Laboratory and clinical development of single keyhole umbilical nephrectomy

To describe our initial experience with single keyhole nephrectomy in a porcine model and in human subjects.

Eight nonsurvival laparoscopic nephrectomies were performed in 4 female farm pigs. In 3 renal units, the laparoscopic nephrectomy was performed via a novel single 25-mm trocar, while the remaining 5 nephrectomies were performed using one 10-mm and two 5-mm adjacent trocars. Articulating laparoscopic graspers, conventional endoshears, clips, and a stapler were used for dissection. Three human subjects underwent a single keyhole umbilical laparoscopic nephrectomy with similar instrumentation. Indications for nephrectomy included chronic infection in a nonfunctioning kidney in 2 patients, and a 4.5-cm enhancing renal mass in the other patient.

Single keyhole nephrectomy was successfully completed in all 8 porcine renal units and in all 3 human subjects. The mean operative time for the porcine nephrectomies was 49 minutes (range, 20 to 85), with a mean blood loss of 20 mL (range, 5 to 100). Incision size ranged from 3 to 5 cm. The mean operative time for the human nephrectomy cases was 133 minutes (range, 90 to 160). Estimated blood loss was 30 mL, and the kidneys were extracted through a solitary 2 to 4.5 cm periumbilical incision. There were no perioperative complications, and all 3 patients were discharged on hospital day 2.

Keyhole umbilical nephrectomy utilizing articulating laparoscopic instrumentation to facilitate triangulation is feasible. We demonstrate safe and successful completion both in a porcine model and in the 3 human patients. Future studies will need to assess the benefits of single-access surgery in comparison to conventional laparoscopy.