Acute Limb Ischemia

A 62-year-old man with a history of diabetes and hypertension presents with acute onset of severe right lower limb pain and coldness. On examination, the limb is pale and pulseless below the right inguinal ligament. Duplex ultrasound confirms acute thrombosis of the right superficial femoral artery. Which of the following is the most appropriate initial management?

A 55-year-old man with a history of diabetes and smoking presents with acute onset of right foot pain and pallor 6 hours after sudden onset. On examination, the foot is cold, pale, and pulseless. Sensory examination reveals loss of light touch and pain sensation in the foot. Motor power is 3/5 in foot dorsiflexion. Femoral pulse is palpable but faint. What is the most appropriate immediate next step?

A 62-year-old man with atrial fibrillation presents with acute onset of severe pain and coldness in the right lower limb. Clinical examination reveals absent pulses and mottled skin. What is the most common cause of acute limb ischemia in this patient?

A 62-year-old woman with a 10-year history of intermittent claudication in the right leg now presents with acute onset rest pain, pallor, and sensory loss in the foot. Which single clinical finding most reliably distinguishes acute-on-chronic ischemia from acute embolic ischemia in this patient?

A 55-year-old woman with a 10-year history of diabetes mellitus and hypertension presents with a 3-day history of progressive pain and coldness in her right foot. She reports no prior claudication. On examination, the right foot is mottled and cyanotic, with absent pulses below the popliteal artery. Sensory examination shows diminished sensation in the foot and lower leg. Motor examination reveals mild weakness of foot dorsiflexion. Capillary refill is markedly delayed. What is the most likely underlying mechanism of limb ischemia in this patient?