Rats that don't sleep don't just become brats, they become dead within four to five weeks. Studies demonstrate that sleep-deprived people have delayed reactions, difficulty concentrating, and impaired cognition and judgment. This explains using sleep-deprivation as an interrogation technique. So why is a nation so meticulous about children's sleep so careless about adults' rest?
A Centers for Disease Control and Prevention survey of 70,000 adults found that more than one-third of Americans don't get seven hours of sleep every night, the minimum amount they and the National Sleep Foundation recommend. (MMWR 2009;60:1; http://bit.ly/2dZ5sPU.)
Thirty-eight percent of the respondents even reported nodding off unintentionally during the day, five percent while driving. This suggests that data from the National Highway Traffic Safety Administration, that 100,000 motor vehicle crashes and 1,500 deaths are caused by driver fatigue each year, may be an underestimation.
EPs have personal experience with sleep-deprived driving, not to mention sleep-deprived patient interviewing, charting, and decision-making. Most emergency physicians I know have adapted to this dynamic; they still function at a high level despite circadian rhythm dysfunction and sleep deficit.
Most EPs are quite fastidious about their sleep hygiene and routines, and use common tricks of the trade: regular exercise, blackout curtains, white noise machines, hypnosis, and 4-7-8 breathing patterns. But this is not to say that we have it completely figured out. When you try to defy the normal sleep-wake cycle to provide 24/7 emergency care, it is an ongoing struggle for many docs to do right by their bodies, especially when they need to sleep during the day.
With all that said and new evidence on manipulating our pineal gland to minimize diurnal disruption, lets' take a less than exhausted — I mean, exhaustive — look at best practices and what's new with sleep research.
The exact physiological mechanism of sleep's restorative function has long been a mystery, but new evidence suggests that it may have to do with the upregulation of a glymphatic system that commingles cerebrospinal fluid and interstitial fluid. Xie and colleagues at the University of Rochester Medical Center proposed that sleep serves as a mechanism for removing toxic neuro byproducts (like B-amyloid and Aβoligomers) produced in the awake central nervous system. (Science 2013;342:373.) They found that sleeping and anesthetized mice had a cortical interstitial space expansion of more than 60 percent compared with those that were awake. It may be that baseline differences in individual sleep requirements are determined by the rate of neurotoxin creation during wakefulness and the degree of cortical interstitial expansion during sleep. We are pretty certain, at least for now, that an individual's sleep requirement is pretty set and unchangeable, especially in the long term. Most of us require at least seven hours every night.
Gregory Dean Jr. once said, “The two best physicians of them all [are] Dr. Laughter and Dr. Sleep.” We might have to throw Dr. Feelgood into the mix here, too. We are just beginning to understand the physiological functions of sleep, which include encoding memories via nerve-signal repetition; increased cellular production of proteins that are likely involved in repairing damages from stress, ultraviolet light, and dietary toxins; and spikes in growth-hormone release in young people. (MEDtube Sci 2015;3:35.)
What about employing Dr. Temazepam or Dr. Lorazepam? I suspect we've all been there, but what if there were a less sedating option. Calling Dr. Melatonin from the pineal gland. There was a time when melatonin supplementation seemed like a clever way to market placebos to long-distance travelers, but it is now recommended by the American Academy of Sleep Medicine to promote daytime sleep for night shift workers with shift work disorder. (Sleep 2007;30:1445; http://bit.ly/2dJGpVL.)
Sadeghniiat-Haghighi, et al., in the aptly titled journal Work, published a randomized study of refinery workers in Iran that tested the effect of 3 mg of melatonin taken 30 minutes prior to sleep in 50 workers with sleep difficulties. (2016;55:225.) They compared markers of sleep performance, recorded by a SOMNOwatch.
Only 39 participants finished the trial, and the researchers did not utilize polysomnography (the gold standard) for the assessment, but they did report two statistically significant differences: Melatonin administration was associated with increased sleep efficiency and decreased sleep latency versus baseline and placebo. This study builds on prior evidence that suggests melatonin may be safe (with low toxicity and low dependency profile) and reasonably effective when used to regulate sleep patterns in shift workers and perhaps in others such as those with hospital-induced insomnia.
Light as Therapy
Mike Tyson once gave this practical advice: “You can't stay married in a situation where you are afraid to go to sleep in case your wife might cut your throat.” The same advice might apply to the EP who tries to grab a catnap next to a psychotic meth-head on a 5150 hold. It also applies to any shift worker who attempts to sleep in the daytime without shutting and locking the door on natural light. I'm not the only one who has experienced an excruciatingly viscous night shift, during which I felt constantly on the verge of sleep, only to walk out into the early morning sun and immediately feel wide awake.
Some common approaches to mitigating the pesky effects of natural light on shift workers include attempting to flip the pancake on sleep patterns. Melatonin production by the pineal gland is regulated by the light/dark cycle, so it makes sense that the same effects may be achieved by carefully regulating exposure to light. This is why some EDs schedule their night shifts to end while it is still dark.
A detailed review by Emens and Burgess in Sleep Medicine Clinics is based on physiological profiles of melatonin subjects experiencing either circadian advance or delay within two or three or hours of habitual bedtime based on when they were exposed to bright light. (2015;10:435.) Those exposed to morning light just before the normal spike in melatonin levels before bedtime were shown to delay the circadian phase while those with early cycle light exposure were shown to advance the phase.
This means shift workers should strive to manipulate their light environment as much as possible. How about some BluBlocker glasses for the drive home when you get off at 7 a.m.? Wake up at 11 a.m. after a few hours, how about adjusting those blackout curtains? Wake up at 9 p.m. before the night shift, time to break out the natural light and reset your circadian phase.
Some vendors such as Verilux sell lights that approximate natural light. Look for something that provides an exposure to around 10,000 lux of light and minimal UV light.
The Mayo Clinic also recommends these guidelines for therapeutic use of natural light machines:
* Use within the first hour of waking.
* Use for about 20 to 30 minutes.
* Keep at a distance of about 16 to 24 inches from your face.
* Apply with eyes open but not looking directly at the light.
Share your best practices for shift work sleep with Dr. Ballard by emailing firstname.lastname@example.org.Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.