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Sleep, or Not to Sleep, Is that Still the Question?

S leep deprivation in medical practice is as old as medicine history and for a long time, working under the effect of sleep loss has been considered as “a badge of honor” and a symbol of professional commitment especially by the surgical community. Nevertheless, some evidence corroborates with the fact that sleep is a basic necessity and it is essential to well-being and a healthy condition. Human sleeping patterns are controlled by both homeostatic mechanisms that increase sleep necessity in response to time spent awake and a circadian body clock that promotes wakefulness and sleep according to usual times of activity and rest. Chronic disturbances of these tightly controlled systems have been associated with cardiovascular morbidity, metabolic diseases such as obesity and diabetes, and elevated cancer risk.1 Some professional activities are unavoidably related to overnight work or extended shifts, and certainly, doctors are the most emblematic example. The allowable numbers of continuous-duty hours for residents are often greater than those in commercial aviation, commercial driving, and the nuclear power industry.2 Moreover, physician trainees are probably exposed to a higher risk of stress and anxiety than seniors, because of the lack of experience dealing with ill or dying people and their lack of endurance. The apprehension about making a mistake or to harm a patient can generate psychological fatigue and negative impact on professional performance. Block et al reported burnout associated with on-call duties, heavy workload and fatigue in 76% of firstyear residents.3 Patient death related to resident fatigue and the high incidence of burnout have motivated an intense debate since the last decades and several studies concerning residents’ duty hours and sleep deprivation have been published with diverging results. From a patient perspective, some studies have focused on the relationship between physician’s fatigue and patient’s safety using clinical outcomes as fatigue-impaired performance markers. It is noteworthy that the weak point of those kind of studies is the fact that clinical or surgical complications are relatively low-frequency events, and their use as endpoints is a matter of question and probably a factor of underpowered results. The FIRST trial published by Bilimoria et al,4 evaluated a less restrictive duty-hour policy (duty hours exceeding 16 h for first-year residents and 28 h for more experienced ones and requiring shorter periods of hands-off between shifts) using patient mortality and severe complications as primary endpoints. The results showed non inferiority of what was called “Flexibility policy” but residents reported negative effect on time with family and friends, time for extracurricular activities, rest, and health. Furthermore, this kind of study raises some important ethical considerations.5,6 If we consider that doctors and patients are research subjects in the frame of an interventional study, then both of them must be informed and consent with study conditions. Would patients in a teaching hospital agree to be operated upon by a surgeon awake for >24 hours? On the other hand, from the doctor’s working safety perspective, an increasing number of studies have been published about the impact of working nights or odd shifts on central nervous system functioning or even the risk of fatigue-related motor vehicle crashes after work.7–9 In an original study comparing surgical residents after night shifts and alcohol intoxication, Huizinga et al10 showed that the performance of post-call surgeons was similar, or even worse than, the performance of intoxicated surgeons. In line with other authors, the work lead by Leu et Vuille-dit-Bille recently published in Surg Laparosc Percutan Tech concludes that 24-hour sleep deprivation does not negatively impact on laparoscopic performance of novice surgeons assessed by a computer simulator.11–13 But how reliable are simulators in reproducing the complexity of surgical practice, including making decisions, interacting with patients, patients’ family, and other medical and paramedical co-workers? How sensitive are they to detect complex cognitive impairments? Certainly, computer virtual reality models are useful tools in surgical training, and by now, it seems to be the best method to assess surgical outcomes without major ethical limitation. Nevertheless, we must be cautious about the extrapolation of those results and their applicability in real life. An interesting way to improve the quality of these studies is to associate neurophysiological tests in order to assess more specific fatigue-related disturbances than only manual skills. In another study using a laparoscopic simulator and enhanced by an EEG assessment, Kahol et al,14 quantified residents’ fatigue, showing that the impact of fatigue on performance is not evident when residents are charged to complete purely mechanical tasks, but its effect is clearly depicted in tasks that combine psychomotor and cognitive dimensions. There is little doubt that typical surgical abilities do not drastically deteriorate with a limited amount of sleep loss. Yet, if we take into account the lack of sensitive laboratory methods and the absence of a mechanistic account of the impact of sleep deprivation and fatigue on surgical performance, we have to admit that the interpretation of heterogenous and diverging results is a controversial issue, and caution must be taken to not promote the image of surgeons as physicians who can work flawlessly under the effect of sleep deprivation. Recently, the Accreditation Council for Graduate Medical Education (ACGME) revised common program requirements for residents in the United States and maintained an 80-hour per-week cap on residents’ work, averaged over 4 weeks, but extended the permissible work shifts for first-year residents from 16 to 24 hours. In European Countries working hours are generally limited to a 48-hour-week, with work shifts that range from 8 to 24 hours. These geographical variabilities can be explained by different political pressures, cultural aspects and differences in medical training funding and local The author declares no conflicts of interest. Reprints: Ailton Sepulveda, MSc, MD, 100, Boulevard du General Leclerc, Clichy 92110, France (e-mail: sepulveda.ailton@me.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved. INVITED COMMENTARY