Patient safety, resident well-being and continuity of care with different resident duty schedules in the intensive care unit: a randomized trial

Background: Shorter resident duty periods are increasingly mandated to improve patient safety and physician well-being. However, increases in continuity-related errors may counteract the purported benefits of reducing fatigue. We evaluated the effects of 3 resident schedules in the intensive care unit (ICU) on patient safety, resident well-being and continuity of care.

Methods: Residents in 2 university-affiliated ICUs were randomly assigned (in 2-month rotation-blocks from January to June 2009) to in-house overnight schedules of 24, 16 or 12 hours. The primary patient outcome was adverse events. The primary resident outcome was sleepiness, measured by the 7-point Stanford Sleepiness Scale. Secondary outcomes were patient deaths, preventable adverse events, and residents’ physical symptoms and burnout. Continuity of care and perceptions of ICU staff were also assessed.

Results: We evaluated 47 (96%) of 49 residents, all 971 admissions, 5894 patient-days and 452 staff surveys. We found no effect of schedule (24-, 16- or 12-h shifts) on adverse events (81.3, 76.3 and 78.2 events per 1000 patient-days, respectively; p = 0.7) or on residents’ sleepiness in the daytime (mean rating 2.33, 2.61 and 2.30, respectively; p = 0.3) or at night (mean rating 3.06, 2.73 and 2.42, respectively; p = 0.2). Seven of 8 preventable adverse events occurred with the 12-hour schedule (p = 0.1). Mortality rates were similar for the 3 schedules. Residents’ somatic symptoms were more severe and more frequent with the 24-hour schedule (p = 0.04); however, burnout was similar across the groups. ICU staff rated residents’ knowledge and decision-making worst with the 16-hour schedule.

Interpretation: Our findings do not support the purported advantages of shorter duty schedules. They also highlight the trade-offs between residents’ symptoms and multiple secondary measures of patient safety. Further delineation of this emerging signal is required before widespread system change. Trial registration: ClinicalTrials.gov, no. NCT00679809.