Aortobifemoral bypass by Sagar S. Gandhi, MD

Operative Steps

Aortobifemoral bypass may be performed via either a transperitoneal or a retroperitoneal approach. Transperitoneal approach will be discussed here.

Femoral exposure

Vertical skin incisions are started in each groin 1/3 of the way between the pubic symphysis and the anterior superior iliac spine and extended caudally.
The incision is deepened through the subcutaneous tissues with electrocautery.
The encountered lymphatics are ligated and divided to prevent postoperative lymph leaks.

The femoral sheath is incised, and the common femoral artery is then exposed and sharply dissected circumferentially.

The dissection is extended proximally to the inguinal ligament and distally to include the superficial femoral and profunda femoris arteries.

The common femoral, superficial femoral and profunda femoris arteries are encircled with Silastic vessel loops.

Abdominal exposure

The ligament of Treitz is identified and incised to mobilize the duodenum and further retract it to the right. small bowel is then wrapped in a moistened towel.

The aorta is then exposed by incising its overlying retroperitoneum. The incision is continued proximally to the level of the left renal vein. If the inferior mesenteric vein is encountered, it can be ligated and divided.

The infrarenal aorta is then sharply dissected and evaluated for adequacy of clamping. Left renal vein may require cephalad retraction.

Once the aorta and femoral vessels are dissected out, tunneling is performed.
Using gentle finger dissection, a tunnel is started from the groin incision anteriorly along the course of the common femoral.
The second end of the tunnel is similarly created from the abdominal incision anteriorly following the course of the common iliac artery.
The tunneling is performed such that the graft is lying posterior to the ureter to prevent any future entrapment of the ureter.
With an index finger placed from each end of the tunnel, gentle finger dissection is continued until both fingertips meet.
A tunneling clamp is carefully introduced in the tunnel from the groin and an umbilical tape is retrieved to provide easy access to the tunnel at a later stage.
The same is performed on the other side.
Intravenous systemic heparin is given prior to clamping the blood vessels.

Proximal anastomosis

Dacron or ePTFE graft is selected. Common size of the bifurcated graft is 16 X 8 mm or 14 X 7 mm.
Options for proximal anastomosis include End to end anastomosis or end to side anastomosis.

The proximal clamp is applied at the selected clamp site, typically the intrarenal aorta.
For an end-to-end anastomosis is planned, the aorta is divided at least 1.5cm distal to the renal arteries. The aorta transection should be beveled so that the posterior aortic wall is slightly longer and therefore easier to visualize. The anterior aortic wall can also be spatulated.

Cephalad retraction of the left renal vein may be required for better exposure.
Distal control may be required if there is back bleeding from the distal aorta. The distal aorta can be clamped if necessary.

The proximal anastomosis is constructed using a 3-0 Prolene™ Polypropylene suture starting in the posterior wall and continuing to the front with both needles. Take large bites of the native aorta to ensure that the anastomosis will be secure.

To assess the patency of the proximal anastomosis, clamp the distal graft and gently release the proximal aortic clamp.
- NOTE: Repair all leaks at this stage. In rupture cases where there is needle hole or mild anastomotic bleeding, an adjunctive hemostat product such as EVARREST™ Fibrin Sealant Patch can be used.
- NOTE: For ABF, the distal aortic end is oversewn with a running 3-0 Prolene™ Polypropylene suture or can be stapled closed with a vascular load. If performing AAA, a tube graft is used, and a distal anastomosis is performed to the aortic bifurcation in an end-to-end fashion, using a 3-0 Prolene™ Polypropylene suture.

Distal anastomosis

Tunnel the graft limbs into the groin area. Pass a long-curved clamp from each groin and bring the graft into the retroperitoneum on each side. Take care when creating the tunnel. Ensure there is no kinking or twisting of the graft limbs.

Place clamps on the proximal common femoral artery, superficial femoral artery, and deep femoral artery.

Create a small (2-2.5 cm) common femoral arteriotomy and bevel the limb of the graft to match the length of the anastomosis.
A common femoral endarterectomy may be required and if there is any disease at the bifurcation of the common femoral artery, extension of the arteriotomy onto the profunda femoral artery should be considered.

Perform the end to side anastomosis with a 5-0 Prolene™ Polypropylene suture. Before tying the anastomosis, carry out flushing maneuvers to remove emboli and air bubbles by removing the distal clamps to allow back bleeding.

Gently remove the clamp from the proximal aorta, then remove one clamp at a time from each groin.

Reinspection of all the suture lines is performed to ensure adequate hemostasis. Reverse the heparin with protamine and use adjunctive hemostats such as SURGICEL SNoW™ Absorbable Hemostat as needed.

Remove the retractors and allow the bowel to return to their normal anatomic location.

The groins are closed in layers with 2-0 Vicryl™Plus Antibacterial suture to reapproximate the femoral sheath, 3-0 Vicryl™Plus Antibacterial suture to reapproximate the lymphatics and deep tissues. A 4-0 Monocryl™ Plus Antibacterial suture is used in a subcuticular fashion to reapproximate the skin, and a topical skin adhesive such as DERMABOND PRINEO™ Skin Closure System, or any appropriate dressing

Potential complications include but are not limited to: