The cognitive impact of guard shifts in physicians: a before-after study

We intend to evaluate the change of different cognitive functions after a guard shift in physicians.

A descriptive observational study was performed. The study population included Spanish physicians who were asked to complete before and immediately after their guard shift the following tests: Digit Span, TMT-A, TMT-B, Symbol Digit, Stroop, Free and Cued Selective Reminding, creep and formal fluency, Visual Orientation and Space Perception tests, and the Leeds Sleep Questionnaire.

Thirty subjects were included in the study among which 43.3% were female. The mean subjective impression of the guard shift was 4.47/10 (2.57) and was correlated with the number of sleep hours during the guard shift (r = 0.72, p < 0.001). Statistically significant differences in the comparison between pre- and post-guard period results were found for the Symbol Digit test (88.27 vs. 81.47, p = 0.005), Digit Span test (7.43 vs. 7.00, p = 0.025), Free and Cued Selective Reminding Test (22.73 vs. 21.20, p = 0.002), categorical fluency (39.03 vs. 34.53, p = 0.008), and phonemic fluency (19.57 vs. 16.13, p = 0.001).

The realization of guard shift was associated with a lower yield in several cognitive functions, especially in tasks related to executive function and attention.