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Aortofemoral bypass surgery has been used in the management of aortoiliac occlusive disease since the 1950s. Today, revascularization with endovascular intervention has largely replaced aortofemoral bypass surgery and is accepted as first-line therapy. However, in cases where endovascular techniques are not appropriate, aortofemoral bypass continues to have an important role. Practitioners should be familiar with this technique, as it may be a viable option for patients who are not candidates for or have failed revascularization with endovascular intervention. This activity describes the relevant anatomy, indications, and contraindications and reviews important technical considerations of the aortofemoral bypass procedure. This activity highlights the role of the interprofessional team in caring for patients undergoing aortofemoral bypass surgery. Objectives: Identify the indications for aortofemoral bypass surgery. Review the contraindications for aortofemoral bypass surgery. Outline the steps involved in performing an aortofemoral bypass surgery. Explain the importance of interprofessional teamwork in ensuring the appropriate selection of candidates for aortofemoral bypass surgery and in providing effective post-operative management. Access free multiple choice questions on this topic.

Aortofemoral bypass surgery is a procedure utilized commonly for the treatment of aortoiliac occlusive disease, sometimes referred to as Leriche syndrome.[1] Aortoiliac occlusive disease can contribute to lower extremity ischemic symptoms necessitating intervention. Symptoms of patients with aortoiliac occlusive disease may include claudication, rest pain of the lower extremities, or ischemic ulcer formation on lower extremities due to inadequate blood flow. However, patients may also be asymptomatic. An ankle-brachial index is the most widely used test to determine peripheral arterial disease initially. Aortofemoral bypass surgery has aided in the management of aortoiliac occlusive disease dating back to the early 1950s. More recently, revascularization with endovascular interventions has supplanted the aortofemoral bypass surgery as first-line therapy. However, in cases where endovascular techniques are unsuccessful or inappropriate, aortobifemoral bypass still plays an important role and can even be considered the gold standard for long term patency.[2] This will discuss the relevant anatomy, indications, contraindications, as well as some important technique considerations.[3][4][5]

As with any surgical procedure, there exists a risk of bleeding or infection. In addition, there is a risk of wound infection, hematoma. Complications that result in significant morbidities include MI, renal dysfunction, and respiratory dysfunction. Late complications include hernias, graft thrombosis, and graft pseudoaneurysms, graft infections, aortoenteric fistulas further discussed below. Most frequently, (in 50% of cases), cardiac ischemia is responsible for death related to aortic reconstruction, which is because there are seldom patients with normal coronary arteries. Hence the importance of pre-operative screening and treatment and cardiac co-morbidities. Mortality related to cardiac death following surgical intervention is 1% to 2.5% in some centers.[19] Another common complication following surgery is renal insufficiency. This condition is typically a result of prolonged ischemia after clamping suprarenal, embolization secondary to clamping, hypoperfusion, hypovolemia or intrinsic renal artery disease. Often, this post-operative complication directly relates to the patient's preoperative cardiac and renal function. Knowing your patient's anatomy and having a precise plan preoperatively for clamping help reduce the incidence of renal insufficiency in the perioperative period.[19] Graft limb thrombosis happens in up to 30% of patients following aortobifemoral bypass. A higher incidence occurs with younger patients, female gender, and extra-anatomic bypasses and those who failed to quit smoking post-operatively. Typically this is unilateral limb thrombosis, which most often occurs due to continuous intimal hyperplasia or outflow disease.[28]

Graft limb thrombosis happens in up to 30% of patients following aortobifemoral bypass. A higher incidence occurs with younger patients, female gender, and extra-anatomic bypasses and those who failed to quit smoking post-operatively. Typically this is unilateral limb thrombosis, which most often occurs due to continuous intimal hyperplasia or outflow disease.[28] An anastomotic pseudoaneurysm occurs in 1% to 5% of cases as a late complication.[29][30]ypically pseudoaneurysms arise secondary to a weakening near the suture line and maybe a sterile process or the product of infection. The most common site is at the femoral anastomosis. Typically, symptoms include a slowly enlarging bulge in the groin or are discovered incidentally on imaging. If an infection is an underlying cause, the most common causative organism is the Staphylococcus species. Graft infection is associated with high morbidity and mortality.[31] Repair is the usual recommendation if larger than 2 cm, if aortic pseudoaneurysm is greater than 50% of graft diameter, or if the graft is infected.[29][30] If the graft is infected, excision is usually indicated. Aortoenteric fistula is a relatively rare occurrence but tends to be devastating and lethal if it occurs.[32] Mortality is at least 30% in most cases.[33] Typically it occurs secondary to an erosion of the proximal suture line on the aorta through the 3rd or 4th portion in the duodenum. It is often difficult to diagnosis because the triad of sepsis, abdominal pain, and GI bleeding are not always present. There may be a smaller, self-limited "herald-bleed" that occurs before any massive GI bleeding. CT scan with IV contrast and upper endoscopy are sometimes helpful in diagnosis. An important part of the patient's history will include the history of aortic surgery with graft placement. When found, emergency exploratory laparotomy is necessary with graft excision, debridement of infected tissue, bowel repair/resection, and extra-anatomic bypass or new graft placement. Even if surgery is successful, there is still high mortality associated with this complication.[32][33][34]

Multi-faceted approach with vascular trained physicians who are both skilled in minimally invasive procedures and open procedures would undoubtedly enhance the outcome of these patients. Also, appropriate pre-operative workup with physician evaluation from other specialties can also be necessary for improving patient outcomes in populations with co-morbid conditions (particularly, other cardiac, renal, or pulmonary co-morbidities). Radiologists with experience in reading vascular studies are also crucial for helping to determine the extent of disease accurately. Anesthesia is essential intraoperatively for monitoring of blood pressure and treatment of reperfusion hypotension. Specialty-trained nurses play a vital role in post-operative management and monitoring of the patient's hemodynamic status and urine output. They should assist the interprofessional team in coordination of care, patient and family education, and monitoring of the patient's progress; reporting any untoward changes in the patient's condition to the team. All these disciplines need to collaborate to guide cases to optimal outcomes. [Level V] The TASC II (Inter-Society Consensus for the Management of Peripheral Arterial Disease) recommends that patients be evaluated to undergo endovascular intervention first, if able (Level of Evidence B, Level III). Type A & B lesions in TASC classification are recommended to undergo endovascular therapy (Level of Evidence C, Level V). Whereas low-risk Type D lesions and low-risk surgical patients with Type C lesions are recommended to undergo surgical intervention (Level of Evidence C, Level V).[11]