Comparison of Laparoscopic Skills Performance Using Laparoscopic Single-Site Access (SSA) Devices vs. an Independent-Port SSA Approach

Matthew R Schill, BSE, J Esteban Varela, MD, Margaret M Frisella, RN, L. Michael Brunt, MD. Section of Minimally Invasive Surgery, Washington University School of Medicine, St. Louis, MO

Introduction: Interest in single site access (SSA) laparoscopy as an alternative to standard multi-port laparoscopy has led to the development of SSA–specific access devices. We analyzed and compared performance of validated laparoscopic tasks on four commercially available SSA access devices (AD) compared to an independent port (IP) SSA set-up.

Methods: A prospective, randomized study of laparoscopic skills performance on four AD-SSA set-ups (Applied Medical GelPOINT, Covidien SILS Port, Ethicon Endo-Surgery SSL Access System, ASC TriPort) and an IP-SSA set-up (three independent low profile ports placed via one access site) was conducted. Fourteen medical students (2nd-4th year), four surgical residents, and five attending surgeons were first trained to proficiency in multi-port laparoscopy using four laparoscopic drills (peg transfer, bean drop, pattern cutting, extracorporeal suturing) in a standard laparoscopic trainer box model. These four drills were then performed in random order on each IP-SSA and AD-SSA set-up using straight instruments. Repetitions were timed and number of errors recorded. Data are mean ± SD, and statistical analysis was by two-way ANOVA with Tukey HSD post-hoc tests.

Results: Level of training and port set-up used had statistically significant effects on total task time (see table; p < 0.001). Attending surgeons had significantly faster total task times than either residents or students (p < 0.001), but the difference between residents and students was not significant. Pair-wise comparisons between set-ups within each group revealed statistically significant differences in total task time between the IP-SSA set-up and each of the AD-SSA set-ups within the student group. Although times averaged over 100 seconds longer for the AD-SSA set-ups vs IP-SSA for residents and attending surgeons, the differences were NS. Overall, independent of level of training, the total task time was significantly less for the IP-SSA set-up than for each of the four AD-SSA set-ups (p < 0.001). Similarly, independent of level of training, the IP-SSA set-up was significantly faster than 3 of 4 AD-SSA set-ups for peg transfer, 3 of 4 AD-SSA set-ups for pattern cutting, and 2 of 4 AD-SSA set-ups for suturing (not shown). No statistically significant differences in error rates between IP-SSA and AD-SSA set-ups were detected.

Table. Total combined task time for the four drills (in seconds). *=p<0.05 compared with IP-SSA set-up (within groups).

Conclusions: When compared to an independent port single site laparoscopic set-up, single site laparoscopic access devices are associated with longer total laparoscopic task times in a trainer box model independent of level of training. Task performance was not significantly different across different SSA devices.