Sequence and task analysis of instrument use in common laparoscopic procedures

Background: In the area of instrument evaluation, one aspect that still requires objective assessment is the dynamics of instrument maneuver and exchange. If we could gain a better understanding of these phenomena, we could improve the design of the instruments themselves. Methods: A total of 29 laparoscopic procedures were videotaped and reviewed using time motion analysis. Instrument multifunctionality was determined using a standardized list of laparoscopic maneuvers. State transition diagrams were utilized to document the sequence of instrument exchanges. Results: The curved dissector, atraumatic grasper, and cautery scissors were identified as the most multifunctional instruments; each was able to perform five distinct maneuvers. Instrument sequences were found to consist of a three-part dissect → clip → cut cycle and a two-part dissect → suction cycle of instrument exchange. Conclusion: This study demonstrated that laparoscopic instruments are often used to perform a variety of maneuvers in addition to their primary function. Furthermore, there are common patterns in instrument exchange that provide a potential source of design parameters for improved surgical efficiency.