Circadian Profile of an Emergency Medicine Department: Scheduling Practices and Their Effects on Sleep and Performance

J Emerg Med. 2020 Jan;58(1):130-140. doi: 10.1016/j.jemermed.2019.10.007. Epub 2019 Nov 22.


Background: Shiftwork causes circadian disruption and is the primary reason for attrition from Emergency Medicine.

Objectives: We aimed to develop concrete recommendations to mitigate negative effects of shiftwork based on measures of work, sleep, alertness, and performance in emergency physicians.

Methods: Thirty-one Emergency Medicine residents were surveyed retrospectively about sleep and alertness on different shifts. Additionally, the sleep, performance, and alertness of 22 Emergency Medicine resident and attending physicians was tracked continuously over 4 weeks via sleep logs, actigraphy, real-time reported sleepiness, and performance on a vigilance task. Schedules were analyzed for circadian disruption. Physicians also predicted their sleep schedules, which were compared with actual schedules; participants tracked extensions of shifts, schedule changes, and shifts in other hospitals.

Results: Daily rhythms were apparent in real-time performance and alertness data, with peaks at around 4 pm. Sleep difficulty was highest, sleep shortest, and alertness and performance lowest for night shifts. Emergency Medicine residents tended to cluster multiple night shifts in a row, despite evidence of accumulating sleep debt over consecutive shifts. There were many shifts that caused high circadian disruption, which could be avoided by simple amendments to scheduling practices.

Conclusions: Circadian principles should be applied as suggested by the American College of Emergency Physicians. Chronotype should be considered in scheduling. Night shifts, particularly, should not be extended. Clustering all night shifts in a row should probably be discouraged. The additional vulnerabilities for night shift could be mitigated by adopting napping mid- or post night shift and by providing pay differentials.

Keywords: alertness; circadian; performance; shiftwork; sleep.