A 65-year-old man is brought to the emergency department after a motor vehicle collision. The patient was the restrained front passenger in a car that skidded on ice and hit a tree at 25 miles/hr. His right leg was pinned under the dashboard, and extrication took 2 hours. The patient has continued right leg pain, which is minimally relieved with morphine. He had a myocardial infarction 6 months ago for which he takes aspirin and clopidogrel. Blood pressure is 102/72 mm Hg and pulse is 111/min. On physical examination, the patient is mildly sedated. The right leg appears swollen, bruised, and shiny. Sensation is intact. Passive motion of the right ankle and toes causes pain. Bilateral pedal pulses are palpable. X-ray of the right lower extremity is negative for fracture. Which of the following is the best next step in management of this patient's leg pain?

Question

A 65-year-old man is brought to the emergency department after a motor vehicle collision.  The patient was the restrained front passenger in a car that skidded on ice and hit a tree at 25 miles/hr.  His right leg was pinned under the dashboard, and extrication took 2 hours.  The patient has continued right leg pain, which is minimally relieved with morphine.  He had a myocardial infarction 6 months ago for which he takes aspirin and clopidogrel.  Blood pressure is 102/72 mm Hg and pulse is 111/min.  On physical examination, the patient is mildly sedated.  The right leg appears swollen, bruised, and shiny.  Sensation is intact.  Passive motion of the right ankle and toes causes pain.  Bilateral pedal pulses are palpable.  X-ray of the right lower extremity is negative for fracture.  Which of the following is the best next step in management of this patient's leg pain?

Quizplus · Accepted Answer

11ec25c8_d85a_d0c0_bc81_2fd63d46e389_MD0003_00 This patient has severe lower extremity pain worsened on passive stretch of the calf muscles. In light of the acute trauma and concurrent antiplatelet medications, which may cause occult bleeding in tissues, this presentation is concerning for compartment syndrome (CS). CS is a limb-threatening condition caused by increased pressure within an enclosed fascial space that limits perfusion of muscle and nerve tissues. Although frequently associated with trauma with fracture, other common causes of CS include crush injury, severe burns, and arterial reperfusion procedures; patients who are on anticoagulation or have a bleeding diathesis are at increased risk. In addition to severe pain (classically out of proportion to the injury), other possible features include paresthesias, loss of sensation, motor weakness, and diminished pulses. fascial space However, although CS can often be a clinical diagnosis, not all features may be present early in the course, and pain medications may mask the symptoms. Clinicians must maintain a high index of suspicion. Surgeons often choose to confirm the diagnosis by measuring compartment pressures (eg, needle manometry); a delta pressure (diastolic blood pressure − compartment pressure) ≤30 mm Hg is suggestive of CS. Definitive management includes urgent fasciotomy (although some patients with mild CS may be managed conservatively with close observation if compartment pressures are falling and delta pressures are rising). Compartment pressure measurement can also help avoid unnecessary fasciotomies in patients in whom CS is one of the differential diagnoses under consideration. (Choice A) Compression wraps of the calf are typically used for edema caused by chronic venous insufficiency, especially when associated with additional complications (eg, stasis dermatitis). However, they would increase pressure within the fascial compartments and are not recommended for this patient. (Choices C and E) Arteriography provides detailed arterial mapping and is helpful when preparing for revascularization procedures. Lower extremity Doppler studies can identify arterial occlusion. Although this patient has known atherosclerotic disease, his palpable pulses suggest that this is not the cause of his acute pain. These studies are not useful in the diagnosis of CS. (Choice D) CT scan of the lower extremity is unlikely to be helpful acutely in this patient with no fracture noted on x-ray. (Choice F) Lower extremity traction is used for short-term management of fractures and dislocations. It is not useful in CS, and this patient's x-ray does not show a fracture. Educational objective: Compartment syndrome is caused by increased pressure within an enclosed fascial space that limits perfusion. Common causes include fracture, crush injury, severe burns, and arterial reperfusion procedures; patients who are on anticoagulation or have a bleeding diathesis are at increased risk. Clinical features include pain, paresthesias, loss of sensation, and motor weakness. Diagnosis is confirmed by measuring compartment pressures. References: Acute compartment syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/27241376)

A 65-Year-Old Man Is Brought to the Emergency Department After