Unit 13 Sleep

hypnotics

Class of drug that causes insensibility to pain and induces sleep.

Sleep History.

Includes recent changes in sleep pattern, sleep symptoms experienced during waking hours, use of sleep and other prescribed or over-the-counter medications, diet and intake of substances such as caffeine or alcohol that influence sleep, and recent life events that have affected the patient's mental and emotional status.

Pharmacological Approaches: Restorative Care

Long-term use of antianxiety, sedative, or hypnotic agents disrupts sleep and leads to more serious problems. Benzodiazepines and benzodiazepine-like drugs are common classifications of drugs used to treat sleep problems. The benzodiazepine-like drugs have become the treatment of choice for insomnia because of improved efficacy and safety of use . These medications are contraindicated in infants less than 6 months. Pregnant patients need to avoid them because their use is associated with risk of congenital anomalies.

Health Promotion.

Patients benefit most from instructions based on information about their homes and lifestyles such as which type of activities promote sleep in a night-shift worker or how to make the home environment more conducive to sleep. They will more likely apply information that is useful and valued.

nonrapid eye movement (NREM) sleep

Sleep that occurs during the first four stages of normal sleep.

Usual Sleep Patterns.

Sleepiness becomes pathological when it occurs at times when individuals need or want to be awake. Chronic lack of sleep is much more serious and causes serious alterations in the ability to perform daily functions.

Drugs and Substances.

Sleepiness, insomnia, and fatigue often result as a direct effect of commonly prescribed medications (Box 43-4). Medications prescribed for sleep often cause more problems than benefits.

rapid eye movement (REM) sleep

Stage of sleep in which dreaming and rapid eye movements are prominent; important for mental restoration.

sleep

State marked by reduced consciousness, diminished activity of the skeletal muscles, and depressed metabolism.

Narcolepsy

Syndrome involving sudden sleep attacks that a person cannot inhibit. Uncontrollable desire to sleep may occur several times during a day.

Middle Adults.

The amount of stage 4 sleep begins to fall, a decline that continues with advancing age. Insomnia is particularly common, probably because of the changes and stresses of middle age. Women experiencing menopausal symptoms often experience insomnia.

Dreams

The dreams of REM sleep are more vivid and elaborate; and some believe that they are functionally important to learning, memory processing, and adaptation to stress. The ability to describe a dream and interpret its significance sometimes helps resolve personal concerns or fears. People who recall dreams vividly usually awake just after a period of REM sleep.

Neonates.

The neonate up to the age of 3 months averages about 16 hours of sleep a day. The sleep cycle is generally 40 to 50 minutes with wakening occurring after one to two sleep cycles. Approximately 50% of this sleep is REM sleep, which stimulates the higher brain centers.

Parasomnia

The parasomnias are sleep problems that are more common in children than adults. Because of an association between the prone position and the occurrence of SIDS, the American Academy of Pediatrics recommends that parents place apparently healthy infants in the supine position during sleep. Parasomnias that occur among older children include somnambulism (sleepwalking), night terrors, nightmares, nocturnal enuresis (bed-wetting), body rocking, and bruxism (teeth grinding). When adults have these problems, it often indicates more serious disorders.

Circadian Rhythms/Biological Clock

The suprachiasmatic nucleus (SCN) nerve cells in the hypothalamus control the rhythm of the sleep-wake cycle and coordinate this cycle with other circadian rhythms. The predictable changing of body temperature, heart rate, blood pressure, hormone secretion, sensory acuity, and mood depend on the maintenance of the 24-hour circadian cycle. Reversals in the sleep-wake cycle, such as when a person who is normally awake during the day falls asleep during the day, often indicate a serious illness. Normally body temperature peaks in the afternoon, decreases gradually, and drops sharply after a person falls asleep.

Emotional and Mental Status

When a sleep disturbance is related to an emotional problem, the key is to treat the primary problem; its resolution often improves sleep. Patients with mental illnesses may need mild sedation for adequate rest.

Patient Outcomes.

When outcomes are not met, ask questions such as: • Are you able to fall asleep within 20 minutes of getting in bed? • Describe how well you sleep when you exercise. • Does the use of quiet music at bedtime help you to relax? • Do you feel rested when you wake up?

Setting Priorities.

When physical symptoms are interfering with sleep, managing the symptoms is your first priority. After symptoms are relieved, focus on sleep therapies.

Emotional Stress.

Worry over personal problems or a situation frequently disrupts sleep. Older patients frequently experience losses that lead to emotional stress such as retirement, physical impairment, or the death of a loved one.

Sleep apnea

a disorder characterized by the lack of airflow through the nose and mouth for periods of 10 seconds or longer during sleep. There are three types of sleep apnea: central, obstructive, and mixed apnea.

hypersomnolence

characterized by recurrent episodes of excessive daytime sleepiness or prolonged nighttime sleep

Sedatives

medications that produce a calming or soothing effect

Nursing Diagnoses

• Anxiety • Ineffective Breathing Pattern • Acute Confusion • Ineffective Coping • Insomnia • Fatigue • Disturbed Sleep Pattern • Sleep Deprivation • Readiness for Enhanced Sleep

Classification of Select Sleep Disorders

Hypersomnias are sleep disturbances that result in daytime sleepiness and are not caused by disturbed sleep or alterations in circadian rhythms. The parasomnias are undesirable behaviors that occur usually during sleep. In sleep-related movement disorders the person experiences simple stereotyped movements that disturb sleep.

Promoting Comfort.

Instruct patients to wear loose-fitting nightwear. Help adjust medication schedules, instruct patients to regularly void before rest periods, and suggest silencing the telephone ringer.

cataplexy

Condition characterized by sudden muscular weakness and loss of muscle tone; sudden muscle weakness during intense emotions such as anger, sadness, or laughter, occurs at any time during the day

Sleep deprivation

Condition resulting from a decrease in the amount, quality, and consistency of sleep.

Behaviors of Sleep Deprivation.

Observe for behaviors such as irritability, disorientation (similar to a drunken state), frequent yawning, and slurred speech. If sleep deprivation has lasted a long time, psychotic behavior such as delusions and paranoia sometimes develop. For example, a patient reports seeing strange objects or colors in the room, or he or she acts afraid when the nurse enters the room.

Promoting Safety.

A small night-light helps a patient orient to the room environment before going to the bathroom. Beds set lower to the floor can lessen the chance of a person falling. Instruct patients to remove clutter and throw rugs from the path used to walk from the bed to the bathroom. Do not startle sleepwalkers but instead gently wake them and lead them back to bed. To reduce the chance of suffocation, do not place pillows, stuffed toys, or the ends of loose blankets in cribs. Parents need to place an infant on his or her back to prevent suffocation.

Promoting Comfort: Restorative Care

A warm bath or shower before bedtime is relaxing. Offer patients restricted to bed the opportunity to void and wash their face and hands. Toothbrushing and care of dentures also help to prepare patients for sleep. Position patients to support their dependent body parts and protect pressure points. Offer a back or hand massage to aid in muscle relaxation just before a patient goes to sleep.

diurnal/circadian rhythm

Repetition of certain physiological phenomena within a 24-hour cycle.

School-Age Children.

A 6-year-old averages 11 to 12 hours of sleep nightly, whereas an 11-year-old sleeps about 9 to 10 hours. The 6- or 7-year-old usually goes to bed with some encouragement or by doing quiet activities. The older child often resists sleeping because he or she is unaware of fatigue or has a need to be independent.

Promoting Bedtime Routines.

A bedtime routine (e.g., same hour for bedtime, snack, or quiet activity) used consistently helps young children avoid delaying sleep. Relaxation exercises such as slow, deep breathing for 1 or 2 minutes relieve tension and prepare the body for rest. Guided imagery and praying also promote sleep for some patients. The bedroom is not a place to work, and patients need to always associate it with sleep.

Bedtime Snacks.

A dairy product such as warm milk or cocoa that contains L-tryptophan is often helpful in promoting sleep. A full meal before bedtime often causes gastrointestinal upset or reflux and interferes with the ability to fall asleep. Warn patients against drinking or eating foods with caffeine before bedtime. Coffee, tea, colas, and chocolate act as stimulants and diuretic, causing a person to stay awake or to awaken throughout the night.

Exercise and Fatigue.

A person who is moderately fatigued usually achieves restful sleep, especially if the fatigue is the result of enjoyable work or exercise. Exercising 2 hours or more before bedtime allows the body to cool down and maintain a state of fatigue that promotes relaxation. However, excess fatigue resulting from exhausting or stressful work makes falling asleep difficult.

Sleep Disorders

Sleep disorders are conditions that, if untreated, generally cause disturbed nighttime sleep that results in one of three problems: insomnia, abnormal movements or sensation during sleep or when waking up at night, or excessive daytime sleepiness (EDS). Insomnia disorders are related to difficulty falling asleep, frequently awaking from sleep, short periods of sleep, or sleep that is nonrestorative.

Environmental Controls.

All patients require a sleeping environment with a comfortable room temperature and proper ventilation, minimal sources of noise, a comfortable bed, and proper lighting. Instruct parents to place the infant on a firm mattress that is covered by a fitted sheet that meets current safety standards; to clothe the baby in a sleeper for warmth; to not place pillows, quilts, toys, or anything in the crib; and to position the crib away from open windows or drafts. Older adults often require extra blankets or covers. Eliminate distracting noise. It is also important to remember that some patients sleep with familiar inside noises such as the hum of a fan. Commercial products that produce a soothing noise such as ocean waves or rainfall create a soothing environment for sleep. Light should not shine directly on their eyes. For older adults light reduces the chance of confusion and prevents falls when walking to the bathroom.

Description of Sleeping Problems.

As an adjunct to the sleep history, have the patient and bed partner keep a sleep-wake log for 1 to 4 weeks.

Usual Sleep Pattern.

Ask the following questions to determine a patient's sleep pattern: 1. What time do you usually get in bed each night? 2. How much time does it usually take to fall asleep? Do you do anything special to help you fall asleep? 3. How many times do you wake up during the night? Why? 4. What time do you typically wake up in the morning? 5. On average, how many hours do you sleep each night?

Bedtime Routines.

Assess habits that are beneficial compared with those that disturb sleep. Pay special attention to a child's bedtime rituals.

Management of Narcolepsy

Brief daytime naps no longer than 20 minutes help reduce subjective feelings of sleepiness. Other management methods that help are following a regular exercise program, practicing good sleep habits, avoiding shifts in sleep, strategically timing daytime naps if possible, eating light meals high in protein, practicing deep breathing, chewing gum, and taking vitamins. Patients with narcolepsy need to avoid factors that increase drowsiness (e.g., alcohol; heavy meals; exhausting activities; long-distance driving; and long periods of sitting in hot, stuffy rooms).

Toddlers.

By the age of 2 children usually sleep through the night and take daily naps. Total sleep averages 12 hours a day. The percentage of REM sleep continues to fall. Often give up daytime naps.

Sleep Deprivation.

Causes include symptoms (e.g., fever, difficulty breathing, or pain) caused by illnesses, emotional stress, medications, environmental disturbances (e.g., frequent nursing care), and variability in the timing of sleep because of shift work. Chronic sleep deprivation is associated with development of cardiovascular disease, weight gain, type II diabetes, poor memory, depression, and digestive problems. Constant environmental stimuli within the ICU such as strange noises from equipment, the frequent monitoring and care given by nurses, and ever-present lights confuse patients.

Environmental Controls: Acute Care

Close the curtains between patients in semiprivate rooms. Dim lights on a hospital nursing unit at night. Conduct conversations and reports in a private area away from patient rooms and keep necessary conversations to a minimum, especially at night.

Older Adults.

Complaints of sleeping difficulties increase with age. Episodes of REM sleep tend to shorten. Stages 3 and 4 NREM sleep progressively decrease; some older adults have almost no stage 4, or deep sleep. An older adult awakens more often during the night, and it takes more time for him or her to fall asleep. The tendency to nap seems to increase . The presence of chronic illness often results in sleep disturbances for the older adult.

biological clock

Cyclical nature of body function. Functions controlled from within the body are synchronized with environmental factors; same meaning as biorhythm.

Physical and Psychological Illness

Determine whether the patient has any preexisting health problems that interfere with sleep. If the patient has recently had surgery, expect him or her to experience some sleep disturbance.

Establishing Periods of Rest and Sleep.

Do this by scheduling assessments, treatments, procedures, and routines for times when patients are awake. Do not give baths and routine hygiene measures during the night for nursing convenience. Unless maintaining the therapeutic blood level of a drug is essential, give medications during waking hours. Always try to provide the patient with 2 to 3 hours of uninterrupted sleep during the night. A nurse instructs assistive personnel in the coordination of patient care to reduce patient disturbances. This means planning activities so the patient has as long as an hour or more to rest quietly rather than having a nurse or other personnel return to the room every few minutes.

Narcolepsy.

During the day a person suddenly feels an overwhelming wave of sleepiness and falls asleep; REM sleep occurs within 15 minutes of falling asleep. A person with narcolepsy often has vivid dreams . Sleep paralysis, or the feeling of being unable to move or talk just before waking or falling asleep, is another symptom. Narcoleptic patients are treated with stimulants or wakefulness-promoting agents such as sodium oxybate, modafinil (Provigil) or armodafinil (Nuvigil) that only partially increase wakefulness and reduce sleep attacks. Patients also receive antidepressant medications that suppress cataplexy and the other REM-related symptoms.

Excessive daytime sleepiness (EDS)

EDS often results in impaired waking function, poor work or school performance, accidents while driving or using equipment, and behavioral or emotional problems.

Reducing Stress

Encourage a patient who has difficulty falling asleep to get up and pursue a relaxing activity such as sewing or reading rather than staying in bed and thinking about sleep. Cultural tradition causes families to approach sleep practices differently (Box 43-10).

Food and Caloric Intake.

Following good eating habits is important for proper sleep. Eating a large, heavy, and/or spicy meal at night often results in indigestion that interferes with sleep. Caffeine, alcohol, and nicotine consumed in the evening produce insomnia. Coffee, tea, cola, and chocolate contain caffeine and xanthines that cause sleeplessness. Weight gain contributes to OSA because of increased size of the soft tissue structures in the upper airway. Weight loss causes insomnia and decreased amounts of sleep.

Goals and Outcomes

Goal: The patient will control environmental sources disrupting sleep within 1 month. Outcomes: • Patient identifies factors in the immediate home environment that disrupt sleep in 2 weeks. • Patient reports having a discussion with family members about environmental barriers to sleep in 2 weeks. • Patient reports changes made in the bedroom to promote sleep within 4 weeks. • Patient reports having fewer than two awakenings per night within 4 weeks.

Environment.

Good ventilation is essential for restful sleep. The size, firmness, and position of the bed affect the quality of sleep. Noise in hospitals is usually new or strange and often loud. Thus patients wake easily. Noise causes increased agitation; delayed healing; impaired immune function; and increased blood pressure, heart rate, and stress. Light levels affect the ability to fall asleep. Some patients prefer a dark room, whereas others such as children or older adults prefer keeping a soft light on during sleep. Patients also have trouble sleeping because of the room temperature.

Sleep and Rest

Illness and unfamiliar health care routines easily affect the usual rest and sleep patterns of people entering a hospital or other health care facility.

Infants.

Infants usually develop a nighttime pattern of sleep by 3 months. The infant normally takes several naps during the day but usually sleeps an average of 8 to 10 hours during the night for a total daily sleep time of 15 hours. About 30% of sleep time is in the REM.

Insomnia.

Insomnia is a symptom that patients experience when they have chronic difficulty falling asleep, frequent awakenings from sleep, and/or a short sleep or nonrestorative sleep. People with insomnia experience EDS and insufficient sleep quantity and quality. It occurs more frequently in and is the most common sleep problem for women. People experience transient insomnia as a result of situational stresses. If the condition continues, the fear of not being able to sleep is enough to cause wakefulness.

Sleep Regulation

Instruments such as the electroencephalogram (EEG), which measures electrical activity in the cerebral cortex; the electromyogram (EMG), which measures muscle tone; and the electrooculogram (EOG), which measures eye movements provide information about some structural physiological aspects of sleep. The major sleep center in the body is the hypothalamus. It secretes hypocretins (orexins) that promote wakefulness and rapid eye movement (REM) sleep. Prostaglandin D2, L-tryptophan, and growth factors control sleep. Researchers believe that the ascending reticular activating system (RAS) located in the upper brainstem contains special cells that maintain alertness and wakefulness.

Pharmacological Approaches.

Melatonin is a neurohormone produced in the brain that helps control circadian rhythms and promote sleep. The recommended dose is 0.3 to 1 mg taken 2 hours before bedtime. Ramelteon (Rozerem), a melatonin receptor agonist, is well tolerated and appears to be effective in improving sleep by improving the circadian rhythm and shortening time-to-sleep onset. Valerian is effective in mild insomnia and RLS. Kava helps promote sleep in patients with anxiety. Chamomile, an herbal tea, has a mild sedative effect that may be beneficial in promoting sleep. Over the long term these drugs lead to further sleep disruption, even when they initially seemed effective.

Young Adults.

Most young adults average 6 to 8 1/2 hours of sleep a night. Approximately 20% of sleep time is REM sleep. Pregnancy increases the need for sleep and rest. Daytime drowsiness, insomnia, and nighttime awakenings also increase because of frequent nocturnal voiding. These disturbances level off in the second trimester. Insomnia, periodic limb movements, RLS, and sleep-disordered breathing are common problems during the third trimester of pregnancy.

Functions of Sleep

NREM sleep contributes to body tissue restoration. During NREM sleep biological functions slow. During sleep the heart rate falls to 60 beats/min or less, which benefits cardiac function. Other biological functions decreased during sleep are respirations, blood pressure, and muscle tone. It also lowers the basal metabolic rate and further conserves body energy supply. REM sleep is necessary for brain tissue restoration and appears to be important for cognitive restoration and memory. A loss of REM sleep leads to feelings of confusion and suspicion. Changes in the natural and cellular immune function also occur with moderate-to-severe sleep deprivation.

Stages of Sleep

Normal sleep involves two phases: nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep (Box 43-1). During NREM a sleeper progresses through four stages during a typical 90-minute sleep cycle. The quality of sleep from stage 1 through stage 4 becomes increasingly deep. Lighter sleep is characteristic of stages 1 and 2, during which a person is more easily aroused. Stages 3 and 4 involve a deeper sleep, called slow-wave sleep. REM sleep is the phase at the end of each sleep cycle.

Preschoolers.

On average a preschooler sleeps about 12 hours a night (about 20% is REM). By the age of 5 he or she rarely takes daytime naps. Partial awakening followed by normal return to sleep is frequent. In the awake period the child exhibits brief crying, walking around, unintelligible speech, sleepwalking, or bed-wetting.

Adolescents.

On average the majority of teenagers get about 7 hours or less of sleep per night. Shortened sleep time often results in EDS, which frequently leads to reduced performance in school, vulnerability to accidents, behavior and mood problems, and increased use of alcohol.

Description of Sleeping Problems

Open-ended questions help a patient describe a problem more fully. A general description of the problem followed by more focused questions usually reveals specific characteristics that are useful in planning therapies.

Teamwork and Collaboration.

Other staff members need to be aware of the care plan so they can cluster activities at certain times to reduce awakenings. In a nursing home the focus of the plan involves better planning of rest periods around the activities of the other residents.

Promoting Safety: Acute Care

Patients with OSA who are given opioid analgesics after surgery have an increased risk of developing airway obstruction because the medications suppress normal arousal mechanisms. These patients often need ventilator support in the postoperative period because of the increased risk of respiratory complications. Monitor the patient's airway, respiratory rate and depth, and breath sounds frequently after surgery. Teach the patient to elevate the head of the bed and use a side or prone position for sleep. Use pillows to prevent a supine position. One of the most effective therapies is use of a nasal continuous positive airway pressure (CPAP) device at night.

Physical Illness

Patients with chronic lung disease such as emphysema are short of breath and frequently cannot sleep without two or three pillows to raise their heads. Sleep-related breathing disorders are linked to increased incidence of nocturnal angina (chest pain), increased heart rate, electrocardiogram changes, high blood pressure, and risk of heart diseases and stroke. Hypertension often causes early-morning awakening and fatigue. After repeated awakenings to urinate(nocturia), returning to sleep is difficult, and the sleep cycle is not complete. Many people experience restless legs syndrome (RLS), which occurs before sleep onset. Primary RLS is a CNS disorder. Researchers associate secondary RLS with lower levels of iron, pregnancy, renal failure, stress, diet, Parkinson's disease, or a side effect of drugs.

rest

Rest does not imply inactivity, although everyone often thinks of it as settling down in a comfortable chair or lying in bed. When people are at rest, they are in a state of mental, physical, and spiritual activity that leaves them feeling refreshed, rejuvenated, and ready to resume the activities of the day.

Obstructive Sleep Apnea.

Sleep apnea is a disorder characterized by the lack of airflow through the nose and mouth for periods of 10 seconds or longer during sleep. The most common form is obstructive sleep apnea (OSA). The two major risk factors for OSA are obesity and hypertension. Smoking, heart failure, type II diabetes, alcohol, and a positive family history of OSA also greatly increase the risk of developing the problem. Structural abnormalities such as a deviated septum, nasal polyps, certain jaw configurations, larger neck circumference, or enlarged tonsils predispose a patient to OSA. The effort to breathe during sleep results in arousals from deep sleep often to the stage 2 cycle. Excessive daytime sleepiness (EDS) and fatigue are the most common complaints of people with OSA. OSA causes a serious decline in arterial oxygen saturation level. Patients are at risk for cardiac dysrhythmias, right heart failure, pulmonary hypertension, angina attacks, stroke, and hypertension.

Through the Patient's Eyes.

Sleep is a subjective experience. Only the patient is able to report whether or not it is sufficient and restful. If a patient admits to or suspects a sleep problem, you will need a detailed history and assessment. If a patient has an obvious sleep problem, consider asking if his or her sleep partner can be approached for further assessment data. Always ask patients what they expect regarding sleep.

Sleep Cycle

The normal sleep pattern for an adult begins with a presleep period during which the person is aware only of a gradually developing sleepiness. This period normally lasts 10 to 30 minutes. Once asleep, the person usually passes through four or five complete sleep cycles per night, each consisting of four stages of NREM sleep and a period of REM sleep. Each cycle lasts approximately 90 to 100 minutes. A person usually reaches REM sleep about 90 minutes into the sleep cycle. With each successive cycle stages 3 and 4 shorten, and the period of REM lengthens. REM sleep lasts up to 60 minutes during the last sleep cycle.

Tools for Sleep Assessment.

Two effective subjective measures of sleep are the Epworth Sleepiness Scale and the Pittsburgh Sleep Quality Index. The Epworth Sleepiness Scale evaluates the severity of EDS. The Pittsburgh Sleep Quality Index assesses sleep quality and patterns. Another effective, brief method for assessing sleep quality is the use of a visual analog scale. Draw a straight horizontal line 100 mm (4 inches) long. Opposing statements such as "best night's sleep" and "worst night's sleep" are at opposite ends of the line. Ask patients to place a mark on the horizontal line at the point corresponding to their perceptions of the previous night's sleep. Measuring the distances of the mark along the line in millimeters offers a numerical value for satisfaction with sleep. Use the scale repeatedly to show change over time. Another brief subjective method to assess sleep is a numeric scale with a 0-to-10 sleep rating.

Sources for Sleep Assessment.

Usually patients are the best resource for describing sleep problems. In addition, bed partners are able to provide information about patients' sleep patterns that help reveal the nature of certain sleep disorders. When caring for children, seek information about sleep patterns from parents or guardians because they are usually a reliable source of information. Parents of infants need to keep a 24-hour log of their infant's waking and sleeping behavior for several days to determine the cause of the problem.

Insomnia

chronic difficulty falling asleep, frequent awakenings from sleep, and/or a short sleep or nonrestorative sleep

The Multiple Sleep Latency Test (MSLT)

provides objective information about sleepiness and selected aspects of sleep structure by measuring eye movements, muscle-tone changes, and brain electrical activity during at least four napping opportunities spread throughout the day. The MSLT takes 8 to 10 hours to complete.

polysomnogram

the use of EEG, EMG, and EOG to monitor stages of sleep and wakefulness during nighttime sleep

nocturia

excessive urination at night; especially common in older men

sleep hygeine

habits and practices that are conducive to sleeping well on a regular basis

Central sleep apnea (CSA)

involves dysfunction in the respiratory control center of the brain. The impulse to breathe fails temporarily, and nasal airflow and chest wall movement cease. The oxygen saturation of the blood falls. The condition is common in patients with brainstem injury, muscular dystrophy, and encephalitis. Patients with sleep apnea rarely achieve deep sleep. In addition to complaints of EDS, sleep attacks, fatigue, morning headaches, irritability, depression, difficulty concentrating, and decreased sex drive are common.

Key Points

• Sleep provides physiological and psychological restoration. • The 24-hour sleep-wake cycle is a circadian rhythm that influences physiological function and behavior. • The control and regulation of sleep depends on a balance among regulators within the CNS. • During a typical night's sleep a person passes through four to five complete sleep cycles. Each sleep cycle contains three NREM stages of sleep and a period of REM sleep. • The most common type of sleep disorder is insomnia. • The hectic pace of a person's lifestyle, emotional and psychological stress, and alcohol ingestion frequently disrupt the sleep pattern. • If a patient's sleep is adequate, assess his or her usual bedtime, normal bedtime ritual, preferred environment for sleeping, and usual preferred rising time. • When a patient has a sleep problem, conduct a complete sleep history. Identifying nursing diagnoses for sleep problems depends on identifying factors that impair sleep. • When planning interventions to promote sleep, consider the usual characteristics of the patient's home environment and normal lifestyle. • A regular bedtime routine of relaxing activities prepares a person physically and mentally for sleep. • An environment with a darkened room, reduced noise, comfortable bed, and good ventilation promotes sleep. • Important nursing interventions for promoting sleep in the hospitalized patient are establishing periods for uninterrupted sleep and rest and controlling noise levels. • Pain or other disease symptom control is essential to promoting the ability to sleep. • Long-term use of sleeping pills often leads to difficulty initiating and maintaining sleep.