Femorofemoral Bypass
Exposure of femoral arteries
Bilateral exposures of the femoral arteries are obtained in standard longitudinal or oblique fashion. Longitudinal incisions afford better access to both proximal and distal femoral arteries, especially if the deep femoral (profunda femoris) artery is deemed the main outflow vessel.
The incision is carried along the femoral pulse at the level of the common femoral artery (inguinal ligament). Subcutaneous tissues are dissected and the femoral sheath entered. The artery lies lateral to the femoral vein. The common, superficial, and deep femoral arteries are dissected and controlled. Circumflex branches are controlled and preserved.
Tunneling of graft
Before systemic heparinization, subcutaneous tunneling or tunneling in the space of Retzius (preperitoneal) is performed. Tunneling of the femorofemoral bypass can be challenging because one must pay careful attention to the geometry of the graft lie in order to avoid undue tension and kinking of the graft at the graft-to-artery anastomoses.
The graft is tunneled from one groin incision to the other by using blunt finger dissection, a large clamp, or a graft tunneling device over the prefascial subcutaneous plane within the abdominal wall superior to the pubis (see the image below).
At times, the graft may have to be tunneled in the preperitoneal plane (space of Retzius) because of damaged skin, abdominal scarring, or other abdominal wall conditions that prohibit the use of the prefascial subcutaneous plane. Care must be taken in the preperitoneal tunneling to avoid visceral injury, namely to the bowel or bladder. The polytetrafluoroethylene (PTFE) or Dacron graft is then passed through the tunnel and configured as an inverted C or U so that the graft is directed longitudinally at the anastomoses (see the image below).
Femoral anastomoses
The patient is systemically heparinized, and vascular clamps are applied thereafter. In nearly all cases, the anastomoses are fashioned in an end-to side configuration (see the image below).
If the external iliac artery is occluded, however, an end-to-end configuration may create a better lie of the bypass. A longitudinal arteriotomy is created to some component of the femoral arterial system, depending on the quality of the inflow and outflow artery. The graft is spatulated accordingly. The inflow anastomosis is typically to the common femoral artery. If significant disease of the superficial femoral artery exists in the outflow femoral system, the anastomosis may have to be performed in such a manner as to incorporate the deep femoral artery.
In general, spatulation of the anastomosis onto the deep femoral artery is recommended. Concomitant endarterectomy of the femoral artery may be indicated if significant disease exists. It is important to allow some redundancy of the graft so that unfavorable geometry does not occur with bending at the lower abdomen. The graft is flushed well before the completion of the anastomoses, and enhanced flow is confirmed with Doppler examination in the recipient femoral system, as well as continued flow in the outflow vessels distal to the donor femoral artery.
Postoperative Care
Perioperative hemodynamic monitoring is essential to good outcomes. In view of the prosthetic burden, surgical wounds should be monitored diligently for early signs of infection, which should be managed promptly. Prophylactic antibiotics should be administered prior to future surgical intervention that may disseminate bacteria, such as dental procedures.
Complications
Complications of femorofemoral bypass include the following:
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Femoral nerve injury
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Hematoma
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Graft thrombosis and distal emboli
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Graft infection [14]
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Early graft thrombosis and delayed pseudoaneurysm of the graft may be a sign of underlying graft infection
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Tunneling of the femoral-femoral bypass.
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Femoral-femoral bypass configuration.
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End-to-side graft to femoral anastomosis.