Tired all the time

How much sleep do we need?

Recommended hours of sleep vary. Some people are thought to be naturally “short sleepers,” needing less than six hours a night, and some are long sleepers needing more than nine hours.1 After years of being told that eight hours’ sleep a night was normal and less than this leads to sleep debt,2 we now hear that research from the US indicates that people who sleep only seven hours a night live longest.3 Research from the United Kingdom shows that when we sleep too much the quality of sleep decreases, and that rest in the form of watching television or relaxing with loved ones can be equally as refreshing.4

Perhaps the important issue is fatigue. It is known that this results in higher error rates on a range of neuropsychological functioning tasks and that lack of sleep can also interfere with cortisol 56 and serotonin levels,7 leading to the negative effects on mood state noted in fatigued doctors.8

Do naps help? Microsleeps, brief periods of sleep-like inattention, have been documented using electroencephalography in pilots and train drivers among others.9 Research by NASA on fatigue countermeasures showed that allowing pilots to take naps could reduce these events by half.2 Professor David Dinges leads the NASA research programme on naps, and though they can be helpful, he advises caution because although naps can be refreshing they can also leave you groggy (so-called sleep inertia), especially if you are working night shifts. They can improve performance in some areas in the short term but are not a substitute for a good night’s sleep.10

Does it matter?

Is this really a problem? Would junior doctors work just as well on a more demanding rota, meaning fewer handovers (which are shown to be poor for conserving information) and improved continuity of care, reducing the risk of adverse events?11

In the general working population, fatigue has long been associated with adverse incidents and injuries, ill health, poorer work performance, sick leave, and disability.5 Research as early as the 1970s showed that tired junior doctors are sadder, more uncertain, and less able to detect cardiac arrhythmias,8 and recent research showing that sleep deprivation had adverse effects on mood and performance supports this.12 In the United States, where junior doctors often work more than 80 hours a week, nearly 50% of trainees feel they have made errors owing to fatigue,13 and surgical trainees have been shown to make more errors on a laparoscopic simulator after a sleep deprived night on call than during the daytime.14

Fatigue has a detrimental effect on the mood and performance of junior doctors, but do these findings translate to adverse events and errors in the clinical setting? Doctors think they do, with three in five reporting that working long hours had compromised their ability to provide safe health care to patients.15 A 1994 BBC Horizon programme highlighted the issue of problems associated with fatigue and junior doctors’ working hours, which was followed by a BMJ review and a series of letters on the matter of fatigue in the medical profession, and its lack of regulation compared with the transport industries.16

Legislation

An increasing awareness of the problems caused by long shifts and fatigue resulted in the new deal for junior doctors in 1991. This was followed by the European Working Time Directive in 2004, setting down rules about working hours and rest time.17

Recent research from the University of Warwick18 showed that those on shorter, directive compliant rotas, had longer sleep time and made over 30% fewer errors. This is supported by a US study showing that 36% more errors were made by junior doctors on a standard rota than on a rota including more sleep.19 Such regulations, then, seem to be appropriate and improve patient care.

The stereotype of the exhausted junior doctor should be a thing of the past, therefore, but it persists. For many junior doctors I know, the simple reason for this is that they do not work the hours set down by the European Working Time Directive, and certainly they do not attain the minimum rest period requirements. This anecdotal experience is supported by figures recently published by the BMA,15 which show that nearly 50% of junior doctors in the UK still work outside the rest requirement, that half were regularly pressured to work additional hours, that 41% regularly had to do training, and that 29% had to provide service, during rostered time off.

This is worrying in the context of substantial evidence that “a tired clinician is a dangerous one.”11 Despite the changes in Europe, the working hours of clinicians are far less regulated than those of, for example, the transport industries. Should the medical profession take a leaf out of their book?

What do other industries do?

Flights are delayed if the pilot has not had the required amount of rest, but operations go ahead even when the surgeon or anaesthetist has not rested.20 Pilots are restricted in their weekly flying hours (30 in the US, 55 in the UK). They have minimum required rest periods between flights (nine hours in the US, 12 in the UK), and there are sanctions if these are exceeded.11

Until 2003, long haul truck drivers in the US averaged 3.8-5 hours’ sleep a day. Guidelines were introduced for mandatory daily rest periods and maximum hours driving in a given time period. Weekly driving hours are restricted to 60 in the US and to 48 in the UK; the minimum required rest periods are 12 in the US and 11 hours in the UK.11

An evidence based good practice guide was developed for UK train drivers to help them cope with shift work and fatigue. Recommendations were made to limit length (10 hours) and number of consecutive night shifts (three), to avoid rapid change from a late finish or night shift to an early start, and to have a rest period of 14 hours between consecutive nights.

It’s not all about sleep

There is substantial evidence in the literature, both medical and relating to other industries, that long working hours causes fatigue and that fatigue negatively affects performance. Numbers of hours worked and slept are not the only important variables though. Other work related factors contribute to fatigue, accident, and error.5

In a letter to the BMJ an occupational psychologist calls the working environment of his junior doctor son “psychotoxic.”21 Certainly there is evidence from the Maastricht Cohort Study of Fatigue at Work and other sources that high demands (physical and emotional), high effort, low control, low support, low reward, and exposure to physical hazards, combined with shift work and long hours, all common among junior doctors, are associated with work stress and fatigue.5 The same review reminds us that high job demands and role conflict were found to be associated with fatigue in a sample of NHS trust employees.5

What next?

Fatigue makes workers less psychologically healthy, more likely to become ill or have an accident, and more error prone. Long hours, shift work, and other work related factors can increase fatigue and therefore should be considered in addressing fatigue at work. These findings apply to the medical profession just as much as to other areas of work. Transport industries have introduced regulations about work and rest hours to reduce fatigue related error, but misreporting of hours is known to occur and is associated with increased fatigue.5

Internationally, junior doctors often work very long shifts with minimal rest in between.5 In Europe, the European Working Time Directive is to be fully enforced from June 2009 and should ensure that no one works more than a 48 hour week, and should also protect rest time. Although the Department of Health in the UK has applied for three year delay on this.11 Compliance with such a rota has been shown to reduce error in the clinical setting.18 This may need to be offset by more years of training for junior doctors, to ensure they acquire sufficient experience before becoming consultants. It will be important to monitor the effects of such changes in the rota, to balance any error reduction owing to less fatigued doctors against any increase in error owing to disruption in continuity of care and the increase in number of handovers. Findings from such research could be used as an evidence base to inform practice in countries where the working hours of junior doctors are in excess of those permitted under the European Working Time Directive.

So how should I summarise all of that for my concerned elderly patients who ask if I’m getting enough sleep? Perhaps I’ll just ask if they could lend me their bed for five minutes.