Tensile force exerted by suture during renorrhaphy using current techniques

Partial nephrectomy has become the preferred treatment option for small renal masses. In particular, minimally invasive partial nephrectomy (MIPN) using laparoscopic or robotic approaches has shown decreased blood loss, shorter hospital stay, and faster return to normal activity compared to open surgery. However, MIPN still carries risk of postoperative complications including hemorrhage and urine leakage. Closure of the renal remnant, often called renorrhaphy, is a critical step to avoid these complications. The purpose of the study was to provide quantitative data on suture properties during partial nephrectomy. Multiple suture techniques have been proposed for renal closure during robotic-assisted partial nephrectomy. There is no consensus for preferred closure technique and this decision is at the discretion of the surgeon. Simulated partial nephrectomies were performed on porcine kidneys. Renorrhaphy was completed with barbed suture using a simple running, interrupted sliding-clip, or horizontal mattress technique. Suture tension was obtained prior to tissue failure with force sensors measuring in newtons (N). The interrupted sliding-clip and horizontal mattress techniques performed similarly with median force values of 11.06 N and 12.20 N, respectively. The simple running technique performed with a median force of 3.62 N. ANOVA proved statistical significance. Interrupted sliding-clip and horizontal mattress sutures exert similar forces prior to tissue failure during renorrhaphy. Both techniques were able to achieve forces great enough to overcome the hydrostatic pressure of perfused renal tissue. Simple running sutures failed at significantly lower forces. When closing renal defects after partial nephrectomy, sliding-clip and horizontal mattress should be utilized over simple running sutures.