A 62-year-old man is brought to the emergency department with pain and numbness in the right leg. He says "I was watching television 2 hours ago when the pain started, and then my leg became numb." Past medical history includes coronary artery disease with anterior wall myocardial infarction, ischemic cardiomyopathy, hypertension, and hyperlipidemia. He does not adhere regularly to prescribed medications. The patient does not smoke cigarettes but consumes alcohol occasionally. He appears to be in significant discomfort due to pain. His temperature is 36.7 C (98 F), blood pressure is 150/90 mm Hg, pulse is 102/min and regular, and respirations are 14/min. Physical examination shows a cool right lower extremity with delayed capillary refill. Even with Doppler examination, no pulses are detected at the right popliteal and dorsalis pedis arteries. Which of the following is the best next step in the management of this patient?

Question

A 62-year-old man is brought to the emergency department with pain and numbness in the right leg.  He says "I was watching television 2 hours ago when the pain started, and then my leg became numb."  Past medical history includes coronary artery disease with anterior wall myocardial infarction, ischemic cardiomyopathy, hypertension, and hyperlipidemia.  He does not adhere regularly to prescribed medications.  The patient does not smoke cigarettes but consumes alcohol occasionally.  He appears to be in significant discomfort due to pain.  His temperature is 36.7 C (98 F), blood pressure is 150/90 mm Hg, pulse is 102/min and regular, and respirations are 14/min.  Physical examination shows a cool right lower extremity with delayed capillary refill.  Even with Doppler examination, no pulses are detected at the right popliteal and dorsalis pedis arteries.  Which of the following is the best next step in the management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_be30_c370_8f63_bb61cde50b9e_MD0005_00 This patient has acute limb ischemia (ALI) with an immediately threatened extremity. ALI is defined as a sudden decrease in limb perfusion and is most often caused by acute arterial occlusion due to systemic embolism from a cardiac source (eg, atrial fibrillation, left ventricular thrombus, or septic emboli from infective endocarditis). Patients typically have the six P's of acute ischemia: pain, pallor, paresthesia, pulselessness, poikilothermia, and paralysis. Patients with ALI with threatened viability of the limb have severe pain (rest pain) with sensory and/or motor loss, delayed capillary refill, and inaudible arterial Doppler signals. All patients with clinical signs and symptoms of ALI should receive anticoagulation (ie, intravenous heparin bolus followed by continuous heparin infusion) immediately while awaiting further interventions. Anticoagulation prevents thrombus propagation and formation of new distal thrombus due to stasis. Patients with an immediately-threatened extremity are at increased risk for irreversible myonecrosis within 4-6 hours and should have emergency surgical revascularization. (Choice A) Noninvasive vascular imaging with duplex ultrasonography, CT angiography, or magnetic resonance angiography is a reasonable option for patients with viable ALI that is not under immediate threat of tissue necrosis. Such patients typically have intact arterial and venous Doppler signals and no sensory or motor deficits. However, patients with immediately-threatened limbs need urgent surgical revascularization to salvage the limb; obtaining further vascular imaging would lead to an unnecessary delay in definitive care. (Choice C) Observation is not recommended as any further delay in immediate revascularization may result in acute limb necrosis. Prophylactic antibiotics are usually given within 1 hour of surgical revascularization procedures involving groin incisions and are not indicated at this time. (Choice D) Patients with an ischemic but viable extremity on examination can be managed with catheter-based thrombolytic therapy or surgical revascularization. Catheter-based intra-arterial administration has better clinical outcomes and fewer bleeding complications than intravenous administration of thrombolytic agents. However, this patient has a threatened lower extremity and should be managed with emergency surgical revascularization. (Choice E) Transthoracic echocardiogram is not indicated at this time but may be obtained later as part of a comprehensive diagnostic evaluation. Educational objective: Patients with an immediately-threatened extremity (severe pain, delayed capillary refill, absent arterial Doppler signals, and sensory or motor deficits) are at risk for irreversible myonecrosis within 4-6 hours and should have anticoagulation and emergency surgical revascularization. References: Antithrombotic therapy in peripheral artery disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/22315275) Analysis of associated diseases in patients with acute critical lower limb ischemia. (http://www.ncbi.nlm.nih.gov/pubmed/23534299)

A 62-Year-Old Man Is Brought to the Emergency Department with Pain