibial pulses 1, 5
The American Heart Association, as published in Circulation, suggests evaluating for color changes, temperature asymmetry, hair loss, trophic skin changes, hypertrophic nails, and integrity of intertriginous areas 1, 5
The European Heart Journal recommends checking for elevation pallor with extended capillary refill time and dependent rubor 3
If present, ulcer characteristics should be documented, including location, size, appearance, and signs of infection or gangrene, as recommended by the American College of Cardiology and the European Heart Journal 1, 3

The American College of Cardiology recommends measuring ankle-brachial index (ABI) immediately in all patients with discoloration and risk factors or abnormal pulse examination; ABI <0.90 confirms PAD, <0.6 indicates critical limb ischemia requiring urgent vascular evaluation 1, 2, 3
The European Heart Journal suggests obtaining toe-brachial index, toe pressures, or transcutaneous oxygen pressure (TcPO2) if ABI >1.40, as an alternative testing for medial calcinosis 2, 3

The American College of Cardiology recommends never applying compression therapy without first checking ABI, as this can precipitate gangrene in patients with PAD 2
The American Heart Association, as published in Circulation, suggests never attributing bilateral discoloration to "just venous stasis" without ruling out PAD and infection through objective testing 2
The European Heart Journal recommends recognizing "masked LEAD": Elderly patients with multiple comorbidities may present with sudden severe ischemia despite being labeled "asymptomatic" because they cannot walk far enough to develop claudication 3