Laparoscopic partial nephrectomy in the pig: Comparison of three hemostasis techniques

Background and Purpose: Control of intraoperative bleeding is the main tech nical difficulty encountered during laparoscopic partial nephrectomy, The o bjective of this study was to compare the efficacy and morbidity of three r enal parenchymal hemostasis techniques: high-frequency bipolar electrical c urrent, high-frequency unipolar spray electrical current, and ultrasound du ring laparoscopic partial nephrectomy performed in pigs without vascular co ntrol. Materials and Methods: A standardized laparoscopic transperitoneal right lo wer-pole partial nephrectomy was performed in 27 pigs with a mean weight of 65 +/- 5 kg, The pigs were divided into three groups according to the tech nology used: Group 1 = bipolar electrical current, Group 2 = unipolar spray electrical current, and Group 3 = ultrasound. Intravenous urography was pe rformed on the 28th day, The kidneys were then removed for histologic exami nation, and the pigs were sacrificed. The criteria evaluated were intraoper ative and postoperative complications, blood loss, renal function, and thic kness of the parenchymal lesions induced. The Kruskal-Wallis nonparametric test for comparison of medians was used for statistical analysis of the dat a (P < 0.05), Data from pigs that died before the end of the study were exc luded from the analysis. Results: All partial nephrectomies were performed laparoscopically, and all pigs were alive at the end of the operation. The postoperative complicatio n rate was 11% (N = 3): two pigs died before the end of the study, one from hemorrhage on Day 6 (Group 2), and the other from prolonged reflex ileus w ith sacrifice of the pig on Day 7 (Group 3), One pig developed an asymptoma tic urinoma (Group 2), Blood loss was significantly lower when ultrasound w as used (P = 0.026), Global renal function was not significantly altered in the various groups. The median thickness of tissue necrosis and fibrosis d etected in the scar zone was 6 mm (range 4-10 mm) and was similar in the th ree groups. Conclusion: Partial nephrectomy can be performed by laparoscopy without vas cular control in the pig. Coagulation by ultrasound appears to present an a dvantage in terms of limitation of blood loss compared with coagulation by bipolar or unipolar spray electrical currents without presenting any benefi t in terms of preservation of the renal parenchyma.