[Laparoscopic partial nephrectomy: urology resident learning curve on a porcine model].

Introduction: Several teams have recently confirmed the technical feasibility of laparoscopic partial nephrectomy (LPN). However, this procedure is not widely performed because it is technically difficult and associated with a high rate of bleeding complications, even for experienced teams. The authors studied the LPN learning curve for urology residents using a porcine model based on analysis of the following criteria: operating time, warm ischaemia time and intraoperative and postoperative bleeding.
Materials and Methods: Forty LPN were performed by the same operator. All operations were performed after arterial clamping and heparinisation of the animal. The renal section was always the same, removing 40% of the kidney and always comprised the excretory tract. A continuous running suture on the excretory tract and interrupted sutures on the parenchyma were performed. Operating time and warm ischaemia time were recorded. Animals were monitored for ten days. Intraoperative and postoperative bleeding via drains was recorded and retrograde urography was performed on the 10th day to confirm the absence of excretory tract leaks. Linear regression statistical tests investigated a correlation between these various criteria and the number of cases performed.
Results: The mean total operating time, warm ischaemia time and total bleeding (intraoperative and postoperative) were 108 minutes (70-140 minutes), 38 minutes (22-50 minutes) and 95 ml (10-300 ml), respectively. Linear regression analysis revealed a direct correlation between the number of cases performed and intraoperative bleeding (p<0.001) and warm ischaemia time (p<0.001). These parameters became stable after the 10th operated case. Two cases of urine leaks were observed on D10 out of a series of 40 operations, with no correlation with the number of cases performed.
Conclusion: The operating time and warm ischaemia time are directly correlated with the number of cases performed. Training on a porcine model appears to be a good way to reduce the learning curve in man. Ten operations are necessary to acquire the various steps of the procedure.