An extended shift worked in a hospital is usually taken to mean a 12-hour shift. Shifts this long are attractive to employers (hospitals) because they make coverage of 24-hour care areas, namely, emergency departments, wards, and operating theatres, easier to deliver. It does not necessarily follow that the employee working the extended shift will be equally constructive throughout the shift. In one study, doctors coming off an extended shift and doctors coming off a normal shift were given simulated critically ill patients to treat. Those coming off the extended shift were less effective at decision-making and delivering care . Furthermore, productivity may also be reduced in an extended shift. In an emergency department that introduced a new, extended 12-hour shift, the rate of seeing patients reduced compared with when the previous 9-hour shift was used .
Extended shifts also pose a risk to employees. Amongst 2737 residents in the United States, the odds ratio for reporting a motor vehicle crash after an extended shift was 2.3, and for a near miss 5.9 . Working extended shifts is associated with coronary heart disease, myocardial infarction, and metabolic syndrome [4–6]. In a large observational study that included nearly a million emergency medical services shifts, in a hierarchical logistic regression analysis, compared to 12-hour shifts, for occupational injury there was a relative risk of 0.7 for 8-hour shifts, and 1.6 for the longer 16-hour shift .
Both doctors and patients also believe that shorter shifts are probably better. In one study of more than 21 000 internal medicine trainees, the majority believed that specific work regulations such as limited shift length and more time off after nights and extended shifts would at least ‘occasionally’, if not ‘usually’ or ‘always’, improve patient care . Furthermore, in a survey of in-patients, most respondents thought that doctors should not work more than 12-hour shifts, and half wanted to be informed if the doctor caring for them had worked for longer than 12 hours .
However, not all evidence suggests that extended shifts are universally detrimental. Associations with a negative outcome after reducing extended shifts is explained by the healthy worker survivor effect, that is, those that remain employed tend to be healthier than those that leave employment . There is also significant heterogeneity amongst types of shift and outcomes measured. Furthermore, peoples’ lifestyles do not always fit with shorter shifts. The benefit of an extended shift is that the number of days per week worked is likely to reduce. As a consequence, individual preference for working 12-hour shifts is thought to be a function of individuals’ own health situation, their family situation, work load tolerance, degree of sleep problems, personality. and other factors . Employees should be allowed to choose whether they work 12-hour shifts rather than have them imposed.
In the UK, the European Working Time Directive (EWTD) was implemented in 2009. Prior to the EWTD, junior doctors worked around 90 hours a week in the 1980s, which was reduced to 72 hours a week in the 1990s. The EWTD both restricts hours worked and imposes minimum rest requirements. Junior doctors may work a maximum average of 48 hours a week (calculated over 26 weeks), must have a minimum of 11 hours rest a day, a day off a week and a 20-minute rest break every six hours. The flip side to this is that there are often rota gaps which junior doctors sometimes feel obliged to fill, thus going over their maximum number of hours, and many trainees are concerned that the reduced time spent at work translates to a poorer training experience.
The perception, described in a survey of 2549 UK doctors, is that the 48-hour week leads to dissociation between rotas and actual hours worked, adverse effects on training opportunities and quality, concerns about patient safety, and lowering of morale and job satisfaction . The EWTD has previously been seen by UK doctors in extremely poor light, with the results of another survey of around 4136 doctors indicating that only 12% agreed that the EWTD had benefited the NHS, 9% thought it had benefited senior doctors and 31% thought that it had benefited junior doctors . Doctors from ‘craft’ specialties (e.g., surgery, anaesthetics) were particularly critical. However, the surveyed doctors all graduated in either 1999 or 2000, so were qualified during the implementation of EWTD. Doctors that graduated more recently indicated that they welcome more regulated working hours, but were dissatisfied with their experience of implementation . Specifically, their out of hours work, which they valued as it gave them increased opportunities for independent decision making, had been reduced. In contrast, day work, which was perceived to be heavily weighted toward administrative tasks and service provision, was not reduced.
Although the EWTD does not include specific rules about extended shifts, because it mandates an 11-hour rest in 24 hours, the longest shift that can legally be worked is 13 hours. It is rare for junior doctors to be in rotas with 12-hour shifts, but the consequent effect of rotas that include extended shifts is often a reduction in training opportunities, and because they are in a minority, a perception of lack of parity between their rota and experience, and their training peers regionally and nationally.
The average number of hours worked per week by junior doctors in the UK has gradually decreased over the last 30 years, as has the length of shift. As these reductions are normalized, with fewer doctors that remember the longer shifts and longer weeks, the calibration of what is extended gradually resets. It seems likely that extended shifts may be harmful to both employees and patients. The current paradigm may change again so that 12-hour shifts are seen to be as extreme as a 24-hour shift once was.
Conflicts of interest
There are no conflicts of interest
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