crc 432 subacute care module iv polysomnography (psg) & sleep-disordered breathing (sdb)

CRC 432 Subacute CareModule IV

Polysomnography (PSG)

&

Sleep-Disordered Breathing (SDB)

Normal Stages of Sleep

Two Major States of Sleep:

• NREM

• REM

Cycle back & forth every 60 to 90 minutes (4 to 5 cycles) during normal 8-hour sleep.

NREM

• 1st stage of sleep

• Restorative state

• Three stages, each progressively deeper

• Stage 1:– Eye roll slowly– Low amplitude waves– 5% to 10% sleep in stage 1

NREM• 2 to 10 minutes progresses to stage 2

• Stage 2:– Sharp spike called “K-complexes” (sleep spindles)– 405 to 50% sleep in stage 2

• Stage 3:– Deepest stage of sleep– EEG demos “delta waves” (slow wave sleep)– Restorative sleep– Difficult to awaken person– Growth hormones released

NREM

• Body muscles exhibit tone

• Core temp drops

• Regulation of ventilation maintained

• RR slow

• VT decreases

• PaCO2 increases

• Occupies 75% of sleep (restorative sleep)

REM

• Brain active; dreaming

• 25% of total sleep period

• Decreased skeletal muscle tone

• Paralyzing effect

• Paralysis causes episodes of hypoxemia & hypercapnia

• Loss of sketal muscle tone affect pharyngeal muscles

REM

• Increased upper airway resistance (pharyngeal muscles relax)

• Upper airway lumen decreased

• Tongue & soft tissues relax, causing upper airway obstruction

• Cardiac dysrhythmias common

• Active brain activity, dreaming, & paralysis

Sleep Architecture

• Pattern of various sleep stages a person enters throughout the night.

• Each person has a distinct sleep architecture

Sleep Apnea

• Apnea - cessation of airflow from the mouth and nose for at least 10 seconds during sleep.

• Dyssomnia - a group of disorders characterized by difficulty in going to sleep, or staying asleep or excessive daytime sleepiness.

Sleep Apnea

• Parasomnia - any of several disorders that frequently interfere with sleep, occurring especially among children, and including sleepwalking, night terrors, and bed-wetting (nocturnal enuresis).

Sleep Apnea

• Types of sleep apnea– Obstructive (OSA)– Central (CSA)– Mixed (OSA & CSA)

• Obstructive sleep apnea– Most common form of sleep apnea– Drive to breathe is intact– Upper airway intermittently becomes obstructed during

sleep– Respiratory muscles work harder & harder to move air– Patient partially awakens– Airways clears, & ventilation resumes– Depending on severity, cycle may occur hundreds of

times/night

Sleep Apnea

Sleep Apnea

• Central Sleep Apnea– Central drive to breathe is intermittently absent

during sleep– When efforts to breathe stop, respiratory muscles

fail to contract– Airflow through the mouth and nose ceases

• Mixed Sleep Apnea– Patient has both OSA & CSA

Sleep Apnea

• OSA Pathophysiology– The muscles of the soft palate around the base of the

tongue and the uvula relax, obstructing the airway.– Upper airway tissues relax to levels below waking state.

– Upper Raw increases as airway becomes occluded.

– Inspiratory muscles contract more forcefully.– Increased negative intrathoracic pressure to overcome

obstruction.

Sleep Apnea

• OSA Pathophysiology– Wet paper soda straw analogy

• Straw collapses as air is drawn through more forcefully

– Upper airway obstruction may cause • Apnea• Hypercarbia• Hypoxemia

Sleep Apnea

• OSA Pathophysiology– Patient enters a “lighter” stage of sleep– Muscle tone returns to upper airway– Hypoxemia & hypercapnia arouse patient– Breathing resumes – When patient returns to deeper stage sleep,

process repeats– Hundreds of cycles of deeper-lighter stages

throughout the night

Sleep Apnea

• OSA Clinical Features– Sleep-disordered breathing ranges from

• Benign snoring with no health consequences - to -

• OSA with severe clinical consequences

Sleep Apnea

• OSA Clinical Features– Snoring– Excessive daytime somnolence– Morning headaches– Sleep fragmentation– Memory loss– Confusional awakenings

Sleep Apnea

• OSA Clinical Features– Personality changes– Impotence– Night sweats– Cardiac dysrhythmias– Pulmonary/systemic hypertension– CHF– Nocturnal enuresis

Sleep Apnea

• OSA Clinical Features– Daytime hypersomnolence most common symptom– Results from sleep fragmentation– Daytime hypersomnolence leads to

• Impaired cognitive function• Impaired psychomotor function

Sleep Apnea• OSA Clinical Features

– General appearance of OSA patients• Obesity

• Short, thick neck

• Large tongue

• Daytime vital signs often normal at rest

• 50% are hypertensive while awake

• Breathing pattern/auscultation normal while awake

Sleep Apnea

• OSA Clinical Features– Almost all OSA patients snore– NOT all snorers have OSA– 25% men & 15% women snore– Patients NOT aware of problem– Spouse generally is first alerted to problem– Heart rate changes & dysrhythmias common

during OSA episodes

Sleep Apnea

• OSA Clinical Features– Bradycardia before apnea; tachycardia

immediately after– PVCs most common dysrhythmias– Asystole in 10% of patients; lasts few seconds

Sleep Apnea

• Long-Term Cardiopulmonary Changes Occurring with Untreated OSA– nocturnal dysrhythmias– diurinal hypertension– pulmonary hypertension– R or L ventricular failure– myocardial infarction (MI)– stroke

Sleep Apnea

• OSA in Children– Snoring is hallmark symptom– Can occur at any age or gender– May be overweight or have failure to thrive– Children may be sleepy or hyperactive– Developmental delay– Poor school performance– Aggressive behavior/ social withdrawal

Sleep Apnea

• CSA Pathophysiology– Cessation of airflow through nose & mouth 2nd

to lack of diaphragmatic & respiratory muscle movement

• CSA Clinical Features– Little daytime effect– Patient does not recognize problem– Insomnia most common complaint– Mild snoring

Sleep Apnea

• Upper Airway Resistance Syndrome (UARS)– Symptoms similar to those with snoring & OSA– Severe UARS causes frequent sleep interruptions– Do NOT desaturate (NO hypoxia)– Positive response to CPAP use– UARS believed to be under-recognized

Sleep Apnea

• Observation of hospitalized patients– Gross sleeping characteristics

• Snoring?

• Breathing pauses?

• Cyanosis?

• Note sleeping position

• Note breathing pattern

• oximetry

Sleep Apnea

• Observation of Hospitalized Patient– Oximetry

• Gradual decrease on O2 SAT may indicate nocturnal hypoventilation, NOT sleep apnea

• Pattern of sharp decline, followed by sharp increase to baseline may indicate sleep apnea

Sleep Apnea

• Polysomnographic Studies– Diagnostic Overnight PSG– Diagnostic Daytime Multiple Sleep Latency

Test (MSLT) – Two-Night PSG with CPAP Titration – Split-Night PSG with CPAP Titration

Sleep Apnea

• Diagnostic Overnight PSG - General monitoring and evaluation.

• Diagnostic Daytime Multiple Sleep Latency Test (MSLT) - Used to diagnose narcolepsy, and measure the degree of daytime sleepiness. To ensure accurate results, it is performed on the morning following a Diagnostic Overnight PSG

Sleep Apnea

• Two-Night PSG with CPAP Titration - general monitoring and diagnostic evaluation conducted first night. If sleep apnea is discovered, patient returns second night to determine the necessary CPAP pressure required to alleviate apnea.

• Split-Night PSG with CPAP Titration - conducted when moderate or severe sleep apnea has been discovered, or strongly suspected during the first part of the night’s study. The second half of the night is used for CPAP titration.

Sleep Apnea

• Apnea: cessation of inspiratory gas flow through both the nose and mouth for at least 10 seconds.

• Hypopnea: 30% or more decline in airflow with a SaO2 decrease by at least 4%.

Sleep Apnea

• Apnea-Hypopnea Index (AHI)

• Mild: AHI 5 to 14, oxygen saturation ≥ 86%, and minimal daytime disability.

• Moderate: AHI 15 to 30, oxygen saturation 80% to 85% ,and significant work or social dysfunction due to drowsiness and loss of concentration.

• Severe: > 30, oxygen saturation ≤ 79%, and incapacitation.

Sleep Apnea

• Respiratory Disturbance Index (RDI) - number of apneas plus hypopneas per hour of sleep, and quantifies SDB.

Sleep Apnea

• OSA Treatment– CPAP acts as pneumatic splint, & maintains

upper airway patency during inspiration

– CPAP added in increments of 2.5 cm H2O until apneas and snoring eliminated

– Uvulopalatopharyngoplasty (UPPP): eliminates snoring, but OSA persists in 50% of cases

Sleep Apnea

• Periodic limb movement disorder (PLMD) and restless legs syndrome (RLS) are distinct disorders, but often occur simultaneously.

• Both PLMD and RLS are also called (nocturnal) myoclonus, which describes frequent or involuntary muscle spasms.

Sleep ApneaPeriodic Limb Movement Disorder (PLMD)• affects people only during sleep.• characterized by behavior ranging from shallow,

continual movement of the ankle or toes, to wild and strenuous kicking and flailing of the legs and arms.

• abdominal, oral, and nasal movement sometimes• leg movement more typical than arm movement. • typically occur for 0.5 to 10 seconds, in intervals

separated by five to 90 seconds.

Sleep Apnea

• PLMD– repetitive, involuntary movement during the night– movements usually occur in deep stage two sleep– often causes arousal, poor sleep, which may lead to

sleep maintenance insomnia and/or excessive daytime sleepiness

– considered a sleep disorder, because the movements often disrupt sleep and lead to daytime sleepiness.

Sleep Apnea

• PLMD– The causes of PLMD are unknown– people with a variety of medical problems,

including Parkinson's disease and narcolepsy, may have frequent periodic limb movements in sleep

– PLMD may be induced by medications, e.g., antidepressants

Sleep Apnea

• PLMD (Treatment)– Parkinson's disease drugs, anticonvulsant

medications, benzodiazepines, and narcotics – anti-Parkinson's medications first line of defense – medical treatment of PLMD significantly reduces

or eliminates the symptoms – no cure for PLMD– medical treatment must be continued to provide

relief

Sleep Apnea

• PLMD (Treatment)– Usual treatment is a combination of levodopa

and carbidopa (Sinemet)

Sleep Apnea

• PLMD– incidence increases with age – occurs in 5% of people ages 30 to 50;

44% of people over age of 65– 12.2% of patients suffer from

insomnia; 3.5% patients exhibit excessive daytime sleepiness may experience PLMD.

Sleep Apnea

• RLS– described as early as the 16th century, but was

not studied until the 1940s– irresistible urge to move the legs while at rest– person experiences vague, uncomfortable

feeling while at rest – only relieved by moving the legs

Sleep Apnea• RLS

– symptoms may be present all day long, making it difficult for an individual to sit motionless

– may be present only in late evening. – late evening symptoms can lead to sleep onset

insomnia, which tends to compound the effects of RLS

– pregnancy, uremia, and post-surgery conditions have also been known to increase incidence of RLS.

Sleep Apnea• RLS

– strong urge to move legs – need to move often accompanied by uncomfortable

sensations : "creeping," "itching," "pulling," "creepy-crawly," "tugging," or "gnawing."

– symptoms start or become worse at rest– the longer at rest, the greater the chance symptoms

will occur – symptoms get better leg movement– relief complete or partial, but generally starts soon

after starting activity– relief persists as long as motor activity continues

Sleep Apnea

• RLS– symptoms are worse in evening, especially

when person lies down– activities bothersome at night are not

bothersome during the day

Sleep Apnea• RLS (Treatment)

– dopaminergic agents, used to treat Parkinson's disease, have been shown to reduce RLS symptoms and PLMD, and are considered initial treatment of choice

– benzodiazepines (clonazepam and diazepam) prescribed for patients who have mild or intermittent symptoms

– help patients obtain a more restful sleep– do not fully alleviate RLS symptoms and can cause

daytime sleepiness– because these depressants also may induce or

aggravate sleep apnea in some cases, they should not be used in people with this condition.

Sleep Apnea

• RLS (Treatment)– no particular drug is effective for everyone

with RLS– lifelong condition for which there is no cure– diagnosis of RLS does not indicate the onset

of another neurological disease

Sleep Apnea

• RLS– incidence increases with age. – Affects 5% of population– Approximately 80% of people with

RLS have PLMD, though most people with PLMD do not experience RLS

Sleep Apnea• Multiple Sleep Latency Testing (MSLT)

– Measures degree of sleep tendency or sleepiness– Conducted during day following PSG– 5 naps for < 30 min, start every 2 hours during day,

e.g., 8 AM, 10 AM, 12 PM, 2 PM ,4 PM– Averages number of minute to fall asleep (sleep onset

latency)– Determines if REM stage occurs during any naps– Same leads as PSG– Patient MUST remain awake between naps– Diagnoses narcolepsy

Sleep Apnea

• MSLT– Normal to fall asleep within 15 minutes during

daytime nap– Falling asleep within 8 minutes & entering REM

indicate narcolepsy

Sleep Apnea

• Narcolepsy– Permanent and overwhelming feeling of

sleepiness and fatigue (90%)– Frequently unrecognized for many years– Could be delay of 10 years between onset and

diagnosis

Sleep Apnea• Narcolepsy

– Symptoms• Dream-like hallucinations• Feeling weak or paralyzed for a few seconds• Sleep paralysis (25%)• Cataplexy (75%)• Hypnagogic hallucinations (30%)

Sleep Apnea• Sleep paralysis (25%)

– Abnormal episode of REM sleep atonia– Unable to move for few minutes– Often upon falling asleep or awakening

• Cataplexy (75%)– Sudden muscle weakness triggered by emotions– Knees buckle– Laughing, elation, surprise, or anger– Patient may fall and become completely

paralyzed a few minutes

Sleep Apnea

• Hypnagogic hallucinations (30%)– Dream-like auditory or visual hallucinations– Occur when dozing off, falling asleep, or awakening

Sleep Apnea

• Narcolepsy Treatment– 7 to 8 hours sleep– Regularly scheduled daytime naps– Avoid heavy meals and alcohol before sleeping– modafinil (Provigil), stimulant– methylphenidate (Ritalin) or other amphetamines– tricyclic antidepressants: protriptyline (Vivactil)

or imipramine (Tofranil)

Sleep Apnea

• Narcolepsy Treatment– Antidepressants suppress REM sleep and

eliminate symptoms of cataplexy, hypnagogic hallucinations, and sleep paralysis