Effect of postcall fatigue on surgical skills measured by a robotic simulator

Purpose: To examine the effect of a 24-hour call on residents' performance of a suturing task using the objective results calculated by the da Vinci Skills Simulator (Intuitive Surgical, Sunnyvale, CA). Subjects and Methods: Residents from urology and general surgery completed a single suturing skill immediately before and after a 24-hour call. Residents completed the task at least twice and were scored on three measures: time to complete the exercise, time to load the needle, and time to tie the knot. These scores were correlated with previous simulator experience, trainee level, and level of postcall fatigue. Results: Thirteen residents (four senior and nine junior) participated; six had no simulator experience. All time measures were significantly longer when residents were postcall (p<0.05). In the precall measures, previous robotic simulator experience was associated with improved time for completion of the exercise, needle loading, and knot tying (p<0.05). In the postcall measures, however, the difference in performance between residents with and without previous simulator experience was no longer statistically significant (p>0.05). When examining factors that predicted an increased task time on multivariate analysis, being postcall consistently increased the time to complete the exercises, while previous simulator experience and trainee level decreased the time to complete tasks. Conclusions: Previous studies have shown that postcall-related fatigue is associated with decreased surgical skills in the operative room. We demonstrate this effect by having residents test their skills, precall and postcall, using a novel easily reproducible technique. Time to complete the three measures analyzed was significantly increased following a 24-hour call for all participants. Fatigue acts as an equalizer of abilities in that the effects of fatigue nullify the benefits of having previous robotic simulator experience.