Help Me Make it Through the Night (Shift)

Laura A. Stokowski, RN, MS


January 24, 2012

In This Article

Sleep, Fatigue, and Safety

It bears reminding that many of the worst industrial accidents in history have taken place on the night shift.[18] Over the years, nurse researchers have put their own profession under the microscope and studied the effects of fatigue on performance in nurses. The results have been equivocal, but most point to reduced performance and increased risk for errors and accidents, influencing both patient and personal safety, on the night shift.[23,29,30,31]

Following are some of the effects of fatigue:

  • Slowed reaction time;

  • Attention lapses;

  • Less attention to detail;

  • Compromised problem-solving;

  • Impaired psychomotor skills;

  • Reduced coordination; and

  • More errors of omission.

Fatigue isn't the only subjective symptom experienced by nurses working the night shift. Irritability, forgetfulness, stress, chills, nausea, and eye strain are other common complaints of night-shift nurses that could affect performance or physical and mental well-being.[32] A survey of critical care nurses found that 26% had experienced personal work injuries or near injuries, 16% had been involved in patient safety incidents, and 20% had accidents or near accidents on the drive home -- all believed to be related to fatigue.[32]

Research confirms that the ability to perform tasks declines throughout the night shift, especially during the second half of the shift. The worst performance coincides with the time when body temperature is lowest, at 0400-0600,[33]a finding supported by lower levels of perceived alertness during these hours.[34]Medication errors that occur on the night shift vs the day shift are more often reported to be a consequence of sleepiness.[31]

Even partial sleep deprivation is associated with an increased likelihood of making an error and a decreased likelihood of catching someone else's error.[28]Rotating shifts, especially more rapidly rotating schedules, are associated with increased error rates in nurses.[35] Moreover, the risk for making an error or being involved in an incident increases with of the number of successive night shifts. The risk for an incident at work is 6% higher on the second night shift, 17% higher on the third, and 36% higher on the fourth.[29]

Whether these findings are due to increasing sleep deficits on the part of night shift nurses or other factors associated with working nights is not known. Increased errors on the night shift could reasonably result from several factors, such as staff shortages, increased patient-to-nurse ratios, and reduced support and resources during off hours. Admi and colleagues[36] did not find a difference in performance or rates of error between day and night shift nurses, including nurses who were less well-adapted to working nights.

Personal safety is a significant concern for nurses who are fatigued and/or sleepy. Working the night shift has been associated with an increased risk for percutaneous needle punctures, lacerations, and consequent exposure to blood-borne pathogens.[37]Extreme drowsiness while driving or cycling home, including near-miss accidents, has been reported by nurses who work nights.[28,38] The effects of sleep deprivation on mental alertness are similar in magnitude to those seen in people with blood alcohol concentrations over the legal limit.[18]

Substantial interindividual differences in the level of cognitive and performance impairment induced by fatigue are known to exist,[39] making it difficult to predict how much sleep an individual requires to make him or her "safe." Nor is there any consensus on the extent of impairment resulting from a given amount of sleep loss.[18]


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