Cutting errors in surgery: experience limits underestimation bias in a simulated surgical environment

Objective: Error management is crucial in surgery and needs to be developed through appropriate training and education. Research suggests that perceptual errors may be more likely in laparoscopic environments. The objective of this work is to investigate error management by novices compared with experienced surgeons when performing a simple simulated incision in a visually challenging environment.

Methods: Novices (n = 20) and experienced surgeons (n = 11) viewed pairs of horizontal lines on a laparoscopic monitor. Participants were asked to replicate the line lengths by making simulated incisions. The task was completed with or without online visual feedback of the incising hand. In a second phase of the study, the task was complicated by embedding the lines within a perceptual illusion (i.e., Ponzo illusion).

Results: Incision lengths generally were shorter than the actual lengths of the viewed lines for all participants. For the novices, however, this underestimation bias was exacerbated when visual feedback of the incising hand was unavailable (p < 0.001), whereas the surgeons were not affected by loss of vision of the incising hand (p = 0.864). Furthermore, novices were influenced by the perceptual illusion designed to alter perceptions of line length (p = 0.021), whereas the surgeons did not appear to be influenced by the illusion (p = 0.945).

Conclusions: A perceptual bias towards incision length underestimation may be present when surgery involves a laparoscopic monitor; however, surgical experience may protect against accentuation of the underestimation bias when the task becomes more visually challenging. The bias is discussed using the framework of error management theory.