Identify the data analysis methods used and explain why the methods are appropriate based on the research question.

Research question: Is napping an effective countermeasure to sleepiness and fatigue for night-shift nurses?

Title: Napping on the night shift: A two-hospital implementation project.

Abstract

Background:Nurses who work the night shift often experience high levels of sleepiness. Napping has been adopted as an effective countermeasure to sleepiness and fatigue in other safety-sensitive industries, but has not had widespread acceptance in nursing.

Purpose:To assess the barriers to successful implementation of night-shift naps and to describe the nap experiences of night-shift nurses who took naps.

Methods:In this two-hospital pilot implementation project, napping on the night shift was offered to six nursing units for which the executive nursing leadership had given approval. Unit nurse managers' approval was sought, and where granted, further explanation was given to the unit's staff nurses. A nap experience form, which included the Karolinska Sleepiness Scale, was used to assess pre-nap sleepiness level, nap duration and perceived sleep experience, post-nap sleep inertia, and the perceived helpfulness of the nap. Nurse managers and staff nurses were also interviewed at the end of the three-month study period.

Results:Successful implementation occurred on only one of the six units, with partial success seen on a second unit. Barriers primarily occurred at the point of seeking the unit nurse managers' approval. On the successful unit, 153 30-minutes naps were taken during the study period. A high level of sleepiness was present at the beginning of 44% of the naps. For more than half the naps, nurses reported achieving either light (43%) or deep (14%) sleep. Sleep inertia was rare. The average score of helpfulness of napping was high (7.3 on a 1-to-10 scale). Nurses who napped reported being less drowsy while driving home after their shift.

Conclusion:These data suggest that when barriers to napping are overcome, napping on the night shift is feasible and can reduce nurses' workplace sleepiness and drowsy driving on the way home. Addressing nurse managers' perceptions of and concerns about napping may be essential to successful implementation.

The two-process model of sleep.Conceptually, the benefits of napping can best be understood by considering the two-process model of sleep, first described by Borbly.20This model holds that sleep is regulated by two interactive processes: sleep-wake homeostasis and circadian rhythm. The homeostatic drive to sleep, often called sleep pressure, increases with every hour awake and reduces rapidly at next sleep onset. The circadian drive for wakefulness, often called waking pressure, follows a more nuanced pattern: it increases at daybreak, dips in early afternoon between 1 PM and 3 PM, increases to a peak level between 7 PM and 9 PM, and then decreases during the night, reaching its lowest point between 2 AM and 6 AM.21In night-shift workers the natural interaction of these forces is disrupted, such that, in the middle of the night, high sleep pressure exists unopposed by waking pressure, resulting in a high level of sleepiness.Normal sleep involves two sleep statesnon-rapid eye movement (NREM) and rapid eye movement (REM)and four sleep stages, ranging from a transition stage (NREM stage 1) and light sleep (NREM stage 2) to deep sleep (NREM stage 3 and REM stage 4), with the sleeper cycling through all four stages several times a sleep period. During short naps (20 to 30 minutes), the sleeper will usually experience stage 1 or 2 sleep only, since stage 3 sleep typically occurs after about 30 to 45 minutes of sleep time. Thus a short nap can reduce sleep pressure without inducing sleep inertia (the groggy feeling that some people feel when awakened from deep sleep22).

METHODSSetting.This pilot study of a napping implementation project was one component of a study of fatigue risk management implementation initiatives in two mid-Atlantic hospitals. One is a 380-bed community teaching hospital, and the other a 313-bed children's hospital. Both hospitals have received Magnet recognition from the American Nurses Credentialing Center.Procedures.Initial study approval was obtained from the directors of nursing research, the nursing research councils, and the vice presidents for nursing at each hospital. Approval was also obtained from each hospital's institutional review board (IRB) and from the University of Maryland's IRB. Six nursing units were then selected collaboratively by the nursing research directors and executive nursing leadership. Unit selection took place between October 2011 and May 2012. The selected units included medical-surgical, critical care, and ED units.

The process of engaging the units was the same in both settings. Between January and October 2012, the principal investigator (JGB) met with each nurse manager and her designates (nurse educators, senior nurses, or a staff nurse designated as the project "point person"), and provided information about the risks of sleepiness on the night shift, the scientific evidence supporting napping, and methods to avoid post-nap sleep inertia. Each unit was encouraged to develop its own evidence-based method of implementing napping (seeTable 1,7, 22, 24, 25, 30-35). Nurse managers often delegated implementation to their senior nursing staff. When requested, the principal investigator introduced the study to nurses verbally during change of shift meetings.

Data collection with staff nurses took place between February 2012 and May 2013. Nurse managers were interviewed at the end of the data collection period, and night-shift nurses were also interviewed as a group on the unit where napping was successful. These interviews took place during February 2014, and written notes were taken.

Measures.A single-page nap experience form was used by napping nurses to document aspects of the nap. Nurses were asked to complete the form each time they took a nap. Data gathered included the timing and duration of the nap, sleepiness level immediately before the nap, sleep ability during the nap, sleep inertia upon arising, and helpfulness of the nap. No unique identifiers were collected. The nap experience form incorporated the following tools.

Sleepiness levels immediately before napping were assessed using the Karolinska Sleepiness Scale (KSS). This scale rates sleepiness on an ordinal scale ranging from 1 to 9, with 1 representing extremely alert, 5 representing neither alert nor sleepy, and 9 representing very sleepy, great effort to keep awake, fighting sleep. Ratings of 7 to 9 indicate levels of sleepiness that can impair workplace safety. The KSS is widely used in sleep science to describe state of sleepiness,36and has been validated against performance and electroencephalographic variables.37Sleep ability during the nap was assessed using an investigator-developed four-point ordinal scale (1, awake, eyes closed; 2, eyes closed, not sure if I fell asleep; 3, slept lightly; 4, slept deeply). Sleep inertia on arising was measured using an investigator-developed four-point scale (1, very groggy or sluggish; 2, a little groggy or sluggish; 3, alert, not refreshed; 4, alert and refreshed). The perceived helpfulness of the nap was assessed using an investigator-developed visual analog scale in which participants marked a line to rate their nap somewhere between "not at all helpful" (rated 0) and "extremely helpful" (rated 10).

In order to ensure participants' anonymity, we did not collect demographic data.

Data analysis.Data were described based on the level of measurement, and graphs were produced to display the relative proportions of the variables.

RESULTSNapping uptake.Napping was implemented on two of the six units, but in only one of these could implementation be deemed successful. Napping was not implemented on the other four units.

On the four units that did not implement napping, which included a medical-surgical unit, two ICUs, and an ED unit, several barriers were identified. On three of these units, the nurse managers declined the invitation to implement napping without presenting it to the staff or attempting implementation. One nurse manager stated that she felt it wouldn't be feasible to implement napping because her unit covered rapid response team calls, and she was afraid of short staffing during an event or a delay in responding; she also felt there was no feasible and acceptable napping space on the nursing unit or nearby. Another nurse manager stated that although nurses on her unit worked 12-hour shifts, they didn't take formal breaks; they just ate at the nursing station when they had an opportunity. She didn't think napping could be successfully implemented on her unit. The third nurse manager felt that the quality of nursing care would not be as good if nurses took naps. The layout of that unit was such that other nurses wouldn't be able to see the cardiac monitors assigned to the napping nurse without running back and forth. On the fourth unit (the medical-surgical unit), the nurse manager accepted the invitation to implement napping and presented it to staff. Implementation activities were begun, including designating a space and bedding for napping; but the implementation was not completed. A severe winter storm struck the area early in the implementation process, and the napping space was used to house staff who were staying over. After the weather cleared, the unit didn't continue with implementation because of reduced staff and high unit acuity.

On two units, napping was implemented and nurses actually did nap; but on one of these units, implementation was ultimately unsuccessful. On that unit (an ICU), the nurse manager established napping space in a conference room that wasn't used at night, appointed a staff nurse as the project's "champion," and verbally supported the project during staff meetings. Ten nurses on the unit tried napping over the three-month course of the study, but none took a second nap. An interview with the manager revealed that the nurses were frequently called in to work on their days off because, for budgetary reasons, a hospital-wide staffing change had eliminated staffing margins. She stated that although nurse-to-patient ratios had not changed, the unit climate had: it was less relaxed, with a greater sense of resource scarcity. She felt the climate was not right for implementing napping. The staff nurse champion felt that there was a stigma attached to napping, despite reassurances that naps are acceptable and can be helpful.

On the unit where implementation was successful (a medical-surgical unit), there was excellent uptake of napping, with 153 30-minute naps taken during the three months of the project's implementation. On this unit, the nursing director met with supervisors and charge nurses before implementation to discuss their concerns and perceived barriers to napping. The discussion focused on how to overcome barriers and create a secure environment for napping. Once the charge nurses' concerns were addressed, staff nurses were engaged in deciding how to begin the napping program. Several nurses had experienced napping in other settings and actively promoted it to peers. A napping space was chosen that would allow sleeping nurses complete privacy. At the start of the shift, nap breaks were planned along with patient care assignments, ensuring coverage for napping nurses. Nurses on this unit already took planned breaks; and they already used a "buddy" system to cover patient care and had developed a very high level of trust with one another.

(It's worth noting that after the three-month trial period ended, the nurses on this unit continued napping but modified the protocol to be more liberal, allowing 30 minutes of sleep time plus five minutes before and after for settling into bed and transitioning back to work. In the same hospital, two other units that had not been included in the study approached the primary investigator to learn how to implement napping. The hospital's shared governance committees are currently exploring opportunities to implement napping more widely.)