Waterjet Dissection for Partial Nephrectomy Without Hilar Clamping in a Porcine Model

Hilar clamping is typically used in partial nephrectomy to control hemorrhage, which may damage the renal tissue under warm ischemia conditions. The purpose of this study was to evaluate waterjet technology in partial nephrectomy without renal hilar vascular control in a porcine model. Bilateral partial nephrectomy using waterjet was performed in 8 pigs (16 kidneys: 8 for wedge resections, 8 for pole resections). The operations were performed successfully in all animals. The mean dissection time was 30.6 ± 2.9 minutes for pole resections and 36.5 ± 3.5 minutes for wedge resections. The mean blood loss was 51.6 ± 11.7 mL for pole resections and 38.7 ± 9.2 mL for wedge resections. The novel waterjet technique provided precise and effective hydrodissection of the kidney, avoiding damage to the vascular structures or collecting system.Key words: Partial nephrectomy, Waterjet dissection, Animal experimentKidney cancer is one of the most common cancers in the urinary system. More and more asymptomatic small renal tumors are diagnosed because of the wide use of imaging technologies.¹ For decades, radical nephrectomy was considered the gold standard treatment for localized renal cancer. In recent years, nephron-sparing procedures (partial nephrectomy) have been demonstrated to have similar outcomes to traditional radical nephrectomy for small renal tumors.² However, partial nephrectomy is a challenging operation with a high risk of parenchymal bleeding and damage to the collecting system. Renal hilar vessel clamping is still the first choice to minimize the parenchymal bleeding. Partial nephrectomy is then completed expeditiously under warm ischemia with limited time constraints.³ However, temporary warm ischemia may lead to renal function deterioration, especially for solitary kidneys. It is imperative to improve the surgical technique of partial nephrectomy without relying on renal hilar clamping.Waterjet dissection has been used for selective dissection of the parenchyma of liver,^4–6 pancreatic necrosectomy,⁷ and endoscopic submucosal dissection for gastrointestinal tumors.^8–10 In this study, we investigated whether waterjet resection is applicable or feasible for partial nephrectomy without temporary ischemia in a porcine model.