General Surgery · Year 3 · from General Surgery

Case 1: Acute Limb Ischemia

Patient Demographics

  • Age: 72 years
  • Sex: Male
  • Occupation: Retired banker

Chief Complaint

"My left leg suddenly became cold and painful 4 hours ago."

History of Present Illness

The patient reports sudden onset of severe left leg pain that began 4 hours ago while watching television. The pain started in his calf and rapidly progressed to involve his entire leg. He noticed his leg became pale and cold. He is unable to move his toes. He has no history of claudication or peripheral vascular disease. He does have a history of atrial fibrillation and admits to being non-compliant with his anticoagulation.

Past Medical History

  • Atrial fibrillation (diagnosed 2 years ago)
  • Hypertension
  • Type 2 diabetes
  • On warfarin but INR frequently sub-therapeutic (non-compliance)

Medications

  • Warfarin (non-compliant)
  • Metoprolol 50 mg BID
  • Lisinopril 20 mg daily
  • Metformin 1000 mg BID

Physical Examination

  • Vitals: BP 148/92, HR 88 (irregular), RR 18, Temp 36.8°C
  • Cardiac: Irregularly irregular rhythm
  • Left lower extremity:
  • Pale, cool to touch from mid-thigh distally
  • No palpable pulses (femoral weak, popliteal/DP/PT absent)
  • Absent ankle-brachial index (not measurable)
  • Decreased sensation below knee
  • Unable to wiggle toes (paralysis)
  • No muscle tenderness on palpation (yet)
  • Right lower extremity: Normal pulses, warm, normal sensation

The Six P's of Acute Limb Ischemia

  1. Pain: Severe, sudden onset ✓
  2. Pallor: Pale leg ✓
  3. Pulselessness: Absent distal pulses ✓
  4. Paresthesias: Decreased sensation ✓
  5. Paralysis: Cannot move toes ✓
  6. Poikilothermia: Cold leg ✓

Rutherford Classification

Class IIb - Threatened (marginally salvageable)

  • Sensory loss beyond toes
  • Mild-moderate motor deficit
  • Requires urgent revascularization

Laboratory Results

  • INR: 1.3 (sub-therapeutic)
  • Creatinine: 1.2 mg/dL
  • CK: 340 U/L (mildly elevated)
  • Lactate: 2.8 mmol/L
  • Hemoglobin: 13.4 g/dL
  • ECG: Atrial fibrillation with controlled rate

Imaging

CT Angiography (rapid):

  • Filling defect in left common femoral artery
  • No flow beyond proximal superficial femoral artery
  • Embolic occlusion pattern (abrupt cutoff, no collaterals)
  • No significant atherosclerotic disease
  • Right leg: Patent arterial tree

Diagnosis

Acute limb ischemia, Rutherford Class IIb, likely cardioembolic (atrial fibrillation)

Management

Given Class IIb limb ischemia (threatened but salvageable):

  • Immediate heparinization: IV heparin bolus + infusion
  • Urgent surgical revascularization
  • Time is critical: "Time is tissue"

Operative Procedure

Emergency surgical embolectomy:

  • General anesthesia
  • Groin incision, exposure of common femoral artery
  • Longitudinal arteriotomy
  • Passage of 4F and 3F Fogarty balloon catheters
  • Extraction of organized thrombus from SFA and popliteal
  • Excellent back-bleeding and in-flow established
  • Completion angiogram: Restored flow to tibial vessels
  • Arteriotomy closure
  • Fasciotomies NOT performed (reperfusion time <6 hours, no compartment syndrome)

Postoperative Management

  • Heparin continued, transitioned to warfarin
  • Monitor for reperfusion injury
  • Serial CK levels (peaked at 2,400 U/L, trended down)
  • Urine output monitored (myoglobin clearance)
  • Foot elevated, warm

Postoperative Course

  • Leg warm, pink, pulses palpable
  • Sensation returning
  • Motor function improving
  • No compartment syndrome
  • Discharged POD 4 on warfarin (goal INR 2-3)

Long-term Management

  • Lifelong anticoagulation for atrial fibrillation
  • Cardiology follow-up
  • Patient education on medication compliance
  • INR monitoring clinic enrollment

Teaching Points

  1. Acute limb ischemia is a vascular emergency
  2. "Six P's" for clinical diagnosis
  3. Rutherford classification guides management urgency
  4. Embolism (cardiac source) vs. thrombosis (atherosclerotic) have different implications
  5. Immediate anticoagulation with heparin
  6. Revascularization method depends on etiology and presentation
  7. Monitor for reperfusion injury and compartment syndrome

Clinical Image

Image Description: CT angiography demonstrating acute arterial occlusion of the superficial femoral artery. The abrupt cutoff of contrast with minimal collateral formation is characteristic of an acute embolic event.

Attribution: Image from Wikimedia Commons, Category:Computed tomography angiography. Source: https://commons.wikimedia.org/wiki/Category:Computed_tomography_angiography

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