The Boatman's knot: a single knot for renal-vein ligation during laparoscopic nephrectomy: description of technique and evaluation of feasibility and safety

BACKGROUND AND PURPOSE: The endovascular stapler is the standard of care for renal-vein ligation during nephrectomy, but recently, some reports have addressed the need for lowering the costs in the operating room. The authors describe the first use of "boatman's knot" in renal-vein ligation during laparoscopic nephrectomy and tests of its safety and feasibility. MATERIALS AND METHODS: Sixteen bilateral laparoscopic nephrectomies were performed in female pigs. On the right side, the renal vein was ligated with the boatman's knot, and on the left side, the vein was ligated with conventional intracorporeal technique. The knots were performed by the same surgeon at initial laparoscopic training. The time required to tie the knots was measured. After bilateral nephrectomy, a midline incision was created, and the bursting pressure of the knots was measured with a manometer by saline infusion into the vena cava. RESULTS: The average knot-completion time was 45 seconds (range 30-50 seconds), and the average time needed to carry out the conventional suture was 202.5 seconds (range 186-228 seconds). After renal-vein transection, there was complete hemostasis in all cases. The mean bursting pressure was 179.9 mm Hg (range 126-304 mm Hg). In five cases, the rupture site was in a lumbar vein previously sutured, while in three cases, the rupture happened in the vena cava itself. CONCLUSION: The boatman's knot is feasible, safe, easy to learn, and faster than conventional intracorporeal suturing. This technique may replace the endovascular stapler. However, its clinical applicability remains to be determined.