Rotating shiftwork schedules: can we enhance physician adaptation to night shifts?

To evaluate the effectiveness of a broad, literature-based night shiftwork intervention for enhancement of emergency physicians' (EPs') adaptation to night rotations.

A prospective, double-blind, active placebo-controlled study was conducted on 6 attending physicians in a university hospital ED. Three data sets were collected under the following conditions: baseline, after active placebo intervention, and after experimental intervention. In each condition, data were collected when the physicians worked both night and day shifts. Measurements included ambulatory polysomnographic recordings of the main sleep periods, objective performance tests administered several times during the subjects' shifts, and daily subjective ratings of the subjects' sleep, moods, and intervention use.

The subjects slept an average of 5 hr 42 min across all conditions. After night shifts, the subjects slept significantly less than they did after day shifts (5 hr 13 min vs 6 hr 20 min; p < 0.05). The physicians' vigilance reaction times and times for intubation of a mannequin were significantly slower during night shifts than they were during day shifts (p = 0.007 and p < 0.04, respectively), but performances on ECG analysis did not significantly differ between night and day shifts. Mood ratings were significantly more negative during night shifts than they were during day shifts (more sluggish p < 0.04, less motivated p < 0.03, and less clear thinking p < 0.04). The strategies in the experimental intervention were used 85% of the time according to logbook entries. The experimental and active placebo interventions did not significantly improve the physician's performance, or mood on the night shift, although the subjects slept more after both interventions.

Although the experimental intervention was successfully implemented, it failed to significantly improve attending physicians' sleep, performance, or mood on night shifts. A decrease in speed of intubation, vigilance reaction times, and subjective alertness was evident each time the physicians rotated through the night shift. These findings plus the limited sleep across all conditions and shifts suggest that circadian-mediated disruptions of waking neurobehavioral functions and sleep deprivation are problems in EPs.