Effect of the diameter of the endoscope and of surgeon training on the duration and quality of laparoscopic surgery in a rabbit model

Study Objective. To evaluate the effect of diameter of the endoscope on the duration and quality of laparoscopic surgery. Design. Prospective, randomized trial (Canadian Task Force classification I ). Setting. Centre for Surgical Technologies. Subjects. Sixty adult, female, New Zealand, white rabbits. Intervention. Two series of laparoscopic nephrectomies, one each performed by an experienced and an inexperienced surgeon comparing 10-, 5-, 4-, and 2 -mm endoscopes. Measurements and Main Results. Besides duration of surgery and occurrence o f bleeding, the quality of dissection was scored by adding scores of dissec tion of renal vessels, ureters, and kidneys. During consecutive nephrectomi es, the duration of surgery (p = 0.001) and occurrence of bleeding (p = 0.0 2) decreased, whereas the quality of dissection increased (p = 0.002), demo nstrating the learning curve, mainly for the less experienced surgeon. Dura tion of surgery (p = 0.04) decreased and quality of dissection increased (p = 0.05) when the larger endoscope was used. This was the case only for the less experienced surgeon, whereas for the experienced surgeon it had only a slight effect on learning curve. Conclusion. These results confirm a learning curve of nephrectomy consistin g of some 20 animals. In addition, the endoscope diameter and thus quality of image affect both duration and quality of surgery, especially for less e xperienced surgeons.