Efficiency of manual versus robotical (Zeus) assisted laparoscopic surgery in the performance of standardized tasks.

Background: The objective of this study was to compare the efficiency of manual and robotically assisted laparoscopic surgery.

Methods: To evaluate the surgical efficiency in a set of basic endoscopic movements, 20 medical students without any surgical experience were selected to perform at random a set of laparoscopic tasks either manually or robotic assisted (Zeus). This task consisted of dropping beads into receptacles, running a 25-cm rope, capping a hypodermic needle, suturing, and performing a laparoscopic cholecystectomy on a cadaver liver of a pig. A quantitative time-action analysis was performed to evaluate the efficacy and skill performance in terms of time and the number of actions.

Results: The dropping beads exercise and the laparoscopic cholecystectomy required more time when performed with robotic assistance, as compared with manual performance (respectively, median, 78.5 s; range, 63 - 122 s vs median, 144.5 s; range, 100 - 169 s; p <0.01 and median, 34.0 min; range 11-44 min vs median, 46.5 s; range, 21 - 79 min; p = 0.05). A tendency toward fewer total actions in all the robotically assisted exercises was observed. However, significance was shown only in the rope-passing task (median, 71; range, 59 - 87 vs median, 62; range, 57-80; p = 0.05). Grasping the beads, the rope, and either the needle or the cap were tasks that required fewer actions to complete when performed with robotically assistance (respectively, median, 11; range, 10 - 14 vs median, 12.5; range, 11 - 15; p <0.01; median, 56; range, 55 - 60 vs median, 60.5 min; range, 55 - 65; p = 0.03, and median, 6; range, 4 - 21 vs median, 10.5; range, 6 - 38; p = 0.02). As compared with the robotically assisted rope-passing exercise, more failures were made in the manually performed procedure (p = 0.03), mainly caused by unintentional dropping of the rope (p = 0.02).

Conclusions: Robotically assisted laparoscopic surgery by participants without any surgical experience might require more time, but actions can be performed equally or more precisely as compared with manual laparoscopic surgery.