OBJECTIVE: The aim of this study is to explore the relationship between reported sleep, perceived fatigue and sleepiness, and cognitive performance. BACKGROUND: Although evidence suggests that fatigue and sleepiness affect the provision of care in inpatient units, there is a lack of research on the sleep patterns of emergency nurses and the effects of dis- turbed sleep and fatigue on their cognitive abilities and susceptibility to medical errors. METHODS: A quantitative correlational design was used in this study; in each of 7 different statistical models, zero-order relationships between predictors and the dependent variable were examined with appropriate inferential tests. RESULTS: Participants reported high levels of sleepiness and chronic fatigue that impeded full functioning both at work and at home. CONCLUSIONS: Although high levels of self-reported fatigue did not show any effects on cognitive function, other factors in the environment may contribute to delayed, missed, or inappropriate care. Further research is indicated. Quantitative Correlational Study’s Research Paper

Studies of worker fatigue in the military and com- mercial trucking industries1,2 suggest that long hours, especially extending into overnight, can be hazardous in terms of the potential for errors due to sleepiness and reduced vigilance. Medical providers, both nurses and physicians, are at risk because of the need for around-the-clock coverage and the number and type of decisions they must make in a given time span; in 1989, the Bell Commission Report cited sleep depri- vation in medical house officers as a major contrib- utor to the 1984 death of Libby Zion, an 18-year-old who died at New York Hospital, leading to a restruc- turing of the hours involved in medical residencies.3

The long (up to 36 hour) shifts of the medical resi- dents in charge of her care and the consequences of their fatigue on the decisions that were made were cited as factors in her death. As a result of their inves- tigation of the case, the Bell commission recommen- ded limiting the work hours of medical residents to less than 80 hours a week and no more than 24 hours in a row, and subsequent research has led to similar recommendations for the nursing workforce.4,5

Emergency care settings are chaotic environ- ments, where there is high patient turnover, constantly changing priorities and frequent changes in patient condition. High demand work settings are associated with increased fatigue, which can impair nurses_ at- tentiveness and ability not only to recognize potential errors they might commit but also to recognize and mitigate the errors of others, including physicians.6,7

The work schedules of emergency nurses (ENs) are characterized by increasing demands, irregular shifts, and long hoursVall of which challenge their mental and physical stamina. Although 12-hour shifts are

JONA � Vol. 47, No. 1 � January 2017 41 Quantitative Correlational Study’s Research Paper

Author Affiliations: Director, Institute for Emergency Nursing Research (Dr Wolf); Senior Research Associate (Mss Perhats and Delao), Emergency Nurses Association, Des Plaines; and Research Assistant Professor (Dr Martinovich), Department of Psychiatry, Northwestern University Feinberg School of Medicine, Evanston, Illinois.

The authors declare no conflicts of interest. Correspondence: Dr Wolf, Institute for Emergency Nursing

Research, Emergency Nurses Association, 915 Lee St, Des Plaines, IL 60016 (lisa.wolf@ena.org).

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal_s Web site (www.jonajournal.com).

DOI: 10.1097/NNA.0000000000000435

Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.

presented compelling evidence of increasing incident/ error rates during extended periods of work: Rates rise after 9 hours, double after 12 consecutive hours, and triple by 16 hours. Further studies have demon- strated that insufficient sleep and inadequate recov- ery time from long hours and shift work affect a nurse_s ability to provide safe, effective patient care and increase risks to personal safety.9-11 The Joint Commission_s 2011 Sentinel Event Alert on health- care worker fatigue and patient safety states that BShift length and work schedules have a significant effect on healthcare providers” quantity and quality of sleep and, consequently, on their job performance, as well as on the safety of their patients and their individual safetyIStill, while the dangers of extended work hours (912 hours) are well known, the healthcare industry has been slow to adopt changes, particularly with regard to nursingI[12(p1) Multiple studies support that a significant number of inpatient nurses have im- paired sleep quality, excessive sleepiness, and abnormal fatigue, which are associated with a greater risk of making medical errors and potentially causing harm to patients.13-15 The research of Rogers and colleagues8 Quantitative Correlational Study’s Research Paper

demonstrated that the 12-hour shift is past the point where safe decision making may be expected, and both the Agency for Health Research and Quality4

and the Institute of Medicine5 have since recommended limiting the length of nurses_ shifts. Although evidence suggests that both mental and physical fatigue and sleepiness affect the provision of care in inpatient units,16 there is a lack of research on the sleep patterns of ENs and the effects of disturbed sleep and fatigue on their cognitive abilities and susceptibility to making medical errors. The purpose of this study is to explore the relationship between reported sleep quality, per- ceived fatigue and sleepiness, and cognitive perfor- mance in a sample of ENs.

Methods

Before recruitment of subjects, institutional review board approval was obtained and the study was approved (Chesapeake Research Review, Columbia, Maryland). A Certificate of Confidentiality from the National Institutes of Health was obtained to further protect the respondents_ anonymity given the sensi- tive nature of the question. A quantitative correla- tional design was used to explore the relationship between nurses_ reported sleep patterns, perceived sleepiness and fatigue, and their ability to carry out timed cognitive tasks. As part of a 35-item online

questionnaire, participants performed 3 medication dosage calculations and correlations between fatigue and cognitive performance were measured in the same survey. Predictors were selected based on empirically based associations with work fatigue and its impact on task performance.17 In each of 7 different statistical models, zero-order relationships (ie, simple relationships that do not hold constant other predictors) between each of the predictors and the dependent variable were examined with appro- priate inferential tests.

Sample

Of the 2,419 ENs who were recruited via e-mail and social media, 2010 met eligibility criteria and consented to participate. Eligibility criteria required that study participants were English speaking, currently licensed ENs working at least 1 shift per week in a US emergency department (ED). Among those who consented, 504 survey respondents were excluded because they did not meet study criteria (eg, worked 1 shift or less in the past 30 days, did not complete survey in 1 sitting), resulting in a total sample of 1506 ENs Quantitative Correlational Study’s Research Paper