The humming of the florescent lights in the quiet of the night shift on the bone marrow transplant unit at Presbyterian/St. Luke’s Medical Center in Denver, CO, doesn’t bother ONS member Pam Richardson, BSN, RN, OCN®, at all; in fact, she hardly notices it.
“Working the night shift has its perks,” she reflects. “I think that nurses can forget how scary it is to be a hospital patient—all the terminology, the fast pace, the noisy equipment. Night shift nurses have the opportunity to work with patients who can let their guard down. It’s at night when visitors are at a minimum and the atmosphere is perhaps more conducive to healing.”
But there are tradeoffs. “Although night shift nurses have more autonomy,” Richardson says, “I definitely miss the interaction and learning that comes with working with other members of a multidisciplinary care team. Plus, nobody wants to make that midnight call to a sleeping provider for a throat lozenge.”
Like Richardson, 61% of RNs work in hospitals where 24-hour care is a must. In answer to the nursing shortage of the 1980s, rotational 12-hour shifts have become the norm. Richardson started working straight nights about two years ago after rotating between day and night shifts for the first four years of her nursing career.
“It wasn’t my first choice as a new graduate, but now I prefer the pace.” She adds, “The night shift crew is usually more cohesive. We have to be.”
Clock Genes and Chronotypes
Are you a lark or an owl? Researchers at Vanderbilt University Medical Center (VUMC) in Nashville, TN, found that individual chronotypes (the normal time that organisms sleep and engage in their usual activities) make a difference to how people respond to shift work. As you might have guessed, larks are sun greeters whereas owls prefer the shadowy hours beyond twilight.
ONS member Nancy Wells, DNSc, RN, FAAN, director of nursing research at VUMC, worked with colleague and molecular biologist Carl Johnson, PhD, in a study looking at the effect of shift work on adaptation and overall health (Gamble et al., 2011).
“Dr. Johnson was interested in exploring the clock genes that regulate circadian rhythm,” Wells recalls. “Because patient safety depends on the night shift nurses’ alertness, and night shifts are typically scheduled for 12-hours, Dr. Johnson determined nurses were the ideal population to study.” Various clock genes have been identified, but CLOCK, PER1, and PER3 were the genes that Johnson’s research ultimately associated with health consequences—suggesting that genes and environment interact in both positive and negative ways.
Wells oversaw the collection of self-reported surveys and blood samples from 388 Vanderbilt nurses, about two-thirds of whom worked 12-hour night shifts.
“One of the most interesting study findings was the isolation of several variations in particular DNA sequences that were associated with poor sleep habits,” Wells says. “Much like genotype represents a person’s genetic makeup, and phenotype denotes the outward expression of inherent genes, the nurses’ self-reported chronotypes (morning lark or evening owl) closely matched their ability to adjust to switching between sleep routines.”
She uses an analogy of a car to describe how working outside of a nurse’s chronotype could be problematic. “When a vehicle is out of alignment, the chassis suffers abnormal wear and tear. Similarly, when a species’ instinctual 24-hour rhythm is interrupted, circadian misalignment occurs, which in turn can lead to negative health outcomes.”
Additionally, Wells said that the study found that nurses could adapt by adjusting their sleep behavior. “Of the five sleep strategies that were identified in the study, nurses who stayed awake for 12 hours before starting the night shift (no sleep method) had the poorest adaptation to fatigue and sleep regularity. Nurses who switched between cycles by either napping or using a strictly enforced schedule (switch sleepers) coped better with shift work.”
All in a Night’s Work
Richardson says she typically adjusts her sleep cycle for work. “I sleep three to four hours prior to a night shift, and if I don’t work the following night, I only sleep for four hours between shifts. If I am working two nights in a row, then I sleep for six to seven hours.”
Working only two nights a week is appealing to Richardson partly because she can spread the two nights apart. “I found that working a bunch of nights in a row just makes me crazy.”
According to Wells, “When compared with nurses who schedule sleep the day before starting a night shift rotation, nurses who used the no sleep method to maintain a daytime schedule when going into a series of night shifts had more disruption.” Study results also suggested variation in alcohol and caffeine consumption, wake time tiredness, and hours out of bed were closely associated with self-reported preferences for morning or evening wake time.
Self-Care for Shift Work
“Although several clock genes have been isolated, we still do not know precisely how they operate in shift workers,” Wells says. “Based on this research, I would recommend setting up routines when starting and finishing a run of nights particularly focusing on set sleep periods (e.g., several naps during the day you start nights and again when you come off nights).”
Richardson says that she uses several health-promoting and adaptation strategies. “I try to work out at least four times a week, and I especially like cycle/yoga classes because I feel like that combination kind of keeps the night shift flu-like feeling at bay. Also, I look at the day before a night shift as an accelerated day. I try to get as much done as possible before I sleep so I don’t feel like I’m losing days.”
She also recommends wearing compression socks or running calf sleeves because “everyone swells” and reminds fellow night shifters not to forget to hydrate during their shift.
“Shift work in nursing isn’t going away, and this particular study did not determine what type of shift work might be the healthiest in respect to providing night coverage,” Wells says. “What the study did show, however, was that nurses using the no sleep method reported less desirable outcomes than nurses adapting sleep times that more closely matched their natural body rhythms.”
Richardson’s advice is simple: “Figure out what sleep schedule works best for you.” And with a better understanding of the interplay of gene expressions and circadian rhythms, the figuring out part just might be a little easier.