ICU Patients Need Better Quality Sleep

Key Point

Although ICU patients appear to receive adequate amounts of sleep, their quality of sleep is poor.

The sleep patterns of patients in the ICU are so superficial that patients barely spend any time in the restorative stages of sleep that aid in healing, said researchers from the University of Texas Southwestern Medical Center in Dallas in the December 2007 Journal of Trauma: Injury, Infection, and Critical Care.

“Current clinical-care protocols routinely and severely deprive critically ill patients of sleep at a time when the need for adequate rest is perhaps most essential,” said Randall Friese, MD, Assistant Professor of Trauma, Burn, and Critical Care and lead author of the study.

FRAGMENTED SLEEP PATTERNS

“We haven’t recognized the importance of prescribing sleep,” said Dr. Friese, whose study is one of the first to examine the sleep patterns of surgical and trauma patients. “Patients in the ICU may look like they are sleeping, but they’re not sleeping well. They are not getting the restorative stages that are required.”

In their prospective observational study, Dr. Friese and colleagues monitored the sleep patterns of 16 patients in the ICU at Parkland Memorial Hospital in Dallas who had suffered traumatic injuries or had undergone intra-abdominal surgical procedures. The patients’ ages ranged from 20 to 83; 81.3% of patients were men, 62.5% were injured, and 31.3% were on mechanical ventilation. The patients had been in the ICU from two to 10 days. Patients with brain injuries were excluded from the study, because such injuries typically elicit abnormal sleep patterns.

The patients underwent continuous polysomnography for as long as 24 hours. Analysis was performed to detect differences in the proportion of time spent in the superficial stages 1 and 2 of sleep, the deep stages 3 and 4 of sleep, and REM sleep, compared with healthy historical controls.

The researchers found that the patients received an acceptable amount of sleep time (mean, 8.28 h) but that the sleep patterns were fragmented and significantly abnormal. Patients in the ICU spent 96% of their sleep cycle in stage 1 or 2 sleep versus normal sleep, in which as much as 50% is spent in the restorative deeper stages 3 and 4 and REM sleep.

PROVIDING AN ENVIRONMENT CONDUCIVE TO SLEEP

The next step, Dr. Friese said, is to design a clinical trial that makes the ICU environment more conducive to sleep and then monitor the patients’ outcomes. Some proposed steps to decrease disturbances in the ICU include adjusting monitoring machines so that alarms do not wake up sleeping patients, providing patients ear plugs and eye shields, dimming the lights, and using pharmacological sleeping aids.

“There are two major things contributing to abnormal sleep in these patients—the pathophysiology of the disease process itself and the stressful environment of the ICU,” Dr. Friese said. “If we can neutralize the stressful environment, maybe we can shorten the hospital stay, lower infection risks, and increase patient wound healing.”

Ramon Diaz-Arrastia, MD, PhD, Professor of Neurology and study coauthor, said the investigation demonstrated that “surgical patients in the ICU have essentially no restorative sleep.

“Restorative sleep is most abundant during the later part of sleep—it is sometime between 3 am to 6 am that the bulk of this stage of sleep occurs,” Dr. Diaz-Arrastia pointed out. “It is likely that with some straightforward measures, such as changing the schedule of nursing intervention, we may help these patients attain the restorative sleep that could improve their outcomes.”           

Suggested Reading
Friese RS, Diaz-Arrastia R, McBride D, et al. Quantity and quality of sleep in the surgical intensive care unit: are our patients sleeping? J Trauma Inj Infect Crit Care. 2007;63(6):1210-1214.

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