Fatigue in surgical residents an analysis of duty-hours and the effect of hypothetical naps on predicted performance.

PURPOSE: Sleep loss and fatigue, common in resident physicians, are related to increased medical errors and decreased physician wellbeing. Biomathematical modeling of fatigue can illuminate the relationship between surgical resident fatigue and work scheduling. METHODS: General surgery resident schedules were analyzed using the Sleep, Activity, Fatigue and Task Effectiveness model to predict resident performance during work hours. Hypothetical naps were built into the model to assess their effect on predicted performance and fatigue risk. RESULTS: 12 months of duty-hours logged by 89 residents, ranging from post-graduate year (PGY) 1-5, were analyzed. Residents had moderate levels of fatigue risk over 12 month schedules, with at least an 8-h sleep debt during 24.36% of shifts. Performance scores decreased as shift lengths increased. The addition of hypothetical naps increased predicted performance and reduced shift time with fatigue risk. CONCLUSIONS: Biomathematical modeling of resident schedules and predicts a concerning level of fatigue and decreased effectiveness. Naps may improve performance without decreasing scheduled hours.