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Page 12 of 17 Hong et al. Vessel Plus 2022;6:4 https://dx.doi.org/10.20517/2574-1209.2021.88

Distal anastomosis
When a four-branched replacement graft is used, the distal anastomosis is performed before reattachment
of the visceral and renal arteries to re-establish flow to the lower extremities while the visceral and renal
organs continue to be perfused via the LHB and renal cooling circuit, respectively [Figure 10]. The distal
aortic anastomosis is usually sewn at the level of the aortic bifurcation but can be anastomosed to the iliac or
femoral arteries, using additional grafts as needed. If the chronic dissection extends distally, the septum is
fenestrated to ensure downstream perfusion into both lumens. The aortic graft is cut to a suitable length to
prevent kinking or tension, and a 3-0 polypropylene suture is used in a continuous fashion to complete the
anastomosis. As before, felt-pledgeted mattress sutures are used to reinforce the anastomosis.

The patient is then placed in the Trendelenburg position, and a 19-gauge needle is used to create deairing
holes in the Dacron graft. Individual clamps are placed on each of the four branches of the prefabricated
graft. The aorta is deaired through one of the branches of the graft. The aortic cross-clamp is slowly
removed to reestablish blood flow to the lower body. Anesthesia facilitates patient resuscitation to maintain
MAP after cross-clamp removal; typically, the use of bicarbonate and vasopressors is necessary.

Visceral and renal anastomosis with a four-branched graft
The ostia of the celiac, SMA, and renal arteries are isolated on buttons of aortic tissue and are carefully
inspected for extension of dissection as well as for calcium or stenosis related to the atherosclerotic process.
Endarterectomy, decalcification, or direct stenting (usually with a 7-mm × 15-mm balloon-expandable
stent) may be required. If the dissection extends into the visceral arteries, fenestration may be necessary to
ensure the perfusion of both lumens. The perfusion catheters are maintained to limit ischemic time. Because
the right renal artery is most posterior, it is sewn first; we use a 4-0 or 5-0 polypropylene suture [Figure 11].
The anastomosis is deaired, and the clamp is released to reestablish perfusion. Then, the SMA and celiac
axis anastomoses are carried out. We typically leave the SMA clamped during the celiac axis anastomosis to
prevent back-bleeding through collateral arteries, which affects visualization. The left renal artery
anastomosis is typically sewn last. The inferior mesenteric artery is usually oversewn, but reimplantation
may be necessary if bilateral hypogastric artery occlusions, previous colectomy, or a diseased SMA are
present.

Hemostasis and closure
In preparation for closure, the four-branched graft is inspected for malorientation, kinks, or twists. The
femoral arteries, renal arteries, celiac axis, and SMA [Figure 12] are palpated for a distal pulse, and the
kidneys are palpated for turgor. The bowel is visualized to confirm its perfusion. The spleen is inspected for
any hematoma or laceration; any splenic injury that cannot be controlled with electrocautery or packing
necessitates a splenectomy to avoid potential bleeding complications. The patient’s temperature is passively
rewarmed to > 34.5 °C. We confirm the position of the nasogastric tube before closure. An abdominal drain
is placed in the retroperitoneal space. The left hemidiaphragm is reapproximated under tension by using a
#1 polypropylene continuous suture that is locked every three bites. Two chest tubes are placed,
anterosuperiorly and posteroinferiorly. Absorbable pericostal sutures are placed in and around the ribs in a
figure-of-eight, interrupted fashion with #2 coated braided polyester sutures. Two #7 steel wires are placed
to secure the thoracotomy closure. The abdominal fascia is closed and tied to the diaphragmatic suture. Soft
tissue is closed, and single-lung ventilation is discontinued.

Postoperative care
Critical care monitoring and volume resuscitation form the cornerstone of postoperative care in patients
with a TAAA. The MAP is maintained at 80-100 mmHg, and the patient’s neurological status is checked
every hour, particularly the patient’s leg strength. The patient’s hemoglobin level is kept above 10 g/dL to