Mometrix RPSGT Flashcards

Discuss the dissociative disorders that contribute to parasomnias.

Parasomnias include a number of different sleep-related dissociative disorders, such as:

Sleep-related hallucinations	Visual, auditory, or tactile hallucinations occur during onset of sleep (hypnagogic) or on waking (hypnopompic), sometimes associated with sleep paralysis. Images tend to be stationary and disappear if the light is switched on.
Sleep-related urologic disfunction (enuresis)	Enuresis is repeated, involuntary, urinary incontinence in children 5-6 years old. Enuresis is most common in the first third of the night with the child awakening after urinating. There are three types: Primary: The child has never been dry at night, and incontinence is associated with delay in maturation and small functional bladder rather than stress or psychiatric disorders Intermittent: The child stays dry part of the time with episodes of incontinence at night Secondary: The child has had long periods (6-12 months) of staying dry
Exploding Head Syndrome	Upon awakening, the patient perceives a sudden (imaginary) noise of explosion, sometimes accompanied by a flash of light, jerking, and fright.

Discuss parasomnias and the two categories of parasomnias

Parasomnias, physical phenomena associated with sleep, comprise a number of different disorders of arousal that are most common during childhood. Parasomnias can be divided into REM-related and NREM-related disorders.

NREM-related parasomnias include disorders of arousal (occurring during NREM sleep), confusional arousals, sleep walking, sleep terrors, and sleep-related eating disorders. REM-related parasomnias include REM sleep behavior disorder, recurrent isolated sleep paralysis, and nightmare disorder.

Discuss sleep deprivation

Sleep deprivation is becoming more common as many adults as well as teenagers and some children sleep less than 7 hours a night. Short-term sleep deprivation (1-2 days) seems to have no long-lasting effects, but long-term sleep deprivation can cause some of the following harmful effects

• Changes in thermoregulation

• Emotional lability

• Increased stress and increased response to stress

• Increased blood pressure

• Impaired functioning

• Increased risk of accidents (e.g., auto, machinery, falls)

• Chronic sleepiness and fatigue

When sleep deprivation is chronic, people often are unable to judge their degree of sleepiness, using common tests, such as the Stanford Sleepiness Scale, so subjective reports may not indicate the actual degree of sleepiness. The Epworth Sleepiness Scale is usually more accurate. Sleep deprivation may be related to poor health, medications, and lifestyle choices.

Discuss how Alzheimer’s disease contributes to sleep problems

Alzheimer disease and other causes of dementia result in behavior that can contribute to sleep problems. Dementia may interfere with sleep, and patients may have undiagnosed and untreated obstructive sleep apnea or other sleep disorders.

• Sundowners: Patients often have disruption of the sleep-wake cycle, and sundowner syndrome, in which the person becomes increasingly agitated and restless in the evening, is common as dementia advances.

• Wandering: Patients may become confused and begin to wander during the night or day and may become frightened and hide, compounding the problem. It is not clear why patients wander, but perhaps there is a physical need, such as the need to drink or urinate, that prompts them to get up and start walking. In some cases, they may just be walking and get lost.

Discuss the following factors that dictate readiness to learn: mental/emotional status and knowledge/education

There are a number of factors related to readiness to learn.

• Mental/emotional status: The support system and motivation may impact readiness. Anxiety, fear, or depression about a physical condition can make learning very difficult because the patient or family cannot focus on learning; thus, the technologist must spend time to reassure the patient and family and wait until they’re emotionally more receptive.

• Knowledge/education: The knowledge base of the patient and family, their cognitive ability, and their learning styles all affect their readiness to learn. The technologist begins by assessing what knowledge the patient and family already have about the disease, condition, or treatment and then builds from that base. People with little medical experience may lack knowledge of basic medical terminology, which may interfere with their ability and readiness to learn.

Discuss considerations when educating patients with a cognitive impairment

Cognitive impairment can be challenging, and patients may have very individual responses, so observation of the patient must serve as a guide. Patients may be apprehensive and frightened, so the technologist maintains a friendly, normal tone of voice and speaks with the patient often to establish rapport, even if the response is not clear. The technologist always asks the patient before touching his or her things. Initiating communications by talking about familiar things (e.g., family, pictures, the past) may be comforting for the patient. If responses are unclear or inappropriate, the technologist can say, “I didn’t understand that” but should not laugh or indicate frustration. The technologist should face the patient and maintain eye contact to help the patient stay focused. Patients may get up and move away or go for a walk, and the technologist should not try to restrain the patient but should ask if he or she can walk with the person.

Discuss the pathophysiology of sleep: Ventilation-perfusion

Ventilation-perfusion refers to oxygen diffusing across the alveolar membrane into the capillary blood. As oxygen in its gaseous form is exposed to the liquid blood, the oxygen dissolves until it reaches a state of equilibrium in which the partial pressure of the dissolved oxygen in the blood is equal to the partial pressure of oxygen in its gaseous state in the alveoli:

• Normal ventilation-perfusion: With normal lung function, blood passing by the alveoli is matched with an equal amount of gas, so ventilation matches perfusion (ratio 1:1)

• Low ventilation-perfusion: Shunting occurs when perfusion exceeds ventilation so that an adequate volume of blood passes by the alveoli, but the blood does not pick up adequate amounts of gas because obstruction, such as from atelectasis.

• High ventilation-perfusion: Dead space occurs because ventilation is adequate but not blood supply so gas exchange is impaired. This can occur with pulmonary embolism and shock.

• Silent unit: No or very little exchange occurs, such as with pneumothorax or acute respiratory distress syndrome.

Discuss substance-induced sleep disorders associated with cocaine and opioid use.

Sleep disorders can result from intoxication and withdrawal from cocaine/opioids.

Drug	Disorder	Characteristics
Cocaine intoxication	Insomnia	Sleep is severely compromised, and the patient may only sleep for short, disrupted periods.
Cocaine withdrawal	Hypersomnia	Sleep is markedly prolonged
Opioid use (chronic)	Insomnia	While acute use of opioids may result in increased sleepiness with reduced stage R sleep, chronic use may cause insomnia with increased wakefulness and decreased sleep time.
Opioid withdrawal	Hypersomnia	Sleep is prolonged

Discuss patient identification and informed consent

Patients’ identification is checked by the sleep technologist, following protocol established by the facility, and the records are reviewed carefully to ensure that correct patient identifier is on all paper and computer records.

Informed consent is provided by patients or family for all treatments the patient receives. This includes a thorough explanation of all procedures and treatments with their associated risks. Patients or family are apprised of all reasonable risks and any complications that might be life-threatening or increase morbidity. The American Medical Association has established guidelines for informed consent:

• Explanation of diagnosis

• Nature of, and reason for, treatment or procedure

• Risks and benefits

• Alternative options (regardless of cost or insurance coverage)

• Risks and benefits of alternative options

• Risks and benefits of not having a treatment or procedure

• Providing informed consent (a requirement of all states)

Discuss the pathophysiology of sleep: Primary respiratory function

The primary respiratory function is to facilitate the body’s cells to obtain energy from the oxidation of carbohydrates, fats, and proteins, a process that requires oxygen and generates carbon dioxide as a byproduct.

Oxygen Transport	Blood circulates to carry oxygen to the cells and to remove carbon dioxide by diffusion at the capillary level
Respiration	Gas exchange occurs between the atmospheric air and the blood between the blood and the body cell The capillaries in the lungs have a lower concentration of oxygen than the alveoli, so oxygen diffuses into the blood The capillaries have a higher concentration of carbon dioxide than the alveoli, so carbon dioxide diffuses into the alveoli
Ventilation	Air flows into the lungs during inspiration and back into the atmosphere during expiration with airflow governed by variances in air pressure, airway resistance, and compliance

Discuss the disorders associated symptoms that may be discussed in the patient’s history or physical

The history and physical is reviewed by the technician before the first meeting with the patient, if possible, as this information can guide the initial assessment as well as the evaluation during and after the testing.

Sleep disorders	Obstructive/central sleep apnea, narcolepsy, circadian rhythm disorders, restless legs syndrome, periodic leg movement, parasomnias, and insomnia
Respiratory disorders	Chronic obstructive pulmonary disease, cystic fibrosis, restrictive lung diseases, and asthma
Neuromuscular diseases	Multiple sclerosis, amyotrophic lateral sclerosis, myasthenia gravis, poliomyelitis, and myotonic dystrophy
Spinal cord injury	Bilateral diaphragmatic paralysis
Gastrointestinal disorders	Gastroesophageal reflux disease and functional bowel disorders
Endocrine disorders	Hypothyroidism, acromegaly, Cushing syndrome, Addison disease, diabetes mellitus, and diabetes insipidus
Rheumatologic disorders	Pain syndromes and fibromyalgia
Kidney/urinary disorders	End-stage renal disease and urinary frequency
Infectious diseases	HIV/AIDS, Lyme disease, and human African trypanosomiasis
Cardiovascular disorders	Heart block, dysrhythmias, congestive heart failure, coronary artery disease, and atrial fibrillation
Psychiatric disorders	Bipolar disorder, depression, PTSD, and schizophrenia

Discuss the physiological effects of sleep on children with pulmonary disorders

The physiological effects of sleep must be considered with children with pulmonary disorders because sleep can exacerbate respiratory problems.

• Reduced tidal volume resulting in reduced lung volume and minute ventilation

• Reduced functional residual volume (and reduced store of oxygen), resulting from hypotonia of respiratory muscles (primarily during stage R sleep), displacement of the diaphragm (cephalad), central pooling of blood, and increased elasticity of lungs

• Increased chest wall compliance from muscle hypotonia

• Increased airway resistance

• Decreased basal metabolic rate, resulting in decreased production of carbon dioxide counterbalanced by a simultaneous decrease in alveolar ventilation that results in an overall increase in carbon dioxide by 506 torr above normal value

• Decreased central nervous system response to chemical changes (e.g., hypoxia, hypercapnia) or mechanical changes (e.g., respirations), resulting in reduced respiratory drive (again increasing carbon dioxide), especially during stage R sleep

• Altered arousal threshold

Discuss the importance of infant and pediatric polysomnography for those patients with neuromuscular diseases

Infant and pediatric polysomnography is an essential component of evaluation of children with neuromuscular diseases to determine cardiorespiratory impairment and to establish the need for assisted ventilation during sleep because impaired sleeping/ventilation increases the risk of respiratory failure. Polysomnography should be done as soon after diagnosis as possible to establish baseline readings, followed by periodic polysomnography to note the progress of the disease. Because of the child’s impaired sensation or ability to move, care must be taken during the polysomnogram to prevent injury or irritation

• Lifts are available to assist in moving older children

• The child’s body is positioned with adequate cushioning and support, using pillows or bolsters, making sure to maintain proper body alignment

• Linens must be kept smooth and free of wrinkles

• The child must be turned and moved carefully, avoiding jerking

Discuss treatment and intervention for narcolepsy

Narcolepsy intervention includes a number of measures to maintain wakefulness and prevent the person from falling asleep

• Stimulants: Amphetamines (dextroamphetamine, methamphetamine), or amphetamine-like drugs (methylphenidate) decrease daytime sleepiness and reduce daytime sleeping but may cause hypertension, tachycardia, anxiety, headache, and gastrointestinal problems. The potential for abuse exists Modafinil (Provigil), a dopamine agonist, is similar in action to amphetamines but has fewer side effects to it is usually the preferred drug. Secondary to modafinil are pitolisant and solriamfetol.

• Tricyclic antidepressants (TCAs): TCAs (protriptyline, clomipramine, desipramine) reduce stage R sleep, control cataplexy, and reduce hypnagogic or hypnopompic hallucinations and sleep paralysis. Adverse effects include dry mouth, muscle twitching, constipation, tachycardia, urinary retention, confusion, appetite changes, hypotension, and sexual dysfunction

• Selective serotonin re-uptake inhibitors (SSRIs) SSRI antidepressants (fluoxetine, duloxetine) work similarly to TCAs but usually have fewer adverse effects. Adverse effects can include apathy, appetite changes, increased depression, suicidal ideation, tremors, bruxism (grinding teeth), and sexual dysfunction

Discuss the pathophysiology of sleep: Hemodynamic terms

Key terms related to hemodynamics include the following:

• Cardiac output (CO) is the amount of blood pumped through ventricles, usually calculated in liters per minute. Normal value at rest are 4-6 L/min

• Cardiac Index (CI) is the cardiac output divided by the body surface area (BSA) (CI = CO divided by BSA). This is essentially a measure of cardiac output tailored to the individual, based on height and weight, measured in liters per minute per square meter of body surface area. Normal values are 2.2-4.0 L/min/m²

• Stroke volume (SV) is the amount of blood pumped through the left ventricle with each contraction, minus any blood remaining inside the ventricle at the end of systole. Normal values are 50-100 mL. The formula is below:

  • CO (L/min) / HR (beats/min) * (100) = SV (mL)

• Pulmonary vascular resistance (PVR) is the resistance in the pulmonary arteries and arterioles against which the right ventricle has to pump during contraction. It is the mean pressure in the pulmonary vascular bed divided by blood flow. If PVR increases, SV decreases. Normal value are 0.25-2.0 Wood units or 40-250 dynes/sec/cm⁵

Discuss obstructive sleep apnea, including symptoms and testing results for this sleep disorder

Obstructive sleep apnea results from the passive collapse of the pharynx during sleep, often associated with a narrow or restricted upper airway during micrognathia, obesity, or enlarged tonsils. It is most common in middle-aged, overweight men, and is exacerbated by drinking alcohol or ingesting sedative drugs before sleeping. Symptoms include daytime somnolence, headache, cognitive impairment, depression, personality changes, recent increase in weight, and impotence. Patients often snore loudly with cycles of breath cessation caused by apneic periods up to 60 seconds, occurring at least 30 times a night despite continued chest wall and abdominal movements, indicating an automatic attempt to breathe. Electrocardiographic changes may indicate bradydysrhythmia during apnea and tachydysrhythmia when breathing resumes. Nocturnal polysomnography shows 5+ obstructive respiratory events per hours of sleep. There may be hypopnea with reduction of airflow. Both apneic and hypopneic periods result in reduced oxyhemoglobin saturation. If this condition is severe, hypoxemia and hypercarbia may persist during waking hours.

Discuss Bloom’s taxonomy its three types of learning

Bloom’s taxonomy outlines behaviors that are necessary for learning and describes three types of learning: cognitive, affective, and psychomotor

Cognitive (learning and gaining intellectual skills to master six categories of effective learning)	Knowledge Comprehension Analysis Synthesis Evaluation
Affective (recognizing five categories of feelings and values from simple to complex; slower to achieve than cognitive learning)	Receiving phenomena: Accepts the need to learn Responding to phenomena: Takes an active part in care Valuing: Understands value of becoming independent in care Organizing values: Understands how surgery or treatment has improved life Internalizing values: Accepts condition as part of life; is consistent and self-reliant
Psychomotor (mastering six motor skills necessary for independence; follows a progression from simple to complex)	Perception: Uses sensory information to learn tasks Set: Shows willingness to perform tasks Guided response: Follows directions Mechanism: Does specific tasks Complex over response: Displays competence in self-care Adaptation: Modifies procedures as needed Origination: Creatively deals with problems

Discuss substance-induced sleep disorders associated with the use of prescription drugs (A-Z)

Sleep disorders may also result from commonly prescribed drugs

Drug	Disorder	Characteristics
Antiarrhythmics (quinidine, procainamide)	Insomnia	These drugs may cause disruption of sleep during the night and increased sleepiness in the waking hours
Antihistamines (diphenhydramine, Benadryl)	Hypersomnia	Some drugs produce a sedative effect, causing increased sleeping during the night and increased sleepiness during the daytime.
B-Blockers (Beta blockers)	Insomnia	B-Blockers decrease sleep, increase disruption of sleep, and increase nightmares
Bronchodilators (theophylline)	Insomnia	High doses of some bronchodilators may cause nervousness, muscle cramping, twitching, and sleep disruption
Corticosteroids	Insomnia	Steroids may markedly decrease sleep time and increase time needed to fall asleep as well as cause fatigue and jitters during the day
Diuretics	Insomnia	Decreasing potassium levels may cause leg cramps that interfere with sleeping, and the increase in urinary output may cause nocturia, interrupting sleep
Nicotine patches	Insomnia	Patches may interfere with falling asleep and duration of sleep and cause vivid dreams or nightmares
Selective serotonin reuptake inhibitors (SSRIs)	Insomnia	Some individuals experience sleep disruption and sleepiness during waking hours when taking SSRIs
Thyroid hormone (Synthroid)	Insomnia	High doses of thyroid hormone may cause nervousness, tremors, heart palpitations, and disruption of sleep

Discuss elements of the pre-sleep questionnaire

Pre-sleep questionnaires are usually standardized forms that review issues related to sleep, but the technologist asks additional questions for clarification as needed. The questionnaire helps to determine if the patient’s preceding 24 hours were normal for that individual. Topics covered include the following:

Sleep preparation	Activities done before bedtime, such as showering, exercising, watching television, or reading in bed
Sleep patterns	Usual time to bed, time to rise, and time needed to fall asleep
Sleep position	Side lying, supine, prone, and number of pillows
Sleep problems	Restlessness, restless legs, insomnia, snoring, gasping, choking, or apneic periods
Sleep arrangement	Sleeps alone, has bed partner, or sleeps with animals on bed
Sleep aids	Sleeping medications, music, television, or reading
Habits	Smoking, drinking, including the type, amount, and time used within 24 hours of testing
Nocturia	Frequency of using the bathroom during night
Other physical complaints	Dry mouth on arising, nasal congestion, or headaches in the morning
Daytime patterns	Sleepiness in the morning, tiredness through day, falling asleep inappropriately, needing naps, and duration and frequency of naps
Medications	All medications taken within 24 hours of testing

Discuss the impact of fibromyalgia and chronic fatigue syndrome on sleep

Fibromyalgia is a complex syndrome of disorders that include fatigue, chronic generalized muscle pain, and focal areas of tenderness, persisting for at least 3 months. The causes of fibromyalgia is not clear and has only recently been recognized as a distinct disorder. About 80% of patients with fibromyalgia also have episodes of central sleep apnea, which causes the person to arouse. Additionally, 40% or more people have restless legs syndrome or periodic limb movement disorder. Bruxism (grinding of the teeth) is also common. A polysomnogram typically shows that patients are able to go to sleep, but during non-REM sleep, alpha spiking occurs, resulting in feelings of chronic fatigue.

Chronic fatigue syndrome (CFS), a condition in which the patient complains of unrelenting fatigue, unrelated to activity, is also characterized by an alpha electroencephalogram sleep anomaly. Both fibromyalgia and CFS are characterized by increased sleep latency, decreased slow-wave sleep, reduced stage R sleep, decreased sleep efficiency, and increased motor activity.

Discuss the polysomnogram indicative of parasomnias

Parasomnias	Polysomnogram
Confusional arousals	Shows alpha waves, repetitive periods of microsleep, or stage N1 sleep during arousal period
Sleep-related urologic disfunction (enuresis)	Typically normal
Exploding head syndrome	Shows sudden arousal during transition period between sleep and awakening, and electroencephalogram shows alpha and theta waves
Nightmares	Shows sudden arousal from stage R sleep and abnormalities in stage R sleep
REM behavior disorder	Show muscle activity during REM sleep
Sleep paralysis	Shows muscle atonia and alpha waves
Sleep-related eating	May show multiple arousals from stage N3 sleep and sometimes stage R sleep
Sleep-related hallucinations	Shows onset usually during sleep-onset stage R sleep periods but also during NREM sleep

Discuss the impact of generalized anxiety disorder on sleep

Generalized anxiety disorder (GAD) is an unrealistic apprehension and worry that persists for 6 or more months. Unlike phobias, this is a general anxiety that is not triggered by a specific object or situation. GAD may be accompanied by tension, sweating, irritability, and hypervigilance. It occurs more frequently in women than men and is common in the elderly. Up to 70% of affected people report difficulty sleeping, including insomnia and sleep deprivation, which may be related to symptoms, such as tremulousness and muscle tension, autonomic arousal (i.e., shortness of breath, tachycardia, dry mouth, diarrhea), depression, and generalized fear and anxiety. Polysomnography shows a delay in onset of sleep, decreased slow-wave sleep, and total sleep time, increased stage N1 sleep, and frequent arousals during the first half of the night. The REM latency period is about 90 minutes long, within normal range, but REM density is decreased

Discuss bed partner questionnaires

Bed partner questionnaires are filled out by the patient’s bed partner (or in some cases a roommate or parent) with the patient’s permission. The partner is often aware of snoring or periods of apnea, even though the patient may not be aware. A typical questionnaire includes the following information:

• Patient and reporter’s namesF

• Frequency with which the reporter has observed the patient sleeping

• Positions in which the patient typically sleeps (back, stomach, right side, left side) and an estimate of the percentage of the night in each position

• Descriptions of sleep behaviors (usually with a checklist)

  • Type of snoring: light, loud, or snorting

  • Respiratory changes: choking or pauses

  • Extremities: twitching or jerking

  • Seizure-like activity: rigidity or shaking

  • Mouth activity: teeth grinding

  • Abnormal sleep behavior: sleep walking, talking, crying, sitting up, banging head, or rocking

  • Awakening behavior: alert, lethargic, or complaining of pain

Discuss the NREM-related parasomnia of disorders of arousal, and summarize confusional arousals and sleep-related eating disorder

Disorders of arousal are those that involve incomplete arousal during deep sleep and can be subdivided into confusional arousals, sleep walking, and sleep terrors. These episodes are characterized by recurrence and are not responsive to efforts of others to redirect or awaken. They are not associated with other sleep disorders and often involve amnesia (partial or complete) during the episode.

Confusional arousals, one subtype of disorders of arousal, are those in that the individual displays mental confusion or disorientation while in bed, but there is no evidence of fear or terror, and no ambulating from the bed.

Sleep-related eating is another disorder of arousal in which the patient eats during the night and has no recollection of doing so. This is distinct from night eating syndrome in which the patient is aware of eating but unable to go back to sleep without eating. Some sleeping medications may precipitate sleep-relate eating. There is also the risk of choking or aspiration

Discuss the process of obtaining consent from the pediatric population

Informed consent for medical treatments and testing cannot be provided by children younger than 18 years of age (minors), unless they are legally emancipated, until they reach the age of majority, except for certain treatments or testing approved by the law, such as for birth control, abortion, and HIV testing; however, even laws concerning these situations vary from state to state, with some requiring parental notification. However, children must be included in discussions about treatment options and testing in accordance with their age and level of understanding. Because children do not always appreciate cause and effect relationships, the law allows the parents to override decisions of the child and teenager, but forcing a child to have treatment or testing puts the child in a poor emotional state and is cause for ethical concern. Therefore, the sleep technologist should work with both the parents and the child, explaining the benefits and disadvantages of testing, to bring about agreement or assent on the part of the child. This is especially important for adolescents, who are seeking autonomy.

Discuss the pathophysiology of sleep: Ventilation (air pressure variances, airway resistance, and compliance)

Ventilation carries air with oxygen into the lungs and waste products, including carbon dioxide, out of the lungs. Important factors include air pressure variances and airway resistance.

Air pressure variances:

• Inspiration: The thorax expands and lowers the pressure in the thoracic cavity relative to atmospheric pressure, drawing air into the alveoli

• Expiration: The diaphragm relaxes, and the lungs contract; pressure inside the alveoli increases relative to atmospheric pressure, causing air to flow out of the lungs

Airway resistance: Resistance directly relates to the size of the airway, so changes in size can increases resistance, requiring an increased effort of breathing:

• Bronchial contraction of smooth muscles (asthma)

• Mucosal hyperplasia (chronic bronchitis)

• Airway obstruction (tumor, mucus, foreign body)

• Dilation or loss of elasticity as with chronic obstructive pulmonary disease (COPD)

Discuss the neurotransmitters involved in sleep

Neurotransmitters involved in sleep include the following:

Acetylcholine	Levels increase during the wake state and during stage R sleep, but levels decrease during stages N1, N2, and N3 sleep
Adenosine	Levels increase during periods of sleep deprivation and decrease while sleeping to recover. Some drugs, such as theophylline and caffeine, suppress the function of adenosine
Dopamine	Levels increase during the wake state and during stage R sleep. Some stimulants, such as methamphetamine, increase levels
Gamma-aminobutyric acid	Levels increase to inhibit the central nervous system
Glutamate	Levels increase to stimulate the central nervous system
Glycine	Levels increase to inhibit the motor nervous system at the spinal cord to cause antonia during stage R sleep
Histamine	Levels increase during the wake state. Agents that block histamine-1 receptors increase drowsiness
Hypocretin 1, 2	Levels increase during the wake state and regulate the circadian cycle. Impairment of hypocretin production or utilization can cause narcolepsy
Immuno-modulators with sleep factors	Levels increase non-REM sleep (insulin interleukin I, inerferon-a2, tumor necrosis factor) Levels increase REM sleep (somatostatin, growth hormone, prolactin) Levels increase both non-REM and REM sleep (prostaglandin D2, growth hormone-releasing factor) Levels inhibit sleep (glucocorticoids, prostaglandin E2, corticotropin-releasing factor, thyrotropin-releasing hormone
Melatonin	Levels increase during the evening and night and begin to decrease in the morning, helping to control the sleep-wake cycle
Norepinephrine	Levels increase to maintain the awake state, so levels decrease during stages N1, N2, and N3 sleep and are absent in stage R sleep
Serotonin	Levels increase during the awake state but decrease during non-REM and REM sleep to help regulate sleep onset with lowest levels during REM

Discuss the impact of the menstrual cycle on sleep

The menstrual cycle can affect sleep. The reproductive cycle includes:

Phase	Description	Effect
Follicular	The endometrial lining sheds (menstruation), and hormone levels of estradiol, progesterone, and luteinizing hormone (LH) decrease; follicle-stimulating hormone (FSH) increases to develop a new follicle and renew the endometrial lining. By the 4th day, estradiol levels rise, causing FSH levels to fall and LH levels to increase again	OSAS increases: Upper airway swelling. Pain from abdominal cramping or profuse drainage, which may impair sleep
Ovulation	The dominant follicle secretes increased estradiol, causing the pituitary gland to secrete LH, with a surge at days 11-13, causing follicular rupture and ovulation	Discomfort during ovulation may impair sleep
Luteal	Estradiol levels fall while progesterone levels increase 24 hours after ovulation, forming the corpus luteum from the ruptured follicle. The uterine lining enlarges. Without fertilization, both estradiol and progesterone levels fall, leading again to menstruation	OSAS decreases: Increased respiratory drive Increased pharyngeal stability Increased response to hypercapnia and hypoxia

Discuss how a spinal cord injury can impact respirations and sleep

Neuromuscular diseases can impair respiratory muscles, including pharyngeal, intercostal, and diaphragm muscles, resulting in the increased risk of OSA as well as aspirations during sleep and hypoventilation. The PSG aids in determining respiratory impairment and the needed for assisted ventilation

Impairment relates to the level of the injury:

• C4 and higher: Complete paralysis of muscles of respiration (i.e., intercostal, diaphragmatic, abdominal), so the patient requires a ventilator

• C4-T6: Varying degrees of muscle weakness and paralysis, so even though the patient does not require a ventilator, respirations may not be adequate

• T6-T12: Allows for normal breathing, but the muscles that control cough are impaired

• Below T12: Does not affect muscles related to respirations or coughing

The PSG assesses the patient for hypoventilation and hypoxia

Discuss idiopathic hypersomnia, including symptoms and testing results for this sleep disorder

Hypersomnia is characterized by increased sleepiness and prolonged nocturnal sleep (8-12) hours and daytime sleepiness (characterized by intentional or non-intentional napping) on a daily basis for at least three months, with difficulty awakening, resulting in social, occupational, and other impairment. This is idiopathic in nature with insufficient sleep and other sleep-wake disorders being ruled out. Intentional naps usually last an hour or more and non-intentional napping occurs during times of low stimulation, such as while watching television or driving. Cataplexy is not present. Nocturnal polysomnography shows normal to prolonged sleep and sleep continuity with normal sleep stage periods. The multiple sleep latency test shows excess sleepiness during the daytime with mean sleep latency of ≤8 minutes. Onset is usually between the ages of 15 and 30 years with symptoms worsening over time and eventually stabilizing. The recurrent form lasts for periods of at least 3 days and occurs several times yearly for 2 years or more.

Discuss the pathophysiology of sleep: Hemodynamics

Hemodynamics is based on the principle that fluid flows from areas of higher pressure to areas of lower pressure:

• Systole: Pressure rises in the ventricles, closing tricuspid and mitral (atrioventricular valves), stopping flow from the atria and preventing backflow (regurgitation). Pressure forces the pulmonic and aortic valves (semilunar valves) open, sending blood into both the aorta and pulmonary artery. Early ventricular systolic pressure is high, and then falls near the end of systole as the ventricles empty, lowering the pressure in the aorta and pulmonary artery, causing atrioventricular valves to close.

• Diastole: Ventricles are relaxed and atrioventricular valves open. Pressure in the atria is lower than in the venae cavae or the pulmonary veins, pulling blood into the atria with some to the ventricles. An electrical impulse is generated in the sinoatrial node, forcing the atria to contract, increasing the pressure and forcing more blood through the valves and into the ventricles. This period is atrial systole and occurs near the end of ventricular diastole.

Describe the testing required before starting PAP therapy

Testing with a PSG is usually done before positive airway pressure (PAP) is titrated to determine the type of sleep disorder and the need for PAP. This is done in one of two ways:

• Two-day testing: The first day of testing involves a nocturnal PSG for diagnosis. If OSA is found, then the patient returns for another night during which continuous PAP titration is completed to determine adequate settings to control apnea

• Split-night testing: This testing uses the first half of the night for a diagnostic PSG. If a clear pattern of OSA is present (≥40 apneas-hypopneas in 2 hours or an apnea-hypopnea index of 20-40 with significant oxygen desaturation during this period) or if a diagnosis of OSA has already been made, titration is done in the second half of the night (at least 3 hours). This testing may be used for both the initial diagnosis and followup to determine the persistence of symptoms and the effectiveness of treatment

Discuss the differences between continuous and automatic airway pressure

The differences between continuous (CPAP) and automatic (APAP) airway pressures have been evaluated by a number of small studies with the following results:

• Apnea-hypopnea (AHI): Both CPAP and APAP are equally effective in reducing AHI

• Oxygen saturation (SpO2): SpO2 improves with both CPAP and APAP but APAP is associated with a slightly lower average saturation level

• Sleep effectiveness: Both CPAP and APAP are effective in improving the quality of sleep, including reducing arousals and increasing stage R sleep. Patients requiring high pressures to prevent OSas usually find sleep quality is better with APAP

• Daytime sleepiness (Epworth Sleepiness Score): APAP and CPAP are generally similar, but some patients, especially those whose OSA is dependent on body position or stage of sleep, rate APAP higher

• Airway pressure: Average airway pressure is lower with APAP than CPAP because of pressure variability

• Patient compliance: Overall compliance is similar with APAP and CPAP

Discuss the concept of sleep hygiene

Sleep hygiene, that is, these methods, interventions, and activities that help patients fall and stay asleep, must be understood by patients. While sleep hygiene is usually not sufficient to treat chronic insomnia, it may help those with milder insomnia or other sleep-related disorders. Methods include the following:

• Use the bed only for sleep (or sex) but not for other activities such as watching television or reading

• Get out of bed after 20 minutes if not asleep and do something relaxing (e.g., reading) until sleepy

• Do not sleep anywhere except in bed, and only go to bed when sleepy

• Engage in activities that promote sleep, such as exercise in the afternoon or early evening, or a bedtime snack

• Avoid activities that interfere with sleep, such as smoking, drinking caffeinated drinks, using alcohol, or taking daytime naps

Discuss the pathophysiology of sleep: The respiratory system during the awake stage

The respiratory system during the awake stage is under primary control of the autonomic nervous system. However, speaking and eating can interfere with respirations, and they can also be controlled voluntarily, such as when a person holds their breath. The upper respiratory tract, including the nose, nasal passages, sinuses, pharynx, tonsils, adenoids, larynx, and trachea, warms, filters, and moistens the air that is inhaled, but obstruction of the upper respiratory tract may interfere with this function and cause people to become mouth breathers. While breathing through the mouth occurs with exercise, chronic mouth breathing can cause dryness of the mucous membranes in the mouth and can result in abnormalities of facial growth in children. The lower respiratory tract (the lungs) accomplishes gas exchange, that is, oxygen for carbon dioxide

Discuss the pathophysiology of sleep: The gastrointestinal tract during sleep

The gastrointestinal tract during sleep slows down as a protective mechanism to prevent aspiration. Less salvia is produced, esophageal motility decreases, and the patient swallows less; however, the production of gastric acid increases during the night (peaking from 10 pm to 2 am) in response to stimulation of the parasympathetic nervous system. Stomach emptying slows down during sleep. These changes pose a problem for patients with gastroesophageal reflux disease (GERD) because the increased acid flows back into the esophagus at the same time that clearance of secretions in the esophagus slows. This increases the risk of obstructive sleep apnea. Arousal, in turn, stimulates swallowing. Gastric peristalsis decreases during N1, N2, and N3 sleep but not in stage R sleep, resulting in fewer episodes of GERD during stage R sleep. Pain or discomfort related to gastrointestinal disorders can disrupt sleep significantly. It is likely that GERD will increase during sleep if the patient lies in the right lateral decubitus position.

Discuss Knowles’ theory of andragogy

Knowles’ theory of andragogy pertains to adult learners who are more interested in process than in information and content. Knowles outlined some principles of adult learning ad typical characteristics of adult learners.

Practical and goal-oriented	Provide overviews or summaries and examples Uses collaborative discussions with problem-solving exercises Remain organized with the goal in mind
Self-directed	Provide active involvement, asking for input Allow different options toward achieving the goal Give them responsibilities
Knowledgeable	Show respect for their life experiences and education Validate their knowledge, and ask for feedback Relate new material to information with which they are familiar
Relevancy-oriented	Explain how information will be applied Clearly identify objectives
Motivated	Provide certificates of achievement or some type of recognition for achievement

Discuss the sleep requirements for children

Sleep requirements for children slowly decrease as they eliminate daytime naps and become more engaged in activities

1-2 years	As the infant becomes more active, the nighttime requirements remain at 10.75 hours, but daytime sleeping of two naps decreases in duration to 2-3 hours for a total of 13 hours sleep by age 2
3-4 years	During this transitional stage, the child’s nighttime sleeping time increases slightly as the daytime nap is eliminated, so those napping sleep a total of 10.25 hours during the night (plus a daytime nap), increasing 11.5 hours when naps cease
5-8 years	The child is more active, and the schedule is more regimented, precluding naps, as the child attends school with overall sleeping time decreasing from 11 hours total at 5 years to 10.25 hours at 8 years
9-11 years	As the child becomes more engaged in activities, total sleep time slowly decreases from 10 hours at age 9 to 9.5 hours by age 11

Outline the key elements to include when educating a patient on the importance of sleep therapy

There are several important benefits of sleep therapy for treating disorders that must be taught to sleep study patients:

• Feeling more awake during the day: When the brain gets the rest it needs during deep, uninterrupted sleep, a person feels more alert and focused during the day

• Sleeping better at night: Sleep disorders cause frequent awakenings during the night. When treated, the symptoms of the disorder are controlled, which decreases the number of times a person will wake up during the night

• Longterm health benefits: Untreated sleep disorders are linked to heart disease, hypertension, dysrhythmias, diabetes, stroke, and heart failure

• Avoid morning headaches: A morning headache is a common complaint from patients with a sleep disorder. This is due to the dilation of the blood vessels due to increased carbon dioxide levels caused by apneic episodes.

• Decreased risk of accidents: Excessive sleepiness during the day can lead to work-related and motor vehicle accidents during the awake hours. According to the National Highway Safety Administration, drowsy driving causes 2.5% of fatal crashes and 2% of crashes causing injury

Discuss educating patients through the use of videos

Videos are a useful adjunct to teaching as they reduce the time needed for one-on-one instruction (increasing cost-effectiveness). Passive presentation of videos, such as in the waiting area, has little value, but focused viewing in which the technologist discusses the purpose of the video presentation before viewing and then is available for discussion after viewing can be very effective. Patients and families are often nervous about testing and unsure of their role, so they may not focus completely when the tech is presenting information. Allowing the patients and families to watcha video demonstration or explanation first and allowing them to stop or review the video presentation can help them to grasp the fundamentals before they have to apply them, relieving some of the anxiety they may be experiencing. Videos are much more effective than written materials for those with low literacy or poor English skills. The technologist should always be available to answer questions and discuss the material after the patients and families finish viewing.

Discuss the importance of demonstrating proper use of CPAP prior to patient use

Demonstration of CPAP with a nasal mask should be given to patients before titration so that they are comfortable with the equipment and understand how it functions. The initial demonstration should include:

• An explanation of the physiological changes during OSA and how they affect oxygen levels and breathing

• An explanation of the parameters of OSA, which are usually 15 periods of apnea or more, lasting 10 sec/min or more, an arousal demonstration by an electroencephalogram shift (≥ 3 seconds), or a drop in oxygen saturation (SpO2) by 3-4%

• Fitting of the mask, headgear, and straps so that they can be easily and quickly applied during the night

• Practice wearing the mask with and without air pressure

• An explanation of the titration process

Discuss the pathophysiology of sleep: Arterial blood gases

Arterial blood gases are sometimes monitored to assess the effectiveness of oxygenation, ventilation, and acid-base status and to determine oxygen flow rates. Partial pressure of a gas that is exerted by each gas in a mixture of gases, proportional to its concentration, based on total atmospheric pressure of 760 mmHg at sea level. Normal arterial blood gas values include the following:

• Acidity/alkalinity (pH): 7.35-7.45

• Partial pressure of carbon dioxide (PaCO2): 35-45 mmHg

• Partial pressure of oxygen (PaO2): ≥80 mmHg

• Bicarbonate concentration (HCO3): 22-26 mEq/L

• Oxygen saturation (SaO2): ≥95%

The relationship between these elements, particularly the PaCO2 and the PaO2 indicates respiratory status. For example, PaCO2 over 55 mmHg and the PaO2 under 60 mmHg in a patient previously in good health indicates respiratory failure. There many issues to consider. Ventilator management may require a higher PaCO2 to prevent barotrauma and a lower PaO2 to reduce oxygen toxicity

Discuss substance-induced sleep disorders associated with sedative/hypnotic use

Drug	Disorder	Characteristics
Sedative/hypnotic intoxication	Hypersomnia	Initial sedative effects result in an increase in sleepiness, decreased wakefulness, and a decrease in stage R sleep with an increase in sleep-spindle activity
Sedative/hypnotic chronic use/withdrawal	Mixed insomnia and hypersomnia	As the patients develops a tolerance for the drug, sedative effects decrease, and insomnia occurs. If the patient increases the dose of medication to compensate, then hypersomnia recurs. Withdrawal often results in insomnia with a decrease in sleep duration and an increased disruption of sleep and stage R sleep rebound as well anxiety, tremors, and ataxia.

Discuss substance-induced sleep disorders associated with amphetamine, stimulant, and caffeine use

Drug	Disorder	Characteristics
Amphetamines/related drugs: intoxication	Insomnia	Typically, total sleep is reduced with increased sleep latency and sleep disturbance. EMG shows increased muscular activity. Stage R sleep and slow-wave sleep decrease
Amphetamines/related drugs: withdrawal	Hypersomnia	Prolonged sleeping during the night. REM and slow-wave sleep may increase above baseline. MSLT shows increased sleepiness during the daytime as well.
Caffeine use	Insomnia	Increased wakefulness and decreased sleep are dose dependent. PSG shows increased sleep latency and wakefulness and decreased slow-wave sleep
Caffeine withdrawal	Hypersomnia	Increased sleeping and daytime sleepiness are common

Discuss recommendations that can be provided to patients suffering from sleep deprivation, such as night-shift workers

Night-shift workers are at increased risk for sleep deprivation and often cannot change working hours, which would be the ideal solution. Other interventions include:

• Sleep extra hours on days off (at least 2 days/week)

• Avoid working more than 12-16 hours at one time

• Monitor personal levels of alertness and impairment to increase safety

• Avoid drinking alcohol, which can increase sleepiness and impairment

• Avoid driving between 2 am and 9 am when most people are least alert

• Take a 45-minute or 2-hour nap before beginning the night shift

• Increase lighting at work to promote alertness

• Drink caffeinated drinks, such as coffee, 1 hour before a period of decreased alertness or increased sleepiness and stop ingestion at least 3 hours before sleep time as it may further impair sleeping

• Use Modafinil (prescription drug) to decrease sleepiness during the night (similar in effect to amphetamines but with fewer side effects)

Discuss the impact of dementia with Lewy bodies on sleep

Dementia with Lewy bodies is characterized by cognitive and physical decline similar to Alzheimer’s, but symptoms may fluctuate frequently. This form of dementia may include visual hallucinations, muscle rigidity, and tremors. PSG is used for diagnosis because a primary characteristic is REM behavior disorder (RBD), a parasomnia in which the paralysis (antonia) that usually accompanies stage R sleep is not present, so the person acts out activities of the dream, moving arms and sometimes grunting or shouting. RBD may also include sleepwalking and periodic leg movements. RBD is frequently one of the earliest symptoms, appearing before other indications of dementia. PSG montage incudes full EEG to rule out seizure disorders, video monitoring, and EMG for all extremities to monitor movement. A PSG may be done to monitor the effectiveness of treatment with clonazepam. Patients with dementia may become increasingly confused and sometimes belligerent or combative, so the technologist should avoid arguing and should try to keep explanations and stimulation to a minimum

Discuss the incorporation of handouts into patient education

Handouts are commonly used to teach patients; to be sure that they do not end up in the wastebasket without being read, these handouts should follow the following pointers:

• Handouts that simply copy a slide show presentation or repeat everything in the presentation are less helpful than those that summarize the main points.

• Providing handouts immediately before a discussion often results in the patient looking at the handout instead of the speaker. Thus, handouts should be given to the patient before instruction so they can be reviewed in advance or passed out at the end of the meeting

• Poster-type handouts (with drawings or pictures) that can be placed on bulletin boards are useful

• Handouts should be easily readable and not smudged copies of newspaper articles or small print text

Discuss the impact of frontal lobe epilepsy on sleep

Frontal lobe epilepsy and temporal lobe epilepsy are related to epileptiform discharges and seizure activity during sleep

Subtypes	Seizure Activity/Sleep Association
Benign focal epilepsy of childhood (Rolandic epilepsy)	Seizures are either generalized tonic-clonic or unilateral focal motor with oropharyngeal sensorimotor phenomena (e.g., hypersalivation, guttural sounds). Most seizures (75%) are nocturnal and are not associated with cognitive impairment. Interictal epileptiform activity (IEA) is especially evident during stage N3 sleep with interictal spikes
Supplementary sensorimotor	Seizures usually occur during sleep and are characterized by tonic posturing of extremities, usually asymmetrically with upper extremities. EEG shows interictal, high-amplitude, transient or sharp waves, maximum at vertex, with an electrodecremental pattern
Nocturnal frontal	Seizures vary widely and include brief (<20 seconds) paroxysmal arousal that may include sitting upright and vocalizing, nocturnal paroxysmal dystonia (20-120 seconds) with dystonic posturing and vocalizations, or episodic nocturnal wandering (1-3 minutes). Surface EEGs may not indicate activity during seizures, but IEA are evident with flattening of background, rhythmic theta and delta activity, and sharp waves (frontal)

Discuss the impact of stress and anxiety and the sympathetic nervous system on sleep

The sympathetic nervous system turns on the physiologic response to stress and anxiety and readies the body to react. The hypothalamus stimulates the pituitary gland to secrete a hormone, leading to increased cortisol levels. The sympathetic nervous system usually leads to decrease in blood flow in the gastrointestinal tract. This decreases appetite and movement of the intestinal tract. The neuromuscular system is charged up and ready to respond. Reflex time is increased, and there can be some twitching or shaking of muscles. The need for sleep is greatly reduced, leading to periods of insomnia. The facial expression may be tense and anxious, and the individual may actually pace about. The individual may have uncontrolled muscle movements, restlessness, and fast speech and may startle easily. The skin may become flushed or itchy with increased sweat gland production.

Discuss the impact of pulmonary hypertension

Pulmonary hypertension or pulmonary arterial hypertension (PAH) is a progressive disease that causes hypertension of the pulmonary arteries, restricting blood flow through the lungs and causing persistent hypoxia, especially on exertion. Primary PAH may result from immune responses, pulmonary emboli, sickle cell disease, collagen diseases, Raynaud disease, and the use of contraceptives. Secondary PAH may result from pulmonary vasoconstriction caused by hypoxemia related to COPD, sleep disordered breathing, kyphoscoliosis, obesity, smoke inhalation, altitude sickness, interstitial pneumonia, and neuromuscular disorders. While PAH my be one direct cause of sleep disordered breathing, all patients with PAH are at an increased risk of sleep disordered breathing and oxygen desaturation during sleep because of decreased ventilatory reserve; thus, oximetry should be carefully monitored as rates may fall to less than 90% sometimes for prolonged periods of time

Discuss the impact of focal or partial seizures on sleep

Focal or partial seizures are caused by an electrical discharge to a localized area of the cerebral cortex, such as the frontal, temporal, or parietal lobes, with seizure characteristics related to the area of involvement. They may begin in a focal area and become generalized, often preceded by an aura

• Simple partial: Unilateral motor symptoms including somatosensory, psychic, and autonomic

  • Aversive: Eyes and head turned away from focal side

  • Sylvan (usually during sleep): Tonic-clonic movements of the face, salivation, and arrested speech

• Special sensory: Various sensations (e.g., numbness, tingling, prickling, pain) spreading from one area; may include visual sensations, posturing, or hypertonia; rare in patients under 8 years old

• Complex (psychomotor): No loss of consciousness but altered consciousness and nonresponsive with amnesia; may involve complex sensorium with bad tastes, auditory or visual hallucinations, deja vu, or strong fear; may carry out repetitive activities such as walking, running, smacking lips, chewing, or drawling; rarely aggressive; seizure usually followed by prolonged drowsiness and confusion; occurs throughout adolescence

Discuss gender differences in sleep

Gender differences in sleep have been studied, but studies have varying information. Research done by the Sleep Heart Health Study (1997) suggests women sleep more effectively than men, beginning in adolescence and continuing through adulthood. As they age, men experience more deterioration of sleep than women:

• Increased stage N1 sleep

• Increased stage N2 sleep

• Higher apnea index

• Decreased stage N3 sleep

• Decreased stage R sleep

Women tend to report more insomnia then men but PSG does not support this, suggesting underlying disorders or sleep state misperception may cause women to report insomnia more frequently. The incidence of OSA in men is double that of women, especially with premenopausal women, but rates become more equal after women reach menopause. On the other hand, restless leg syndrome is more common in women (67%).

Discuss the procedure and process of PAP desensitization

PAP desensitization generally begins in the sleep clinic, and then continues in the home, until the patient feels comfortable with the mask and pressure and can return for a PAP titration study.

1. The first step involves measuring and selecting the appropriately sized mask for the patient, as ill-fitting masks can worsen feelings of claustrophobia, lead to air leaks, or cause discomfort that disrupts the patient. The sleep tech should be sure to allow the patient to be hands on with the mask, holding it to their face, confirming comfortable fit, and getting comfortable with its connections

2. While the patients holds the mask to their face, the pressure can be introduced, starting in small amounts, so the patient can remove the mask if uncomfortable. Pressure should start 2-4 cm H2O. Allow the patient to confirm comfort with the mask and pressure in this manner, and then have the patient remove the mask and fit it appropriately with the headgear.

3. Encourage the patient into a comfortable reclined position with the mask and headgear in place and reintroduce pressure, being sure to comfort the patient. If the patient is comfortable, pressure is slowly increased. If the patient is not comfortable, allow them to remain in low pressure. Sometimes methods such as distraction (music or TV) can be helpful

4. Increase pressure in increments of 1 cm H2O until reaching a pressure of 8 cm H2O. While doing this, be sure to check for air leaks and to assess the patient’s comfort. If the patient can withstand 8 cm H2O of pressure for 15 minutes, desensitization is considered successful.

After these stages have progressed, the patient is prepared to use PAP at bedtime, at first wearing it as long as possible (with a goal of at least 4 hours), and then increasing that time until it can be worn through the entirety of sleep time

Discuss considerations when educating patients with a visual impairment

Visual impairment is unrelated to intelligence of hearing, so the tech should speak with age-appropriate vocabulary in a normal tone, facing the patient so the tech can observe facial expressions Depending on the degree of visual impairment, the patient may not be able to see gestures of materials; so alternate forms of materials (braille handouts or enlarged text) or manipulatives must be considered. The field of vision may be impaired so that the patient sees shapes or has better vision in some areas than other; thus, the tech should try to position themself for the patient’s advantage. The tech should also announce their presence, explain actions or movement, announce position, and always tell the patient if the tech is going to touch the patient

Discuss the impact of pregnancy on sleep

Pregnancy can affect the ability to sleep

Trimester	Effects
First	Total sleep time (TST) increases about 30 minutes, and daytime sleepiness is common. Slow-wave sleep (SWS) declines. Progesterone levels rise, resulting in hypnotic effect and increased respiratory drive. Morning sickness may impair sleep in the morning
Second	TST decreases to pre-pregnancy levels, and SWS returns to normal. Morning sickness usually declines. The hypnotic effect of progesterone declines but causes increased urination, which can impair sleep. As the fetus grows, the functional residual capacity reduces, respiration requires increased energy, and shortness of breath increases, disrupting sleep
Third	TST remains at pre-pregnancy levels (although is may be slightly increased with daytime napping), but SWS and stage R sleep decrease. Mechanical pressure from the growing fetus can impair breathing. Nocturia, leg cramps, back pain, acid reflux, and general discomfort may increase and interrupt sleep. Restless legs syndrome and periodic limb movement syndrome increase during pregnancy, further disrupting sleep.

Discuss common abbreviations used for sleep technology

AI	Apnea index
AHI	Apnea-hypopnea index
CAP	Cyclic alternating pattern
EDS	Excessive daytime sleepiness
EPAP	Expiratory positive airway pressure
IEA	Interictal epileptiform activity
IPAP	Inspiratory positive airway pressure
Non-REM	Non-rapid eye movement
OA	Obstructive apnea
OH	Obstructive hypopnea
OSAS	Obstructive sleep apnea syndrome
OSA/H	Obstructive sleep apnea-hypopnea
PLMS	Periodic limb movements in sleep
PRC	Phase response curve
PSG	Polysomnogram
RBD	REM behavior disorder
RDI	Respiratory disturbance index
REM	Rapid eye movement
RERA	Respiratory effort-related arousals
RLS	Restless legs syndrome
SAH	Sleep apnea-hypopnea
SE	Sleep efficiency
SOL	Sleep onset latency
SWS	Short-wave sleep
SPT	Sleep period time
TST	Total sleep time
TSP	Total sleep period
TWT	Total wake time
WASO	Wake-after sleep onset

Discuss how pseudohypertrophic Duchenne muscular dystrophy can impact and sleep

Pseudohypertrophic Duchenne muscular dystrophy is the most common form of muscular dystrophy. Pseudohypertrophic refers to enlargement of the muscles by fatty infiltration associated with muscular atrophy, which causes contractures and deformities of joints and abnormal skeletal development, such as scoliosis, that can impair breathing. As the disease progresses, it involves the muscles of the diaphragm and other muscles, such as the oropharyngeal, which are needed for respiration. Sleep-disordered breathing may be obvious during PSG even though pulmonary function tests are normal during waking hours. Typical sleep-related problems include the following:

• Increasing sleep disruption

• Decrease in vital capacity to less than 2 L

• OSA

• Hypercapnia and oxygen desaturation during REM sleep, progressing to non-REM sleep as the condition worsens

Children whose disease has progressed may require ventilatory support

Discuss morning/evening questionnaires

Morning/evening questionnaires ask nineteen questions about time preferences, providing a range of answers that determines if the person is a morning, evening, or neutral person. (In 1976, Horne and Ostberg studied sleep patterns and classified people are “morning” or “evening” people, depending on their preferences for sleeping and arising and level of alertness.) Questions include:

• The time of day the patient would get up and go to bed if free to decide

• The degree of dependency on an alarm clock to awaken at the normally scheduled time

• The ease of getting up in the morning

• The patient’s feelings and appetite in the half hour after awakening

• The time of day the patient gets up on days with no obligations in relation to normal time to arise

• The ease with which the patient could engage in sports activities between 7 and 8 am or 10 and 11 pm

• The time of day when the patient feels tired enough to fall asleep

• The 2 hours of the day the patient would prefer to study for an exam

• How the patient feels in the morning after going to sleep at 11 pm

• The time which the patient would arise after going to bed several hours late; when the patient would sleep if having to stand guard from 4-6 am

• The 2 hours during the day that the patient would prefer to exercise

• The 5 consecutive hours during the day the patient would prefer to work

• The hour the patient feels the best

• Whether the patients considers themself to be a morning or evening person

Discuss chronic insomnia, including symptoms and testing results for this sleep disorder

Insomnia is characterized by a difficulty falling asleep, staying asleep, a combination of both, or having non-refreshing sleep. To be considered chronic, this must occur over prolonged periods of time (at least 3 times per week for at least 3 months). Individuals may have anxiety and functional impairment and are at risk for mood disorders. PSG may show continuity of sleep is interrupted with increased alpha and beta waves during sleep, although people usually are not sleepy in the daytime but may appear lethargic. They may exhibit variability in sleeping patterns from one night to another. They typically experience increased stage N1 and decreased stages N2 and N3 sleep. They may also complain of stress-related disorders, such as muscle tension and headaches, and may exhibit increased reactions to stress and increased metabolic rate. Individuals sometimes report better sleep in PSG lab than at home. Insomnia is a common problem occurring in children and adults, with chronic insomnia affecting 30% of the population. Insomnia may be precipitated by physical conditions, such as heart disease, gastroesophageal reflux disease, urinary incontinence, or psychiatric disorders. Insomnia is common with depression and bipolar disorder

Discuss the pathophysiology of sleep: Hypoxic drive

Respirations are primarily controlled by the level of arterial carbon dioxide (PaCO2) rather than the level of oxygen (PaO2). As carbon dioxide levels rise, this normally triggers an increased rate of respiration to compensate. In some cases, such as at high altitude, respirations can be triggered by hypoxemia; this is known as hypoxic drive because the concentration of ambient oxygen is lower. This same hypoxic drive can be triggered by patients with hypercarbia. Thus, when supplementary oxygen is delivered, the hypoxic drive, which has been triggering respirations, may decrease, resulting in hypopnea or apnea. Patients who are hypoxemic may still require oxygen, but administration must be carefully managed and the patient observed for changes in respiratory rate and effort. Patients with chronic obstructive pulmonary disease receiving high fractions of inspired oxygen may actually have increased carbon dioxide levels.

Describe the impact of temporal lobe epilepsy and electrical status epilepticus of sleep (ESES) on sleep

Temporal lobe epilepsy	Seizure activity is less frequent during sleep, although it does occur in some patients Increase in interictal epileptiform activity (IEA) in non-REM sleep with high-frequency spikes and contralateral focal discharges Decrease in stage R sleep
ESES	ESES is typically nonconvulsive but involves extensive epileptiform activity during sleep and cognitive impairment. It may be associated with Landau-Kleffner syndrome and loss of language skills. Characteristics of ESES include the following: Continuous spiking during slow-wave sleep, stage N3 with spike-wave complexes at 2-2.5 Hz Reduction in pattern during stage R sleep and wake state
Landau-Kleffner Syndrome	This disorder, also known as infantile acquired aphasia, involves sudden or gradual onset of loss of language skills and is characterized by nocturnal multifocal spikes and spike-wave discharges although seizures are rare IEA in 85% or more of slow-wave sleep

Describe sleepwalking disorder, including its symptoms and testing results

Sleepwalking disorder (somnambulism) is characterized by motor activity during sleep. During the episode, the patient may respond verbally to others but speech may not be clear because of reduced alertness. The patient’s eyes are usually open. Patients may also urinate in inappropriate places. Typically, the patient does not awaken easily and is confused if awakened and has little or no memory of the episode. Nocturnal PSG and audiovisual monitoring shows motor activity. Onset is usually during stage N3 sleep for children, although adults may have onset during stage N2 sleep, within the first few hours of sleep. The EEG shows high-voltage delta waves before and during the episode and sometimes alpha waves at onset, but artifacts caused by motor activity may obscure EEG activity. The ECG shows increased heart rate, and respiratory sensors show increased respirations. Patients may have increased transitions from stage N3 sleep and increased episodes of awakening during non-REM sleep

Discuss the impact of sleep deprivation on thermoregulation

Thermoregulation involves systems that are controlled automatically with the exception of engaging in physical activity and sleeping. The normal body temperature is about 37 degrees C, but this varies about 1 degree C, according to the circadian cycle and activities, with low points at about 3 am and high points at 6 am. People who suffer sleep deprivation tend to maintain a higher temperature in the morning with less overall variation. Body heat dissipates through conduction, convection, radiation, and evaporation. The body retains or increases heat through shivering, muscle activity, changes in hormones, changes in posture, vasoconstriction, and environmental changes (increased temperature, clothing). Thermoregulation is less stable in older adults. Production of heat decreases and heat loss increases. The temperature-regulating mechanism of the hypothalamus may reset internal temperature control at a lower level. Infants and children have larger body surface-to-weight ratios than adults, thinner skin, and a lower fat content. Infants can only produce heart by activity, shivering (> 3 months age), and nonshivering thermogenesis.

Discuss central sleep apnea and central alveolar hypoventilation syndrome, including symptoms and testing for these sleep disorders

Central sleep apnea involves apneic and hypopneic episodes without obstruction and usually results from cardiac or neurological disorders that cause impairment of ventilation. Snoring is usually mid, and individuals may complain of insomnia because they awaken frequently. Chest wall and abdominal movements do not occur during apneic periods with this breathing-related sleep disorder. Cheyne-Stokes respirations must be present (apnea, 10-60 seconds of hyperventilation, followed by another period of apnea). Nocturnal PSG shows decreased respiratory effort associated with decreased oxygen saturation.

Central alveolar hypoventilation syndrome results from impaired ventilatory control, characterized by low arterial oxygen levels and hypoventilation without apnea or hypopnea. Hypoventilation periods may persist for several minutes with sustained arterial oxygen desaturation and increased levels of carbon dioxide. This condition is often associated with obesity. Individuals may complain of feeling excessively sleepy or having insomnia. If this condition is severe, hypoxemia or hypercarbia may persist during waking hours

Discuss the impact of polycystic ovarian syndrome on sleep

Polycystic ovarian syndrome (PCOS) is an endocrine abnormality resulting in irregular menstrual cycles with rare or no ovulation and oligomenorrhea or amenorrhea, evidence of hyperandrogenism (virilization), and polycystic ovaries (found on ultrasound). Obesity is a common finding in PCOS as well as are acne, male pattern baldness, and hirsutism, resulting from increased testosterone production. The obesity combined with insulin resistance results in central obesity with enlargement of the abdomen and hyperinsulinism, which causes further increase in the production of male hormones (androgens). The obesity associated PCOS markedly increases the risk for OSAS by 30-40 times over those at the same weight but without PCOS. Additionally, stress associated with changes in the body, such as alopecia and increased facial hair, may impair sleeping.

Discuss the impact of chronic obstructive pulmonary disease on sleep

Chronic obstructive pulmonary disease (COPD) causes limitations in airflow and may include both emphysema and chronic bronchitis, or more often a combination. The primary components of COPD include the following:

• Progressive airflow limitation

• Inflammatory response that causes a narrowing of the peripheral airways and thickening of the vessel walls of the pulmonary vasculature

• Exertional dyspnea and chronic cough

Acute exacerbation can result in decompensation with increased hypoxemia with oxygen saturation less than 90% with tachycardia, tachypnea, cyanosis, change in mental status, and hypercapnia. Dyspnea and orthopnea are common symptoms so patients undergoing PSG may not be able to recline fully during testing. If COPD is severe, patients may sleep sitting upright in a chair. COPD when combined with sleep apnea-hypopnea can result in increased total sleep time, decreasing sleep efficiency, and a slight decrease in stage N1 sleep

Discuss the impact of Parkinson disease on sleep

Parkinson disease is an extrapyramidal movement motor system disorder caused by loss of brain cells that produce dopamine. Typical symptoms include tremor of face and extremities, rigidity, bradykinesia, akinesia, poor posture, and lack of balance and coordination, causing increasing problems with mobility, talking, and swallowing. Some patients may suffer depression, mood changes, and dementia (about 30%). Tremors usually present unilaterally in an upper extremity. Disorders in sleep, including RBD, may be an early symptom. Levodopa and Sinemet, commonly used to treat Parkinson disease, may cause increased anxiety, insomnia, and nightmares. Monoamine oxidase inhibitors, such as selegiline, are stimulants and may cause insomnia. Dopamine agonists, such as ropinirole, may cause increased drowsiness and sleep attacks. Sleep disorders associated with Parkinson disease include OSA, CSA, periodic breathing, and Cheyne-Stokes breathing. Restless leg syndrome is also common. During PSG, the patient may exhibit REM behavior disorder, frequently dislodging electrodes and other equipment, sucks as masks. Precautions to prevent falls should be observed

Discuss the sleep requirements for infants

0-1 months	The newborn sleeps about 16.5 hr/d, evenly spaced through both day and night
2-4 months	The infant continues to sleep a lot, about 15 hr/d but is often awake for periods in the morning, afternoon, and evening, so sleeping time during the night exceeds the sleep time during the day by about an hour
4-6 months	The child sleeps about 10-11 hours at night with two to three daytime naps that total 3-4 hours with total sleep time of 14.25 hours
6-8 months	The child begins to have more waking hours, sleeping 10-11 hours with two aps and total sleep time of about 14-14.25
8-10 months	The child continues to sleep about 10-11 hours at night and usually seeps through the night, with two naps in the daytime and total sleep time of about 14 hours
10-12 months	The child continues to sleep 10-11 hours at night with two naps in the daytime with total sleep time about 13.75 hours

Discuss the impact of menopause on sleep

Menopause occurs when amenorrhea persists for 12 months after the last menstruation. Hormonal changes can cause hot flashes, which are more common in the evening and at night, interrupting sleep and resulting in complaints of insomnia. Rates of OSA increase markedly after menopause as fat distribution changes with increased fat around the waist and abdomen, and weight tends to increase. Nocturia and urinary urgency become more common and increasingly interrupt sleep. Some women report symptoms of depression, which can also impair sleep. Depression may result directly from hormonal changes or from anxiety about aging and bodily changes. While hormone replacement therapy (HRT) can relieve some of the symptoms that interfere with sleep, concerns about damage to the cardiovascular system have sharply curtailed prescriptions for HRT. “Male menopause” is an age-related reduction in testosterone and tends to be less abrupt because hormone levels decrease more slowly; however, low testosterone levels can result in insomnia or other disturbances of sleep

Discuss the impact of coronary artery disease/angina pectoris on sleep

Coronary artery disease results in narrowing of the lumen of the coronary arteries, leading to ischemia of the cardiac muscle and angina pectoris, pain that may occur in the sternum, chest, neck, arms (especially the left), or back. The pain frequently occurs with crushing pain substernally, radiating down the left arm or both arms, although this type of pain is more common in men than women, whose symptoms may appear less acute and include nausea, shortness of breath, and fatigue. Elderly or diabetic patients may also have pain in the arms, no pain at all (silent ischemia), or weakness and numbness in the arms. Stable angina episodes usually last for less than 5 minutes and are fairly predictable exercise-induced episodes caused by atherosclerotic lesions blocking 75% or more of the lumen of the effected coronary artery. Precipitating events include exercise, decrease in environmental temperature, heavy eating, strong emotions, or exertion, including coitus. Stable angina episodes usually resolve in less than 5 minutes by decreasing activity levels and administering sublingual nitroglycerin

Discuss the impact of generalized epilepsy, such as Lennox-Gastaut and West syndromes, on sleep

Lennox-Gastaut syndrome is a severe, intractable seizure disorder with multiple types of seizures, occurring throughout waking and sleeping, and intellectual disability. Tonic-clonic seizures are common on awakening and may occur during sleep. Tonic seizures are most common during sleep: Generalized, slow, spike-wave complexes of 2.5 Hz or more; increase in activity during non-REM sleep with polyspikes and bursts of rapid activity at 10-20 Hz; Prolonged or continuous spike-wave discharges (usually inversely correlated to the degree of intellectual disability)

West syndrome is characterized by brain damage, resulting in infantile spasms, intellectual disability, and interictal EEG hypsarrhythmia (multi-focal and generalized high-voltage spikes with disorganized background tracing). Seizures usually occur while awake, although EEG abnormalities are evident during sleep: Increases in interictal epileptiform activity with spikes and slow wave discharges, occurring periodically during non-REM sleep; Decrease in hypersar-rhythmia (irregular spikes), occurring during stage R sleep

Discuss the sleep requirements and issues for older adults

Older adults take longer to fall asleep, awaken more frequently, and sleep less at night and more in the daytime than younger adults. About half of older adults have insomnia and about 65-70% have combined sleeping disorders. External factors, such as health changes, social changes, and medications, can affect sleeping. Typically, slow-wave sleep begins to decrease in adolescence, and continues throughout life. By middle age, many people complain they sleep less deeply and arouse more easily, especially in the 2nd half of the night. Sleep may become fragmented with numerous transient arousal periods. By very old age, some people no longer experience stage N3 sleep although stage R sleep remains at 20-25%; however, people with Alzheimer disease show decreased stage R sleep. Some older adults experience phase advance and an increased need for sleeping time and napping, possibly because sleep is less efficient with frequent arousals.

Discuss the pathophysiology of sleep: The diencephalon

The diencephalon is located above the brainstem and between the cerebral hemispheres. It comprises primarily gray matter and surrounds the third ventricle. The diencephalon contains a number of structures important to sleep and arousal.

• Thalamus: This gland receives sensory input from other parts of the central nervous system and carries them to appropriate areas of the cerebral cortex. The thalamus serves as a gateway and also an editor for sensory input (except for smell).

• Hypothalamus: This gland regulates heart rate, blood pressure, temperature, fluid and electrolyte balance, hunger, weight, stomach, intestines, and sleep; and produces substances that stimulate the pituitary gland to release hormones

• Optic chiasm: The optic nerves cross in this area anterior to the pituitary gland

• Posterior pituitary gland: This gland stores and secretes oxytocin and antidiuretic hormone, which are produced by the hypothalamus

• Mamillary bodies: These are active in the memory of smells

• Pineal gland: This gland is attached to third ventricle; it produces melatonin and mediates sleep

The oxyhemoglobin dissociation curve

The oxyhemoglobin dissociation curve is a graph that plots the percentage of hemoglobin saturated with oxygen (y axis) and different partial pressure of oxygen (PaO2 levels, x axis). A curve shift to the right represents conditions where hemoglobin has less affinity for oxygen (greater amounts of oxygen are released). A shift to the left has the opposite implications.

Low pH shifts the curve to the right, enabling increased unloading of hemoglobin to tissues. Elevated oxygen shifts to the left, causing increased affinity of hemoglobin for oxygen in the lungs. Small changes in fetal PO₂ result in greater loading or unloading of oxygen compared to adult hemoglobin. Because of the increased affinity for oxygen, lower tissue oxygen levels are needed to trigger the unload of oxygen. Thus, the infant will have a lower PaO2 and oxygen saturation before cyanosis is evident. Normal PaO2 is 80-100 mmHg, equal to 95-98% oxygen saturation. Levels less than 40 mmHg are dangerous.

Discuss the reticular formation

The reticular formation, located in the brainstem, receives neural impulses from everywhere in the body and is connected to both the cerebellum, which controls movement, balance, and coordination, and the limbic system (deep brain structures).

• The ascending pathways (dorsal and ventral), referred to as the reticular activating system (RAS), carry sensory information to the forebrain and cerebral cortex, and use a feedback method to control sleep and awake states. Sensory input and activity in the RAS bring about arousal and maintain the awake state. The RAS is linked to the motor system and controls movement during the awake state and atonia during the stage R sleep

• The descending reticular formation receives input from the hypothalamus and is involved in activation of the autonomic nervous system

Arterial oxygen

Arterial oxygen is carried in the red blood cells by hemoglobin. Each hemoglobin molecule can carry four molecules of oxygen, with 1 g of hemoglobin equal to 1.39 mL of oxygen (100 mL arterial blood carries 0.3 mL oxygen). When the hemoglobin is fully saturated (four oxygen molecules per molecule of hemoglobin), then arterial oxygen saturation is 100%. A small amount of oxygen remains dissolved in blood (PaO2 × 0.0031), but this has little effect on arterial oxygen content. The formula to determine arterial oxygen content (CaO2) is below:

CaO2 = [hemoglobin * arterial oxygen saturation (SaO2) * 1.39] + arterial partial pressure of oxygen (PaO2 × 0.003)

Within the sleep lab, a simplified formula is used to evaluate oxygen delivery (O2D):

O2D = [stroke volume * heart rate] * SpO2

Perfusion pressure is estimated by the systolic blood pressure. Systolic blood pressure = cardiac output * systemic vascular resistance

Substance-induced sleep disorders associated with alcohol use and withdrawal

Drug	Disorder	Characteristics
Alcohol intoxication	Insomnia	Sedation occurs during acute intoxications with increased sleeping and decreased wakefulness for 3-4 hours with increased stage N3 sleep and reduced stage R sleep. After this period, the patient experiences decreased stage N3 sleep, increased wakefulness, and increased stage R sleep with restlessness and sometimes vivid dreams.
Alcohol withdrawal	Insomnia	Gross disturbances of sleep with an increase in the amount of stage R sleep, often with vivid dreams. After withdrawal, insomnia with a light restless sleep may persist for weeks to years with a deficit in slow-wave sleep

The respiratory system during stage R sleep

The respiratory system during stage R sleep (REM sleep) changes as respirations become much more irregular in rate, amplitude, and tidal volume. Periodic breathing or central apneas (10-30 seconds) may occur during phasic REM sleep. Muscle hypotonia/atonia may affect the muscles of respiration, including the intercostals, and this can increase hypoventilation in patients with pulmonary disorders. This diaphragm muscle remains innervated by phrenic motor neurons, so it can compensate for the loss of muscle function; however, if the diaphragm is impaired, such as with neuromuscular disease, then hypoventilation occurs. The PaCO2 increases by 2-5 mmHg while the PaO2 and functional residual capacity decrease, increasing hypoxemia in patients with sleep disordered breathing because the compensatory ventilatory response is depressed. Upper airway resistance increases during stage R sleep and can lead to collapse of the airway and OSA.

How spinal muscular atrophy can impact sleep

Spinal muscular atrophy (SMA) comprises a number of different neuromuscular diseases with type I (Werdnig-Hoffman disease or “floppy infant syndrome”) the most severe with progressive weakness and wasting skeletal muscles caused by degeneration of anterior horn cells of the spinal cord and the motor nuclei of the brainstem. Children with type I are typically hypotonic at birth and are prone to aspiration because of weakness of the intercostal muscles, although the diaphragm is usually unaffected. These children may have frequent aspirations and pneumonia. PSG may show hypoventilation, sleep apnea, and hypoxemia. PSG may show hypoventilation, sleep apnea, and hypoxemia. Types II and III are characterized by weakness of peripheral muscles and scoliosis. Respiratory muscles may also have some degree of weakness, leading to respiratory failure. With SMA, PSG may indicate hypoventilation and hypoxemia, suggesting the need for noninvasive ventilation to prevent or delay progression of respiratory failure.

Forms of chronic insomnia

Psychophysiological	A self-perpetuating form in which anxiety about the inability to sleep interferes with sleeping. PSG shows increased wakefulness, increased sleep latency, and decreased sleep efficiency.
Idiopathic	Sleep disturbances that arose in infancy or childhood and have sustained without adequate explanation or remission
Paradoxical	PSG shows normal sleep, but the patient reports reduced or no sleep and often does not believe contrary lab results
Inadequate sleep hygiene	The patient suffers from sleep disturbances secondary to lifestyle choices and practices that may include daytime sleeping, substance abuse, arousing activities near bedtime, and environments that are not conductive to sleep
Behavioral insomnia of childhood	Poor sleep behavior secondary to parental/caregiver training that may include dependency on objects or routines, or a lack of limit-setting that addresses bedtime avoidance

Snoring

Snoring results from vibration within the respiratory system, often within the throat and nasal passages. The sound arises from the tissues vibrating against each other. Causes can include the following:

• Throat muscle weakness

• Obesity

• Nasal obstruction

• Tissues touching

• Drug use (alcohol or other muscle relaxant drugs)

• Supine position (the tongue may obstruct the airway)

Snoring increases during sleep because the muscles relax, causing partial closure of the airway. Usually, the more the restriction in airflow, the louder the snoring. If related to nasal obstruction only (primary), snoring is usually regular and periodic and may be soft to loud. While annoying, this type of snoring is not a threat to health. Snoring related to OSA is more irregular in rhythm and interrupted by periods of apnea-hypopnea and brief arousals. Patients may complain of headache on arising and chronic drowsiness.

Impact of amyotrophic lateral sclerosis (ALS) on sleep

Amyotrophic lateral sclerosis (ALS) is degenerative disease of the motor neurons from the anterior horns of the spinal cord and the motor nuclei in the lower brainstem. The neurons begin to die, and the muscles to which they are attached atrophy and weaken. Symptoms include increasing muscle weakness, twitching, spasticity, fatigue, and lack of coordination. Weakness of facial and pharyngeal muscles impairs the ability to swallow and cough, increasing the risk of aspiration and OSA. As respiratory muscles weaken, patients often develop central alveolar hypoventilation, requiring mechanical ventilation. Because of generalized weakness, patients may have difficulty following instructions required for physiological calibrations. Additionally, patients may need assistance to move or turn during the night and may need the head of the bed elevated. If patients have difficulty exhaling, then bi-level positive airway pressure is usually preferred over continuous positive airway pressure.

Impact of panic disorder on sleep

Panic disorder is characterized by chronic, repeated, and unexpected panic attacks, which present as overwhelming fear, apprehension, and terror when there is no specific cause. Panic attacks may last from minutes to several hours. Initial attacks usually occur in an anxiety-provoking situation, while successive attacks are spontaneous. Patients often report to an emergency department with shortness of breath and chest pain, believing they are having a heart attack or severe respiratory problems. Patients typically complain of multiple sleep problems, including difficulty falling and staying asleep and decreased total sleep time (TST) as panic attacks can occur during sleep, especially when associated with sleep deprivation. The panic attacks are not related to nightmares or night terrors, and patients do not show confusion or amnesia after awakening. PSG during panic attacks show they develop during late stage N2 sleep or early stage N3 sleep. While slow-wave sleep is normal in patients with panic disorder, muscle activity increases. REM latency remains normal or increased with normal density. Sleep onset is delayed; TST is decreased; and sleep is less efficient.

Sleep terror disorder

Sleep terror disorder (night terrors), an NREM-related parasomnia, is awakening abruptly, primarily during the first third of the night, during partial arousal from stage N3 (slow wave) sleep or, less commonly during stage N2 sleep. It most often occurs in children between the ages of 4 and 12 and usually resolves by adolescence. In adults, onset it usually between the ages of 20 and 30. Typically, the person sits up in bed and screams or cries and may flail about or fight against being touched but cannot be easily awakened. The episodes, lasting 1-10 minutes, include an autonomic response with increased heart rate, tachypnea, flushing, sweating, increased muscle tone, and pupil dilation. Once awakened, the person usually does not recall the dream but feels frightened. The person falls quickly back to sleep and has no memory of the episode on awakening in the morning. Sleep terror disorder may be associated with sleep walking. PSG shows onset during non-REM sleep with delta waves on the EEG, although theta or alpha activity may be evident during the episode, suggesting partial arousal. The ECG shows a heart rate up to 120 beats/minute. The EMG shows increased activity.

The risk for metabolic syndrome as a result of sleep deprivation

Metabolic syndrome is a group of abnormalities, including the following:

• Abdominal obesity: Males, waist over 40 inches; females, waist over 35 inches

• Hypertension: 130/85 mmHg or more

• High cholesterol levels (increased triglycerides and LDL and reduced HDL) and atherosclerosis

• Insulin resistance

• Fasting blood glucose 100 mg/dL or more

• Increased risk of blood clots and vascular inflammation

In general, people who sleep less than 6 hours a night ad more than 9-10 hours per night are at risk of weight gain and increased risk of metabolic syndrome. Patients often present with disrupted sleep patterns that coincide with increased weight and evidence of metabolic syndrome. Metabolic syndrome is associated with OSA because of the impact obesity has on respiration.

Restless leg syndrome and periodic leg movements of sleep

RLS is characterized by pain and paresthesia in the legs at rest, especially in the evening and at night when trying to sleep. Some people also have periodic jerking of limbs. Moving the legs relieves discomfort, but this often results in difficulty sleeping and resultant exhaustion during the daytime, so patients may complain of insomnia. Neurological examination is typically normal, but a family history of RLS is common. Some people have relief of symptoms if they reduce caffeine, alcohol, and tobacco use. RLS does not require PSG because it is an awake disorder that interferes with sleep rather than a direct sleep disorder. RLS can be evaluated with suggested with immobilization test to diagnose periodic limb movement of wakefulness (PLMW). RLS is diagnosed with more than 40 PLMW an hour

PLMS are similar but occur during sleep and are often associated with RLS (occurring in about 80% of patients with RLS) with 5 or more PLMS usually within the first half of the night. PLMS is common in other patients and may be noted on anterior tibialis electromyogram but these movements may not be clinically relevant.

Various medications that may interfere with sleep studies

• Anti-anxiety medications: Benzodiazepines (Ativan, Valium, Xanax) in particular can cause a reduced time of sleep onset and increased total sleep time

• Antidepressants: Tricyclic antidepressants (amitriptyline, nortriptyline) can cause decreased sleep latency and wakefulness. They may also increase limb movements during sleep. Selective serotonin reuptake inhibitors (Prozac, Zoloft) can cause increased limb movements during sleep also, as well as rolling eye movements

• Antihypertensives: The beta-blocker class of medications (atenolol, metoprolol) can alter sleep-waking function. This includes fatigue, insomnia, nightmares, and vivid dreams.

• Antiseizure medications: Patients taking these medications (phenobarbital, Dilantin) have increased sleepiness prolonged sleeping times

• Opioids: These medications can cause respiratory depression, which is accentuated in patients with chronic respiratory diseases, and may cause slower ventilations during a sleep study. The symptoms of respiratory depression with these medications may be exaggerated during sleep

Respiratory system during stages N1, N2, N3

The respiratory system during stages N1, N2, N3 is completely under the control of the autonomic nervous system and is not impacted by activities of the awake state; thus, respirations should become very regular in both the respiratory rate and the amplitude:

• Stages N1 and N2: Some periodic breathing (irregular respirations with brief periods of apnea-hypopnea) may occur at sleep onset and throughout stage N1 but should disappear by stage N2. Periodic breathing is more common with congestive heart failure.

• Stage N3: Respirations should remain regular with some decreased noted in tidal volume and functional residual capacity as well as a decrease in minute ventilation. PaCO2 increases, and PaO2 decreases. Inspiratory airflow decreases, and upper airway resistance increases. Muscle activity (muscles of respiration) decreases.

General purpose and elements of CPAP

Continuous positive airway pressure (CPAP) can be delivered by a wide range of equipment, starting with the most basic, relatively inexpensive machines to expensive computerized equipment. All positive airway pressure devices have an air blower that delivers pressurized room air to an interface or mask. Pressure can be increased or decreased by adjusting the speed or the amount of airflow, with most machines generating pressure ranging from 2-20 cm H2O. Carbon dioxide is expelled through a vent or nonrebreather. These may be large or small, but all have filters in the back and can be used with a variety of masks (e.g., nasal, orofacial (full face), nasal pillow). Some have built-in heated humidifiers, and all can be used with cool passover or heated humidifiers. Many basic machines do not adjust for environmental factors, such as altitude, and many do not have an internal memory to generate sleep reports. Some may switch between 110 and 220 volts. Even basic machines allow for a gradual rise to selected pressure. More sophisticated CPAP machines usually have software and downloadable memories that can provide reports regarding respiratory events. Altitude compensation is usually automatic.

Nonrespiratory conditions that impact sleep in infants and small children

Neonates and infants	Colic is a circadian disorder in which the child develops abdominal cramping and pain during the evening and night Gastric reflux or milk intolerance also can result in crying and discomfort but usually is evident during the daytime CSA and OSA may result in crying at night
Ages 1-5	Non-REM parasomnias may occur The child may have reduced sleeping needs for both nighttime sleeping and napping, and this can lead to frustration and resistance to sleeping that results in sleeping disorders, such as conditioned insomnia The child may experience sleep terrors, nightmares, or nocturnal seizures that interfere with sleep
Ages 5-11	Non-REM parasomnias may occur The child may be sensitive to noise and arouse easily Sleep hygiene may be inadequate The child may experience exaggerated fears (e.g., loss of parent, injury) that interfere with sleep
Adolescents	Medications used to treat behavioral/psychiatric disorders may interfere with sleep Busy schedules often preclude adequate sleep Delayed sleep phase is common, so the adolescent goes to sleep later and has difficulty awakening because of inadequate sleep time Onset of narcolepsy may occur during adolescence

The limbic system and sleep

The limbic system, in the region of the diencephalon, is essential to regulation of emotion, hormones, mood, and pain or pleasure sensations. The limbic system is comprised of several structures, including:

• Amygdala: This is an almond-shaped grouping nuclei that are responsible for mediating arousal, emotion, and fear responses, as well as hormones

• Cingulate gyrus: This structure is responsible for matching sensory input with emotional response

• Hippocampus: This is a group of neurons responsible for organizing and processing memories, spatial relationships, and emotional regulation

• Hypothalamus: This is a structure that is involved in almost all body processes, to include autonomic functions, emotions, homeostasis, endocrine processes, and sleep regulations

• Thalamus: This is a group of cells that mediates motor function, and receives, processes, and relays sensory signals to and from the cortex, playing an important role in sleep. Fibers release neurotransmitters that help to control arousal

Hemoglobin and hematocrit

Hemoglobin and hematocrit are particularly important in evaluating the amount of oxygen in blood. Red blood cells (RBCs or erythrocytes) contain hemoglobin (95% of mass), which carries oxygen throughout the body. The heme portion of the cell contains iron, which binds to the oxygen.

• Hemoglobin, a protein found in erythrocytes, uses iron to bind and transport oxygen. Deficiencies of amino acids, vitamins, or minerals can cause a decrease, impacting healing and reducing oxygen to tissue. Dehydration and severe burns can cause an increase. Normal values for men are 13-18 g/dL, and for women, 12-16 g/dL

• Hematocrit measures the percentage of packed blood cells in 100 mL of blood. A decrease can indicate blood loss and anemia. An increase may indicate dehydration, and measurements may monitor the effects rehydration. Normal values for men are 42-52%, and for women 37-48%

Sleep compliance

Ventilation carries air with oxygen into the lungs and waste products, including carbon dioxide, out of the lungs. An important factor is compliance. The elasticity and expandability of the lungs and thoracic cavity determine the volume/pressure relationship

• Compliance decreases when lung expansion is limited or “tight” (pneumothorax, pulmonary edema, atelectasis), requiring increased effort of breathing

• Compliance increases with overdistention of the thorax or loss of elasticity as in COPD

Impact of spina bifida/myelomeningocele on sleep

Spina bifida is a neural tube defect with an incomplete spinal cord and often missing vertebrae that allow the meninges and spinal cord to protrude through the opening.

Myelomeningocele is a spina bifida cystica with the meningeal sac containing spinal fluid and part of the spinal cord and nerves, resulting in varying degrees of muscle paralysis and loss of sensation below the area of involvement as well as hydrocephalus. Children are at an increased risk for apnea (especially OSA and CSA), hypoventilation, and aspiration. The nocturnal PSG is important as patterns of hypoventilation and sleep-disordered breathing may not be obvious during waking hours. Infants with myelomeningocele are less likely to arouse in response to hypercapnia than other infants

Impact of congenital myotonic dystrophy on sleep

Congenital myotonic dystrophy causes damage during the fetal period that results in hypoplasia of the lungs and diaphragm; thus, the infant requires ventilatory support at birth. Both apnea and sleep-disordered breathing may occur in the neonatal period, and nocturnal hypoventilation may persist. Symptoms vary, depending on the severity of the disease, with some children exhibiting only slight hypotonia and impaired sucking and swallowing reflexes (increasing the risk of aspiration), while others present with severe respiratory failure. Older children and adolescents may have hypersomnolence, OSA, and disruption of sleep as well of gastroesophageal reflux, so a PSG may require a pH sensor. Cardiac arrhythmias are common and may be associated with hypercapnia, hypoxemia, and hypoventilation (resulting in acidosis), so careful observation of the ECG tracings is critical

Narcolepsy

Narcolepsy is characterized by repeated periods of falling asleep during waking hours daily for at least 3 months. Onset is often during childhood or adolescence and is rare after 40 years of age. Onset is often preceded by an acute psychological stressor or disruption of the sleep-wake schedule. There are two identified types of narcolepsy:

• Type 1 requires the presence of cataplexy accompanied by one or both of the following:

  • Either a mean sleep latency (MSL) of ≤8 minutes and 2+ sleep-onset REM periods on the MSLT or a sleep onset REM within 15 minutes of sleep onset on nocturnal PSG

  • CSF hypocretin-1 is ≤110 pg/mL

• Type 2 is also known as narcolepsy without cataplexy and:

  • Either a mean sleep latency (MSL) of ≤8 minutes and 2+ sleep-onset REM periods on the MSLT or a sleep onset REM within 15 minutes of sleep onset on nocturnal PSG

  • CSF hypocrentin-1 > 110 pg/mL

Episodes of sleep apnea and periodic limb movement may be evident

The cardiovascular system during sleep

The cardiovascular system during sleep responds to the control of both the sympathetic and parasympathetic nervous systems, causing changes in heart rate and blood pressure, although stroke volume usually remains constant with the lowest cardiac output during the final stage R sleep cycle. The changes can cause cardiovascular ischemia in some individuals:

• Stages N1, N2, and N3 sleep: For most patients, the parasympathetic nervous system is primary, causing a decrease in both the heart rate and blood pressure (decreased peripheral vascular resistance) by 5-15%

• Stage R sleep: During the phasic stage of REM sleep, the sympathetic nervous system affects the cardiovascular system by increasing both the heart rate and blood pressure (increased peripheral vascular resistance). However, during tonic REM sleep, the parasympathetic nervous system again lowers the heart rate, sometimes to bradycardic levels, and blood pressure

• Arousal response: The sympathetic nervous system is involved in arousals, increasing heart rate and blood pressure

Pulmonary changes associated with aging and how sleep is affected by these changes

Pulmonary changes associated with aging typically include decreased pulmonary elasticity, decreases in alveolar surface area and size of airways, weakening of muscles respiration (diaphragm and intercostals), and chest wall rigidity, so exchange of oxygen is impaired. Forced expiratory volume and forced vital capacity are also reduced. Overall strength is often decreased, so there is less ability to breathe deeply, and cough reflex and ciliary action are also decreased. Older adults may have less sensitivity to changes in oxygen and carbon dioxide levels (hypoxia, hypercapnia), so the increase in respiratory rate to compensate may be impaired and less noticeable. These changes may affect sleep in the older adult and may cause further decreases in oxygen saturation during episodes of sleep apnea. Episodes of hypoxia may be prolonged because of increased airway resistance

Impact of obsessive-compulsive disorder on sleep

OCD is a disorder in which patients are plagued by obsessions or compulsions that interfere with employment and social, interpersonal, and other daily activities and last more than 1 hour daily

• Obsessions are unwanted, repeated, and uncontrollable ideas, images, or urges that come to mind involuntarily despite attempts to ignore or suppress them

• Compulsions are repeated, unwanted patterns of behavior (impulses) to perform apparently irrational or useless acts (e.g., washing hands, arranging and rearranging items) that are often responses to obsessions and done to reduce stress

A sense of dread may develop if the compulsion is resisted, and some try to ignore and suppress thoughts or behaviors. Patients often have pronounced sleep disturbances because of their obsessions and compulsions, and their need to carry out repetitive behavior may make sleep studies difficult. They may resist any reusable equipment (e.g., masks) because of fear of germs. PSG may show decreases in total sleep time, increased awakening, and decreased stage N3 sleep.

REM-related sleep disorders of REM sleep behavior disorder and recurrent isolated sleep paralysis

REM-related parasomnias occur during stage R sleep and include REM sleep behavior disorder, recurrent isolated sleep paralysis, and nightmare disorder.

REM sleep behavior disorder	During stage R sleep, periods of muscle activity in which the patient may act out motor activities of the dream, such as flailing arms, kicking, hitting, running, and jumping out of the bed. Typically, the patient’s eyes are closed during episode, which is most common in men 60-70 years of age
Recurrent Isolated Sleep Paralysis	Muscle atonia occurs during onset of sleep (hypnagogic) or on waking (hypnopompic), most often during adolescence. The patient can see and breathe but is not able to move for periods of seconds to minutes