The graveyard shift: experience with a night float system.

The aim of this study is to describe the effects of a new night float system on the circadian rhythm and clinical judgment of our residents. In addition, the study looks at the residents' opinions of how to optimize the night float system in the future. All 20 of the radiology residents at our institution completed a questionnaire about the night float system after completing their night float coverage. The results of the questionnaire were then compiled and tabulated. It took our residents an average of 2.0 days to become acclimated to the night float and an average of 2.3 days to return to a normal daily routine after completing the night float. No residents perceived impairment in their clinical judgment while on the night float. However, 9 of the 20 residents (45%) stated that their clinical judgment was improved on the night float compared to that of a 24-hour call. Eighteen of 20 residents (90%) preferred the night float system to a 24-hour call system. On average, our residents believe that the optimal number of hours for a night float shift is 10.5 hours and the optimal numbers of days to do the night float consecutively is 6.8 days. In conclusion, a night float system can be a preferable means of evening coverage as it has a minimal effect on the circadian rhythm by allowing residents to become acclimated to working the night shift over the course of several days. The night float system also demonstrates no appreciable adverse effects on clinical judgment and may allow better clinical judgment than a 24-hour call system.