Managing Shift work and Fatigue

Acknowledging assistance from : The Massey Sleep Wake Research Centre Massey University, Wellington Dr Sarah Jay Professor Philippa Gander

Changes to Occupational Health and Safety Legislation Positive duty to proactively manage H&S in the workplace. Fatigue and Stress are workplace hazards Consequential health risks also a potential issue Requires the employer to share relevant information, give employees the opportunity to express views and contribute to decision making. Impact on people’s lives, health and wellbeing Time spent, frustration, source of aggravation in the workplace Why is this important?

A reduction in physical or mental ability as the result of physical, mental or emotional exertion that may impair nearly all physical abilities including strength, speed, response time, coordination, decision making and balance. What is Fatigue?

What causes Fatigue? Fatigue is caused by: insufficient sleep excessive wake time of day (body clock) Influenced by both work and non-work factors: Hours of work Workload Breaks Sleep and other medical conditions Family and social commitments

Sleep

Sleep is Vital; no sleep = death Human 4 to 6 days 9 to 17 days 4 to 5 days 17 to 19 days > 10 days ? Puppies Dogs (adult) Rabbits Rats Like food and water, we need sleep to survive. Sleepiness (like hunger or thirst) is a signal from the brain that you are not meeting a vital biological need. However sleepiness is different, because if you keep ignoring this message, eventually you will fall asleep, whether you want to or not. It is estimated that in the USA 20% of motorists have fallen asleep at the wheel at least once. The estimates are much higher for shiftworkers. Sleepiness is often considered a sign of laziness, or treated as a bit of a joke. However, it can have very severe consequences. It reduces our capacity to perform all types of work - physical or mental. It slows down physical reaction time and mental processing, and affects memory. It makes us more vulnerable to making mistakes. Like the effects of alcohol on performance and memory, sleep loss and sleepiness can lead to an increased risk of safety incidents and accidents at work. If you don’t get enough sleep for several nights in a row, then the effects build up day-by-day. For example, if you go for 5 days getting 2 hours less sleep than you need, you will be 10 hours “in debt” (like a bank balance). If you don’t make it up during your days off, you carry that debt forward into the next working week. Full recovery from sleep loss generally takes two nights in a row of uninterrupted sleep. We do not need to make up lost sleep hour-for-hour. Instead, recovery sleep is of a different quality. On the first recovery night, deep non-REM sleep takes priority. The second night is needed to allow enough time for REM recovery. Generally, the more active you are and the longer you are awake, the more deep non-REM sleep you have. Drummond; SRS educational slide set 2

2 Types of Sleep Wake Non-REM REM deeper as brainwaves slow down (stages 1-4) slow, regular heart rate slow, regular breathing sleep inertia waking from stages 3-4 rapid brain waves eyes moving under eyelids vivid dreaming uneven heart rate uneven breathing twitching paralysis Two types of sleep – as different from each other as sleep is from wake Exist in 3 states: wake, non-REM sleep and REM sleep REM stands for Rapid Eye Movements, which is a primary characteristic of this type of sleep. Just over 50 years a guy called Nathaniel Kleitman was interested in why infants had periods of activity and inactivity during sleep. He got a PhD student in his lab, named Eugene Aserinsky, to watch the closed eyelids of infants while they were sleeping. Aserinsky noticed that there were times when the eyelids twitched rapidly, as if the eyeball was moving rapidly behind the eyelid. They then studied adults and noticed the same thing occurring. They then tried waking adults from sleep with and without the rapid eye movements and found that people frequently recalled vivid dreams when woken from sleep with rapid eye movements. This was the discovery of REM sleep and the beginning of understanding more about the complex physiological changes that occur during sleep. Up until this point in time sleep was often though of a time of total inactivity or shutdown. When we are awake and alert our brain activity is fast. Similar brain activity is seen during REM sleep, along with the rapid movement of the eyes and the recall of dreams. Our heart rate and respiration is also often uneven and fast. However, despite all this internal activity our major muscles are completely paralysed. We are atonic. This is thought to prevent us acting out our dreams. A part of the brainstem prevents signals being sent to our major muscles. However, if you have watched a dog or cat sleep, you might have noticed tiny twitches. It is thought the signal from the brain stem is like placing a ill-fitting plug in a plug hole. Most of the water or signal is blocked, but some information gets through, resulting in the twitching. REM sleep is sometimes called paradoxical sleep – the paradox being an active mind in a paralysed body. After the discovery of the rapid eye movements Kleitman, and another PhD student, William Dement, continued to focus on sleep. They realised REM sleep was very different from sleep at other times during the night. They called the other type of sleep non-REM sleep. During non-REM sleep many of our physiological systems slow down. Brain activity slows, and our heart rate and respiration are slower and more regular than during wake, e.g. often you can tell when someone has fallen asleep by a change in their breathing. There are 4 different stages of non-REM sleep – stages 1 to 4. They can be differentiated by the speed of the brain activity occurring, with stage 4 having the slowest brain activity and being considered the deepest stage of sleep. It is most difficult to wake someone from stage 4 sleep, and when you do they are often groggy and disorientated for a while. This feeling of disorientation is known as sleep inertia. It is thought to be worst when waking from deep sleep because it takes some time to reverse the process of sleep

Non-REM/REM Cycle Wake REM Stage 1 Stage 2 Stage 3 Stage 4 0400 0500 0600 0700 Time of day (hours) Stage 3 2400 0100 0200 0300 Wake REM Stage 1 Stage 2 Stage 4 Sleep pattern of a healthy young adult Always enter sleep through non-REM stage 1 Takes about 30-40 minutes to enter first period of SWS sleep of the night. On average each cycle of non-REM, REM sleep is 90 minutes

Sleep Quantity should aim to get around 7-8h each night there are consequences for our daytime functioning when we regularly restrict sleep below about 6h per night Sleep Quantity

Increased risk for morbidity & mortality Sleep Quantity Epidemiological studies suggest that there is a U-shaped curve associated with sleep durations Both long and short sleep are associated with an increased risk of morbidity and mortality The factors mediating these relationships are unknown Increased risk for morbidity & mortality 4 7 5 6 8 9 10 Sleep Time (h) Dinges & Banks; SRS educational slide set 2

Sleep Quality Depends on sleep structure and continuity Less restorative if: increased awakenings and arousals frequent shifts to lighter stages of sleep Broken sleep does not restore you like solid sleep Factors affecting sleep quality: Age Drugs Caffeine Sleep environment Sleep disorders

Sleep Loss

The Sleep Homeostat less we sleep the harder it is to resist! wake 2300 0700 2300 0700

Effects of Sleep Loss Not enough sleep affects the brain feeling sleepier difficulty staying alert getting irritable slower reactions poorer coordination (clumsiness) poorer decision making harder to concentrate Not enough sleep affects the body increased appetite glucose intolerance weaker immune system Gastrointestinal impacts….. Like food and water, we need sleep to survive. Sleepiness (like hunger or thirst) is a signal from the brain that you are not meeting a vital biological need. However sleepiness is different, because if you keep ignoring this message, eventually you will fall asleep, whether you want to or not. It is estimated that in the USA 20% of motorists have fallen asleep at the wheel at least once. The estimates are much higher for shiftworkers. Sleepiness is often considered a sign of laziness, or treated as a bit of a joke. However, it can have very severe consequences. It reduces our capacity to perform all types of work - physical or mental. It slows down physical reaction time and mental processing, and affects memory. It makes us more vulnerable to making mistakes. Like the effects of alcohol on performance and memory, sleep loss and sleepiness can lead to an increased risk of safety incidents and accidents at work. If you don’t get enough sleep for several nights in a row, then the effects build up day-by-day. For example, if you go for 5 days getting 2 hours less sleep than you need, you will be 10 hours “in debt” (like a bank balance). If you don’t make it up during your days off, you carry that debt forward into the next working week. Full recovery from sleep loss generally takes two nights in a row of uninterrupted sleep. We do not need to make up lost sleep hour-for-hour. Instead, recovery sleep is of a different quality. On the first recovery night, deep non-REM sleep takes priority. The second night is needed to allow enough time for REM recovery. Generally, the more active you are and the longer you are awake, the more deep non-REM sleep you have.

Total Sleep Deprivation

Sleep Loss v Alcohol Intoxication Sustained wakefulness 2300 0800 1200 Like food and water, we need sleep to survive. Sleepiness (like hunger or thirst) is a signal from the brain that you are not meeting a vital biological need. However sleepiness is different, because if you keep ignoring this message, eventually you will fall asleep, whether you want to or not. It is estimated that in the USA 20% of motorists have fallen asleep at the wheel at least once. The estimates are much higher for shiftworkers. Sleepiness is often considered a sign of laziness, or treated as a bit of a joke. However, it can have very severe consequences. It reduces our capacity to perform all types of work - physical or mental. It slows down physical reaction time and mental processing, and affects memory. It makes us more vulnerable to making mistakes. Like the effects of alcohol on performance and memory, sleep loss and sleepiness can lead to an increased risk of safety incidents and accidents at work. If you don’t get enough sleep for several nights in a row, then the effects build up day-by-day. For example, if you go for 5 days getting 2 hours less sleep than you need, you will be 10 hours “in debt” (like a bank balance). If you don’t make it up during your days off, you carry that debt forward into the next working week. Full recovery from sleep loss generally takes two nights in a row of uninterrupted sleep. We do not need to make up lost sleep hour-for-hour. Instead, recovery sleep is of a different quality. On the first recovery night, deep non-REM sleep takes priority. The second night is needed to allow enough time for REM recovery. Generally, the more active you are and the longer you are awake, the more deep non-REM sleep you have.

Chronic Sleep Restriction Not getting enough sleep over several nights/days (<6h per night) Accumulate a sleep debt Consequences can be as severe as those associated with total sleep deprivation Like food and water, we need sleep to survive. Sleepiness (like hunger or thirst) is a signal from the brain that you are not meeting a vital biological need. However sleepiness is different, because if you keep ignoring this message, eventually you will fall asleep, whether you want to or not. It is estimated that in the USA 20% of motorists have fallen asleep at the wheel at least once. The estimates are much higher for shiftworkers. Sleepiness is often considered a sign of laziness, or treated as a bit of a joke. However, it can have very severe consequences. It reduces our capacity to perform all types of work - physical or mental. It slows down physical reaction time and mental processing, and affects memory. It makes us more vulnerable to making mistakes. Like the effects of alcohol on performance and memory, sleep loss and sleepiness can lead to an increased risk of safety incidents and accidents at work. If you don’t get enough sleep for several nights in a row, then the effects build up day-by-day. For example, if you go for 5 days getting 2 hours less sleep than you need, you will be 10 hours “in debt” (like a bank balance). If you don’t make it up during your days off, you carry that debt forward into the next working week. Full recovery from sleep loss generally takes two nights in a row of uninterrupted sleep. We do not need to make up lost sleep hour-for-hour. Instead, recovery sleep is of a different quality. On the first recovery night, deep non-REM sleep takes priority. The second night is needed to allow enough time for REM recovery. Generally, the more active you are and the longer you are awake, the more deep non-REM sleep you have.

TOTAL SLEEP TIME Belenky et al, J. Sleep Res, 2003

RESPONSE TIME PERFORMANCE Belenky et al, J. Sleep Res, 2003

Chronic Sleep Restriction v Total Sleep Deprivation PVT = psychomotor vigilance task a standard way of assessing fatigue Van Dongen et al, Sleep, 2003

Time of Day

Circadian Rhythms physiological processes that occur rhythmically and persist with an endogenous period of approximately 24-hours in the absence of environmental time cues Circadian clock is synchronised by external cues: day/night cycle social cues work patterns

The Circadian Clock The circadian clock regulates many of our physiological and behavioural processes of which sleep is only one e.g core body temperature hormone production alertness/sleepiness performance

Time 4 pm midnight 8 am 4 pm Sleep Sleep Evening wake maintenance zone Temperature low point Sleepiness ↑↑

The basic problem with shift work is that it requires trying to override the body clock’s preference for sleep at night. The clock cannot adapt, even to permanent night work, because it is always being drawn back to its preferred pattern by the day/night cycle and the rest of day-active society. People also tend to go back to sleeping at night on their days off. This means shiftworkers (particularly people working at night) often have to work through times in the body clock cycle when they are least functional and most prone to making errors. They then have to try to sleep when the clock is gearing the brain and body up to be awake, and when other distractions affecting sleep are greatest. Problems sleeping are among the most common complaints of shiftworkers. As we saw earlier, not getting enough sleep also makes you less functional and more prone to error. There is a major split in thinking about the best way to get around these problems. One argument is that the longer you stay on a shift, the more you adapt to it, so shift rotations should be slow (1-3 weeks on each shift). This overlooks the fact that the body clock resists adaptation, and the fact that most people sleep at night on their days off. The other argument is based on the expectation that the clock is not going to adapt completely to different shifts. Therefore, the strategy is to rotate shifts very rapidly (every 2-3 days), so it adapts as little as possible. Then people should have no trouble getting a good night’s sleep on their days off. As in most issues to do with rostering, there is no one right answer for all situations. The specifics of each situation need to be considered. Dijk & Edgar, 1999

Shift Work

Shift Work: physiological definition Not just night work Not just rotating schedules but fixed schedules as well “any work pattern that requires you to change your sleep pattern” Shift Work: physiological definition

Advantages of Shift Work Easier access to shopping, recreation & government facilities Reduced reliance on paid child care Greater attendance at family, social & school functions during the day Travelling outside of peak times Increased income Greater flexibility of work-times Advantages of Shift Work

Problems With Shift work The clock can’t adapt the day/night cycle and the rest of society don’t change Trying to work when least functional Trying to sleep when primed for wake The basic problem with shift work is that it requires trying to override the body clock’s preference for sleep at night. The clock cannot adapt, even to permanent night work, because it is always being drawn back to its preferred pattern by the day/night cycle and the rest of day-active society. People also tend to go back to sleeping at night on their days off. This means shiftworkers (particularly people working at night) often have to work through times in the body clock cycle when they are least functional and most prone to making errors. They then have to try to sleep when the clock is gearing the brain and body up to be awake, and when other distractions affecting sleep are greatest. Problems sleeping are among the most common complaints of shiftworkers. As we saw earlier, not getting enough sleep also makes you less functional and more prone to error. There is a major split in thinking about the best way to get around these problems. One argument is that the longer you stay on a shift, the more you adapt to it, so shift rotations should be slow (1-3 weeks on each shift). This overlooks the fact that the body clock resists adaptation, and the fact that most people sleep at night on their days off. The other argument is based on the expectation that the clock is not going to adapt completely to different shifts. Therefore, the strategy is to rotate shifts very rapidly (every 2-3 days), so it adapts as little as possible. Then people should have no trouble getting a good night’s sleep on their days off. As in most issues to do with rostering, there is no one right answer for all situations. The specifics of each situation need to be considered.

Clock can’t adapt Clock doesn’t adapt – EXPLAIN THIS EXAMPLE This creates problems in terms of Sleep (esp during the day) and Fatigue at work (esp at night) Cargo… talk in terms of NOT adapting and how tired they are when having to work … regardless of sleep that they are obtaining…

Shift Work and Sleep Trying to sleep when primed for wake Trying to sleep when there is most distraction other time demands noise light heat Over the course of a roster, may accumulate a significant sleep debt The basic problem with shift work is that it requires trying to override the body clock’s preference for sleep at night. The clock cannot adapt, even to permanent night work, because it is always being drawn back to its preferred pattern by the day/night cycle and the rest of day-active society. People also tend to go back to sleeping at night on their days off. This means shiftworkers (particularly people working at night) often have to work through times in the body clock cycle when they are least functional and most prone to making errors. They then have to try to sleep when the clock is gearing the brain and body up to be awake, and when other distractions affecting sleep are greatest. Problems sleeping are among the most common complaints of shiftworkers. As we saw earlier, not getting enough sleep also makes you less functional and more prone to error. There is a major split in thinking about the best way to get around these problems. One argument is that the longer you stay on a shift, the more you adapt to it, so shift rotations should be slow (1-3 weeks on each shift). This overlooks the fact that the body clock resists adaptation, and the fact that most people sleep at night on their days off. The other argument is based on the expectation that the clock is not going to adapt completely to different shifts. Therefore, the strategy is to rotate shifts very rapidly (every 2-3 days), so it adapts as little as possible. Then people should have no trouble getting a good night’s sleep on their days off. As in most issues to do with rostering, there is no one right answer for all situations. The specifics of each situation need to be considered.

Total sleep time when working night shifts and/or morning shifts is typically reduced compared to day shifts Shift workers are a risk of accumulating significant sleep debt - Sleep Debt

Sleep Debt – Cargo Pilots

Sleeping can be disturbed even when sleeping at night On-call presents a unique set of issues when it comes to fatigue management and rostering Sleep and on-call

Sleep when On Call Total Sleep Time (hrs) Not OC OC recalled OC phone 7 6 5 4 Total Sleep Time (hrs) 3 2 1 Not OC OC recalled OC phone call(s) OC undisturbed

Managing shift work and Fatigue

Managing shift work Shift work has been identified as an occupational hazard (Health and Safety in Employment Act) i.e. has the potential to cause harm in the same way as operating heavy machinery or working with chemicals. employers must ensure that rosters take account of the impacts of work patterns, give workers adequate time to recover between shifts and between rosters/schedules. employees must report fit for work and behave safely in the workplace

Fatigue Management In any 24h operation, fatigue will be an issue fatigue cannot be prevented but can be managed managing this risk can happen on a number of levels and needs both a commitment from management and individuals Alcohol can have major effects on sleep. A couple of beers or glasses of wine before bed (with individual variations), can effectively block all REM sleep in the first half of the night. This can lead to alcohol withdrawal effects in the second half of the night, including broken sleep, nightmares, and sweats. Many people use alcohol to help them relax and fall asleep. One NASA study found pilots flying long duty days on domestic routes in the USA drank three times as much alcohol after a day’s work than they would normally drink at home. They were trying to relax and get to sleep early, anticipating an early duty start the next day. Alcohol interacts very strongly with sleepiness. If you are already sleepy, alcohol will have a much stronger effect on your performance than if you are well-rested. Used carefully, sleeping pills can offer short-term help if you are having problems sleeping. However, most do not give you normal non-REM/REM sleep patterns and effects of taking them for long periods of time are largely unknown. (Do they keep helping you sleep? Are there long-term side effects?). If you have a chronic sleep problem, then it is important to find out what is causing it. Please see your doctor. There are many types of medicine (other than sleeping pills), both prescribed and over-the-counter, that can affect your sleep. Depending on how they act, they may make it harder to fall asleep, or reduce the amount or quality of your sleep. This will make you sleepier at work. Your safety depends on your alertness. Make sure your doctor knows what you do for a job and whether you drive at night. If you are put on medication which may affect your sleep or alertness level, you may want to discuss it with your supervisor.

Risk Factors for workplace Incidents What shift characteristics are associated with increased risk of accidents and injuries? Shift Type Successive Shifts Hours of Duty Time Since Last Break Rosters need to consider all these things Folkard & Tucker (2003)

Alcohol can have major effects on sleep Alcohol can have major effects on sleep. A couple of beers or glasses of wine before bed (with individual variations), can effectively block all REM sleep in the first half of the night. This can lead to alcohol withdrawal effects in the second half of the night, including broken sleep, nightmares, and sweats. Many people use alcohol to help them relax and fall asleep. One NASA study found pilots flying long duty days on domestic routes in the USA drank three times as much alcohol after a day’s work than they would normally drink at home. They were trying to relax and get to sleep early, anticipating an early duty start the next day. Alcohol interacts very strongly with sleepiness. If you are already sleepy, alcohol will have a much stronger effect on your performance than if you are well-rested. Used carefully, sleeping pills can offer short-term help if you are having problems sleeping. However, most do not give you normal non-REM/REM sleep patterns and effects of taking them for long periods of time are largely unknown. (Do they keep helping you sleep? Are there long-term side effects?). If you have a chronic sleep problem, then it is important to find out what is causing it. Please see your doctor. There are many types of medicine (other than sleeping pills), both prescribed and over-the-counter, that can affect your sleep. Depending on how they act, they may make it harder to fall asleep, or reduce the amount or quality of your sleep. This will make you sleepier at work. Your safety depends on your alertness. Make sure your doctor knows what you do for a job and whether you drive at night. If you are put on medication which may affect your sleep or alertness level, you may want to discuss it with your supervisor.

Alcohol can have major effects on sleep Alcohol can have major effects on sleep. A couple of beers or glasses of wine before bed (with individual variations), can effectively block all REM sleep in the first half of the night. This can lead to alcohol withdrawal effects in the second half of the night, including broken sleep, nightmares, and sweats. Many people use alcohol to help them relax and fall asleep. One NASA study found pilots flying long duty days on domestic routes in the USA drank three times as much alcohol after a day’s work than they would normally drink at home. They were trying to relax and get to sleep early, anticipating an early duty start the next day. Alcohol interacts very strongly with sleepiness. If you are already sleepy, alcohol will have a much stronger effect on your performance than if you are well-rested. Used carefully, sleeping pills can offer short-term help if you are having problems sleeping. However, most do not give you normal non-REM/REM sleep patterns and effects of taking them for long periods of time are largely unknown. (Do they keep helping you sleep? Are there long-term side effects?). If you have a chronic sleep problem, then it is important to find out what is causing it. Please see your doctor. There are many types of medicine (other than sleeping pills), both prescribed and over-the-counter, that can affect your sleep. Depending on how they act, they may make it harder to fall asleep, or reduce the amount or quality of your sleep. This will make you sleepier at work. Your safety depends on your alertness. Make sure your doctor knows what you do for a job and whether you drive at night. If you are put on medication which may affect your sleep or alertness level, you may want to discuss it with your supervisor.

Alcohol can have major effects on sleep Alcohol can have major effects on sleep. A couple of beers or glasses of wine before bed (with individual variations), can effectively block all REM sleep in the first half of the night. This can lead to alcohol withdrawal effects in the second half of the night, including broken sleep, nightmares, and sweats. Many people use alcohol to help them relax and fall asleep. One NASA study found pilots flying long duty days on domestic routes in the USA drank three times as much alcohol after a day’s work than they would normally drink at home. They were trying to relax and get to sleep early, anticipating an early duty start the next day. Alcohol interacts very strongly with sleepiness. If you are already sleepy, alcohol will have a much stronger effect on your performance than if you are well-rested. Used carefully, sleeping pills can offer short-term help if you are having problems sleeping. However, most do not give you normal non-REM/REM sleep patterns and effects of taking them for long periods of time are largely unknown. (Do they keep helping you sleep? Are there long-term side effects?). If you have a chronic sleep problem, then it is important to find out what is causing it. Please see your doctor. There are many types of medicine (other than sleeping pills), both prescribed and over-the-counter, that can affect your sleep. Depending on how they act, they may make it harder to fall asleep, or reduce the amount or quality of your sleep. This will make you sleepier at work. Your safety depends on your alertness. Make sure your doctor knows what you do for a job and whether you drive at night. If you are put on medication which may affect your sleep or alertness level, you may want to discuss it with your supervisor.

Self Management Strategies Keeping track of your sleep Keeping track of how long you’ve been awake Utilising given sleep opportunities Recognising signs and symptoms of fatigue in yourself and colleagues Fatigue countermeasures Self Management Strategies

Monitoring your sleep How much sleep did you get last night? How much the night before? How much on your last day off? What affects your sleep? Caffeine is a stimulant. You can use it strategically when you know you need something to help you stay awake. It will be more effective if you don’t use it continuously. Avoid caffeine when you are already alert, for example at the beginning of a drive or after a nap. Save it for the really hard times, like the 3:00-5:00 am dip, or the afternoon nap window. Caffeine usually takes about 15-45 minutes to have an effect, so you can drink coffee before a short nap. People differ widely in their sensitivity to caffeine. This depends on such things as your body size, previous food intake, and how much you regularly use. The stimulant effects of caffeine generally last 3-5 hours, but can last up to 10 hours in sensitive people, so it is important to pay attention to how it affects you. You need to stop taking it far enough in advance of bedtime so that it doesn’t interfere with your sleep. Some researchers recommend stopping caffeine as much as 6 hours before bedtime. Caffeine also activates your kidneys (is a diuretic) so it makes you urinate more. If you are drinking a lot of caffeine, then you will need to drink other fluids to stay hydrated. To stay hydrated and eat well on the job, you may need to do some planning, and take what you need with you to work.

Sleep Environment Sleep environment Very important for dark room use mask or heavy curtains quiet room turn off the phone use ear plugs comfortable temperature comfortable surface Very important for night-workers sleeping during the day Sleep Environment

Drugs and Sleep Alcohol Sleeping pills Prescription medications can help you fall asleep BUT… blocks REM sleep early in the night withdrawal later in the night - dreams, disturbed sleep Sleeping pills most don’t give normal sleep structure (non-REM / REM) effects can last too long and make you sleepy at work can have side effects, interact with alcohol Prescription medications can disturb sleep beta blockers, theophylline, Prozac Alcohol can have major effects on sleep. A couple of beers or glasses of wine before bed (with individual variations), can effectively block all REM sleep in the first half of the night. This can lead to alcohol withdrawal effects in the second half of the night, including broken sleep, nightmares, and sweats. Many people use alcohol to help them relax and fall asleep. One NASA study found pilots flying long duty days on domestic routes in the USA drank three times as much alcohol after a day’s work than they would normally drink at home. They were trying to relax and get to sleep early, anticipating an early duty start the next day. Alcohol interacts very strongly with sleepiness. If you are already sleepy, alcohol will have a much stronger effect on your performance than if you are well-rested. Used carefully, sleeping pills can offer short-term help if you are having problems sleeping. However, most do not give you normal non-REM/REM sleep patterns and effects of taking them for long periods of time are largely unknown. (Do they keep helping you sleep? Are there long-term side effects?). If you have a chronic sleep problem, then it is important to find out what is causing it. Please see your doctor. There are many types of medicine (other than sleeping pills), both prescribed and over-the-counter, that can affect your sleep. Depending on how they act, they may make it harder to fall asleep, or reduce the amount or quality of your sleep. This will make you sleepier at work. Your safety depends on your alertness. Make sure your doctor knows what you do for a job and whether you drive at night. If you are put on medication which may affect your sleep or alertness level, you may want to discuss it with your supervisor.

Strategic use of Caffeine Usual dose 50-200 mg Peak blood levels 30-60 minutes later Half-life 3-5 hours Effects on sleep Postpones sleep onset Reduces amount of stage 3 and 4 sleep Decreases sleep efficiency Caffeine is a stimulant. You can use it strategically when you know you need something to help you stay awake. It will be more effective if you don’t use it continuously. Avoid caffeine when you are already alert, for example at the beginning of a drive or after a nap. Save it for the really hard times, like the 3:00-5:00 am dip, or the afternoon nap window. Caffeine usually takes about 15-45 minutes to have an effect, so you can drink coffee before a short nap. People differ widely in their sensitivity to caffeine. This depends on such things as your body size, previous food intake, and how much you regularly use. The stimulant effects of caffeine generally last 3-5 hours, but can last up to 10 hours in sensitive people, so it is important to pay attention to how it affects you. You need to stop taking it far enough in advance of bedtime so that it doesn’t interfere with your sleep. Some researchers recommend stopping caffeine as much as 6 hours before bedtime. Caffeine also activates your kidneys (is a diuretic) so it makes you urinate more. If you are drinking a lot of caffeine, then you will need to drink other fluids to stay hydrated. To stay hydrated and eat well on the job, you may need to do some planning, and take what you need with you to work.

Napping A short nap can improve alertness for a few hours Timing is important as a nap can make it hard to initiate sleep later on Sleep inertia - grogginess that lasts about 1/2hr, performance can be impaired Caffeine is a stimulant. You can use it strategically when you know you need something to help you stay awake. It will be more effective if you don’t use it continuously. Avoid caffeine when you are already alert, for example at the beginning of a drive or after a nap. Save it for the really hard times, like the 3:00-5:00 am dip, or the afternoon nap window. Caffeine usually takes about 15-45 minutes to have an effect, so you can drink coffee before a short nap. People differ widely in their sensitivity to caffeine. This depends on such things as your body size, previous food intake, and how much you regularly use. The stimulant effects of caffeine generally last 3-5 hours, but can last up to 10 hours in sensitive people, so it is important to pay attention to how it affects you. You need to stop taking it far enough in advance of bedtime so that it doesn’t interfere with your sleep. Some researchers recommend stopping caffeine as much as 6 hours before bedtime. Caffeine also activates your kidneys (is a diuretic) so it makes you urinate more. If you are drinking a lot of caffeine, then you will need to drink other fluids to stay hydrated. To stay hydrated and eat well on the job, you may need to do some planning, and take what you need with you to work.

Increasing alertness at work Fatigue countermeasures include; Taking a break Working in pairs Having a nap Strategic use of caffeine Task reallocation Caffeine is a stimulant. You can use it strategically when you know you need something to help you stay awake. It will be more effective if you don’t use it continuously. Avoid caffeine when you are already alert, for example at the beginning of a drive or after a nap. Save it for the really hard times, like the 3:00-5:00 am dip, or the afternoon nap window. Caffeine usually takes about 15-45 minutes to have an effect, so you can drink coffee before a short nap. People differ widely in their sensitivity to caffeine. This depends on such things as your body size, previous food intake, and how much you regularly use. The stimulant effects of caffeine generally last 3-5 hours, but can last up to 10 hours in sensitive people, so it is important to pay attention to how it affects you. You need to stop taking it far enough in advance of bedtime so that it doesn’t interfere with your sleep. Some researchers recommend stopping caffeine as much as 6 hours before bedtime. Caffeine also activates your kidneys (is a diuretic) so it makes you urinate more. If you are drinking a lot of caffeine, then you will need to drink other fluids to stay hydrated. To stay hydrated and eat well on the job, you may need to do some planning, and take what you need with you to work.

Age Sleep changes across the lifespan Children: sleep more, ↑ Slow Wave Sleep About age 50 sleep at night becomes lighter, more disturbed, shorter sleepiness during the day increases There are well recognised changes in sleep with increasing age. It probably has the greatest influence on sleep The most marked structural change is the decline in SWS that begins in early adulthood. It has also been shown that there is an increase in the lighter stages of non-REM sleep (probably due to a reduction in the amount of SWS obtained), decreased sleep duration, decreased sleep efficiency, and an increased number of nocturnal awakenings, particularly in the early morning (Carrier et al., 2001). Napping is also more frequent in older individuals (Bliwise, 2000). Older individuals often report poorer quality sleep, and report difficulty falling asleep or staying asleep. Age is also associated with an increased prevalence of snoring and sleep apnoea

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