The impact of neurosurgical procedure on cognitive resources: Results of bypass training

BACKGROUND: Neurosurgeons are exposed to unavoidable distractions in their natural operating environment. Distractions can affect both the surgeon's concentration and the safety and duration of the surgery. Such distraction can be studied by applying a simultaneous cognitive task during a surgical procedure. METHODS: We used a previously described cognitive task: a forward (DF) and backward digit (DB) repetition task to interfere with the surgeon's attention during a training bypass. A pilot study was performed to find suitable digit repetition lengths. For the main experiment, we used four-digit strings. The test task was alternated across two consecutive sutures (n = 153, 8 bypasses), followed by two consecutive control sutures without digit repetition. The duration and the number of correct answers for the digit repetition task were compared to a baseline digit repetition without simultaneous surgery. RESULTS: During the bypass surgery, digit repetitions (especially DB) became slower (P < 0.0001). More errors were made during DB compared to DF only during simultaneous bypass (P < 0.0001). However, we found no effect of digit repetition tasks on individual suture times (P = 0.823). CONCLUSIONS: The ability to engage in simultaneous tasks while performing surgery is diminished. A surgeon with extensive training can withstand external distraction without an effect on performance; however, this is achieved by partially ignoring the simultaneous task. Our data support that during surgery other cognitive tasks should be avoided to ensure safety.