Sleep deprivation and performance

I read with interest the study on sleep deprivation and performance (Murray & Dodds. Anaesthesia 2003; 58: 520–5). I have been following the research into sleep deprivation and performance since, when driving home post ‘on call’, I found myself on the wrong side of the road with a large truck bearing down on me. This was in the bad old days of 72 h weekends, so things must be better now. But are they? While juniors are given the day off post call, and many work shifts, consultants are expected to continue with the rest of the days work. Murray and Dodds do not state when their subjects started working in the morning, but 07:00–08:00 would cover most anaesthetic consultants. If you have then been supervising juniors, covering the ICU and/or maternity while on call, it is not uncommon to be up until 02:00 the next day before you can contemplate sleep, which will then be disturbed again 4–5 h later to get up to go to work again, or possibly sooner. You may well have been up all night and are then expected to continue to work the routine list the following day, as our contracts do not recognise ‘on call’ as work. One study has equated the level of performance decrement using hand eye co-ordination after sustained wakefulness, and alcohol consumption [1]. After 18 h of wakefulness, the performance was equivalent to 0.05% blood alcohol concentration, and after 24 h, to 0.1% blood alcohol concentration. If the Trust found you to have such levels of alcohol in your blood while working, you would expect suspension and probably erasure from the medical register, and possibly criminal charges. However, if you have been working all night, it is considered acceptable to have the same level of performance, as if you had been drinking, and you still have to drive home. In subjects who were sleep deprived for 24 h, Positron Emission Tomographic scanning (PET) for the utilisation of glucose as a marker for activity, showed decreased activity in the areas of the brain involved with attention and higher order cognitive thinking [2]. Consider the case of Gary Hart, after the Selby Rail Disaster he was sentenced to 5 years in prison for causing the deaths of 10 people; in summing up Justice MacKay said: ‘In moral terms I see little to choose between a driver who sets off on a journey affected by drink and a driver setting off in your condition.’[3]. Gary hart had had little or no sleep the previous night. Therefore, continuing to work when you have the subjective feeling of tiredness (with the support of objective research evidence), could be considered a breech of General Medical Council (GMC) guidelines, on the grounds of putting the patient at risk, when you know it is unsafe to continue [4,5]. Should something happen, it is not impossible that you could be proven ‘negligent’ on the grounds of ‘forseeability’[6]. Even if you are not physically working, just being ‘on call’ will affect your sleep pattern and quality of sleep [7], which may have similar effects on your performance the next day if you had been working, as pointed out in the study. Appropriate management of this problem will result in reduced day time activity, but failure to act will continue to create risk. The problem will become more acute in August 2004 as the European Working Time Directive bites for junior doctors hours. Anaesthesia has led the way in reducing patient risk and making life bearable for its staff; surely the time has now come for both the Association and the College of Anaesthetists to get together and support further research on the topic of performance and sleep deprivation? In the meantime, there is enough evidence to suggest that it is unsafe for patient care, and the individual anaesthetist, to continue working the day after a busy ‘on call’, regardless of the grade.