Overview
Definition:
Femoral artery exposure refers to the surgical technique of accessing the common femoral artery (CFA), superficial femoral artery (SFA), and profunda femoris artery (PFA) for diagnostic or therapeutic interventions
These arteries are critical components of the lower extremity arterial supply.
Epidemiology:
Atherosclerotic occlusive disease affecting the femoropopliteal segment is common, with incidence increasing with age, smoking, diabetes, hypertension, and hyperlipidemia, necessitating frequent femoral artery interventions
Trauma to the groin can also lead to emergent exposure.
Clinical Significance:
Accurate and safe exposure of the femoral arteries is fundamental for a wide range of procedures including bypass grafting, endovascular interventions (angioplasty, stenting), embolectomy, arterial repair, and access for diagnostic angiography
Injury to these vessels can have severe consequences.
Anatomical Considerations
Inguinal Ligament:
The inguinal ligament forms the superior boundary of the femoral triangle
The CFA typically bifurcates into the SFA and PFA just inferior to the inguinal ligament.
Femoral Triangle:
Borders: inguinal ligament (superior), sartorius muscle (lateral), adductor longus muscle (medial)
The femoral artery, vein, and nerve lie within the femoral sheath in this triangle.
Common Femoral Artery:
Extends from the inguinal ligament to the bifurcation into SFA and PFA, typically at the level of the inguinal crease or slightly below
It is the main target for groin access.
Superficial Femoral Artery:
Continuation of the CFA, extending down the thigh, often becoming a more superficial structure as it courses within the adductor canal.
Profunda Femoris Artery:
Larger of the two terminal branches of the CFA, arising posterolaterally
It supplies the muscles of the thigh and is crucial for perfusion of the posterior compartment.
Relations:
The femoral vein lies medial and slightly posterior to the artery in the proximal thigh
The femoral nerve lies lateral to the artery and is outside the femoral sheath.
Indications For Exposure
Arterial Reconstruction:
Bypass grafting for femoropopliteal occlusive disease
Endarterectomy for severe atherosclerosis.
Endovascular Access:
Access for angiography, angioplasty, stenting, and atherectomy of the lower limb arteries.
Trauma:
Repair of direct arterial injury, pseudoaneurysm formation, or arteriovenous fistula.
Cannulation:
Rarely, for specific central venous access or arterial pressure monitoring in critical care settings.
Pulsed Ultrasound Guidance:
While not an indication for exposure, it is crucial for initial localization and planning of access.
Surgical Technique Of Exposure
Patient Positioning:
Supine position with the groin prepped and draped sterilely
A sandbag can be placed under the hip to improve exposure.
Incision:
A curvilinear or transverse incision centered over the anticipated course of the femoral artery, typically 2-3 cm distal to the inguinal ligament.
Dissection Planes:
Dissect through subcutaneous tissue and superficial fascia
Identify and divide the superficial fascia of the thigh
Retract saphenous vein if encountered and bothersome, taking care to preserve it if possible for potential graft conduit.
Identification Of Femoral Sheath:
The femoral sheath is identified as a glistening layer deep to the superficial fascia
It contains the femoral artery, vein, and lymphatic tissue.
Opening Femoral Sheath:
Carefully incise the anterior wall of the femoral sheath longitudinally, parallel to the artery
Identify the artery and vein within the sheath
Ligation and division of the superficial circumflex iliac artery and superficial epigastric artery may be necessary if they impede exposure.
Exposure Of Artery:
Dissect the artery meticulously from surrounding connective tissue using blunt and sharp dissection
Mobilize a sufficient length (e.g., 3-5 cm) for adequate manipulation
Carefully identify and protect the femoral vein, which lies medial.
Distinguishing Artery From Vein:
The artery is typically pulsatile and has thicker, paler walls than the vein
In case of doubt, palpation of pulse or Doppler ultrasound can confirm.
Identification Of Bifurcation:
Palpate or visualize the bifurcation of the CFA into the SFA and PFA
The SFA continues distally, while the PFA takes a more posterior and medial course
Selective exposure of SFA or PFA may be needed depending on the procedure.
Vessel Occlusion:
Apply vessel loops or bulldog clamps proximally and distally to occlude the artery to control hemorrhage and facilitate suturing or graft anastomosis
Care must be taken to avoid intimal injury.
Postoperative Care And Monitoring
Hemostasis:
Meticulous hemostasis is paramount
Ensure secure closure of the femoral sheath and subcutaneous tissues to prevent hematoma formation
Use drains if significant oozing is present.
Wound Care:
Clean, dry dressing
Monitor for signs of infection such as erythema, warmth, purulent discharge, and fever.
Pain Management:
Adequate analgesia, typically with opioids and/or NSAIDs.
Anticoagulation:
As per procedural indication (e.g., post-angiography, bypass grafting).
Limb Perfusion Monitoring:
Assess distal pulses (dorsalis pedis, posterior tibial), capillary refill, skin temperature, and sensation of the operative limb regularly
Doppler ultrasound can be used to confirm patency.
Ambulation:
Early ambulation is encouraged to prevent deep vein thrombosis (DVT) and pulmonary embolism (PE), but weight-bearing restrictions may apply depending on the procedure performed.
Complications
Early Complications:
Hematoma formation
Hemorrhage (groin or retroperitoneal)
Pseudoaneurysm formation
Arteriovenous fistula
Nerve injury (femoral nerve)
Wound infection
Deep vein thrombosis (DVT)
Arterial occlusion or thrombosis at the access site.
Late Complications:
Chronic limb ischemia due to graft occlusion or stenosis at the anastomosis
Incisional hernia
Lymphocele
Scarring and fibrosis leading to limited hip flexion.
Prevention Strategies:
Meticulous surgical technique, careful anatomical dissection, secure vessel control, appropriate suture material, effective hemostasis, early mobilization, and prophylactic measures for DVT and infection.
Key Points
Exam Focus:
Understand the arterial anatomy of the femoral triangle, the relationship between artery and vein, and the common bifurcation point
Know the indications for exposure and potential complications.
Clinical Pearls:
Use Doppler ultrasound for precise localization of the CFA before incision, especially in obese patients
Protect the femoral nerve and vein scrupulously during dissection
Avoid excessive retraction on the artery to prevent intimal damage
Consider the profunda femoris artery origin in cases of distal arterial disease requiring collateral flow.
Common Mistakes:
Mistaking the femoral vein for the artery
Inadvertent injury to the femoral nerve
Incomplete hemostasis leading to hematoma
Failure to identify and address significant collateral vessels
Over-retraction causing intimal dissection.