Occupational Safety & Sleep: Medical Interns and Residents
Medical Interns
Recent research demonstrates that implementing protected sleep periods and addressing extended work schedules in healthcare settings can significantly improve both provider well-being and patient safety outcomes. Multiple randomized controlled trials involving medical interns and residents have shown that protected sleep periods of 3-5 hours during overnight shifts consistently increase sleep duration by approximately one hour compared to standard schedules, reduce the likelihood of nights with no sleep from 14-19% to 6%, and improve next-day alertness as measured by standardized sleepiness scales and psychomotor vigilance testing.
While these interventions show modest effects on measures of burnout, depression, and empathy, the objective sleep benefits are substantial, with interns typically obtaining only 2.2 hours of sleep during extended 30-hour shifts and experiencing chronic sleep restriction that persists even with post-call napping. The importance of addressing healthcare worker fatigue extends beyond physicians to nursing staff, where studies reveal that 40% of nursing shifts exceed 12 hours and the risk of medical errors increases significantly when nurses work extended shifts, overtime, or more than 40 hours per week. Collectively, this research supports the implementation of fatigue mitigation strategies in healthcare settings, including protected sleep periods for trainees and careful management of work hour limits, as essential components of patient safety and healthcare worker sustainability initiatives.
In this randomized controlled trial conducted at the Philadelphia VA Medical Center medical service and Oncology Unit of the Hospital of the University of Pennsylvania, we evaluated the feasibility and consequences of protected sleep periods during extended duty from 2009-2010. 103 interns and senior medical students were randomly assigned to either a standard intern schedule (extended duty overnight shifts of up to 30 hours; equivalent to 1200 overnight intern shifts at each site), or a protected sleep period (protected time from 12:30 AM to 5:30 AM with handover of work cell phone; equivalent to 1200 overnight intern shifts at each site). Results suggest that implementation of a protected sleep period while on call resulted in an increase in overnight sleep duration and improved alertness the next morning.
Read more here: Effect of a protected sleep period on hours slept during extended overnight in-hospital duty hours among medical interns: a randomized trial (2012)
In this randomized controlled study investigating in-hospital nighttime intensivist staffing, 20 faculty and 13 fellows assigned to rotations in the Medical Intensive Care Unit (MICU) of a tertiary care academic medical center were underwent a rotation with a standard staffing model, with in-hospital residents, with a fellow and faculty member available at nighttime by phone, and the intervention, with in-hospital residents with an in-hospital nighttime intensivist.
Although no differences were measured in patient outcomes between the two staffing models, in-hospital nighttime intensivist staffing was associated with small increases in total sleep duration for faculty and fellows, reductions in total work hours for fellows only, and improvements in subjective well-being for both groups. Staffing models should consider how work duration, sleep, and well-being may impact burnout and sustainability.
Read more here: Sleep and Work in ICU Physicians During a Randomized Trial of Nighttime Intensivist Staffing (2019)
Protected sleep periods for internal medicine interns have previously resulted in increased amount slept and improved cognitive alertness but required supplemental personnel. Here, we evaluated intern and patient outcomes associated with protected nocturnal nap periods of three hours that are personnel-neutral. In this randomized trial at Philadelphia Veterans Affairs Medical Center (PVAMC) Medical Service and Hospital of the University of Pennsylvania (HUP) Oncology Unit between 2010-2011, four-week blocks were randomly assigned to a standard intern schedule (extended duty overnight shifts of up to 30 hours), or sequential protected sleep periods (either an early or late nap period). HUP interns had significantly longer sleep durations during both early and late protected periods compared with controls, while at PVAMC, sleep duration was longer only for the late shift group. Interns assigned to either protected period were significantly less likely to have call nights with no sleep and had fewer attentional lapses on the Psychomotor Vigilance Test. Protected sleep periods of three hours resulted in more sleep during call and reductions in periods of prolonged wakefulness, providing a plausible alternative to 16-hour shifts.
Read more here: A randomized trial of a 3-hour protected nap period in a medicine training program: Sleep, alertness and patient outcomes (2014)
Fatigue from sleep loss is a risk to physician and patient safety, but objective data on physician sleep and alertness on different duty hour schedules is scarce. This study objectively quantified differences in sleep duration and alertness between 137 medical interns working extended overnight shifts and 87 PGY-2/3 residents not or rarely working extended overnight shifts. We found that interns averaged 6.93 hours of sleep per 24 hours across shifts- significantly less than residents not working overnight shifts- and they averaged 2.19 hours of sleep during on-call nights. Alertness was significantly lower on mornings after on-call nights compared to regular shifts, and sleep inertia significantly affected alertness in the 60 minutes after waking on-call. Extended overnight shifts increase the likelihood of chronic sleep restriction in interns.
Read more here: Sleep and alertness in medical interns and residents: an observational study on the role of extended shifts (2017)
We examined whether interns scheduled for a protected sleep period during overnight call would have better end-of-rotation assessments of burnout, depression, and empathy scores compared with interns without protected sleep periods and whether the amount of sleep obtained during on call predicted end-of-rotation assessments. A protected sleep period produced few consistent improvements in depression, burnout, or empathy, although depression was already low at baseline. Possibly the amount of protected time was too small to affect these emotional states or sleep may not be directly related to these scores.
The use of extended work shifts and overtime has escalated as hospitals cope with a shortage of registered nurses (RNs). Little is known, however, about the prevalence of these extended work periods and their effects on patient safety. Logbooks completed by 393 hospital staff nurses revealed that participants usually worked longer than scheduled and that approximately 40 percent of the 5,317 work shifts they logged exceeded twelve hours. The risks of making an error were significantly increased when work shifts were longer than twelve hours, when nurses worked overtime, or when they worked more than forty hours per week
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This national cluster-randomized trial compared sleep, sleepiness, and alertness among 398 medical interns at programs following either standard 2011 duty-hour policies (16-hour shift limits) or flexible policies (no shift length restrictions, but maintaining 80-hour workweeks). Data collected over 14 days using actigraphy, sleepiness scales, and alertness testing showed that sleep duration in flexible programs (6.85 hours per 24 hours) was noninferior to standard programs (7.03 hours)—a difference of only 10 minutes. Subjective sleepiness was also noninferior between groups. However, noninferiority was not established for objective alertness measured by the Psychomotor Vigilance Test. Interns in flexible programs compensated for sleep lost during extended overnight shifts by sleeping longer before day shifts, before extended shifts, and on days off.
Extended overnight shifts produced the worst outcomes across both groups. During these shifts, interns averaged only 5.12 hours of sleep, showed significantly reduced alertness (7.8 performance lapses), reported high sleepiness scores (6.8 on a 9-point scale), and 87.7% experienced excessive sleepiness, particularly between midnight and 6 AM. Despite near-recommended average sleep duration across the 14-day period, both groups reported excessive sleepiness on over 50% of trial days. The findings confirm that extended overnight shifts significantly impair sleep and alertness, highlighting the need for fatigue management strategies such as protected nap periods during overnight shifts in residency training programs.
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