Sleepiness may affect surgeons' ability to deal with the unexpected.

Sleep deprivation increases cognitive workload during simulated surgical tasks
Sleep-deprived surgeons can perform a previously learned task or learn a new task as well as surgeons who are rested, according to Penn State College of Medicine researchers. However, in sleep-deprived surgeons, the brain must work harder, which could lead to problems during unexpected events.

The researchers reached these conclusions using simulations to study the effects of sleepiness on surgeons.
"Particularly in surgery, simulation has become the introduction to many procedures for new residents," said Jonathan Tomasko, M.D., a research fellow involved in surgical resident training. "Coupled with an 80-hour work week restriction, simulation is becoming increasingly important to ensure an adequate level of skill prior to operation on a patient." Eureklert!
American Journal of Surgery
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