1. Honkus, Vicky L. MSN, RN


Sleep deprivation is a significant problem for patients in critical care units. Sleep is a complex, active process that is divided into 4 stages of non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep. Noise, lights, discomfort, pain, medications, and stress all contribute to a patient's inability to sleep. Lack of knowledge about the sleep stages, nursing routines, and frequent nursing assessment and interventions also impact the critically ill patient's ability to sleep. Education about sleep deprivation needs to be integrated into critical care courses and orientation programs. Sleep deprivation should be addressed on the multidisciplinary care plan and in health team conference, and nursing care planned accordingly. Sleep medications and their effects should be evaluated for each patient, as well as identifying medications that might be preventing or disturbing sleep.


Article Content

SLEEP is a basic need, much as food and water are for human survival. Sleep may not reach significance for an individual until it is lacking or disturbed. At that point, an individual may become short-tempered, irritable, overreactive, and unable to cope effectively with situations or people. Nurses who work in shifts and long hours know well the effects that lack of sleep can have on their attitudes and their ability to do their work. How much more of an impact then, can lack of sleep have on patients, particularly those in critical care units, who are already compromised by illness, surgery, wounds, or infection.


This article explores the sleep process, what impacts sleep for patients in critical care units, and suggests changes for nursing practice to promote sleep in these patients.


Sleep is a complex, active process that is programmed by man's circadian rhythm. This 24-hour biological clock is based on a daynight cycle, which programs humans to sleep at night and be awake during the day.1



Research has shown that there are 2 distinct categories of sleep, non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. NREM sleep is further subdivided into 4 stages, based on brain-wave activity, eye movements, and skeletal muscle movements in each stage. Sleep is objectively measured by polysomnography, which utilizes the electroencephalogram (EEG), the electromyelogram (EMG), and the electrooculogram (EOG).2


In a typical night an individual will progress through the 4 stages of NREM sleep, and return through the same stages, until reaching Stage 2. From Stage 2, sleep can either switch over to REM sleep, or progress again to Stages 3 and 4, and then return to Stage 2. The duration of each cycle varies with the time of night,3-7 with age,3,6,8,9 and with how sleepdeprived one might be.9,10


NREM sleep

Stage 1 of NREM sleep is always the first stage of the sleep process, whether the individual has just fallen asleep or whether he was awakened from a deeper stage of sleep and falls asleep again.10 In Stage 1, the individual may not even be aware that he has begun to sleep. Still aware of his surroundings, the individual is relaxed and drowsy, his thoughts are aimless and begin to drift, and thinking is less reality-oriented. The individual is less reactive to outside stimuli, but can still be aroused easily. Myoclonic jerks of the face, hands, or feet may occur at this time. Body temperature and vital signs start to drop as metabolism slows. Stage 1 is a brief stage, lasting no more than 7 minutes.2,7,9,11


Stage 2 of NREM sleep is a slightly deeper sleep and is a transition or "door" stage to deeper NREM stages or to REM sleep. The individual is no longer aware of his surroundings, and is a little harder to awaken. Fragments of dreams may occur, and eyes slowly roll from side to side. Metabolism and vital signs continue to decrease during this 15- to 20-minute stage. This is the most stable and predominant NREM sleep stage in adults, particularly later in the sleep period when the individual alternates between REM sleep and the NREM cycle.3,7,12


NREM Stage 3 sleep is much deeper than that of Stage 2, and the individual is now more difficult to arouse. Snoring may begin to occur because of decreased muscle tone. Vital signs, body temperature, and metabolism are decreased.7


Roughly 15 to 20 minutes after falling asleep, Stage 4 NREM sleep occurs. This is the deepest sleep stage, and the individual is very difficult to awaken.7 Sometimes referred to as "weary sleep,"it is at this time that sleep walking and bed-wetting can occur.12 The individual rarely moves at this time11 and vital signs and metabolism are at their lowest,7 with the parasympathetic system dominant.13,14 Factors such as advancing age, hypertension, congestive heart failure, and acute myocardial infarction may cause the sympathetic system to be dominant with respect to heart rate, particularly in response to physical and psychological stress.14


When people speak of having had a good night's sleep, it is likely primarily Stage 4 sleep that they are referring to. After a particularly exhausting day or physical activity, an individual often reports having had a good sound sleep because of an increased need for Stage 4 NREM sleep.4


NREM Stages 3 and 4 are the deepest stages of sleep and are often reported together as delta-wave sleep or slow-wave sleep (SWS), for the amplitude of waves seen on the EEG during these stages.2,7,9 This SWS constitutes 20% to 25% of sleep for the adult, but this percentage decreases with age. NREM Stage 4 sleep is the most sensitive to advancing age and begins decreasing after 20 years of age.3


Stage 4 is considered to be anabolic and restores one physically. During SWS, when metabolic activity is at its lowest, growth hormone is secreted, promoting protein synthesis and tissue healing. The lowered metabolic rate reduces oxygen consumption and promotes wound healing and tissue restoration.4,10,11,13,15


However, in the elderly, and in persons with acromegaly, hypothalamic disorders, and obesity, secretion of growth hormone during sleep is absent.7 After about 90 minutes, an individual has returned from Stage 4, back through Stage 3 to Stage 2. Instead of returning to Stage 1 and awakening, the individual may repeat the NREM cycle or progress to a brief episode of REM sleep.4,12


REM sleep

REM sleep is a very active stage with a high degree of cerebral and physiologic activity. REM sleep continues to facilitate protein anabolism, but during this same time there is great fluctuation in autonomic nervous system activity, causing heart rate variability. Increases in parasympathetic tone may cause bradycardia, sinus arrhythmia, and episodes of sinoatrial and atrioventricular node block. Sympathetic stimulation may cause transient increases in blood pressure, heart rate, respiratory rate, and cardiac output (resembling fright.) Oxygen consumption increases and the individual may have increased premature ventricular contractions and nocturnal angina during this stage.3,7,10-12,16


There is increased cerebral blood flow during REM sleep and research suggests that this stage involves memory storage and consolidation of learning. Although the brain is very active at this time, REM sleep is sometimes referred to as paradoxical sleep because of the inhibition of spinal motor neurons leading to muscle atonia (tonic REM), interspersed with bursts of rapid eye movement and distal muscle twitches (phasic REM).3,15,16 Large muscles are immobilized and the individual is unable to move.7,13 This stage is easily recognized by the rapid conjugate eye movements from side to side17 and the twitching of small facial muscles.7


Most dreams occur during REM sleep and are thought to be essential in the process of mental restoration and emotional healing.10,11,13 The day's events are reviewed and important information is categorized and integrated, helping to restore one mentally. Problem resolution or a new perspective may result from REM sleep,4,16 hence the phrase "I'll sleep on it." The EEG during REM sleep resembles that of a person who is awake but in deep concentration.12


Sleep studies reveal that everyone dreams during REM sleep. About 80% of people studied recalled their dreams when awakened from REM sleep. Only about 5% of people recalled their dreams when awakened from NREM sleep.7,9


REM sleep can last from 5 to 35 minutes with the smallest amount of REM sleep occurring during the early cycles of sleep and increasing with each full cycle during a night of sleep. NREM stages are most prominent during the early hours of sleep and decrease as REM increases in the later hours.3,4,10,11,17,18 An uninterrupted night of sleep for the adult consists of 4 to 6 successive sleep cycles, occurring every 90 minutes on the average.10,12,17


In the young adult, sleep consists of about 50% Stages 1 and 2 (mainly 2) and about 25% each of SWS (Stages 3 and 4) and REM sleep.17 In adults, REM sleep comprises about 20% of total sleep time, but decreases with advanced age.3,9


The elderly also experience much less SWS and more Stage 2 light sleep. The older person usually takes longer to fall asleep and awakens easily and more frequently.7,8,17 The elderly are more prone to nap during the day,8 which may further compromise the ability to sleep at night.


One factor that is constant no matter what age, is that when awakened from sleep, sleep always begins again at Stage 1, regardless of the stage one is awakened from.4,7,11 If awakened from sleep frequently, the individual may get little or no REM sleep.4



Patients in critical care units often experience a lack of sleep or frequent disruptions to their sleep, further compounding their illness. Psychological stress alone can temporarily affect an individual's sleep patterns. More time is spent trying to initiate sleep, and when sleep occurs, it mainly consists of lighter sleep in Stages 1 and 2.19


Research has shown that patients in critical care units may spend 40% to 50% of their sleep time awake, and of the remaining sleep time only 3% to 4% in REM sleep.2,7,20


Psychological stressors may cause an individual to need more REM sleep and may cause the individual to feel that they dreamed more than usual and had less restful sleep. Illness and hospitalization certainly increase psychological stress, but unfortunately hospitalization makes it less possible for the individual to obtain adequate REM sleep.4


Novaes and colleagues conducted a study to evaluate physical and psychological stressors in the intensive care unit (ICU) patients. Fifty patients were asked to complete the Intensive Care Unit Environmental Stressor Scale, ranking the 40 items from not stressful to very stressful. Of these 40 items, not being able to sleep was ranked as the second most important stressor, second only to pain.21



Sleep deprivation has been shown to induce a catabolic state and negatively affect the immune system and healing. There is decreased ability to resist and fight infection, further impacting the healing process and hospitalization.2,22,23 In addition to immunosuppression and decreased tissue repair, studies report decreased pain tolerance and profound fatigue of the sympathetic nerve centers. Normally, cortisol is released in the morning to help prepare the body for the day's stressors.24 Cortisol is also released during time of stress, and helps to reduce inflammation by causing stabilization of lysosomal membranes in damaged cells. Prolonged secretion of cortisol however, interferes with the body's ability to heal and fight infection because it can block the inflammation process, inhibit formation of connective tissue and granulation, and suppress antibody formation.10,25 Cortisol secretions are normally diminished during sleep and rise in the morning following circadian rhythms. Sleep deprivation in critical care patients prolongs cortisol secretion and results in decreased healing, making patients more susceptible to infection and a prolonged recovery process.10,24,25 Lack of sleep has also been shown to contribute to upper airway musculature dysfunction and blunting of hypercapneic and hypoxic ventilatory responsiveness, adversely affecting gas exchange. This could have a significant impact on patients with respiratory problems, particularly those who are being weaned from the ventilator or those who have just been extubated.26


Signs and symptoms of sleep deprivation

Nurses are very alert to signs and symptoms of potential or actual problems in their patients. The signs and symptoms of sleep deprivation may not be so apparent, at least initially. Behavioral changes such as restlessness and irritability may occur within 48 hours. Disorientation and slurred speech may precede psychotic behavior, which can occur within 96 hours.24


If a patient is deprived primarily of NREM sleep, he may experience fatigue, apathy, speech deterioration, poor judgment, and lack of energy. The nurse may observe ptosis and lack of facial expression. Deprivation of REM sleep may cause the patient to feel continually tired and have difficulty concentrating. When deprived of REM sleep for greater than 24 to 48 hours, the patient may experience irritability, confusion, poor impulse control, paranoia, and hallucination, or exhibit aggressive behavior.10,16,18,24


If an individual does not obtain enough sleep to meet his biological needs, this sleep debt will accumulate over time until the brain signals the body to obtain sleep.1 If sleep deprivation is prolonged, when the patient finally enters sleep, it consists of predominantly Stage 2 and the deep recovery sleep of Stage 4.10 REM sleep usually does not occur until the second or third night.9



Admission to a critical care unit negatively affects the patient's quantity and quality of sleep. Critically ill patients spend more time in the lighter stages of sleep, rather than the healing Stages 3 and 4 NREM, and REM sleep.24 Ironically the patients who need the most rest and sleep get the least. Reasons for this may include the noisy, unfamiliar environment, lighting, the patient's illness, pain, discomfort, anxiety, and stress.7,9,23,24



Environmental noise is due to a variety of causes, including ringing phones, talking, beepers, overhead speakers, and equipment sounds from suction apparatus and mechanical ventilation. Alarms from cardiac monitors, pulse oximeters, and ventilators add to the noise pollution. Particularly disturbing are ventilator alarms not being silenced while patients are being suctioned. Patients located near the nurses' station and storage rooms are often subjected to more noise and light.2


Olson reported that noise levels in critical care areas often exceed those levels recommended by the United States Environmental Protection Agency.23


Sound intensity is measured in decibels and researchers report that noise levels should be less than 35 to 40 dB for adequate rest15,27 and less than 53 dB during the day in critical care units.15 Noise in these areas has been found to range between 45 and 85 dB27 and averaged between 44 and 59 dB for the day shift, between 57 and 61 dB for the evening shift, and between 53 and 60 dB for the night shift.22 One study found that 35 dB was sufficient to arouse a patient from sleep, while another study reported that a 70-dB sound was most likely to awaken a sleeping person or move the subject to a lighter stage of sleep.22 Lee explains that the meaning of the noise may play a role in arousal from sleep, that a patient may awaken when their name is called, but not when the phone rings.7


All patients are affected in some way by sound, but elderly patients may be more easily disturbed by noise, because the majority of their sleep is of the lighter stages.7


Topf and Davis measured 10 REM sleep variables in 70 healthy female subjects who were randomly assigned to spend one night in a sleep laboratory under quiet conditions, or noise conditions (an audiotape of critical care unit sounds.) Results showed that the noiseconditioned subjects had less REM activity and shorter REM-period durations.5


Noise produces physiologic changes similar to what is seen in a generalized stress reaction, including vasoconstriction, elevated diastolic blood pressure, dilated pupils, and muscle tension. Because of adrenalin released by the sympathetic nervous system, these effects prevent the patient from relaxing and falling asleep.22



In addition to this sensory overload from noise, lighting has also been identified as a factor preventing sleep. The normal light/dark cycles help to regulate the biological clock and play an important role in maintaining wake-sleep cycles.7,27 Alterations in the light and dark cycles have a major influence on sleep patterns because of melatonin secretion and signaling the body's internal clock that it is time to sleep or be awake.7 Bright lights from the nurses' station, lights that are not dimmed, and lights that are turned on at night are all very disrupting to patients' sleep.7,12



General discomfort is another reason commonly given for inability to sleep. Patients often complain about the uncomfortable hospital beds, and the inability to get comfortable. Being attached to monitoring equipment, for example, prevents a patient from sleeping on his stomach, if that is his preferred sleeping position. The electrode pads used for monitoring sometime cause the skin to become irritated and itchy. Oxygen can be very drying to nasal passages if not humidified. Having intravenous central lines, and dressings can all be discomforting.


Room temperature or not having enough blankets may adversely affect sleep. During REM sleep, thermoregulation is absent and shivering or sweating cannot occur, and so individuals' body temperature is directly affected by their environment. When the environment is too cold or too hot, REM sleep will be decreased.7



Pain has been linked to the inability to sleep in several studies.19,21,27 In Novaes'study to evaluate physical and psychological stressors in the ICU, 50 patients were given the Critical Care Unit Environmental Stressor Scale and asked to rank the 40 items from not stressful to very stressful. Pain was ranked as the most stressful item on the scale by these intensive care unit patients.21 Patients in critical care units may have pain for a variety of medical and surgical reasons, and these patients are often subjected to medical procedures that are painful as well. It has been recommended that critical care nurses assume that their patients are in pain or at high risk for pain, and assess and treat accordingly.28



Medications that the patient is taking may disrupt his sleep as well. Beta blockers such as propranolol and metoprolol easily cross the blood-brain barrier and can cause disturbed sleep and nightmares. Metholdopa can also cause nightmares, although it increases REM sleep and decreases SWS. Diuretics can disturb sleep by increasing the need to void at night. Angiotensin-converting enzyme inhibitors and calcium channel blockers have also been shown to affect sleep.9 Other medications that may affect sleep include lithium, corticosteroids, antidepressants, theophylline, neuroleptics, anticonvulsants, and histamine blockers.9 Morphine, barbiturates, and analgesics reduce deep sleep and REM sleep, resulting in lighter sleep stages.15,24,29 ICU patients who are receiving continuous infusions of catecholamines to support blood pressure and cardiac output may have difficulty sleeping because of the stimulation of the reticular activating system.15



Psychological stressors may also be a reason for disturbed or insufficient sleep. When an individual is anxious or worried, it often takes longer to fall asleep,7 and the majority of sleep time is spent in the lighter stages of NREM 1 and 2. As the stressor diminishes or adaptation to the situation occurs, these effects on sleep disappear (see Box 1).

Box 1 - Click to enlarge in new window No caption available.

Sleep knowledge deficit

Nurses are excellent problem solvers, and are attuned to subtle changes in their patients' condition. Medical and nursing literature over the past 3 decades has included many excellent studies and informative articles describing why sleep deprivation in critical care units is a problem. Yet sleep deprivation remains an often overlooked aspect of the plan of care for these patients. In many critical care units, the patient's sleep is not addressed, nor is it even listed as a medical problem, although it has been shown to impact healing10,24,25 and may therefore lengthen hospital stay. Depending on the hospital and the unit, various factors may be responsible.


The topic of sleep deprivation is virtually nonexistent in critical care program curricula, and probably in many nursing and medical school programs. This most basic need that is common to every human being is not being taught to those who will administer and provide care for critically ill patients.


Nursing routines and interventions

In part, because of the lack of education about the sleep process and the physical and psychological benefits of sleep, hospital routines have been in place for years that disrupt and prevent sleep in critical care units. In order to have early morning laboratory work and test results available when physicians make rounds, most critical care units wake patients at 5 am or 6 am to draw blood and do electrocardiograms. In a study of 203 patients from 4 ICU's, patients were given a questionnaire on the day of discharge to evaluate their sleep during their stay in the ICU. The questions assessed perceived sleep quality and daytime sleepiness, perceived sleep disruption caused by environmental activities, and perceived sleep disruption caused by specific environmental noises. Friedman found that nursing interventions such as checking of vital signs and phlebotomy were more disruptive to sleep than were other factors such as noise and light.28 Since the patient has been wakened, the nurse will often do a quick reassessment and check vital signs. Often times the more critical patients are bathed and bed linen changed on night shift to allow the day shift more time for procedures, tests, and physician and family visits.2 This practice interferes primarily with a patient's REM sleep, since the majority of REM sleep occurs during the latter half of the night.7


One study reported that nurses generally agreed that sleep was important to their patients, but found it difficult to organize their assessment routines and tasks to even accommodate 2-hour periods of quiet time.23 The role of critical care nurses and the acuity of their patients often cause them to focus on various tasks, procedures, and assessment routines, with little thought or significance given to patient sleep.


When nurses were interviewed, they felt their patients' sleep was interrupted very little. However, when they actually kept a record of the times they interrupted their patients' sleep, they were amazed and determined to make some changes in the plan of care. Krachman describes a study in which 9 postoperative patients were monitored by continuous EEG within 2 hours of surgery until discharge from the ICU, or for a maximum of 83 hours. The total sleep time was severely decreased, with 5 patients not sleeping at all during the initial 24 hours postoperatively; the SWS was abolished and REM sleep was severely reduced. Sleep time was grossly overestimated by the nursing staff (7 hours), when compared with the polygraph recording 2.5 hours in a subgroup of 6 patients who had both done simultaneously.15


Patient satisfaction is a major focus for hospitals today, in this competitive medical market. Doering and fellow researchers collected data from 89 discharged cardiac surgical patients via telephone interviews based on 4 major themes: being satisfied (with care), not being cared for, physical needs unmet, and informational needs unmet. One patient responded with mixed satisfaction and areas for improvement, stating "I was very impressed (with care), but I needed more rest."30 With regard to physical needs unmet, statements included "I was awakened too often for medication and routine things," and "I did not feel I had enough rest in the hospital. Something should be done to improve patients' ability to rest and sleep."30



Education is key to changing nursing priorities and practice. The sleep process and effects of deprivation need to be incorporated into critical care education programs and continuing education programs, and encouraged as nursing research topics.


Sleep requirements need to become part of the written multidisciplinary plan of care, to allow for care and assessment of patients, but incorporating blocks of uninterrupted sleep. It needs to be discussed in shift to shift report, and may need to be discussed in Health Team Conference. Nursing activities should be organized to make sleep a priority for patients in critical care units.


In one hospital, staff recognized that sleep deprivation was an issue in their Medical Intensive Care Unit, and developed a sleep protocol in coordination with their medical director, staff pharmacist, and Respiratory Therapy Department. The goal was to allow an uninterrupted 4-hour block of time between 1 am and 5 AM for selected patients, while continuing to assess the patient visually and with monitoring parameters. A learning curve was required, as the staff had to become comfortable with approaching physicians and other health care team members about the protocol. However, the nurses began to appreciate their responsibility in directing the care of their patients and making a change in practice.13


Planning for effective sleep should begin as early as possible in the critical care unit. Asking the patient about his usual sleep times and patterns, and what helps him sleep at home, will assist the nurse to design a plan for her patient. Ask the patient if he would like his family bring in his pillow from home.


If the patient has a tendency to nap during the day, morning naps should be encouraged rather than afternoon naps because afternoon naps consist mostly of deep sleep (Stage 4) and short periods generally leave the patient feeling groggy. Morning naps, however, are mostly a continuation of REM sleep. Also, if a patient naps in the morning, he might feel tired enough by evening to fall asleep.4,12 Patients with brain injuries may benefit more from the healing effects of REM sleep in the mornings, whereas patients with severe physical trauma may benefit more from afternoon naps.10


Preparing the patient for sleep

If the patient has a pulmonary artery and/or arterial line, make sure the transducer is leveled to right atrium with the patient's head of the bed in the desired position. Leveling the transducer at the phlebostatic axis, with the patient in position for sleep, will assure that the assessment readings taken throughout the night are accurate to guide decision-making. Assess the patient and the intravenous lines for patency.


Assess the patient for any pain or discomfort. If pain medication is required, try to give it early enough so that it takes effect before bedtime and the patient will be pain-free and more relaxed. If sleep medication is ordered, offer it only after pain is relieved, so that the hypnotic will be more effective.12


Offering a bedtime snack or a glass of warm milk may encourage sleep. Nursing activities such as freshening the bed linen and allowing the patient to brush his teeth, wash his face, and void before sleep are helpful. Providing an extra pillow or blanket, arranging the pillows in a certain way, and assisting the patient to a comfortable position for sleeping may be helpful. A back massage can be very relaxing and therapeutic, and provides the patient with his nurse's undivided attention for the moment. Touch can be very therapeutic, and may provide an opportunity for the patient to ask questions or share concerns that might not otherwise have been verbalized.


Richards tested the effect of a back massage and combination of muscle relaxation, mental imagery, and music on the sleep of 69 older men with a cardiovascular illness who were hospitalized in a critical care unit. Her study showed significant differences between the back-massage and the control group, in the percentage of Stage 2 and REM sleep, with the back-massage group sleeping longer than the control group.6


When giving a hypnotic, make that the final trip to the patient's room for the shift. Before leaving, make sure the patient has fresh water, and that the call light is within reach. Make sure the intermittent suction machine is turned off, the oxygen tubing is free of water, faucets are not dripping, and the urinal is empty and within reach. Pull the patient's curtain closed to help block out light from the unit. If there is a door to the room, close it somewhat to block out noise.11 Dim the hallway and nursing station lights and turn unnecessary lights out.


During the night, take note of any patient who appears not to be sleeping. Tossing and turning and wakefulness can often be detected on the monitor by movement. By checking on the patient, you may find that he is having pain, is anxious, or in some distress that warrants further assessment.


If it is necessary to assess the patient, perform procedures during the night, or bathe the patient, do so as quietly as possible. Since critically ill patients sometimes cannot tolerate a lot of activity at one time, try to space procedures to allow a minimum of 2 hours of uninterrupted sleep at a time.


If you must awaken a patient, first observe to see if he is in REM sleep. If possible, wait until that stage ends before waking him since REM sleep is usually brief.4,11


Noise and interruptions should be kept to a minimum, to allow the patient to obtain the much needed NREM Stages 3 and 4 sleep and REM sleep.



If hypnotics are indicated, it is wise to first evaluate the medications that the patient is receiving, to make certain that none of them are contributing to the patient's inability to sleep.31 Consulting with the pharmacist may help identify these medications so that discussion can be initiated with the physician.


Benzodiazepines have traditionally been used over the past several years to promote sleep. The 5 drugs in this class that are approved as hypnotics are listed in Table 1. These drugs have a general tendency to decrease sleep latency and the number of awakenings, but vary significantly as to onset of action, half-life, and active metabolites. Although all 5 drugs in this class increase Stage 2 sleep, they also shorten REM sleep, and most shorten SWS.15 However, by decreasing the time required to fall asleep and the number of awakenings, they increase the total sleep time.29 The drugs in this class have a wide variation in rate of onset and elimination times, and in some patients can cause a rebound effect of increased daytime anxiety.7

Table 1 - Click to enlarge in new window Drugs commonly used to induce sleep

Zaleplon and zolpidem are nonbenzodiazepine hypnotics and have a similar action to that of benzodiazepines, but have the advantage of increasing NREM Stages 3 and 4 SWS.29,31



Much education needs to be done with respect to sleep in critical care units, and the effects of sleep deprivation on that patient population. Changing practice requires education and support at many levels, and from various disciplines. Nurses are patient advocates and need to identify issues within their own critical care units that are preventing effective sleep in their patients. Once the situation has been assessed, they need to devise a plan to provide periods of uninterrupted sleep, involving appropriate members of the health care team. Implementation and progress may be slow, but evaluation will likely prove beneficial with improved healing, decreased length of stay, and decreased hospital costs, and may improve patient satisfaction.




1. Elliott A. Primary care assessment and management of sleep disorders. J Am Acad Nurse Pract. 2001;13:409-420. [Context Link]


2. Culpepper Richards K. Sleep in the ICU: a description of night sleep patterns in the critical care unit. Heart Lung. 1988;17:35-42. [Context Link]


3. Landis C. Arrhythmias and sleep pattern disturbances in cardiac patients. Prog Cardiovasc Nurs. 1988;3:73-80. [Context Link]


4. Hayter J. The rhythm of sleep. Am J Nurs. March 1980;3:457-461. [Context Link]


5. Topf M, Davis J. Critical care unit noise and rapid eye movement (REM) sleep. Heart Lung. 1993;22:252-258. [Context Link]


6. Culpepper Richards K. Effect of a back massage and relaxation intervention on sleep in critically ill patients. Am J Crit Care. 1998;7:288-298. [Context Link]


7. Lee K. An overview of sleep and common sleep problems. Am Nephrol Nurses' Assoc. 1997;24:614-677. [Context Link]


8. Avidan A. Sleep changes and disorders in the elderly patient. Curr Neurol Neurosc Rep. 2002;2:178-185. [Context Link]


9. Parker K. Promoting sleep and rest in critically ill patients. Crit Care Nurs Clin North Am. 1995;7:337-349. [Context Link]


10. Evans J, French D. Sleep and healing in intensive care settings. Dimens Crit Care Nurs. 1995;14:189-199. [Context Link]


11. Lukasiewicz-Ferland P. When your ICU patient can't sleep. Nursing. 1987;17:51-53. [Context Link]


12. Grant D, Klell C. For goodness sake-let your patients sleep! Nursing. 1974;4:54-57. [Context Link]


13. Edwards G, Schuring L. Sleep protocol: a research-based practice change. Crit Care Nurse. April 1993;13:84-88. [Context Link]


14. Culpepper Richards K. Sleep promotion. Crit Care Nurs Clin North Am. 1996;8:39-51. [Context Link]


15. Krachman S, D'Alonzo G, Criner G. Sleep in the intensive care unit. Chest. 1995;107:1713-1719. [Context Link]


16. Chuman M. The neurological basis of sleep. Heart Lung. 1983;12:177-181. [Context Link]


17. Lader J. Therapeutic focus: management of insomnia. Br J Clin Pract. 1990;44:125-130. [Context Link]


18. Littrell K, Schumann L. Promoting sleep for the patient with a myocardial infarction. Crit Care Nurse. 1989;9:44-49. [Context Link]


19. Reid E. Factors affecting how patients sleep in the hospital environment. Br J Nurs. 2001;10:913-915. [Context Link]


20. Deamer R, Scharf M, Kales A. Sleep patterns in the coronary care unit. US Navy Med. 1972;59:19-23. [Context Link]


21. Novaes M, Aronovich A, Ferraz M, Knobel E. Stressors in ICU: patients' evaluation. Intensive Care Med. 1997;23:1282-1285. [Context Link]


22. Snyder-Halpern R. The effect of critical care unit noise on patient sleep cycles. Crit Care Q. 1985;7:41-51. [Context Link]


23. Olson D, Borel C, Laskowitz D, Moore D, McConnell E. Quiet time: a nursing intervention to promote sleep in neurocritical care units. Am J Crit Care. 2001;10:74-78. [Context Link]


24. Dines-Kalinowski C. Nature's nurse: promoting sleep in the ICU. Dimens Crit Care Nurs. 2002;21:32-34. [Context Link]


25. DeVillier B. Physiology of stress: cellular healing. Crit Care Q. March 1984;15-19. [Context Link]


26. Eveloff S. The disruptive ICU: an issue to lose sleep over? Chest. 1995;107:1483-1484. [Context Link]


27. Baker C. Sensory overload and noise in the ICU: sources of environmental stress. Crit Care Q. 1984;6: 66-79. [Context Link]


28. Freedman N, Kotzer N, Schwab R. Patient perception of sleep quality and etiology of sleep disruption in the intensive care unit. Am J Respir Crit Care Med. 1999;159:1155-1999. [Context Link]


29. Long S. Review of prescription therapy for insomnia. Drug Top. October 2002;86-95. [Context Link]


30. Doering L, McGuire A, Rourke D. Recovering from cardiac surgery: what patients want you to know. Am J Crit Care. 2002;11:333-343. [Context Link]


31. Weitzel K, Buie B, Barnes S. Treatment of insomnia in the elderly. Drug Top. January 2003;55-64. [Context Link]

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Sleep Deprivation in Critical Care Units




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Provider Accreditation:


This Continuing Nursing Education (CNE) activity for 1.5 contact hours is provided by Lippincott Williams & Wilkins, which is accredited as a provider of continuing education in nursing by the American Nurses Credentialing Center's Commission on Accreditation and by the American Association of Critical-Care Nurses (AACN 9722, CERP Category A). This activity is also provider approved by the California Board of Registered Nursing, Provider Number CEP 11749 for 1.5 contact hours. LWW is also an approved provider of CNE in Alabama, Florida, and Iowa and holds the following provider numbers: AI, #ABNP0114, FL, #FBN2454, IA #75. All of its home study activities are classified for Texas nursing continuing education requirements as Type 1.


Your certificate is valid in all states. This means that your certificate of earned contact hours is valid no matter where you live.


Payment and Discounts:


* The registration fee for this test is $12.95.


* If you take two or more tests in any nursing journal published by LWW and send in your CE enrollment forms together, you may deduct $0.75 from the price of each test.


* We offer special discounts for as few as six tests and institutional bulk discounts for multiple tests. Call (800) 933-6525 x331 or x332, ext. 1286 for more information.




General Purpose: To explore the sleep process, how it is altered for patients in critical care units, and how to adjust nursing practice to promote sleep in these patients.


Learning Objectives: After reading this article and taking this test, you will be able to:


1. List at least three key factors helpful for understanding normal sleep patterns and cycles.


2. Discuss the physiological effects of normal and abnormal sleep patterns.


3. Outline appropriate sleep-promoting interventions for critical care patients.





1. From which pivotal stage of non-REM sleep does an individual progress to either REM sleep or return for additional non-REM sleep?


a. stage 1.


b. stage 2.


c. stage 3.


d. stage 4.



2. How long each sleep cycle lasts varies with


a. age.


b. gender.


c. metabolism.


d. circadian rhythm.



3. Bed wetting is most likely to occur during which stage of non-REM sleep?


a. stage 1


b. stage 2


c. stage 3


d. stage 4



4. Myoclonic jerks are common during which stage of non-REM sleep?


a. stage 1


b. stage 2


c. stage 3


d. stage 4



5. Slow-wave sleep


a. refers to stages 2 and 3 of non-REM sleep.


b. promotes wound healing and tissue restoration.


c. is the most stable sleep period in adults.


d. accounts for about 40% of the average adult's sleep time.



6. During REM sleep


a. blood pressure drops.


b. oxygen consumption decreases.


c. large muscle movement increases.


d. cardiac output increases.



7. Electroencephalogram readings taken during REM sleep are similar to those of a person who is


a. in a deep stage of non-REM sleep.


b. concentrating intensely.


c. extremely active physically.


d. drowsy but trying to stay awake.



8. Most adults


a. remember their dreams when they are awakened from REM sleep.


b. have between six and eight sleep cycles per night.


c. have REM sleep periods lasting from 40 to 60 minutes.


d. have REM sleep periods beginning about an hour apart.



9. For patients in critical care units, how much of their sleep time is actually REM sleep?


a. 3% to 4%


b. 5% to 15%


c. 20% to 30%


d. 40% to 50%



10. Sleep deprivation


a. reduces cortisol production.


b. suppresses the immune system.


c. stimulates sympathetic nerve centers.


d. improves pain tolerance.



11. A sign of prolonged REM sleep deprivation is


a. speech deterioration.


b. ptosis.


c. lack of facial expression.


d. paranoia.



12. In the study by Novaes et al. (1997), which sleep-preventing stressor was rated as the most stressful by critical care patients?


a. noise


b. bright lights


c. pain


d. environmental temperature



13. Which medication is most likely to increase REM sleep?


a. propranolol


b. morphine


c. flurazepam


d. methyldopa



14. When planning interventions for a critical care patient who normally takes a daily nap at home, encourage the patient


a. to take a morning nap.


b. to take an afternoon nap.


c. to nap at his customary naptime.


d. not to nap while hospitalized.



15. To help prepare a critical care patient for sleep, administer


a. analgesics just before sleep.


b. hypnotics before analgesics.


c. hypnotics and analgesics at the same time.


d. hypnotics only after pain is controlled.

CE Enrollment Form


Key words:: discomfort; hypnotics; interruptions; noise; NREM sleep; pain; REM sleep; sleep; sleep deprivation; stress