What is the management approach for a patient presenting with a pseudoaneurysm of the femoral artery?

Management of Femoral Artery Pseudoaneurysm

For femoral artery pseudoaneurysms, management is determined by size: small pseudoaneurysms (<2.0 cm) can be observed with ultrasound follow-up, while larger pseudoaneurysms (≥2.0 cm) should be treated with ultrasound-guided thrombin injection as first-line therapy, reserving surgical repair for failures, symptomatic cases, or urgent complications. 1, 2

Immediate Diagnostic Approach

• Obtain duplex ultrasound imaging immediately when pseudoaneurysm is suspected, as physical examination alone misses more than 60% of catheter-related pseudoaneurysms 2, 3
• Ultrasound defines the size, vessel injury, patency, degree of clotting, and communication with the femoral artery 2, 4
• Monitor specifically for: pulsatile groin mass, expanding hematoma, distal limb ischemia, compressive symptoms, femoral bruit, palpable thrill, or signs of retroperitoneal bleeding 2, 5
• Place pulse oximetry on the affected foot to provide early warning of arterial obstruction 2
• Verify coagulation parameters, particularly if patient received heparin, and wait until ACT falls to 150-180 seconds or aPTT to 50 seconds before intervention 2

Size-Based Treatment Algorithm

Small Pseudoaneurysms (<2.0 cm)

• Conservative management with observation is appropriate, as 61% resolve spontaneously within 7-52 days and only 11% ultimately require surgical intervention 2, 4
• Re-evaluate with duplex ultrasound at 1 month after the original injury 1, 2
• 90% of small pseudoaneurysms that close spontaneously do so within 2 months 2
• If still present at 2 months follow-up, consider more definitive treatment 6

Large Pseudoaneurysms (≥2.0 cm)

• Ultrasound-guided thrombin injection is the preferred initial treatment, achieving 93% aggregate success rate 2, 3, 7
• Inject 100-3000 international units of thrombin under ultrasound guidance 2, 6
• Rare complications include distal thromboembolism (<2% of cases) 2, 6
• Surgical repair is reasonable for pseudoaneurysms ≥2.0 cm that persist or recur after ultrasound-guided compression or thrombin injection 1, 6

Absolute Indications for Urgent Surgical Repair

These conditions require immediate surgical intervention regardless of pseudoaneurysm size:

• Rupture into retroperitoneal space or upper thigh 2, 3
• Venous thrombosis from compression of adjacent femoral vein 2
• Painful neuropathy from femoral nerve compression 2, 5
• Skin erosion or expanding rupture into adjacent soft tissue 1, 2
• Infected femoral pseudoaneurysms (require extensive operative debridement, often with autogenous in situ reconstruction or extra-anatomic bypass grafts) 1, 3
• Active hemorrhage or unexplained anemia requiring transfusions 3

Special Clinical Scenarios

Anastomotic Pseudoaneurysms

• Anastomotic pseudoaneurysms should undergo repair (Level of Evidence: A) 1
• These occur with 2-5% incidence as late complications of synthetic aortofemoral bypass grafting 1
• They inevitably continue to enlarge if left untreated and may require arteriography before repair 1

Deep Femoral Artery Pseudoaneurysms

• Deep femoral artery pseudoaneurysms have higher rupture rates (33%) compared to other lower extremity pseudoaneurysms, emphasizing need for prompt diagnosis and treatment 2, 3
• Endovascular coil embolization is the preferred initial intervention for profunda femoris pseudoaneurysms, particularly in poor surgical candidates 3

Tense Hematomas

• Tense hematomas may require surgical evacuation/repair to prevent local pressure effects, particularly when causing compressive symptoms 2
• Hemorrhage associated with the femoral route may be concealed in the retroperitoneum 2

Anticoagulated Patients

• Interventional radiologists and surgeons should be consulted before removing larger devices or any arterial catheter in an anticoagulated patient 2

Critical Pitfalls to Avoid

• Never rely on physical examination alone - maintain a low threshold for duplex ultrasound, as clinical examination is unreliable and misses >60% of cases 2, 3, 4
• Avoid premature intervention on small pseudoaneurysms - recognize that most <2.0 cm resolve spontaneously, avoiding unnecessary procedures 2
• Do not miss retroperitoneal bleeding - hemorrhage associated with the femoral route may be concealed in the retroperitoneum 2
• Do not delay imaging - imaging should always be obtained when vascular injury is suspected 2, 5