[Laparoscopic transperitoneal replacement of the abdominal aorta with left renal artery reimplantation: experimental study on pigs].

OBJECTIVE

To study the feasibility and the tolerance of a combined laparoscopic transperitoneal aortic and renal restoration performed on animals.

METHODS

Six pigs (mean weight: 79.5 kg, range 73-86) underwent laparoscopic replacement of the abdominal aorta using a 6-mm Dacron(R) graft, with direct reimplantation of the left renal artery. The study protocol was approved by the Advisory committee of Animal Ethics. The animal was placed supine on the operative table with a pillow under the lumbar region in order to raise the aortic area. A first midline, 10-mm diameter trocar was placed under direct vision, 5 cm above the pubis and allowed the insufflation of a 12-mm Hg pneumoperitoneum. One 30 degrees optic was used during the intervention. The pig was then tilted to a 30 degrees Trendelenbourg's position and two other 10-mm trocars were introduced 5 cm medially to the right and left antero-superior iliac spines ). Four other 10-mm incisions were necessary for introduction of an intestinal retractor, a suction-irrigation device and two laparoscopic aortic clamps.

RESULTS

The procedure was performed in all animals in a mean operative time of 320 min (292-366), including ): - a time for aortic and renal artery dissection of 104 min (90-120), - a supra-renal aortic clamping time of 221 min (180-276), - a time for confection of proximal and distal aorto-prosthetic anastomosis of respectively 59 min (40-75) and 64 min (50-80), - a time for the left renal artery reimplantation of 72 min (40-140). Average blood loss was 525 ml (250-1050), and the mean pre and postoperative hemoglobin and pH values were 9.9 g/dl (8.9-10.7) versus 9.4 g/dl (8.5-11.3) and 7.36 (7.31-7.38) versus 7.30 (7.21-7.43) respectively. An angiogram ) performed before the sacrifice of animals showed a wide patent anastomosis in 18 (56%) cases, a<50% stenosis in 4 cases (22%), a > 50% stenosis in 1 case (5%) and a thrombosis of the first three renal artery restorations (17%) probably due to insufficient intraoperative heparinization.

CONCLUSION

This experimental study shows the feasibility of laparoscopic transperitoneal abdominal aortic restoration with re-implantation of the left renal artery (fig. et ). The techniques of arterial sutures must be improved in order to decrease aortic and renal clamping times.