Trial Information

The Use of Self Retaining Sutures in Open and Laparoscopic Partial Nephrectomy

With the increased use of radiographic imaging for abdominal complaints the incidental
finding of small asymptomatic renal masses has increased. Partial nephrectomy has become the
gold standard therapy for treatment of kidney masses ≤7cm in size. Absolute indications for
partial nephrectomy include bilateral renal tumors, systemic condition affecting renal
function, chronic renal insufficiency and solitary kidney function. Elective indications
include masses ≤7cm and normal contralateral kidney function. The procedure can be completed
through either laparoscopic or open technique. Complication rates from open and partial
nephrectomy have been reported to be about 16% with the most common being urinary leak,
postoperative bleeding, renal insufficiency and the need for dialysis.

A major predictor of postoperative complications is the warm ischemia time. This is the
length of time the kidney is without blood flow at body temperature. It has been reported
that renal and cellular damage of the nephron begins after 20-30 minutes of ischemia. As
well, the volume of estimated blood loss has been shown to be a major predictor of
postoperative complications. A threshold value of estimated blood loss >750 mL and warm
ischemia time >45 minutes have been associated with significantly increased rates of
postoperative complications. Recent advancements in laparoscopic technique have lead to the
development of the early unclamping method of partial nephrectomy. In this method the renal
pedicle is unclamped following the initial central running suture but before the defect has
been entirely repaired with bolstering sutures. This method has been reported to decrease
warm ischemia time by ≥50% in comparison to the traditional technique of unclamping after
full closure of the defect.

The investigators have demonstrated the safety of the "Quill" (Angiotech, Vancouver, BC)
polydioxanone barbed self retaining sutures in a retrospective series. These sutures contain
unidirectionally oriented barbs on the surface that switch direction at the half-way point.
Laparoscopic partial nephrectomy is a technically demanding procedure and maintaining
tension during intracorporeal suturing is particularly challenging. The barbs of the self
retaining sutures lock into the tissue allowing the surgeon to preserve tissue approximation
without needing to maintain tension. The investigators believe these sutures will allow the
surgeon to obtain greater tissue approximation therefore decreasing postoperative urinary
leakage and bleeding. These findings need to be validated postoperatively.

The investigators believe that coupling the shorter warm ischemia time of the early
unclamping method and the greater tissue approximation afforded by the self retaining
sutures will result in fewer complications following partial nephrectomy.