Nursing is a 24-hour job and, regardless of shift time or duration, nurses are expected to provide the highest quality care to patients.
Due to their substantial roles in direct patient care, the performance of nurses is closely linked to quality and safety. Evidence suggests that the nature of shift work places patient safety at risk, primarily due to nurse fatigue associated with sleep deprivation and disruption of circadian rhythm (Berger & Hobbs, 2006; de Castro et al., 2010; Lockley et al., 2007; Muecke, 2005; Rogers, 2008). The problem is significant enough that nurse fatigue has been nationally recognized as a threat to patient safety by the American Nurses Association.
Understanding Fatigue
Rogers defines fatigue as “an overwhelming sense of tiredness, lack of energy, and a feeling of exhaustion associated with impaired physical and/or cognitive function.” It is recommended that adults get approximately one hour of sleep for every two hours they are awake, which adds up to about eight or nine hours each night. Sleep debt occurs for those who do not obtain optimal amounts of sleep and accumulates for each day adequate sleep is missed, causing sleep deprivation (Admi et al., 2008; Peate, 2007; Rogers, 2008). Sleep deprivation, or lack of sleep needed to function, can have an astonishing impact on fatigue causing detrimental effects on performance (Lockley et al., 2007; Nugent, 2007; Peate, 2007; Rogers, 2008).
Effects of Fatigue and Sleep Deprivation
Fatigue and sleep deprivation can have a multitude of consequences on the mind and body. According to Rogers, insufficient sleep has been shown to cause cognitive impairments, mood alterations, and physiological changes. Studies show that fatigue is associated with reduced vigilance, judgement, and ability to concentrate; decreased situation awareness, coordination, and motor skills; as well as, slower reaction times (Berger & Hobbs, 2006; Caruso, 2014; Keller, 2009; Maltese et al, 2015; Nugent, 2007; Peate, 2007; Rogers, 2008). “Sleep deprivation also leads to irritability, bad mood, reduced communication skills and ability to cope with the emotional demands of the workplace,” Caruso wrote.
According to Caruso, fatigue and sleep deprivation can be severe enough to cause periods of involuntary sleep occurring for up to 30 seconds at a time, known as microsleep (Muecke, 2005). Sleep deprivation puts pressure on the brain to fall asleep and with high amounts of pressure, the brain can transition from wake to sleep quickly and abruptly (Caruso, 2014; Schwartz & Roth, 2008). During episodes of microsleep, a person may appear awake, but they would have no response to environmental stimuli and their brain would be incapable of processing information (Boyle, Tippin, Paul, & Rizzo, 2008; Caruso, 2014; Muecke, 2005).
Unfortunately, the effects of fatigue are insidious and not easily recognized by a sleep-deprived individual, making self-assessment of fatigue and perceived performance ability unreliable according to studies from Lockley and Rogers. This can create circumstances of unsafe care for patients when the nurse does not readily comprehend the extent to which they are suffering from the negative effects of sleep deprivation.
Shift Work and Patient Safety
Shift work is most commonly described as work taking place beyond daylight hours (6am–6pm) and may include evening and overnight timeframes (Berger & Hobbs, 2006; Caruso, 2014; Keller, 2009). Evidence exists that shift work impacts sleep and waking through disruption of circadian rhythm, according to Admi et al,. Circadian rhythm is the body’s internal clock controlling inherent patterns of sleep, alertness, and performance (Berger & Hobbs, 2006; Lockley et al., 2007; Nugent, 2007).The human body is designed to be awake during daylight and sleep during hours of darkness (Keller, 2009; Nugent, 2007). Shift work causes nurses to fight their natural instinct to sleep and attempt to sleep at irregular times, leading to a disruption in the circadian rhythm which causes sleep deprivation and fatigue (Berger & Hobbs, 2006; Caruso, 2014; Keller, 2009; Lockley et al., 2007; Nugent, 2007). According to Caruso, “misalignment of sleep with circadian rhythm leads to difficulties with falling asleep, more arousals during sleep, and early awakenings leading to poorer sleep quality and shorter sleep duration.”
On average, shift workers get one to four hours less sleep than normal while working night shift according to Rogers. Research from Berger & Hobbs as well as Caruso has found that anywhere from 26-50% of night-shift workers report severely reduced alertness, decreased sleep, excessive fatigue, or long-term insomnia. Additionally, the results of a survey study revealed that 32-36% of night-shift nurses reported falling asleep during their shift at least once per week per Rogers.
Aside from the negative effects of fatigue, the simple nature of being awake at night can present safety issues. Multiple studies have found that, due to circadian rhythm, the body is naturally less efficient between 10pm and 6am and least active from 3am to 6am, which can greatly impact the ability of a nurse to provide safe, high-quality care during these hours (Berger & Hobbs, 2006; Folkard & Tucker, 2003; Peate, 2007). Evidence from Berger & Hobbs suggests that disruptions in the sleep-wake cycle increase fatigue, decrease levels of alertness, and diminish the capacity to perform demanding tasks. Dingley states:
...sleep loss, along with the need to work at the low point of circadian cycle, increases the risk of night nurses being less alert than would ideally be the case. This may impair the efficiency with which they carry out their duties and in an extreme case could possibly endanger the life of a patient.
Due to declines in cognitive function, vigilance, and performance related to fatigue, the risk of accidents and errors increases by 15% to 28% on evening and night shifts, respectively according to Caruso’s study. One company determined that fatigue-related accidents, productivity losses, and healthcare expenses cost an estimated $116.5 billion per year in the United States. According to Muecke, “small yet vital changes in a patient’s condition or medication order errors may be overlooked by a sleep-starved nurse.” Common incidences caused by sleep deprivation and reduced attentiveness include medication administration errors, needlestick injuries, and improper operation of medical equipment as reported by Admi et al., and Berger & Hobbs. Though some errors may be harmless, others could have serious or life-threatening consequences.
Nurses aspire to provide their patients with safe and effective care 24-hours per day in efforts to achieve the best possible outcomes. However, the nature of shift work leading to high levels of nurse fatigue diminish the capacity to maintain optimal levels of care during this time. Research indicates that sleep deprivation, fatigue, and circadian misalignment are directly linked to increased accidents, lapses in performance, and errors by night-shift workers. Despite their best efforts, night shift nurses may not be able to achieve the high standard of care they strive for due to the negative effects of fatigue on performance, quality of care, and safety.