1. Hughes, Ronda G. PhD, MHS, RN
  2. Rogers, Ann E. PhD, RN, FAAN

Article Content

Most nurses have gone to work tired, cared for patients while tired, come home tired, and returned to work the next day tired. But what many nurses don't realize is that sleep loss and sleep deprivation can jeopardize not only a nurse's health but also the safety of patients.


The Institute of Medicine's report on medical errors, To Err Is Human: Building A Safer Health System, revolutionized the discussion of errors in health care: "The problem is not bad people; the problem is that the system needs to be made safer." 1 Many errors aren't reported, which makes it difficult to determine the full extent of the problem. Nonetheless, research clearly shows that many errors, especially medication errors, can be prevented. 2, 3


According to Reason, most errors are attributable to difficulties with organizational processes. 4 When nurses work more than 12 hours in a day or 60 hours in a week because of systems failures (such as staffing shortages), they are at great risk for making errors that threaten patient safety. 5 In such instances, the system, rather than the nurse, is to blame for any resulting errors. However, when work schedules and systems are organized to respect providers' needs for sleep, and a nurse ignores the impact of insufficient sleep, that nurse could be considered negligent if an error occurs.


Fatigue caused by working too many hours and sleeping too few results in profound sleepiness that can deteriorate a nurse's alertness, productivity, and safe patient care.



Most people require seven to nine hours of sleep each night. Sixty-eight percent of Americans sleep less than eight hours each weeknight. 6 The effects of sleep loss, even as little as one hour lost daily, accumulate, resulting in decrements in neurobehavioral performance (such as attention span, reaction time, and problem solving). 7 Consequences include an increased tendency to fall asleep, 8 lapses in vigilance, decreased alertness, and a longer sleep episode (that is, sleeping more than eight hours or even more than 14). 9


It is estimated that more than 70 million Americans suffer from some form of chronic, long-term sleep disorder. These disorders (including insomnia, sleep apnea, restless legs syndrome, and narcolepsy) can cause "problem sleepiness," as can certain medical conditions (asthma, congestive heart failure, and chronic pain) and drugs (caffeine, nicotine, and alcohol).


While other factors can compete with and may even increase the need for sleep (such as social activities, pregnancy, 10 or having a child under age three), insufficient sleep can affect metabolism, hormone secretion, and immunity. 11


Any form of sleep deprivation may result in the following 12-14:


* lapses in attention and inability to stay focused


* reduced motivation


* compromised problem-solving


* confusion or bewilderment


* irritability or hostility


* unusual tenseness or anxiety


* memory lapses (particularly in short-term memory)


* impaired communication


* faulty information processing and judgment


* diminished ability to detect and recognize the significance of subtle changes in a patient's health


* diminished reaction time


* slowed information processing


* inability to deal with the unexpected


* indifference and loss of empathy



A fatigued nurse may be more prone to making errors in routine, repetitive tasks-which much of their work-exhibit decreased productivity, and find it difficult-to-perform tasks (such as reading an electrocardiogram or calculating dosages). 15-17



Until recently, little was known about the impact of long work hours and little sleep on nurses. Researchers at the University of Pennsylvania (including Ann E. Rogers, coauthor of this article) surveyed 393 full-time hospital staff nurses about their work schedules, sleep habits, and errors. 18, 19 Not surprisingly, they found that nurses are not getting enough sleep. They also found that when nurses work long hours and get inadequate sleep, patients and nurses are at risk for injury.FIGURE

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These researchers were expecting to find, and did, that some night-shift nurses must fight to stay awake between 3 AM and 5 AM, when the urge to sleep is strongest. But they were surprised to find that nurses on other shifts were struggling to stay awake at work and while driving home, and that nurses were being scheduled to work shifts of up to 22 consecutive hours.



Given the nature of the circadian cycle, the best time to sleep is between midnight and 7 AM, when body temperature decreases and melatonin (a natural chemical produced at night to decrease wakefulness and encourage sleep) is released. Because of this chemical change, nurses who regularly work at night (compared with those who work permanent day or evening shifts) are more likely to report struggling to stay awake while caring for patients 20 and to report that they sleep fewer hours. Marked decreases in neurobehavioral function are associated with fatigue, leading to an increase in procedural and medication errors, especially between 4 AM and 8 AM. 21 Such impairments is even more noticeable among nurses who work rotating shifts. 22



Recovery from fatigue and sleep loss can and should occur during nonwork hours, but as is often the case, nonwork hours are filled with many commitments, leaving little room for sufficient sleep. It's important to consider the amounts of time spent asleep and awake during a day and the overall pattern of sleep, referred to as the sleep-wake cycle.


Some nurses may think that if they work only a few long days, such as three 12-hour shifts, they will be able to fully recover during days off. But fatigue has a greater impact on those working 12-hour shifts than on those working eight-hour shifts. 23


For each hour awake, the body's need for sleep increases. 24 Hence, sleep deprivation may overpower a nurse's ability to remain awake and perform her job safely. Chronic sleep loss of as little as two or three hours a night has a cumulative effect; "storing" sleep, however, does not. Periodic sleep loss and chronic sleep deprivation create what's known as "sleep debt." And attempting to "bank" sleep to offset the effects of future sleep loss will not restore any subsequent "debt" incurred. 15



The transportation industry (in particular, the airline, trucking, and railroad industries) has created strict policies limiting the number of hours an employee can work during a week as well as the amount of sleep required prior to working a shift. 5 The total number of hours that medical residents are permitted to work in hospitals during a week has been set at 80 hours. And recently, the Institute of Medicine recommended that nurses work no more than 60 hours during a seven-day period. 5


Further research is needed to assess the relationship between fatigued clinicians and medical errors. Until then, there are several steps nurses can take to improve patient safety through counteracting the effects of sleep loss and fatigue.


Use evidence-based safety practices.

Information technology, such as the computerized order entry of medications and the bar coding of pharmaceuticals, may help to overcome cognitive impairments caused by fatigue. If such technologies aren't available, ask for them. And since memory can fail, it's important to write information down and to repeat what is heard.


Get enough sleep.

Understand the importance of coming to work well rested. Although sleep needs vary, adults typically require eight hours of sleep daily to achieve optimal functioning. Prescribed medications are sometimes warranted for treatment of specific sleep disorders, but over-the-counter medications should be used with caution. 25 (For more information on the importance of sleep, see


Take uninterrupted breaks.

When you have time for a break, take it. If you don't have time for a break, make it. Inhaling your lunch or eating while you answer call lights or watch monitors is not an uninterrupted break. If you are unable to take a break because of inadequate staffing, report this fact to your manager. Without a break, your concentration and performance will be impaired. And remember: federal law mandates a 15-minute break for every four hours worked.


Limit your caffeine.

The best advice is to restrict caffeine completely; second best is to limit caffeine intake. You may be surprised to realize how addicted you are when you consider the milligrams of caffeine you take in on a regular basis (see the caffeine calculator at When you consume large amounts of caffeine, the body becomes tolerant to its effects and becomes a less-effective countermeasure against fatigue.FIGURE

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Eat well and exercise.

Start acting on the advice you give to patients. This means eating right and getting plenty of aerobic exercise. People who are partially sleep deprived tend to crave foods that are sweet and high in fat and carbohydrates; weight gain often follows, as can an altered glucose metabolism and a higher risk of type 2 diabetes mellitus.


Support a tired coworker, and let coworkers support you.

Some countermeasures that offer a limited reprieve from fatigue include taking short breaks throughout a shift, taking a walk or climbing stairs during breaks, and working closely with peers to watch for signs of drowsiness and to stay alert. It all comes down to support from peers and managers. The most effective countermeasure would be to go home and sleep and come to work well rested.


A nurse who is struggling to stay awake before or during a shift has several options. First, she might not come to work or might go home and sleep. Second, if opting to stay at work, the nurse could avoid involvement in direct patient care. And third, she could take a 15-to-30 minute nap, which would decrease the effects of sleep deprivation on work performance. 26, 27


Improve work environments to support the need for sleep.

As more is learned about the connections among fatigue, medical errors, patient safety, and nurses' health, nurses should take steps to improve work environments by supporting each staff member's need for adequate sleep. Nurses can also better manage work-related fatigue and consider strategies to improve alertness and reduce symptoms of fatigue by applying lessons from other industries, such as transportation, in which working more than eight to 12 consecutive hours without at least eight hours off is considered hazardous.


Understand the true causes of errors.

Not only is it important to investigate identifiable errors, it's also important for nurses to determine the root causes of and report near misses. Errors of omission can be linked to fatigue and the need for more sleep. If nurses continue to work schedules that inhibit sleep, errors that occur will be the fault of organizations, not individuals.




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